-#LyX 1.1 created this file. For more info see http://www.lyx.org/
-\lyxformat 218
+#LyX 1.2 created this file. For more info see http://www.lyx.org/
+\lyxformat 220
\textclass article
+\begin_preamble
+\usepackage[colorlinks=true,linkcolor=blue]{hyperref}
+\end_preamble
\language english
\inputencoding default
\fontscheme pslatex
\paperpackage a4
\use_geometry 0
\use_amsmath 0
+\use_natbib 0
+\use_numerical_citations 0
\paperorientation portrait
\secnumdepth 3
\tocdepth 3
\papersides 1
\paperpagestyle fancy
+\layout Comment
+
+Please note: double dashed longoptions (e.g.
+ --version) need three dashes in this document to be visable in html and
+ pdf output.
\layout Title
SDCC Compiler User Guide
\layout Section
-
+\pagebreak_top
Introduction
\layout Subsection
\newline
The latest version can be downloaded from
-\begin_inset LatexCommand \htmlurl{http://sdcc.sourceforge.net/}
+\begin_inset LatexCommand \url{http://sdcc.sourceforge.net/}
\end_inset
\emph on
freeware
\emph default
-; source code for all the sub-packages (asxxxx assembler/linker, pre-processor)
- is distributed with the package.
+; source code for all the sub-packages (pre-processor, assemblers, linkers
+ etc) is distributed with the package.
This documentation is maintained using a freeware word processor (LyX).
-
-\layout Standard
-
+\newline
This program is free software; you can redistribute it and/or modify it
- under the terms of the GNU General Public License as published by the Free
- Software Foundation; either version 2, or (at your option) any later version.
+ under the terms of the GNU General Public License
+\begin_inset LatexCommand \index{GNU General Public License}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{GPL}
+
+\end_inset
+
+ as published by the Free Software Foundation; either version 2, or (at
+ your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE.
\family default
Interesting items and new terms are printed in
\emph on
-italicised type.
+italic.
\layout Subsection
Compatibility with previous versions
\layout Itemize
short is now equivalent to int (16 bits), it used to be equivalent to char
- (8 bits)
+ (8 bits) which is not ANSI compliant
\layout Itemize
-the default directory where include, library and documention files are stored
- is no in /usr/local/share
+the default directory for gcc-builds where include, library and documention
+ files are stored is now in /usr/local/share
\layout Itemize
char type parameters to vararg functions are casted to int unless explicitly
will push a as an int and as a char resp.
\layout Itemize
-option --regextend has been removed
+option ---regextend has been removed
+\layout Itemize
+
+option ---noregparms has been removed
\layout Itemize
-option --noreparms has been removed
+option ---stack-after-data has been removed
\layout Standard
\layout Standard
The SDCC home page at
-\begin_inset LatexCommand \htmlurl{http://sdcc.sourceforge.net/}
+\begin_inset LatexCommand \url{http://sdcc.sourceforge.net/}
\end_inset
\layout Standard
-\family sans
-\series bold
-sdcc -c --model-large -o large _atoi.c
-\family default
-\series default
- (where large could be a different basename or a directory)
-\newline
-
-\layout Standard
-
-
\family typewriter
char KernelFunction3(char p) at 0x340;
\newline
If you can think of some more, please send them to the list.
\newline
-\newline
+\layout Section
-\emph on
-<pending: And then of course a proper index-table
-\begin_inset LatexCommand \index{index}
+Installation
+\begin_inset LatexCommand \index{Installation}
\end_inset
->
-\layout Section
-Installation
\layout Subsection
-Linux/Unix Installation
-\layout Enumerate
-
+Configure Options
+\begin_inset LatexCommand \index{Configure Options}
-\series medium
-Download the source package, it will be named something like sdcc-2.x.x.tgz.
-\layout Enumerate
+\end_inset
-\series medium
-Bring up a command line terminal, such as xterm.
-\layout Enumerate
+\layout Standard
+The install paths, search paths and other options are defined when running
+ 'configure'.
+ The defaults can be overriden by:
+\layout List
+\labelwidthstring 00.00.0000
-\series medium
-Unpack the file using a command like:
-\family sans
-\series bold
-"tar -xzf sdcc-2.x.x.tgz
-\family default
-\series default
-"
-\series medium
-, this will create a sub-directory called sdcc with all of the sources.
-\layout Enumerate
+---prefix see tabel below
+\layout List
+\labelwidthstring 00.00.0000
-Change directory into the main SDCC directory, for example type:
-\family sans
-\series bold
-"cd sdcc
-\series default
-".
-\layout Enumerate
+---exec_prefix see tabel below
+\layout List
+\labelwidthstring 00.00.0000
+---bindir see tabel below
+\layout List
+\labelwidthstring 00.00.0000
-\series medium
-Type
-\family sans
-\series bold
-"./configure
-\family default
-\series default
-".
- This configures the package for compilation on your system.
-\layout Enumerate
+---datadir see tabel below
+\layout List
+\labelwidthstring 00.00.0000
+docdir environment variable, see tabel below
+\layout List
+\labelwidthstring 00.00.0000
-\series medium
-Type
-\family sans
-\series bold
-"make
-\family default
-\series default
-"
-\series medium
-.
+include_dir_suffix environment variable, see tabel below
+\layout List
+\labelwidthstring 00.00.0000
-\series default
- All of the source packages will compile, this can take a while.
-\layout Enumerate
+lib_dir_suffix environment variable, see tabel below
+\layout List
+\labelwidthstring 00.00.0000
+sdccconf_h_dir_separator environment variable, either / or
+\backslash
-\series medium
-Type
-\family sans
-\series bold
-"make install"
-\family default
-\series default
- as root
-\series medium
-.
+\backslash
+ makes sense here.
+ This character will only be used in sdccconf.h; don't forget it's a C-header,
+ therefore a double-backslash is needed there.
+\layout List
+\labelwidthstring 00.00.0000
-\series default
- This copies the binary executables, the include files, the libraries and
- the documentation to the install directories.
-\layout Subsection
+---disable-mcs51-port Excludes the Intel mcs51 port
+\layout List
+\labelwidthstring 00.00.0000
-Windows Installation
-\layout Standard
+---disable-gbz80-port Excludes the Gameboy gbz80 port
+\layout List
+\labelwidthstring 00.00.0000
+---disable-z80-port Excludes the z80 port
+\layout List
+\labelwidthstring 00.00.0000
-\emph on
-<pending: is this complete? where is borland, mingw>
-\newline
+---disable-avr-port Excludes the AVR port
+\layout List
+\labelwidthstring 00.00.0000
-\newline
+---disable-ds390-port Excludes the DS390 port
+\layout List
+\labelwidthstring 00.00.0000
-\emph default
-For installation under Windows you first need to pick between a pre-compiled
- binary package, or installing the source package along with the Cygwin
- package.
- The binary package is the quickest to install, while the Cygwin package
- includes all of the open source power tools used to compile the complete
- SDCC source package in the Windows environment.
- If you are not familiar with the Unix command line environment, you may
- want to read the section on additional information for Windows users prior
- to your initial installation.
-\layout Subsubsection
+---disable-pic-port Excludes the PIC port
+\layout List
+\labelwidthstring 00.00.0000
-Windows Install Using a Binary Package
-\layout Enumerate
+---disable-xa51-port Excludes the XA51 port
+\layout List
+\labelwidthstring 00.00.0000
-Download the binary package and unpack it using your favorite unpacking
- tool (gunzip, WinZip, etc).
- This should unpack to a group of sub-directories.
- An example directory structure after unpacking is: c:
-\backslash
-usr
-\backslash
-local
-\backslash
-bin for the executables, c:
-\backslash
-usr
-\backslash
-local
-\backslash
-share
-\backslash
-sdcc
-\backslash
-include and c:
-\backslash
-usr
-\backslash
-local
-\backslash
-share
-\backslash
-sdcc
-\backslash
-lib for the include and libraries.
-\layout Enumerate
+---disable-ucsim Disables configuring and building of ucsim
+\layout List
+\labelwidthstring 00.00.0000
-Adjust your environment PATH to include the location of the bin directory.
- For example, make a setsdcc.bat file with the following: set PATH=c:
-\backslash
-usr
-\backslash
-local
-\backslash
-bin;%PATH%
-\layout Enumerate
+---disable-device-lib-build Disables automatically building device libraries
+\layout List
+\labelwidthstring 00.00.0000
-When you compile with sdcc, you may need to specify the location of the
- lib and include folders.
- For example, sdcc -I c:
-\backslash
-usr
-\backslash
-local
-\backslash
-share
-\backslash
-sdcc
-\backslash
-include -L c:
-\backslash
-usr
-\backslash
-local
-\backslash
-share
-\backslash
-sdcc
-\backslash
-lib
-\backslash
-small test.c
-\layout Subsubsection
+---disable-packihx Disables building packihx
+\layout List
+\labelwidthstring 00.00.0000
-Windows Install Using Cygwin
-\layout Enumerate
+---enable-libgc Use the Bohem memory allocator.
+ Lower runtime footprint.
+\layout Standard
+Furthermore the environment variables CC, CFLAGS, ...
+ the tools and their arguments can be influenced.
+ Please see `configure ---help` and the man/info pages of `configure` for
+ details.
+\newline
-\series medium
-Download and install the cygwin package from the redhat site
-\series default
+\newline
+The names of the standard libraries STD_LIB, STD_INT_LIB, STD_LONG_LIB,
+ STD_FP_LIB, STD_DS390_LIB, STD_XA51_LIB and the environment variables SDCC_DIR_
+NAME, SDCC_INCLUDE_NAME, SDCC_LIB_NAME are defined by `configure` too.
+ At the moment it's not possible to change the default settings (it was
+ simply never required.
+\newline
-\begin_inset LatexCommand \htmlurl{http://sources.redhat.com/cygwin/}
+\newline
+These configure options are compiled into the binaries, and can only be
+ changed by rerunning 'configure' and recompiling SDCC.
+ The configure options are written in
+\emph on
+italics
+\emph default
+ to distinguish them from run time environment variables (see section search
+ paths).
+\newline
+\newline
+The settings for
+\begin_inset Quotes sld
\end_inset
+Win32 builds
+\begin_inset Quotes srd
+\end_inset
-\series medium
-.
- Currently, this involved downloading a small install program which then
- automates downloading and installing
-\series default
-selected parts of
-\series medium
- the package
-\series default
- (a large 80M byte sized dowload for the whole thing)
-\series medium
-.
-
-\series default
-
+ are used by the SDCC team to build the official Win32 binaries.
+ The SDCC team uses Mingw32 to build the official Windows binaries, because
+ it's
\layout Enumerate
-
-\series medium
-Bring up a
-\series default
-Unix/Bash
-\series medium
-command line terminal from the Cygwin menu.
+open source,
\layout Enumerate
+a gcc compiler and last but not least
+\layout Enumerate
-\series medium
-Follow the instructions in the preceding Linux/Unix installation section.
-\layout Subsection
-
-Testing out the SDCC Compiler
+the binaries can be built by cross compiling on Sourceforge's compile farm.
\layout Standard
-The first thing you should do after installing your SDCC compiler is to
- see if it runs.
- Type
-\family sans
-\series bold
-"sdcc --version"
-\family default
-\series default
- at the prompt, and the program should run and tell you the version.
- If it doesn't run, or gives a message about not finding sdcc program, then
- you need to check over your installation.
- Make sure that the sdcc bin directory is in your executable search path
- defined by the PATH environment setting (see the Trouble-shooting section
- for suggestions).
- Make sure that the sdcc program is in the bin folder, if not perhaps something
- did not install correctly.
+See the examples, how to pass the Win32 settings to 'configure'.
+ The other Win32 builds using Borland, VC or whatever don't use 'configure',
+ but a header file sdcc_vc_in.h is the same as sdccconf.h built by 'configure'
+ for Win32.
\newline
\newline
-
-\series medium
-SDCC binaries are commonly installed in a directory arrangement like this:
-\series default
-
+These defaults are:
\newline
\newline
\begin_inset Tabular
-<lyxtabular version="2" rows="3" columns="2">
-<features rotate="false" islongtable="false" endhead="0" endfirsthead="0" endfoot="0" endlastfoot="0">
-<column alignment="left" valignment="top" leftline="true" rightline="false" width="" special="">
-<column alignment="left" valignment="top" leftline="true" rightline="true" width="" special="">
-<row topline="true" bottomline="true" newpage="false">
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
+<lyxtabular version="3" rows="8" columns="3">
+<features>
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" rightline="true" width="0in">
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
\begin_inset Text
\layout Standard
-/
-\series medium
-usr/local/bin
+Variable
\end_inset
</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="true" rotate="false" usebox="none" width="" special="">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
\begin_inset Text
\layout Standard
-
-\series medium
-Holds executables(sdcc, s51, aslink,
-\series default
-...
-\series medium
-)
+default
\end_inset
</cell>
-</row>
-<row topline="true" bottomline="false" newpage="false">
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
\begin_inset Text
\layout Standard
-/
-\series medium
-usr/local/share/sdcc/lib
+Win32 builds
\end_inset
</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="true" rotate="false" usebox="none" width="" special="">
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
\begin_inset Text
\layout Standard
-\series medium
-Holds common C
-\series default
-libraries
+\emph on
+PREFIX
\end_inset
</cell>
-</row>
-<row topline="true" bottomline="true" newpage="false">
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
\begin_inset Text
\layout Standard
-/
-\series medium
-usr/local/share/sdcc/include
+/usr/local
\end_inset
</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="true" rotate="false" usebox="none" width="" special="">
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
\begin_inset Text
\layout Standard
-\series medium
-Holds common C header files
+\backslash
+sdcc
\end_inset
</cell>
</row>
-</lyxtabular>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+\emph on
+EXEC_PREFIX
\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\newline
-\newline
+\emph on
+$PREFIX
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\series medium
-Make sure the compiler works on a very simple example.
- Type in the following test.c program using your favorite editor:
-\series default
+\layout Standard
-\newline
\emph on
+$PREFIX
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\newline
-
-\family typewriter
-\emph default
-int test(int t) {
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-return t+3;
-\newline
-}
-\family default
+\layout Standard
-\newline
\emph on
+BINDIR
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\newline
+\layout Standard
-\series medium
+
+\emph on
+$EXECPREFIX
\emph default
-Compile this using the following command:
-\family sans
-\series bold
-"sdcc -c test.c".
+/bin
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\family default
-\series default
-
-\series medium
-If all goes well, the compiler will generate a test.asm and test.rel file.
- Congratulations, you've just compiled your first program with SDCC.
- We used the -c option to tell SDCC not to link the generated code, just
- to keep things simple for this step.
-\series default
+\layout Standard
-\newline
-\newline
+\emph on
+$EXECPREFIX
+\emph default
-\series medium
-The next step is to try it with the linker.
- Type in
-\family sans
-\series bold
-"sdcc test.c
-\family default
-\series default
-"
-\series medium
-.
- If all goes well the compiler will link with the libraries and produce
- a test.ihx output file.
- If this step fails
-\series default
-
-\series medium
-(no test.ihx, and the linker generates warnings), then the problem is most
- likely that sdcc cannot find the
-\series default
-/
-\series medium
-usr/local/share/sdcc/lib directory
-\series default
-
-\series medium
-(see the Install trouble-shooting section for suggestions).
-\series default
+\backslash
+bin
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\newline
+\layout Standard
-\newline
-\series medium
-The final test is to ensure sdcc can use the
-\series default
-standard
-\series medium
- header files and libraries.
- Edit test.c and change it to the following:
-\series default
+\emph on
+DATADIR
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\newline
+\layout Standard
-\newline
-#include <string.h>
-\newline
-main() {
-\newline
-\family typewriter
-char str1[10];
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-strcpy(str1, "testing");
-\newline
-}
-\newline
+\emph on
+$PREFIX
+\emph default
+/share
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\newline
+\layout Standard
-\family default
-\series medium
-Compile this by typing
-\family sans
-\series bold
-"sdcc test.c"
-\family default
-\series medium
-.
- This should generate a test.ihx output file, and it should give no warnings
- such as not finding the string.h file.
- If it cannot find the string.h file, then the problem is that sdcc cannot
- find the /usr/local/share/sdcc/include directory
-\series default
-
-\series medium
-(see the Install trouble-shooting section for suggestions).
-\layout Subsection
-Install Trouble-shooting
-\layout Subsubsection
+\emph on
+$PREFIX
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-SDCC cannot find libraries or header files.
\layout Standard
-The default installation assumes the libraries and header files are located
- at
-\begin_inset Quotes eld
-\end_inset
-/usr/local/share/sdcc/lib
-\begin_inset Quotes erd
+\emph on
+DOCDIR
\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
- and
-\begin_inset Quotes eld
-\end_inset
+\layout Standard
-/usr/local/share/sdcc/include
-\begin_inset Quotes erd
-\end_inset
-.
- An alternative is to specify these locations as compiler options like this:
-
-\family sans
-\series bold
-"sdcc\SpecialChar ~
--L\SpecialChar ~
-/usr/local/sdcc/lib/small\SpecialChar ~
--I\SpecialChar ~
-/usr/local/sdcc/include\SpecialChar ~
-test.c"
-\family default
-\series default
-.
-\layout Subsubsection
+\emph on
+$DATADIR
+\emph default
+/sdcc/doc
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-SDCC does not compile correctly.
\layout Standard
-A thing to try is starting from scratch by unpacking the .tgz source package
- again in an empty directory.
- Confure it again and build like:
-\newline
-
-\newline
-\family sans
-\series bold
-make 2&>1 | tee make.log
-\family default
-\series default
+\emph on
+$DATADIR
+\emph default
-\newline
+\backslash
+doc
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\newline
-After this you can review the make.log file to locate the problem.
- Or a relevant part of this be attached to an email that could be helpful
- when requesting help from the mailing list.
-\layout Subsubsection
+\layout Standard
-What the
-\begin_inset Quotes sld
-\end_inset
-./configure
-\begin_inset Quotes srd
+\emph on
+INCLUDE_DIR_SUFFIX
\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
- does
\layout Standard
-The
-\begin_inset Quotes sld
+sdcc/include
\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-./configure
-\begin_inset Quotes srd
+\layout Standard
+
+include
\end_inset
+</cell>
+</row>
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
- command is a script that analyzes your system and performs some configuration
- to ensure the source package compiles on your system.
- It will take a few minutes to run, and will compile a few tests to determine
- what compiler features are installed.
-\layout Subsubsection
+\layout Standard
-What the
-\begin_inset Quotes sld
-\end_inset
-make
-\begin_inset Quotes srd
+\emph on
+LIB_DIR_SUFFIX
\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
- does.
\layout Standard
-This runs the GNU make tool, which automatically compiles all the source
- packages into the final installed binary executables.
-\layout Subsubsection
-
-What the
-\begin_inset Quotes sld
-\end_inset
-
-make install
-\begin_inset Quotes erd
+sdcc/lib
\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
- command does.
\layout Standard
-This will install the compiler, other executables and libraries in to the
- appropriate system directories.
- The default is to copy the executables to /usr/local/bin and the libraries
- and header files to /usr/local/share/sdcc/lib and /usr/local/share/sdcc/include.
-\layout Subsection
+lib
+\end_inset
+</cell>
+</row>
+</lyxtabular>
-Additional Information for Windows Users
-\layout Standard
+\end_inset
-\emph on
-<pending: is this up to date?>
\newline
\newline
-\emph default
-The standard method of installing on a Unix system involves compiling the
- source package.
- This is easily done under Unix, but under Windows it can be a more difficult
- process.
- The Cygwin is a large package to download, and the compilation runs considerabl
-y slower under Windows due to the overhead of the Cygwin tool set.
- An alternative is to install a pre-compiled Windows binary package.
- There are various trade-offs between each of these methods.
-
-\layout Standard
-
-The Cygwin package allows a Windows user to run a Unix command line interface
- (bash shell) and also implements a Unix like file system on top of Windows.
- Included are many of the famous GNU software development tools which can
- augment the SDCC compiler.This is great if you have some experience with
- Unix command line tools and file system conventions, if not you may find
- it easier to start by installing a binary Windows package.
- The binary packages work with the Windows file system conventions.
-\layout Subsubsection
-
-Getting started with Cygwin
-\layout Standard
+\newline
+'configure' also computes relative paths.
+ This is needed for full relocatability of a binary package and to complete
+ search paths (see section search paths below):
+\newline
+
+\newline
-SDCC is typically distributed as a tarred/gzipped file (.tgz).
- This is a packed file similar to a .zip file.
- Cygwin includes the tools you will need to unpack the SDCC distribution
- (tar and gzip).
- To unpack it, simply follow the instructions under the Linux/Unix install
- section.
- Before you do this you need to learn how to start a cygwin shell and some
- of the basic commands used to move files, change directory, run commands
- and so on.
- The change directory command is
-\family sans
-\series bold
+\begin_inset Tabular
+<lyxtabular version="3" rows="4" columns="3">
+<features>
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" rightline="true" width="0in">
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\begin_inset Quotes eld
-\end_inset
+\layout Standard
-cd
-\begin_inset Quotes erd
+Variable (computed)
\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\family default
-\series default
-, the move command is
-\family sans
-\series bold
-
-\begin_inset Quotes eld
+default
\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-mv
-\begin_inset Quotes erd
+\layout Standard
+
+Win32 builds
\end_inset
+</cell>
+</row>
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\family default
-\series default
-.
- To print the current working directory, type
-\family sans
-\series bold
-\begin_inset Quotes eld
+\emph on
+BIN2DATA_DIR
\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-pwd
-\begin_inset Quotes erd
-\end_inset
+\layout Standard
+../share
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\family default
-\series default
-.
- To make a directory, use
-\family sans
-\series bold
+\layout Standard
-\begin_inset Quotes eld
-\end_inset
+..
+\backslash
-mkdir
-\begin_inset Quotes erd
\end_inset
+</cell>
+</row>
+<row bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-
-\family default
-\series default
-.
\layout Standard
-There are some basic differences between Unix and Windows file systems you
- should understand.
- When you type in directory paths, Unix and the Cygwin bash prompt uses
- forward slashes '/' between directories while Windows traditionally uses
- '
-\backslash
-' backward slashes.
- So when you work at the Cygwin bash prompt, you will need to use the forward
- '/' slashes.
- Unix does not have a concept of drive letters, such as
-\begin_inset Quotes eld
-\end_inset
-c:
-\begin_inset Quotes eld
+\emph on
+PREFIX2BIN_DIR
\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-, instead all files systems attach and appear as directories.
-\layout Subsubsection
-
-Running SDCC as Native Compiled Executables
\layout Standard
-If you use the pre-compiled binaries, the install directories for the libraries
- and header files may need to be specified on the sdcc command line like
- this:
-\family sans
-\series bold
-"sdcc -L c:
-\backslash
-usr
-\backslash
-local
-\backslash
-sdcc
-\backslash
-lib
-\backslash
-small -I c:
-\backslash
-usr
-\backslash
-local
-\backslash
-sdcc
-\backslash
-include test.c"
-\family default
-\series default
- if you are running outside of a Unix bash shell.
+bin
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
\layout Standard
-If you have successfully installed and compiled SDCC with the Cygwin package,
- it is possible to compile into native .exe files by using the additional
- makefiles included for this purpose.
- For example, with the Borland 32-bit compiler you would run
-\family sans
-\series bold
-"make -f Makefile.bcc"
-\family default
-\series default
-.
- A command line version of the Borland 32-bit compiler can be downloaded
- from the Inprise web site.
-\layout Subsection
+bin
+\end_inset
+</cell>
+</row>
+<row bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-SDCC on Other Platforms
-\layout Itemize
+\layout Standard
-\series bold
-FreeBSD and other non-GNU Unixes
-\series default
-- Make sure the GNU make is installed as the default make tool.
-\layout Itemize
+\emph on
+PREFIX2DATA_DIR
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-SDCC has been ported to run under a variety of operating systems and processors.
- If you can run GNU GCC/make then chances are good SDCC can be compiled
- and run on your system.
-\layout Subsection
+\layout Standard
+
+share/sdcc
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-Advanced Install Options
\layout Standard
-The
-\begin_inset Quotes eld
\end_inset
+</cell>
+</row>
+</lyxtabular>
-configure
-\begin_inset Quotes erd
\end_inset
- command has several options.
- The most commonly used option is --prefix=<directory name>, where <directory
- name> is the final location for the sdcc executables and libraries, (default
- location is /usr/local).
- The installation process will create the following directory structure
- under the <directory name> specified (if they do not already exist).
-
-\newline
-\newline
-bin/ - binary exectables (add to PATH environment variable)
-\newline
-bin/share/
-\newline
-bin/share/sdcc/include/ - include header files
-\newline
-bin/share/sdcc/lib/
-\newline
-bin/share/sdcc/lib/small/ - Object & library files for small model library
-\newline
-bin/share/sdcc/lib/large/ - Object & library files for large model library
-\newline
-bin/share/sdcc/lib/ds390/ - Object & library files forDS80C390 library
\newline
\newline
-The command
-\family sans
-\series bold
+Examples:
+\layout LyX-Code
-\begin_inset Quotes sld
+./configure
+\layout LyX-Code
+
+./configure ---prefix=
+\begin_inset Quotes srd
\end_inset
-./configure --prefix=/usr/local
-\begin_inset Quotes erd
+/usr/bin
+\begin_inset Quotes srd
\end_inset
-
-\family default
-\series default
-will configure the compiler to be installed in directory /usr/local.
-\layout Subsection
+ ---datadir=
+\begin_inset Quotes srd
+\end_inset
-Components of SDCC
-\layout Standard
+/usr/share
+\begin_inset Quotes srd
+\end_inset
-SDCC is not just a compiler, but a collection of tools by various developers.
- These include linkers, assemblers, simulators and other components.
- Here is a summary of some of the components.
- Note that the included simulator and assembler have separate documentation
- which you can find in the source package in their respective directories.
- As SDCC grows to include support for other processors, other packages from
- various developers are included and may have their own sets of documentation.
-\newline
-\newline
-You might want to look at the files which are installed in <installdir>.
- At the time of this writing, we find the following programs:
-\newline
-
-\newline
-In <installdir>/bin:
-\layout Itemize
+\layout LyX-Code
-sdcc - The compiler.
-\layout Itemize
+./configure ---disable-avr-port ---disable-xa51-port
+\layout Standard
-sdcpp - The C preprocessor.
-\layout Itemize
+To crosscompile on linux for Mingw32 (see also 'sdcc/support/scripts/sdcc_mingw3
+2'):
+\layout LyX-Code
-asx8051 - The assembler for 8051 type processors.
-\layout Itemize
+./configure
+\backslash
-as-z80
-\series bold
-,
-\series default
-as-gbz80 - The Z80 and GameBoy Z80 assemblers.
-\layout Itemize
+\layout LyX-Code
-aslink -The linker for 8051 type processors.
-\layout Itemize
+ CC=
+\begin_inset Quotes srd
+\end_inset
-link-z80
-\series bold
-,
-\series default
-link-gbz80 - The Z80 and GameBoy Z80 linkers.
-\layout Itemize
+i586-mingw32msvc-gcc
+\begin_inset Quotes srd
+\end_inset
-s51 - The ucSim 8051 simulator.
-\layout Itemize
+ CXX=
+\begin_inset Quotes srd
+\end_inset
-sdcdb - The source debugger.
-\layout Itemize
+i586-mingw32msvc-g++
+\begin_inset Quotes srd
+\end_inset
-packihx - A tool to pack Intel hex files.
-\layout Standard
+
+\backslash
-In <installdir>/share/sdcc/include
-\layout Itemize
+\layout LyX-Code
-the include files
-\layout Standard
+ RANLIB=
+\begin_inset Quotes srd
+\end_inset
-In <installdir>/share/sdcc/lib
-\layout Itemize
+i586-mingw32msvc-ranlib
+\begin_inset Quotes srd
+\end_inset
-the sources of the runtime library and the subdirs small large and ds390
- with the precompiled relocatables.
-\layout Standard
+
+\backslash
-In <installdir>/share/sdcc/doc
-\layout Itemize
+\layout LyX-Code
-the documentation
-\layout Standard
+ STRIP=
+\begin_inset Quotes srd
+\end_inset
-As development for other processors proceeds, this list will expand to include
- executables to support processors like AVR, PIC, etc.
-\layout Subsubsection
+i586-mingw32msvc-strip
+\begin_inset Quotes srd
+\end_inset
-sdcc - The Compiler
-\layout Standard
-
-This is the actual compiler, it in turn uses the c-preprocessor and invokes
- the assembler and linkage editor.
-\layout Subsubsection
+
+\backslash
-sdcpp (C-Preprocessor)
-\layout Standard
+\layout LyX-Code
-The preprocessor is a modified version of the GNU preprocessor.
- The C preprocessor is used to pull in #include sources, process #ifdef
- statements, #defines and so on.
-\layout Subsubsection
+ ---prefix=
+\begin_inset Quotes srd
+\end_inset
-asx8051, as-z80, as-gbz80, aslink, link-z80, link-gbz80 (The Assemblers
- and Linkage Editors)
-\layout Standard
+/sdcc
+\begin_inset Quotes srd
+\end_inset
-This is retargettable assembler & linkage editor, it was developed by Alan
- Baldwin.
- John Hartman created the version for 8051, and I (Sandeep) have made some
- enhancements and bug fixes for it to work properly with the SDCC.
-\layout Subsubsection
+
+\backslash
-s51 - Simulator
-\layout Standard
+\layout LyX-Code
-S51 is a freeware, opensource simulator developed by Daniel Drotos (
-\begin_inset LatexCommand \url{mailto:drdani@mazsola.iit.uni-miskolc.hu}
+ ---datadir=
+\begin_inset Quotes srd
+\end_inset
+/sdcc
+\begin_inset Quotes srd
\end_inset
-).
- The simulator is built as part of the build process.
- For more information visit Daniel's website at:
-\begin_inset LatexCommand \url{http://mazsola.iit.uni-miskolc.hu/~drdani/embedded/s51}
+
+\backslash
+\layout LyX-Code
+
+ docdir=
+\begin_inset Quotes srd
\end_inset
- .
-\layout Subsubsection
+/sdcc/doc
+\begin_inset Quotes srd
+\end_inset
-sdcdb - Source Level Debugger
-\layout Standard
+
+\backslash
-Sdcdb is the companion source level debugger.
- The current version of the debugger uses Daniel's Simulator S51, but can
- be easily changed to use other simulators.
-\layout Section
+\layout LyX-Code
-Using SDCC
-\layout Subsection
+ include_dir_suffix=
+\begin_inset Quotes srd
+\end_inset
-Compiling
-\layout Subsubsection
+include
+\begin_inset Quotes srd
+\end_inset
-Single Source File Projects
-\layout Standard
+
+\backslash
-For single source file 8051 projects the process is very simple.
- Compile your programs with the following command
-\family sans
-\series bold
-"sdcc sourcefile.c".
+\layout LyX-Code
-\family default
-\series default
- This will compile, assemble and link your source file.
- Output files are as follows
-\newline
+ lib_dir_suffix=
+\begin_inset Quotes srd
+\end_inset
-\newline
-sourcefile.asm - Assembler source file created by the compiler
-\newline
-sourcefile.lst - Assembler listing file created by the Assembler
-\newline
-sourcefile.rst - Assembler listing file updated with linkedit information,
- created by linkage editor
-\newline
-sourcefile.sym - symbol listing for the sourcefile, created by the assembler
-\newline
-sourcefile.rel - Object file created by the assembler, input to Linkage editor
-\newline
-sourcefile.map - The memory map for the load module, created by the Linker
-\newline
-sourcefile.ihx - The load module in Intel hex format (you can select the
- Motorola S19 format with --out-fmt-s19)
-\newline
-sourcefile.cdb - An optional file (with --debug) containing debug information
-\newline
+lib
+\begin_inset Quotes srd
+\end_inset
-\layout Subsubsection
+
+\backslash
-Projects with Multiple Source Files
-\layout Standard
+\layout LyX-Code
-SDCC can compile only ONE file at a time.
- Let us for example assume that you have a project containing the following
- files:
-\newline
+ sdccconf_h_dir_separator=
+\begin_inset Quotes srd
+\end_inset
-\newline
-foo1.c (contains some functions)
-\newline
-foo2.c (contains some more functions)
-\newline
-foomain.c (contains more functions and the function main)
-\newline
-\size footnotesize
+\backslash
-\newline
+\backslash
-\size default
-The first two files will need to be compiled separately with the commands:
-\size footnotesize
-
-\size default
+\backslash
-\newline
+\backslash
-\newline
+\begin_inset Quotes srd
+\end_inset
-\family sans
-\series bold
-sdcc\SpecialChar ~
--c\SpecialChar ~
-foo1.c
-\family default
-\series default
-\size footnotesize
+
+\backslash
-\newline
+\layout LyX-Code
-\family sans
-\series bold
-\size default
-sdcc\SpecialChar ~
--c\SpecialChar ~
-foo2.c
-\family default
-\series default
+ ---disable-device-lib-build
+\backslash
-\newline
+\layout LyX-Code
-\newline
-Then compile the source file containing the
-\emph on
-main()
-\emph default
- function and link the files together with the following command:
-\newline
+ ---disable-ucsim
+\backslash
-\newline
+\layout LyX-Code
-\family sans
-\series bold
-sdcc\SpecialChar ~
-foomain.c\SpecialChar ~
-foo1.rel\SpecialChar ~
-foo2.rel
-\family default
-\series default
+ ---host=i586-mingw32msvc ---build=unknown-unknown-linux-gnu
+\layout Standard
-\newline
+To
+\begin_inset Quotes sld
+\end_inset
-\newline
-Alternatively,
-\emph on
-foomain.c
-\emph default
-can be separately compiled as well:
-\family sans
-\series bold
+cross
+\begin_inset Quotes srd
+\end_inset
-\newline
+compile on Cygwin for Mingw32(see also sdcc/support/scripts/sdcc_cygwin_mingw32)
+:
+\layout LyX-Code
-\newline
-sdcc\SpecialChar ~
--c\SpecialChar ~
-foomain.c
-\newline
-sdcc foomain.rel foo1.rel foo2.rel
-\newline
+./configure -C
+\backslash
-\newline
+\layout LyX-Code
+
+ CFLAGS=
+\begin_inset Quotes srd
+\end_inset
+
+-mno-cygwin -O2
+\begin_inset Quotes srd
+\end_inset
-\family default
-\series default
-The file containing the
-\emph on
-main()
-\emph default
- function
-\emph on
-\emph default
-\noun on
-must
-\noun default
- be the
-\noun on
-first
-\noun default
- file specified in the command line, since the linkage editor processes
- file in the order they are presented to it.
-\layout Subsubsection
+\backslash
-Projects with Additional Libraries
-\layout Standard
+\layout LyX-Code
-Some reusable routines may be compiled into a library, see the documentation
- for the assembler and linkage editor (which are in <installdir>/share/sdcc/doc)
- for how to create a
-\emph on
-.lib
-\emph default
- library file.
- Libraries created in this manner can be included in the command line.
- Make sure you include the -L <library-path> option to tell the linker where
- to look for these files if they are not in the current directory.
- Here is an example, assuming you have the source file
-\emph on
-foomain.c
-\emph default
- and a library
-\emph on
- foolib.lib
-\emph default
- in the directory
-\emph on
-mylib
-\emph default
- (if that is not the same as your current project):
-\newline
+ LDFLAGS=
+\begin_inset Quotes srd
+\end_inset
-\newline
+-mno-cygwin
+\begin_inset Quotes srd
+\end_inset
-\family sans
-\series bold
-sdcc foomain.c foolib.lib -L mylib
-\newline
+
+\backslash
-\newline
+\layout LyX-Code
-\family default
-\series default
-Note here that
-\emph on
- mylib
-\emph default
- must be an absolute path name.
-\newline
+ ---prefix=
+\begin_inset Quotes srd
+\end_inset
-\newline
-The most efficient way to use libraries is to keep seperate modules in seperate
- source files.
- The lib file now should name all the modules.rel files.
- For an example see the standard library file
-\emph on
-libsdcc.lib
-\emph default
- in the directory <installdir>/share/lib/small.
-\layout Subsection
-
-Command Line Options
-\layout Subsubsection
-
-Processor Selection Options
-\layout List
-\labelwidthstring 00.00.0000
-
-
-\series bold
--mmcs51
-\series default
- Generate code for the MCS51 (8051) family of processors.
- This is the default processor target.
-\layout List
-\labelwidthstring 00.00.0000
+/sdcc
+\begin_inset Quotes srd
+\end_inset
+
+\backslash
-\series bold
--mds390
-\series default
- Generate code for the DS80C390 processor.
-\layout List
-\labelwidthstring 00.00.0000
+\layout LyX-Code
+ ---datadir=
+\begin_inset Quotes srd
+\end_inset
-\series bold
--mz80
-\series default
- Generate code for the Z80 family of processors.
-\layout List
-\labelwidthstring 00.00.0000
+/sdcc
+\begin_inset Quotes srd
+\end_inset
+
+\backslash
-\series bold
--mgbz80
-\series default
- Generate code for the GameBoy Z80 processor.
-\layout List
-\labelwidthstring 00.00.0000
+\layout LyX-Code
+ docdir=
+\begin_inset Quotes srd
+\end_inset
-\series bold
--mavr
-\series default
- Generate code for the Atmel AVR processor(In development, not complete).
-\layout List
-\labelwidthstring 00.00.0000
+/sdcc/doc
+\begin_inset Quotes srd
+\end_inset
+
+\backslash
-\series bold
--mpic14
-\series default
- Generate code for the PIC 14-bit processors(In development, not complete).
-\layout List
-\labelwidthstring 00.00.0000
+\layout LyX-Code
+ include_dir_suffix=
+\begin_inset Quotes srd
+\end_inset
-\series bold
--mtlcs900h
-\series default
- Generate code for the Toshiba TLCS-900H processor(In development, not complete).
-\layout Subsubsection
+include
+\begin_inset Quotes srd
+\end_inset
-Preprocessor Options
-\layout List
-\labelwidthstring 00.00.0000
+
+\backslash
+\layout LyX-Code
-\series bold
--I<path>
-\series default
- The additional location where the pre processor will look for <..h> or
-\begin_inset Quotes eld
+ lib_dir_suffix=
+\begin_inset Quotes srd
\end_inset
-..h
-\begin_inset Quotes erd
+lib
+\begin_inset Quotes srd
\end_inset
- files.
-\layout List
-\labelwidthstring 00.00.0000
+
+\backslash
+\layout LyX-Code
-\series bold
--D<macro[=value]>
-\series default
- Command line definition of macros.
- Passed to the pre processor.
-\layout List
-\labelwidthstring 00.00.0000
+ sdccconf_h_dir_separator=
+\begin_inset Quotes srd
+\end_inset
-\series bold
--M
-\series default
- Tell the preprocessor to output a rule suitable for make describing the
- dependencies of each object file.
- For each source file, the preprocessor outputs one make-rule whose target
- is the object file name for that source file and whose dependencies are
- all the files `#include'd in it.
- This rule may be a single line or may be continued with `
\backslash
-'-newline if it is long.
- The list of rules is printed on standard output instead of the preprocessed
- C program.
- `-M' implies `-E'.
-\layout List
-\labelwidthstring 00.00.0000
+\backslash
-\series bold
--C
-\series default
- Tell the preprocessor not to discard comments.
- Used with the `-E' option.
-\layout List
-\labelwidthstring 00.00.0000
+\backslash
+\backslash
-\series bold
--MM
-\size large
-\bar under
-
-\series default
-\size default
-\bar default
-Like `-M' but the output mentions only the user header files included with
- `#include
-\begin_inset Quotes eld
+\begin_inset Quotes srd
\end_inset
-file"'.
- System header files included with `#include <file>' are omitted.
-\layout List
-\labelwidthstring 00.00.0000
+
+\backslash
+\layout LyX-Code
-\series bold
--Aquestion(answer)
-\series default
- Assert the answer answer for question, in case it is tested with a preprocessor
- conditional such as `#if #question(answer)'.
- `-A-' disables the standard assertions that normally describe the target
- machine.
-\layout List
-\labelwidthstring 00.00.0000
+ ---disable-ucsim
+\layout Standard
+'configure' is quite slow on Cygwin (at least on windows before Win2000/XP).
+ The option '--C' turns on caching, which gives a little bit extra speed.
+ However if options are changed, it can be necessary to delete the config.cache
+ file.
+\layout Subsection
-\series bold
--Aquestion
-\series default
- (answer) Assert the answer answer for question, in case it is tested with
- a preprocessor conditional such as `#if #question(answer)'.
- `-A-' disables the standard assertions that normally describe the target
- machine.
-\layout List
-\labelwidthstring 00.00.0000
+Install paths
+\begin_inset LatexCommand \index{Install paths}
+\end_inset
-\series bold
--Umacro
-\series default
- Undefine macro macro.
- `-U' options are evaluated after all `-D' options, but before any `-include'
- and `-imacros' options.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
-\series bold
--dM
-\series default
- Tell the preprocessor to output only a list of the macro definitions that
- are in effect at the end of preprocessing.
- Used with the `-E' option.
-\layout List
-\labelwidthstring 00.00.0000
+1.
+ Binary files (preprocessor, assembler and linker)
+\layout Standard
-\series bold
--dD
-\series default
- Tell the preprocessor to pass all macro definitions into the output, in
- their proper sequence in the rest of the output.
-\layout List
-\labelwidthstring 00.00.0000
+\begin_inset Tabular
+<lyxtabular version="3" rows="2" columns="3">
+<features>
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" rightline="true" width="0in">
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
--dN
-\size large
-\bar under
-
-\series default
-\size default
-\bar default
-Like `-dD' except that the macro arguments and contents are omitted.
- Only `#define name' is included in the output.
-\layout Subsubsection
+Path
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-Linker Options
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+default
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\series bold
--L\SpecialChar ~
---lib-path
-\bar under
-
-\series default
-\bar default
-<absolute path to additional libraries> This option is passed to the linkage
- editor's additional libraries search path.
- The path name must be absolute.
- Additional library files may be specified in the command line.
- See section Compiling programs for more details.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+Win32 builds
+\end_inset
+</cell>
+</row>
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\series bold
---xram-loc
-\series default
-<Value> The start location of the external ram, default value is 0.
- The value entered can be in Hexadecimal or Decimal format, e.g.: --xram-loc
- 0x8000 or --xram-loc 32768.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
-\series bold
---code-loc
-\series default
-<Value> The start location of the code segment, default value 0.
- Note when this option is used the interrupt vector table is also relocated
- to the given address.
- The value entered can be in Hexadecimal or Decimal format, e.g.: --code-loc
- 0x8000 or --code-loc 32768.
-\layout List
-\labelwidthstring 00.00.0000
+\emph on
+$EXEC_PREFIX
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
---stack-loc
-\series default
-<Value> The initial value of the stack pointer.
- The default value of the stack pointer is 0x07 if only register bank 0
- is used, if other register banks are used then the stack pointer is initialized
- to the location above the highest register bank used.
- eg.
- if register banks 1 & 2 are used the stack pointer will default to location
- 0x18.
- The value entered can be in Hexadecimal or Decimal format, eg.
- --stack-loc 0x20 or --stack-loc 32.
- If all four register banks are used the stack will be placed after the
- data segment (equivalent to --stack-after-data)
-\layout List
-\labelwidthstring 00.00.0000
+/usr/local/bin
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
---stack-after-data
-\series default
- This option will cause the stack to be located in the internal ram after
- the data segment.
-\layout List
-\labelwidthstring 00.00.0000
+\backslash
+sdcc
+\backslash
+bin
+\end_inset
+</cell>
+</row>
+</lyxtabular>
-\series bold
---data-loc
-\series default
-<Value> The start location of the internal ram data segment, the default
- value is 0x30.The value entered can be in Hexadecimal or Decimal format,
- eg.
- --data-loc 0x20 or --data-loc 32.
-\layout List
-\labelwidthstring 00.00.0000
+\end_inset
+
+\newline
-\series bold
---idata-loc
-\series default
-<Value> The start location of the indirectly addressable internal ram, default
- value is 0x80.
- The value entered can be in Hexadecimal or Decimal format, eg.
- --idata-loc 0x88 or --idata-loc 136.
-\layout List
-\labelwidthstring 00.00.0000
+\newline
+2.
+ Include files
+\layout Standard
-\series bold
---out-fmt-ihx
-\bar under
-
-\series default
-\bar default
-The linker output (final object code) is in Intel Hex format.
- (This is the default option).
-\layout List
-\labelwidthstring 00.00.0000
+\begin_inset Tabular
+<lyxtabular version="3" rows="2" columns="3">
+<features>
+<column alignment="block" valignment="top" leftline="true" width="1.6in">
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="center" valignment="top" leftline="true" rightline="true" width="0in">
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
---out-fmt-s19
-\bar under
-
-\series default
-\bar default
-The linker output (final object code) is in Motorola S19 format.
-\layout Subsubsection
+Path
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-MCS51 Options
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+
+default
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
---model-large
-\series default
- Generate code for Large model programs see section Memory Models for more
- details.
- If this option is used all source files in the project should be compiled
- with this option.
- In addition the standard library routines are compiled with small model,
- they will need to be recompiled.
-\layout List
-\labelwidthstring 00.00.0000
+Win32 builds
+\end_inset
+</cell>
+</row>
+<row topline="true" bottomline="true">
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
-\series bold
---model-small
-\series default
-\size large
\emph on
-
-\size default
-\emph default
-Generate code for Small Model programs see section Memory Models for more
- details.
- This is the default model.
-\layout Subsubsection
+$DATADIR/
+\newline
+$INCLUDE_DIR_SUFFIX
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-DS390 Options
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+/usr/local/share/sdcc/include
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\series bold
---model-flat24
-\series default
-\size large
-\emph on
-
-\size default
-\emph default
-Generate 24-bit flat mode code.
- This is the one and only that the ds390 code generator supports right now
- and is default when using
-\emph on
--mds390
-\emph default
-.
- See section Memory Models for more details.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
-\series bold
---stack-10bit
-\series default
- Generate code for the 10 bit stack mode of the Dallas DS80C390 part.
- This is the one and only that the ds390 code generator supports right now
- and is default when using
-\emph on
--mds390
-\emph default
-.
- In this mode, the stack is located in the lower 1K of the internal RAM,
- which is mapped to 0x400000.
- Note that the support is incomplete, since it still uses a single byte
- as the stack pointer.
- This means that only the lower 256 bytes of the potential 1K stack space
- will actually be used.
- However, this does allow you to reclaim the precious 256 bytes of low RAM
- for use for the DATA and IDATA segments.
- The compiler will not generate any code to put the processor into 10 bit
- stack mode.
- It is important to ensure that the processor is in this mode before calling
- any re-entrant functions compiled with this option.
- In principle, this should work with the
-\emph on
---stack-auto
-\emph default
- option, but that has not been tested.
- It is incompatible with the
-\emph on
---xstack
-\emph default
- option.
- It also only makes sense if the processor is in 24 bit contiguous addressing
- mode (see the
-\emph on
---model-flat24 option
-\emph default
-).
-\layout Subsubsection
+\backslash
+sdcc
+\backslash
+include
+\end_inset
+</cell>
+</row>
+</lyxtabular>
-Optimization Options
-\layout List
-\labelwidthstring 00.00.0000
+\end_inset
-\series bold
---nogcse
-\series default
- Will not do global subexpression elimination, this option may be used when
- the compiler creates undesirably large stack/data spaces to store compiler
- temporaries.
- A warning message will be generated when this happens and the compiler
- will indicate the number of extra bytes it allocated.
- It recommended that this option NOT be used, #pragma\SpecialChar ~
-NOGCSE can be used
- to turn off global subexpression elimination for a given function only.
-\layout List
-\labelwidthstring 00.00.0000
+\newline
+\newline
+3.
+ Library files (the
+\shape italic
+model
+\shape default
+ is auto-appended by the compiler, e.g.
+ small, large, z80, ds390 etc.)
+\layout Standard
-\series bold
---noinvariant
-\series default
- Will not do loop invariant optimizations, this may be turned off for reasons
- explained for the previous option.
- For more details of loop optimizations performed see section Loop Invariants.It
- recommended that this option NOT be used, #pragma\SpecialChar ~
-NOINVARIANT can be used
- to turn off invariant optimizations for a given function only.
-\layout List
-\labelwidthstring 00.00.0000
+\begin_inset Tabular
+<lyxtabular version="3" rows="2" columns="3">
+<features>
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" rightline="true" width="0in">
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\series bold
---noinduction
-\series default
- Will not do loop induction optimizations, see section strength reduction
- for more details.It is recommended that this option is NOT used, #pragma\SpecialChar ~
-NOINDUCT
-ION can be used to turn off induction optimizations for a given function
- only.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+Path
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\series bold
---nojtbound
-\size large
-\bar under
-
-\series default
-\size default
-\bar default
- Will not generate boundary condition check when switch statements are implement
-ed using jump-tables.
- See section Switch Statements for more details.
- It is recommended that this option is NOT used, #pragma\SpecialChar ~
-NOJTBOUND can be
- used to turn off boundary checking for jump tables for a given function
- only.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+default
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\series bold
---noloopreverse
-\series default
-\size large
-
-\size default
-Will not do loop reversal optimization.
-\layout Subsubsection
+\layout Standard
-Other Options
-\layout List
-\labelwidthstring 00.00.0000
+Win32 builds
+\end_inset
+</cell>
+</row>
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
--c\SpecialChar ~
---compile-only
-\series default
- will compile and assemble the source, but will not call the linkage editor.
-\layout List
-\labelwidthstring 00.00.0000
+\emph on
+$DATADIR/$LIB_DIR_SUFFIX
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\series bold
--E
-\series default
- Run only the C preprocessor.
- Preprocess all the C source files specified and output the results to standard
- output.
-\layout List
-\labelwidthstring 00.00.0000
-
+\layout Standard
-\series bold
---stack-auto
-\series default
-\size large
-\emph on
-
-\size default
-\emph default
-All functions in the source file will be compiled as
-\emph on
-reentrant
-\emph default
-, i.e.
- the parameters and local variables will be allocated on the stack.
- see section Parameters and Local Variables for more details.
- If this option is used all source files in the project should be compiled
- with this option.
-
-\layout List
-\labelwidthstring 00.00.0000
+/usr/local/share/sdcc/lib
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
---xstack
-\series default
- Uses a pseudo stack in the first 256 bytes in the external ram for allocating
- variables and passing parameters.
- See section on external stack for more details.
-\layout List
-\labelwidthstring 00.00.0000
+\backslash
+sdcc
+\backslash
+lib
+\end_inset
+</cell>
+</row>
+</lyxtabular>
-\series bold
---callee-saves function1[,function2][,function3]....
+\end_inset
-\series default
- The compiler by default uses a caller saves convention for register saving
- across function calls, however this can cause unneccessary register pushing
- & popping when calling small functions from larger functions.
- This option can be used to switch the register saving convention for the
- function names specified.
- The compiler will not save registers when calling these functions, no extra
- code will be generated at the entry & exit for these functions to save
- & restore the registers used by these functions, this can SUBSTANTIALLY
- reduce code & improve run time performance of the generated code.
- In the future the compiler (with interprocedural analysis) will be able
- to determine the appropriate scheme to use for each function call.
- DO NOT use this option for built-in functions such as _muluint..., if this
- option is used for a library function the appropriate library function
- needs to be recompiled with the same option.
- If the project consists of multiple source files then all the source file
- should be compiled with the same --callee-saves option string.
- Also see #pragma\SpecialChar ~
-CALLEE-SAVES.
-\layout List
-\labelwidthstring 00.00.0000
+\newline
-\series bold
---debug
-\bar under
-
-\series default
-\bar default
-When this option is used the compiler will generate debug information, that
- can be used with the SDCDB.
- The debug information is collected in a file with .cdb extension.
- For more information see documentation for SDCDB.
-\layout List
-\labelwidthstring 00.00.0000
+\newline
+4.
+ Documentation
+\layout Standard
-\series bold
-\emph on
---regextend
-\bar under
-
-\series default
-\bar default
- This option is obsolete and isn't supported anymore.
-\layout List
-\labelwidthstring 00.00.0000
+\begin_inset Tabular
+<lyxtabular version="3" rows="2" columns="3">
+<features>
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" rightline="true" width="0in">
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
-\emph on
---noregparms
-\series default
- This option is obsolete and isn't supported anymore.
-\layout List
-\labelwidthstring 00.00.0000
+Path
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
---peep-file
-\series default
-<filename> This option can be used to use additional rules to be used by
- the peep hole optimizer.
- See section Peep Hole optimizations for details on how to write these rules.
-\layout List
-\labelwidthstring 00.00.0000
+default
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
--S
-\size large
-\bar under
-
-\series default
-\size default
-\bar default
-Stop after the stage of compilation proper; do not assemble.
- The output is an assembler code file for the input file specified.
-\layout List
-\labelwidthstring 00.00.0000
+Win32 builds
+\end_inset
+</cell>
+</row>
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
--Wa_asmOption[,asmOption]
-\series default
-...
- Pass the asmOption to the assembler.
-\layout List
-\labelwidthstring 00.00.0000
+\emph on
+$DOCDIR
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\series bold
--Wl_linkOption[,linkOption]
-\series default
-...
- Pass the linkOption to the linker.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+/usr/local/share/sdcc/doc
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\series bold
---int-long-reent
-\series default
-\size large
-
-\size default
- Integer (16 bit) and long (32 bit) libraries have been compiled as reentrant.
- Note by default these libraries are compiled as non-reentrant.
- See section Installation for more details.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
-\series bold
---cyclomatic
-\bar under
-
-\series default
-\bar default
-This option will cause the compiler to generate an information message for
- each function in the source file.
- The message contains some
-\emph on
-important
-\emph default
- information about the function.
- The number of edges and nodes the compiler detected in the control flow
- graph of the function, and most importantly the
-\emph on
-cyclomatic complexity
-\emph default
- see section on Cyclomatic Complexity for more details.
-\layout List
-\labelwidthstring 00.00.0000
+\backslash
+sdcc
+\backslash
+doc
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+\end_inset
-\series bold
---float-reent
-\bar under
-
-\series default
-\bar default
- Floating point library is compiled as reentrant.See section Installation
- for more details.
-\layout List
-\labelwidthstring 00.00.0000
+\newline
-\series bold
---nooverlay
-\series default
- The compiler will not overlay parameters and local variables of any function,
- see section Parameters and local variables for more details.
-\layout List
-\labelwidthstring 00.00.0000
+\newline
+The install paths can still be changed during `make install` with e.g.:
+\layout LyX-Code
+make install prefix=$(HOME)/local/sdcc
+\layout Standard
-\series bold
---main-return
-\series default
- This option can be used when the code generated is called by a monitor
- program.
- The compiler will generate a 'ret' upon return from the 'main' function.
- The default option is to lock up i.e.
- generate a 'ljmp '.
-\layout List
-\labelwidthstring 00.00.0000
+Of course this doesn't change the search paths compiled into the binaries.
+\layout Subsection
+Search Paths
+\begin_inset LatexCommand \index{Search Paths}
-\series bold
---no-peep
-\series default
- Disable peep-hole optimization.
-\layout List
-\labelwidthstring 00.00.0000
+\end_inset
-\series bold
---peep-asm
-\series default
- Pass the inline assembler code through the peep hole optimizer.
- This can cause unexpected changes to inline assembler code, please go through
- the peephole optimizer rules defined in the source file tree '<target>/peeph.def
-' before using this option.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+Some search paths or parts of them are determined by configure variables
+ (in
+\emph on
+italics
+\emph default
+, see section above).
+ Further search paths are determined by environment variables during runtime.
+
+\newline
+The paths searched when running the compiler are as follows (the first catch
+ wins):
+\newline
-\series bold
---iram-size
-\series default
-<Value> Causes the linker to check if the interal ram usage is within limits
- of the given value.
-\layout List
-\labelwidthstring 00.00.0000
+\newline
+1.
+ Binary files (preprocessor, assembler and linker)
+\newline
+
+\begin_inset Tabular
+<lyxtabular version="3" rows="4" columns="3">
+<features>
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" width="0in">
+<column alignment="left" valignment="top" leftline="true" rightline="true" width="0in">
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
---nostdincl
-\series default
- This will prevent the compiler from passing on the default include path
- to the preprocessor.
-\layout List
-\labelwidthstring 00.00.0000
+Search path
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
---nostdlib
-\series default
- This will prevent the compiler from passing on the default library path
- to the linker.
-\layout List
-\labelwidthstring 00.00.0000
+default
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
---verbose
-\series default
- Shows the various actions the compiler is performing.
-\layout List
-\labelwidthstring 00.00.0000
+Win32 builds
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
-\series bold
--V
-\series default
- Shows the actual commands the compiler is executing.
-\layout Subsubsection
+$SDCC_HOME/
+\emph on
+$PPREFIX2BIN_DIR
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-Intermediate Dump Options
\layout Standard
-The following options are provided for the purpose of retargetting and debugging
- the compiler.
- These provided a means to dump the intermediate code (iCode) generated
- by the compiler in human readable form at various stages of the compilation
- process.
-
-\layout List
-\labelwidthstring 00.00.0000
-
+$SDCC_HOME/bin
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\series bold
---dumpraw
-\series default
- This option will cause the compiler to dump the intermediate code into
- a file of named
-\emph on
-<source filename>.dumpraw
-\emph default
- just after the intermediate code has been generated for a function, i.e.
- before any optimizations are done.
- The basic blocks at this stage ordered in the depth first number, so they
- may not be in sequence of execution.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+$SDCC_HOME
+\backslash
+bin
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\series bold
---dumpgcse
-\series default
- Will create a dump of iCode's, after global subexpression elimination,
- into a file named
-\emph on
-<source filename>.dumpgcse.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+Path of argv[0] (if available)
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\series bold
---dumpdeadcode
-\series default
- Will create a dump of iCode's, after deadcode elimination, into a file
- named
-\emph on
-<source filename>.dumpdeadcode.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+Path of argv[0]
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\series bold
---dumploop
-\series default
-\size large
-
-\size default
-Will create a dump of iCode's, after loop optimizations, into a file named
-
-\emph on
-<source filename>.dumploop.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+Path of argv[0]
+\end_inset
+</cell>
+</row>
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\series bold
---dumprange
-\series default
-\size large
-
-\size default
-Will create a dump of iCode's, after live range analysis, into a file named
-
-\emph on
-<source filename>.dumprange.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+$PATH
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\series bold
---dumlrange
-\series default
- Will dump the life ranges for all symbols.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+$PATH
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\series bold
---dumpregassign
-\bar under
-
-\series default
-\bar default
-Will create a dump of iCode's, after register assignment, into a file named
-
-\emph on
-<source filename>.dumprassgn.
-\layout List
-\labelwidthstring 00.00.0000
+\layout Standard
+$PATH
+\end_inset
+</cell>
+</row>
+</lyxtabular>
-\series bold
---dumplrange
-\series default
- Will create a dump of the live ranges of iTemp's
-\layout List
-\labelwidthstring 00.00.0000
+\end_inset
+
+\newline
-\series bold
---dumpall
-\size large
-\bar under
+\newline
+2.
+ Include files
+\newline
-\series default
-\size default
-\bar default
-Will cause all the above mentioned dumps to be created.
-\layout Subsection
+\begin_inset Tabular
+<lyxtabular version="3" rows="6" columns="3">
+<features>
+<column alignment="block" valignment="top" leftline="true" width="1.5in">
+<column alignment="block" valignment="top" leftline="true" width="1.5in">
+<column alignment="left" valignment="top" leftline="true" rightline="true" width="0in">
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-MCS51/DS390 Storage Class Language Extensions
\layout Standard
-In addition to the ANSI storage classes SDCC allows the following MCS51
- specific storage classes.
-\layout Subsubsection
+Search path
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-xdata
\layout Standard
-Variables declared with this storage class will be placed in the extern
- RAM.
- This is the
-\series bold
default
-\series default
- storage class for Large Memory model, e.g.:
-\newline
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\newline
+\layout Standard
-\family typewriter
-xdata unsigned char xduc;
-\layout Subsubsection
+Win32 builds
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-data
\layout Standard
-This is the
-\series bold
-default
-\series default
- storage class for Small Memory model.
- Variables declared with this storage class will be allocated in the internal
- RAM, e.g.:
-\newline
+---I dir
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\newline
+\layout Standard
-\family typewriter
-data int iramdata;
-\layout Subsubsection
+---I dir
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-idata
\layout Standard
-Variables declared with this storage class will be allocated into the indirectly
- addressable portion of the internal ram of a 8051, e.g.:
-\newline
+---I dir
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\newline
+\layout Standard
-\family typewriter
-idata int idi;
-\layout Subsubsection
+$SDCC_INCLUDE
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-bit
\layout Standard
-This is a data-type and a storage class specifier.
- When a variable is declared as a bit, it is allocated into the bit addressable
- memory of 8051, e.g.:
-\newline
+$SDCC_INCLUDE
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\newline
+\layout Standard
-\family typewriter
-bit iFlag;
-\layout Subsubsection
+$SDCC_INCLUDE
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-sfr / sbit
\layout Standard
-Like the bit keyword,
-\emph on
-sfr / sbit
-\emph default
-signifies both a data-type and storage class, they are used to describe
- the special function registers and special bit variables of a 8051, eg:
-\newline
-
+$SDCC_HOME/
\newline
-\family typewriter
-sfr at 0x80 P0; /* special function register P0 at location 0x80 */
+\emph on
+$PREFIX2DATA_DIR/
\newline
-sbit at 0xd7 CY; /* CY (Carry Flag) */
-\layout Subsection
+$INCLUDE_DIR_SUFFIX
+\end_inset
+</cell>
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-Pointers
\layout Standard
-SDCC allows (via language extensions) pointers to explicitly point to any
- of the memory spaces of the 8051.
- In addition to the explicit pointers, the compiler also allows a
-\emph on
-_generic
-\emph default
- class of pointers which can be used to point to any of the memory spaces.
-\newline
-
+$SDCC_ HOME/
\newline
-Pointer declaration examples:
+share/sdcc/
\newline
+include
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\size small
+\layout Standard
-\newline
+$SDCC_HOME
+\backslash
+include
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\family typewriter
-\size default
-/* pointer physically in xternal ram pointing to object in internal ram
- */
-\newline
-data unsigned char * xdata p;
-\newline
+\layout Standard
-\newline
-/* pointer physically in code rom pointing to data in xdata space */
-\newline
-xdata unsigned char * code p;
+path(argv[0])/
\newline
-\newline
-/* pointer physically in code space pointing to data in code space */
-\newline
-code unsigned char * code p;
+\emph on
+$BIN2DATADIR/
+\emph default
+
\newline
+\emph on
+$INCLUDE_DIR_SUFFIX
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+path(argv[0])/
\newline
-/* the folowing is a generic pointer physically located in xdata space */
+../sdcc/include
\newline
-char * xdata p;
-\family default
-\size small
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
-\newline
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\newline
+\layout Standard
-\size default
-Well you get the idea.
-
-\newline
+path(argv[0])
+\backslash
+..
+\backslash
+include
+\end_inset
+</cell>
+</row>
+<row topline="true" bottomline="true">
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
-\newline
\emph on
-For compatibility with the previous version of the compiler, the following
- syntax for pointer declaration is still supported but will disappear int
- the near future.
-
+$DATADIR/
+\emph default
+
\newline
+\emph on
+$INCLUDE_DIR_SUFFIX
+\end_inset
+</cell>
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+/usr/local/share/sdcc/
\newline
+include
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\family typewriter
-unsigned char _xdata *ucxdp; /* pointer to data in external ram */
+\layout Standard
+
+(not on Win32)
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
\newline
-unsigned char _data \SpecialChar ~
-*ucdp ; /* pointer to data in internal ram */
+
\newline
-unsigned char _code \SpecialChar ~
-*uccp ; /* pointer to data in R/O code space */
+ The option ---nostdinc disables the last two search paths.
\newline
-unsigned char _idata *uccp; \SpecialChar ~
-/* pointer to upper 128 bytes of ram */
-\family default
-\size small
-\emph default
\newline
-
+3.
+ Library files
\newline
+With the exception of
+\begin_inset Quotes sld
+\end_inset
-\size default
-All unqualified pointers are treated as 3-byte (4-byte for the ds390)
-\emph on
-generic
-\emph default
- pointers.
- These type of pointers can also to be explicitly declared.
-\newline
+---L dir
+\begin_inset Quotes srd
+\end_inset
+ the
+\shape italic
+model
+\shape default
+ is auto-appended by the compiler (e.g.
+ small, large, z80, ds390 etc.).
+
\newline
-\family typewriter
-unsigned char _generic *ucgp;
-\family default
-\size small
+\begin_inset Tabular
+<lyxtabular version="3" rows="6" columns="3">
+<features>
+<column alignment="block" valignment="top" leftline="true" width="1.7in">
+<column alignment="left" valignment="top" leftline="true" width="1.2in">
+<column alignment="block" valignment="top" leftline="true" rightline="true" width="1.2in">
+<row topline="true" bottomline="true">
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\newline
+\layout Standard
-\newline
+Search path
+\end_inset
+</cell>
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\size default
-The highest order byte of the
-\emph on
-generic
-\emph default
- pointers contains the data space information.
- Assembler support routines are called whenever data is stored or retrieved
- using
-\emph on
-generic
-\emph default
- pointers.
- These are useful for developing reusable library routines.
- Explicitly specifying the pointer type will generate the most efficient
- code.
- Pointers declared using a mixture of OLD and NEW style could have unpredictable
- results.
-\layout Subsection
+\layout Standard
+
+default
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-Parameters & Local Variables
\layout Standard
-Automatic (local) variables and parameters to functions can either be placed
- on the stack or in data-space.
- The default action of the compiler is to place these variables in the internal
- RAM (for small model) or external RAM (for Large model).
- This in fact makes them
-\emph on
-static
-\emph default
- so by default functions are non-reentrant.
+Win32 builds
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
\layout Standard
-They can be placed on the stack either by using the
-\emph on
- --stack-auto
-\emph default
- compiler option or by using the
-\emph on
-reentrant
-\emph default
- keyword in the function declaration, e.g.:
-\newline
+---L dir
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-\size small
+\layout Standard
-\newline
+---L dir
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\family typewriter
-\size default
-unsigned char foo(char i) reentrant
-\newline
-{
-\newline
-...
-
-\newline
-}
-\newline
+\layout Standard
-\family default
+---L dir
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
+
+$SDCC_LIB/
\newline
-Since stack space on 8051 is limited, the
-\emph on
-reentrant
-\emph default
-keyword or the
-\emph on
- --stack-auto
-\emph default
- option should be used sparingly.
- Note that the reentrant keyword just means that the parameters & local
- variables will be allocated to the stack, it
+
\emph on
-does not
-\emph default
- mean that the function is register bank independent.
-\newline
+<model>
+\end_inset
+</cell>
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+\layout Standard
+
+$SDCC_LIB/
\newline
-Local variables can be assigned storage classes and absolute addresses,
- e.g.:
+
+\emph on
+<model>
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+$SDCC_LIB
+\backslash
+
\newline
+\emph on
+<model>
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+$SDCC_HOME/
\newline
-\family typewriter
-unsigned char foo() {
+\emph on
+$PREFIX2DATA_DIR/
+\newline
+$LIB_DIR_SUFFIX/<model>
+\end_inset
+</cell>
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+$SDCC_HOME/
+\newline
+share/sdcc/
+\newline
+lib/
+\emph on
+<model>
+\end_inset
+</cell>
+<cell alignment="left" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+$SDCC_HOME
+\backslash
+lib
+\backslash
+
+\emph on
+
+\newline
+<model>
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+path(argv[0])/
+\newline
+
+\emph on
+$BIN2DATADIR/
+\emph default
+
+\newline
+
+\emph on
+$LIB_DIR_SUFFIX/<model>
+\end_inset
+</cell>
+<cell alignment="left" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+path(argv[0])/
+\newline
+../sdcc/lib/
+\emph on
+<model>
\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-xdata unsigned char i;
-\newline
-\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-bit bvar;
-\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-data at 0x31 unsiged char j;
-\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-...
-
-\newline
-}
-\newline
-
-\newline
-
-\family default
-In the above example the variable
-\emph on
-i
-\emph default
- will be allocated in the external ram,
-\emph on
-bvar
-\emph default
- in bit addressable space and
-\emph on
- j
-\emph default
- in internal ram.
- When compiled with
-\emph on
---stack-auto
-\emph default
- or when a function is declared as
-\emph on
-reentrant
-\emph default
- this can only be done for static variables.
-\layout Standard
-
-Parameters however are not allowed any storage class, (storage classes for
- parameters will be ignored), their allocation is governed by the memory
- model in use, and the reentrancy options.
-\layout Subsection
-
-Overlaying
-\layout Standard
-
-For non-reentrant functions SDCC will try to reduce internal ram space usage
- by overlaying parameters and local variables of a function (if possible).
- Parameters and local variables of a function will be allocated to an overlayabl
-e segment if the function has
-\emph on
-no other function calls and the function is non-reentrant and the memory
- model is small.
-
-\emph default
- If an explicit storage class is specified for a local variable, it will
- NOT be overlayed.
-\layout Standard
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
-Note that the compiler (not the linkage editor) makes the decision for overlayin
-g the data items.
- Functions that are called from an interrupt service routine should be preceded
- by a #pragma\SpecialChar ~
-NOOVERLAY if they are not reentrant.
-\layout Standard
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-Also note that the compiler does not do any processing of inline assembler
- code, so the compiler might incorrectly assign local variables and parameters
- of a function into the overlay segment if the inline assembler code calls
- other c-functions that might use the overlay.
- In that case the #pragma\SpecialChar ~
-NOOVERLAY should be used.
\layout Standard
-Parameters and Local variables of functions that contain 16 or 32 bit multiplica
-tion or division will NOT be overlayed since these are implemented using
- external functions, e.g.:
-\newline
+path(argv[0])
+\backslash
\newline
+..
+\backslash
+lib
+\backslash
-\family typewriter
-#pragma SAVE
-\newline
-#pragma NOOVERLAY
-\newline
-void set_error(unsigned char errcd)
-\newline
-{
+\emph on
+<model>
\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-P3 = errcd;
-\newline
-}
-\newline
-#pragma RESTORE
-\newline
-
-\newline
-void some_isr () interrupt 2 using 1
-\newline
-{
-\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-...
-\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-set_error(10);
-\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-...
-
-\newline
-}
-\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+
+\end_inset
+</cell>
+</row>
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
-\newline
-\family default
-In the above example the parameter
-\emph on
-errcd
-\emph default
- for the function
\emph on
-set_error
-\emph default
- would be assigned to the overlayable segment if the #pragma\SpecialChar ~
-NOOVERLAY was
- not present, this could cause unpredictable runtime behavior when called
- from an ISR.
- The #pragma\SpecialChar ~
-NOOVERLAY ensures that the parameters and local variables for
- the function are NOT overlayed.
-\layout Subsection
+$DATADIR/
+\newline
+$LIB_DIR_SUFFIX/<model>
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
-Interrupt Service Routines
\layout Standard
-SDCC allows interrupt service routines to be coded in C, with some extended
- keywords.
+/usr/local/share/sdcc/
\newline
+lib/
+\emph on
+<model>
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
-\newline
+\layout Standard
-\family typewriter
-void timer_isr (void) interrupt 2 using 1
-\newline
-{
-\newline
-..
-
-\newline
-}
-\newline
+(not on Win32)
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\layout Comment
+
+Don't delete any of the stray spaces in the table above without checking
+ the HTML output (last line)!
+\layout Standard
+
+\SpecialChar ~
\newline
+The option ---nostdlib disables the last two search paths.
+\layout Subsection
-\family default
-The number following the
-\emph on
-interrupt
-\emph default
- keyword is the interrupt number this routine will service.
- The compiler will insert a call to this routine in the interrupt vector
- table for the interrupt number specified.
- The
-\emph on
-using
-\emph default
- keyword is used to tell the compiler to use the specified register bank
- (8051 specific) when generating code for this function.
- Note that when some function is called from an interrupt service routine
- it should be preceded by a #pragma\SpecialChar ~
-NOOVERLAY if it is not reentrant.
- A special note here, int (16 bit) and long (32 bit) integer division, multiplic
-ation & modulus operations are implemented using external support routines
- developed in ANSI-C, if an interrupt service routine needs to do any of
- these operations then the support routines (as mentioned in a following
- section) will have to be recompiled using the
-\emph on
- --stack-auto
-\emph default
- option and the source file will need to be compiled using the
-\emph on
---int-long-ren
-\emph default
-t compiler option.
-\layout Standard
+Building SDCC
+\begin_inset LatexCommand \index{Building SDCC}
-If you have multiple source files in your project, interrupt service routines
- can be present in any of them, but a prototype of the isr MUST be present
- or included in the file that contains the function
-\emph on
-main
-\emph default
-.
-\layout Standard
+\end_inset
-Interrupt Numbers and the corresponding address & descriptions for the Standard
- 8051 are listed below.
- SDCC will automatically adjust the interrupt vector table to the maximum
- interrupt number specified.
-\newline
-\layout Standard
+\layout Subsubsection
+Building SDCC on Linux
+\layout Enumerate
-\begin_inset Tabular
-<lyxtabular version="2" rows="6" columns="3">
-<features rotate="false" islongtable="false" endhead="0" endfirsthead="0" endfoot="0" endlastfoot="0">
-<column alignment="center" valignment="top" leftline="true" rightline="false" width="" special="">
-<column alignment="center" valignment="top" leftline="true" rightline="false" width="" special="">
-<column alignment="center" valignment="top" leftline="true" rightline="true" width="" special="">
-<row topline="true" bottomline="true" newpage="false">
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
-\layout Standard
+\series medium
+Download the source package
+\series default
+ either from the SDCC CVS repository or from the
+\begin_inset LatexCommand \url[nightly snapshots]{http://sdcc.sourceforge.net/snap.php}
-Interrupt #
\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
-\layout Standard
-Description
-\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="true" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+\series medium
+, it will be named something like sdcc
+\series default
+.src
+\series medium
+.t
+\series default
+ar.
+\series medium
+gz.
+\layout Enumerate
-\layout Standard
-Vector Address
-\end_inset
-</cell>
-</row>
-<row topline="true" bottomline="false" newpage="false">
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+\series medium
+Bring up a command line terminal, such as xterm.
+\layout Enumerate
-\layout Standard
-0
-\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+\series medium
+Unpack the file using a command like:
+\family sans
+\series bold
+"tar -xzf sdcc.src.tar.gz
+\family default
+\series default
+"
+\series medium
+, this will create a sub-directory called sdcc with all of the sources.
+\layout Enumerate
-\layout Standard
+Change directory into the main SDCC directory, for example type:
+\family sans
+\series bold
+"cd sdcc
+\series default
+".
+\layout Enumerate
-External 0
-\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="true" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
-\layout Standard
+\series medium
+Type
+\family sans
+\series bold
+"./configure
+\family default
+\series default
+".
+ This configures the package for compilation on your system.
+\layout Enumerate
-0x0003
-\end_inset
-</cell>
-</row>
-<row topline="true" bottomline="false" newpage="false">
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
-\layout Standard
+\series medium
+Type
+\family sans
+\series bold
+"make
+\family default
+\series default
+"
+\series medium
+.
-1
-\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+\series default
+ All of the source packages will compile, this can take a while.
+\layout Enumerate
-\layout Standard
-Timer 0
-\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="true" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+\series medium
+Type
+\family sans
+\series bold
+"make install"
+\family default
+\series default
+ as root
+\series medium
+.
+
+\series default
+ This copies the binary executables, the include files, the libraries and
+ the documentation to the install directories.
+\layout Subsubsection
+Building SDCC on OSX 2.x
\layout Standard
-0x000B
-\end_inset
-</cell>
-</row>
-<row topline="true" bottomline="false" newpage="false">
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+Follow the instruction for Linux.
+\newline
-\layout Standard
+\newline
+On OSX 2.x it was reported, that the default gcc (version 3.1 20020420 (prerelease
+)) fails to compile SDCC.
+ Fortunately there's also gcc 2.9.x installed, which works fine.
+ This compiler can be selected by running 'configure' with:
+\layout LyX-Code
-2
-\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+./configure CC=gcc2 CXX=g++2
+\layout Subsubsection
+Crosscompiling SDCC on Linux for Windows
\layout Standard
-External 1
-\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="true" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+With the Mingw32 gcc crosscompiler it's easy to compile SDCC for Win32.
+ See section 'Configure Options'.
+\layout Subsubsection
+Building SDCC on Windows
\layout Standard
-0x0013
-\end_inset
-</cell>
-</row>
-<row topline="true" bottomline="false" newpage="false">
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+With the exception of Cygwin the SDCC binaries uCsim and sdcdb can't be
+ built on Windows.
+ They use Unix-sockets, which are not available on Win32.
+\layout Subsubsection
-\layout Standard
+Windows Install Using a Binary Package
+\layout Enumerate
-3
-\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+Download the binary package and unpack it using your favorite unpacking
+ tool (gunzip, WinZip, etc).
+ This should unpack to a group of sub-directories.
+ An example directory structure after unpacking the mingw32 package is:
+ c:
+\backslash
+sdcc
+\backslash
+bin for the executables, c:
+\backslash
+sdcc
+\backslash
+include and c:
+\backslash
+sdcc
+\backslash
+lib for the include and libraries.
+\layout Enumerate
+Adjust your environment variable PATH to include the location of the bin
+ directory or start sdcc using the full path.
+\layout Subsubsection
+
+Building SDCC using Cygwin and Mingw32
\layout Standard
-Timer 1
-\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="true" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+For building and installing a Cygwin executable follow the instructions
+ for Linux.
+\newline
-\layout Standard
+\newline
+On Cygwin a
+\begin_inset Quotes sld
+\end_inset
-0x001B
+native
+\begin_inset Quotes srd
\end_inset
-</cell>
-</row>
-<row topline="true" bottomline="true" newpage="false">
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
-\layout Standard
+ Win32-binary can be built, which will not need the Cygwin-DLL.
+ For the necessary 'configure' options see section 'configure options' or
+ the script 'sdcc/support/scripts/sdcc_cygwinmingw32'.
+\newline
-4
-\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="false" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
+\newline
+In order to install Cygwin on Windows download setup.exe from
+\begin_inset LatexCommand \url[www.cygwin.com]{http://www.cygwin.com/}
-\layout Standard
+\end_inset
-Serial
+.
+ Run it, set the
+\begin_inset Quotes sld
\end_inset
-</cell>
-<cell multicolumn="0" alignment="center" valignment="top" topline="true" bottomline="false" leftline="true" rightline="true" rotate="false" usebox="none" width="" special="">
-\begin_inset Text
-\layout Standard
+default text file type
+\begin_inset Quotes srd
+\end_inset
-0x0023
+ to
+\begin_inset Quotes sld
\end_inset
-</cell>
-</row>
-</lyxtabular>
+unix
+\begin_inset Quotes srd
\end_inset
+ and download/install at least the following packages.
+ Some packages are selected by default, others will be automatically selected
+ because of dependencies with the manually selected packages.
+ Never deselect these packages!
+\layout Itemize
-\newline
+flex
+\layout Itemize
-\newline
-If the interrupt service routine is defined without
-\emph on
-using
-\emph default
- a register bank or with register bank 0 (using 0), the compiler will save
- the registers used by itself on the stack upon entry and restore them at
- exit, however if such an interrupt service routine calls another function
- then the entire register bank will be saved on the stack.
- This scheme may be advantageous for small interrupt service routines which
- have low register usage.
-\layout Standard
+bison
+\layout Itemize
-If the interrupt service routine is defined to be using a specific register
- bank then only
-\emph on
-a, b & dptr
-\emph default
- are save and restored, if such an interrupt service routine calls another
- function (using another register bank) then the entire register bank of
- the called function will be saved on the stack.
- This scheme is recommended for larger interrupt service routines.
+gcc ; version 3.x is fine, no need to use the old 2.9x
+\layout Itemize
+
+binutils ; selected with gcc
+\layout Itemize
+
+make
+\layout Itemize
+
+rxvt ; a nice console, which makes life much easier under windoze (see below)
+\layout Itemize
+
+man ; not really needed for building SDCC, but you'll miss it sooner or
+ later
+\layout Itemize
+
+less ; not really needed for building SDCC, but you'll miss it sooner or
+ later
+\layout Itemize
+
+cvs ; only if you use CVS access
\layout Standard
-Calling other functions from an interrupt service routine is not recommended,
- avoid it if possible.
-\newline
+If you want to develop something you'll need:
+\layout Itemize
-\newline
-Also see the _naked modifier.
-\layout Subsection
+python ; for the regression tests
+\layout Itemize
-Critical Functions
+gdb ; the gnu debugger, together with the nice GUI
+\begin_inset Quotes sld
+\end_inset
+
+insight
+\begin_inset Quotes srd
+\end_inset
+
+
+\layout Itemize
+
+openssh ; to access the CF or commit changes
+\layout Itemize
+
+autoconf and autoconf-devel ; if you want to fight with 'configure', don't
+ use autoconf-stable!
\layout Standard
-A special keyword may be associated with a function declaring it as
-\emph on
-critical
-\emph default
-.
- SDCC will generate code to disable all interrupts upon entry to a critical
- function and enable them back before returning.
- Note that nesting critical functions may cause unpredictable results.
-\newline
+rxvt is a nice console with history.
+ Replace in your cygwin.bat the line
+\layout LyX-Code
-\size small
+bash --login -i
+\layout Standard
-\newline
+with (one line):
+\layout LyX-Code
-\family typewriter
-\size default
-int foo () critical
-\newline
-{
-\newline
-...
-
-\newline
-...
-
+rxvt -sl 1000 -fn "Lucida Console-12" -sr -cr red
+\layout LyX-Code
+
+ -bg black -fg white -geometry 100x65 -e bash --login
+\layout Standard
+
+Text selected with the mouse is automatically copied to the clipboard, pasting
+ works with shift-insert.
\newline
-}
+
\newline
+The other good tip is to make sure you have no //c/-style paths anywhere,
+ use /cygdrive/c/ instead.
+ Using // invokes a network lookup which is very slow.
+ If you think
+\begin_inset Quotes sld
+\end_inset
-\family default
+cygdrive
+\begin_inset Quotes srd
+\end_inset
-\newline
-The critical attribute maybe used with other attributes like
-\emph on
-reentrant.
-\layout Subsection
+ is too long, you can change it with e.g.
+\layout LyX-Code
-Naked Functions
+mount -s -u -c /mnt
\layout Standard
-A special keyword may be associated with a function declaring it as
-\emph on
-_naked.
+SDCC sources use the unix line ending LF.
+ Life is much easier, if you store the source tree on a drive, which is
+ mount in binary mode.
+ And use an editor which can handle LF-only line endings.
+ Make sure not to commit files with windows line endings.
+\layout Subsubsection
+
+Windows Install Using Microsoft Visual C++ 6.0/NET
+\layout Standard
+
+
+\series medium
+Download the source package
+\series default
+ either from the SDCC CVS repository or from the
+\begin_inset LatexCommand \url[nightly snapshots]{http://sdcc.sourceforge.net/snap.php}
+
+\end_inset
+
+
+\series medium
+, it will be named something like sdcc
+\series default
+.src
+\series medium
+.tgz.
+
+\series default
+ SDCC is distributed with all the projects, workspaces, and files you need
+ to build it using Visual C++ 6.0/NET.
+ The workspace name is 'sdcc.dsw'.
+ Please note that as it is now, all the executables are created in a folder
+ called sdcc
+\backslash
+bin_vc.
+ Once built you need to copy the executables from sdcc
+\backslash
+bin_vc to sdcc
+\backslash
+bin before runnng SDCC.
-\emph default
-The
-\emph on
-_naked
-\emph default
- function modifier attribute prevents the compiler from generating prologue
- and epilogue code for that function.
- This means that the user is entirely responsible for such things as saving
- any registers that may need to be preserved, selecting the proper register
- bank, generating the
-\emph on
-return
-\emph default
- instruction at the end, etc.
- Practically, this means that the contents of the function must be written
- in inline assembler.
- This is particularly useful for interrupt functions, which can have a large
- (and often unnecessary) prologue/epilogue.
- For example, compare the code generated by these two functions:
\newline
\newline
+In order to build SDCC with Visual C++ 6.0/NET you need win32 executables
+ of bison.exe, flex.exe, and gawk.exe.
+ One good place to get them is
+\begin_inset LatexCommand \url[here]{http://unxutils.sourceforge.net}
+
+\end_inset
+
-\family typewriter
-data unsigned char counter;
\newline
-void simpleInterrupt(void) interrupt 1
+
\newline
-{
+Download the file UnxUtils
+\begin_inset LatexCommand \index{UnxUtils}
+
+\end_inset
+
+.zip.
+ Now you have to install the utilities and setup Visual C++ so it can locate
+ the required programs.
+ Here there are two alternatives (choose one!):
+\layout Enumerate
+
+The easy way:
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-counter++;
+
\newline
-}
+a) Extract UnxUtils.zip to your C:
+\backslash
+ hard disk PRESERVING the original paths, otherwise bison won't work.
+ (If you are using WinZip make certain that 'Use folder names' is selected)
\newline
\newline
-void nakedInterrupt(void) interrupt 2 _naked
-\newline
-{
+b) In the Visual C++ IDE click Tools, Options, select the Directory tab,
+ in 'Show directories for:' select 'Executable files', and in the directories
+ window add a new path: 'C:
+\backslash
+user
+\backslash
+local
+\backslash
+wbin', click ok.
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-_asm
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-inc\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-_counter
+(As a side effect, you get a bunch of Unix utilities that could be useful,
+ such as diff and patch.)
+\layout Enumerate
+
+A more compact way:
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-reti\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-; MUST explicitly include ret in _naked function.
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-_endasm;
+This one avoids extracting a bunch of files you may not use, but requires
+ some extra work:
\newline
-}
-\family default
+\newline
+a) Create a directory were to put the tools needed, or use a directory already
+ present.
+ Say for example 'C:
+\backslash
+util'.
\newline
\newline
-For an 8051 target, the generated simpleInterrupt looks like:
+b) Extract 'bison.exe', 'bison.hairy', 'bison.simple', 'flex.exe', and gawk.exe
+ to such directory WITHOUT preserving the original paths.
+ (If you are using WinZip make certain that 'Use folder names' is not selected)
\newline
+\newline
+c) Rename bison.exe to '_bison.exe'.
\newline
-\family typewriter
-_simpleIterrupt:
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-push\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-acc
+d) Create a batch file 'bison.bat' in 'C:
+\backslash
+util
+\backslash
+' and add these lines:
\newline
\SpecialChar ~
\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-push\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-b
+set BISON_SIMPLE=C:
+\backslash
+util
+\backslash
+bison.simple
\newline
\SpecialChar ~
\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-push\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-dpl
+set BISON_HAIRY=C:
+\backslash
+util
+\backslash
+bison.hairy
\newline
\SpecialChar ~
\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-push\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-dph
+_bison %1 %2 %3 %4 %5 %6 %7 %8 %9
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-push\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-psw
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-mov\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-psw,#0x00
+Steps 'c' and 'd' are needed because bison requires by default that the
+ files 'bison.simple' and 'bison.hairy' reside in some weird Unix directory,
+ '/usr/local/share/' I think.
+ So it is necessary to tell bison where those files are located if they
+ are not in such directory.
+ That is the function of the environment variables BISON_SIMPLE and BISON_HAIRY.
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-inc\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-_counter
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-pop\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-psw
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-pop\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-dph
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-pop\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-dpl
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-pop\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-b
+e) In the Visual C++ IDE click Tools, Options, select the Directory tab,
+ in 'Show directories for:' select 'Executable files', and in the directories
+ window add a new path: 'c:
+\backslash
+util', click ok.
+ Note that you can use any other path instead of 'c:
+\backslash
+util', even the path where the Visual C++ tools are, probably: 'C:
+\backslash
+Program Files
+\backslash
+Microsoft Visual Studio
+\backslash
+Common
+\backslash
+Tools'.
+ So you don't have to execute step 'e' :)
+\layout Standard
+
+That is it.
+ Open 'sdcc.dsw' in Visual Studio, click 'build all', when it finishes copy
+ the executables from sdcc
+\backslash
+bin_vc to sdcc
+\backslash
+bin, and you can compile using sdcc.
+\layout Subsubsection
+
+Windows Install Using Borland
+\layout Enumerate
+
+From the sdcc directory, run the command "make -f Makefile.bcc".
+ This should regenerate all the .exe files in the bin directory except for
+ sdcdb.exe (which currently doesn't build under Borland C++).
+\layout Enumerate
+
+If you modify any source files and need to rebuild, be aware that the dependanci
+es may not be correctly calculated.
+ The safest option is to delete all .obj files and run the build again.
+ From a Cygwin BASH prompt, this can easily be done with the commmand:
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-pop\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-acc
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-reti
+
+\family sans
+\series bold
+find .
+
+\backslash
+( -name '*.obj' -o -name '*.lib' -o -name '*.rul'
+\backslash
+) -print -exec rm {}
+\backslash
+;
\family default
+\series default
\newline
\newline
-whereas nakedInterrupt looks like:
+or on Windows NT/2000/XP from the command prompt with the commmand:
\newline
-\newline
+\family sans
+\series bold
-\family typewriter
-_nakedInterrupt:
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-inc\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-_counter
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-reti\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-; MUST explicitly include ret(i) in _naked function.
+del /s *.obj *.lib *.rul
\family default
+\series default
+ from the sdcc directory.
+\layout Subsection
-\newline
+Building the Documentation
+\layout Standard
-\newline
-While there is nothing preventing you from writing C code inside a _naked
- function, there are many ways to shoot yourself in the foot doing this,
- and is is recommended that you stick to inline assembler.
+...
+ coming soon
\layout Subsection
-Functions using private banks
+Testing out the SDCC Compiler
\layout Standard
-The
-\emph on
-using
-\emph default
- attribute (which tells the compiler to use a register bank other than the
- default bank zero) should only be applied to
-\emph on
-interrupt
-\emph default
- functions (see note 1 below).
- This will in most circumstances make the generated ISR code more efficient
- since it will not have to save registers on the stack.
-\layout Standard
+The first thing you should do after installing your SDCC compiler is to
+ see if it runs.
+ Type
+\family sans
+\series bold
+"sdcc ---version"
+\begin_inset LatexCommand \index{version}
-The
-\emph on
-using
-\emph default
- attribute will have no effect on the generated code for a
-\emph on
-non-interrupt
-\emph default
- function (but may occasionally be useful anyway
-\begin_float footnote
-\layout Standard
+\end_inset
-possible exception: if a function is called ONLY from 'interrupt' functions
- using a particular bank, it can be declared with the same 'using' attribute
- as the calling 'interrupt' functions.
- For instance, if you have several ISRs using bank one, and all of them
- call memcpy(), it might make sense to create a specialized version of memcpy()
- 'using 1', since this would prevent the ISR from having to save bank zero
- to the stack on entry and switch to bank zero before calling the function
-\end_float
-).
+
+\family default
+\series default
+ at the prompt, and the program should run and tell you the version.
+ If it doesn't run, or gives a message about not finding sdcc program, then
+ you need to check over your installation.
+ Make sure that the sdcc bin directory is in your executable search path
+ defined by the PATH environment setting (see the Trouble-shooting section
+ for suggestions).
+ Make sure that the sdcc program is in the bin folder, if not perhaps something
+ did not install correctly.
\newline
-\emph on
-(pending: I don't think this has been done yet)
-\layout Standard
+\newline
-An
-\emph on
-interrupt
-\emph default
- function using a non-zero bank will assume that it can trash that register
- bank, and will not save it.
- Since high-priority interrupts can interrupt low-priority ones on the 8051
- and friends, this means that if a high-priority ISR
-\emph on
-using
-\emph default
- a particular bank occurs while processing a low-priority ISR
-\emph on
-using
-\emph default
- the same bank, terrible and bad things can happen.
- To prevent this, no single register bank should be
-\emph on
-used
-\emph default
- by both a high priority and a low priority ISR.
- This is probably most easily done by having all high priority ISRs use
- one bank and all low priority ISRs use another.
- If you have an ISR which can change priority at runtime, you're on your
- own: I suggest using the default bank zero and taking the small performance
- hit.
-\layout Standard
+\series medium
+SDCC
+\series default
+is commonly installed as described in section
+\begin_inset Quotes sld
+\end_inset
-It is most efficient if your ISR calls no other functions.
- If your ISR must call other functions, it is most efficient if those functions
- use the same bank as the ISR (see note 1 below); the next best is if the
- called functions use bank zero.
- It is very inefficient to call a function using a different, non-zero bank
- from an ISR.
-
-\layout Subsection
+Install and search paths
+\begin_inset Quotes srd
+\end_inset
-Absolute Addressing
-\layout Standard
-Data items can be assigned an absolute address with the
-\emph on
-at <address>
-\emph default
- keyword, in addition to a storage class, e.g.:
\newline
\newline
-\family typewriter
-xdata at 0x8000 unsigned char PORTA_8255 ;
+\series medium
+Make sure the compiler works on a very simple example.
+ Type in the following test.c program using your favorite
+\series default
+ascii
+\series medium
+editor:
+\series default
+
\newline
-\family default
+\family typewriter
\newline
-In the above example the PORTA_8255 will be allocated to the location 0x8000
- of the external ram.
- Note that this feature is provided to give the programmer access to
-\emph on
-memory mapped
-\emph default
- devices attached to the controller.
- The compiler does not actually reserve any space for variables declared
- in this way (they are implemented with an equate in the assembler).
- Thus it is left to the programmer to make sure there are no overlaps with
- other variables that are declared without the absolute address.
- The assembler listing file (.lst) and the linker output files (.rst) and
- (.map) are a good places to look for such overlaps.
+char test;
\newline
\newline
-Absolute address can be specified for variables in all storage classes,
- e.g.:
-\newline
-
+void main(void) {
\newline
-
-\family typewriter
-bit at 0x02 bvar;
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+test=0;
\newline
+}
+\family default
\newline
-\family default
-The above example will allocate the variable at offset 0x02 in the bit-addressab
-le space.
- There is no real advantage to assigning absolute addresses to variables
- in this manner, unless you want strict control over all the variables allocated.
-\layout Subsection
+\emph on
-Startup Code
-\layout Standard
+\newline
-The compiler inserts a call to the C routine
-\emph on
-_sdcc__external__startup()
-\series bold
+\series medium
\emph default
-
-\series default
-at the start of the CODE area.
- This routine is in the runtime library.
- By default this routine returns 0, if this routine returns a non-zero value,
- the static & global variable initialization will be skipped and the function
- main will be invoked Other wise static & global variables will be initialized
- before the function main is invoked.
- You could add a
-\emph on
-_sdcc__external__startup()
-\emph default
- routine to your program to override the default if you need to setup hardware
- or perform some other critical operation prior to static & global variable
- initialization.
-\layout Subsection
+Compile this using the following command:
+\family sans
+\series bold
+"sdcc -c test.c".
-Inline Assembler Code
-\layout Standard
+\family default
+\series default
+
+\series medium
+If all goes well, the compiler will generate a test.asm and test.rel file.
+ Congratulations, you've just compiled your first program with SDCC.
+ We used the -c option to tell SDCC not to link the generated code, just
+ to keep things simple for this step.
+\series default
-SDCC allows the use of in-line assembler with a few restriction as regards
- labels.
- All labels defined within inline assembler code
-\emph on
-has to be
-\emph default
- of the form
-\emph on
-nnnnn$
-\emph default
- where nnnn is a number less than 100 (which implies a limit of utmost 100
- inline assembler labels
-\emph on
-per function
-\emph default
-\noun on
-)
-\noun default
-.
- It is strongly recommended that each assembly instruction (including labels)
- be placed in a separate line (as the example shows).
- When the
-\emph on
---peep-asm
-\emph default
- command line option is used, the inline assembler code will be passed through
- the peephole optimizer.
- This might cause some unexpected changes in the inline assembler code.
- Please go throught the peephole optimizer rules defined in file
-\emph on
-SDCCpeeph.def
-\emph default
- carefully before using this option.
\newline
\newline
-\family typewriter
-_asm
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-mov\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-b,#10
-\newline
-00001$:
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-djnz\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-b,00001$
-\newline
-_endasm ;
+\series medium
+The next step is to try it with the linker.
+ Type in
+\family sans
+\series bold
+"sdcc test.c
\family default
-\size small
+\series default
+"
+\series medium
+.
+ If all goes well the compiler will link with the libraries and produce
+ a test.ihx output file.
+ If this step fails
+\series default
+
+\series medium
+(no test.ihx, and the linker generates warnings), then the problem is most
+ likely that sdcc cannot find the
+\series default
+/
+\series medium
+usr/local/share/sdcc/lib directory
+\series default
+
+\series medium
+(see the Install trouble-shooting section for suggestions).
+\series default
\newline
\newline
-\size default
-The inline assembler code can contain any valid code understood by the assembler
-, this includes any assembler directives and comment lines.
- The compiler does not do any validation of the code within the
-\family typewriter
-_asm ...
- _endasm;
-\family default
- keyword pair.
-
-\newline
+\series medium
+The final test is to ensure sdcc can use the
+\series default
+standard
+\series medium
+ header files and libraries.
+ Edit test.c and change it to the following:
+\series default
\newline
-Inline assembler code cannot reference any C-Labels, however it can reference
- labels defined by the inline assembler, e.g.:
-\newline
\newline
\family typewriter
-foo() {
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-/* some c code */
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-_asm
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-; some assembler code
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-ljmp $0003
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-_endasm;
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-/* some more c code */
+#include <string.h>
\newline
-clabel:\SpecialChar ~
-\SpecialChar ~
-/* inline assembler cannot reference this label */
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-_asm
+char str1[10];
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-$0003: ;label (can be reference by inline assembler only)
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-_endasm ;
+void main(void) {
\newline
\SpecialChar ~
\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-/* some more c code */
+strcpy(str1, "testing");
\newline
}
\newline
\newline
\family default
-In other words inline assembly code can access labels defined in inline
- assembly within the scope of the funtion.
+\series medium
+Compile this by typing
+\family sans
+\series bold
+"sdcc test.c"
+\family default
+\series medium
+.
+ This should generate a test.ihx output file, and it should give no warnings
+ such as not finding the string.h file.
+ If it cannot find the string.h file, then the problem is that sdcc cannot
+ find the /usr/local/share/sdcc/include directory
+\series default
-\layout Standard
-
-The same goes the other way, ie.
- labels defines in inline assembly CANNOT be accessed by C statements.
+\series medium
+(see the Install trouble-shooting section for suggestions).
\layout Subsection
-int(16 bit) and long (32 bit) Support
+Install Trouble-shooting
+\begin_inset LatexCommand \index{Install Trouble-shooting}
+
+\end_inset
+
+
+\layout Subsubsection
+
+SDCC does not build correctly.
\layout Standard
-For signed & unsigned int (16 bit) and long (32 bit) variables, division,
- multiplication and modulus operations are implemented by support routines.
- These support routines are all developed in ANSI-C to facilitate porting
- to other MCUs, although some model specific assembler optimations are used.
- The following files contain the described routine, all of them can be found
- in <installdir>/share/sdcc/lib.
+A thing to try is starting from scratch by unpacking the .tgz source package
+ again in an empty directory.
+ Configure it like:
\newline
\newline
-\emph on
-<pending: tabularise this>
-\emph default
+\family sans
+\series bold
+./configure 2>&1 | tee configure.log
+\family default
+\series default
\newline
\newline
-_mulsint.c - signed 16 bit multiplication (calls _muluint)
+and build it like:
\newline
-_muluint.c - unsigned 16 bit multiplication
+
\newline
-_divsint.c - signed 16 bit division (calls _divuint)
+
+\family sans
+\series bold
+make 2>&1 | tee make.log
+\family default
+\series default
+
\newline
-_divuint.c - unsigned 16 bit division
-\newline
-_modsint.c - signed 16 bit modulus (call _moduint)
-\newline
-_moduint.c - unsigned 16 bit modulus
-\newline
-_mulslong.c - signed 32 bit multiplication (calls _mululong)
-\newline
-_mululong.c - unsigned32 bit multiplication
-\newline
-_divslong.c - signed 32 division (calls _divulong)
-\newline
-_divulong.c - unsigned 32 division
-\newline
-_modslong.c - signed 32 bit modulus (calls _modulong)
-\newline
-_modulong.c - unsigned 32 bit modulus
-\size footnotesize
\newline
+If anything goes wrong, you can review the log files to locate the problem.
+ Or a relevant part of this can be attached to an email that could be helpful
+ when requesting help from the mailing list.
+\layout Subsubsection
-\newline
+What the
+\begin_inset Quotes sld
+\end_inset
-\size default
-Since they are compiled as
-\emph on
-non-reentrant
-\emph default
-, interrupt service routines should not do any of the above operations.
- If this is unavoidable then the above routines will need to be compiled
- with the
-\emph on
---stack-auto
-\emph default
- option, after which the source program will have to be compiled with
-\emph on
---int-long-rent
-\emph default
- option.
-\layout Subsection
+./configure
+\begin_inset Quotes srd
+\end_inset
-Floating Point Support
+ does
\layout Standard
-SDCC supports IEEE (single precision 4bytes) floating point numbers.The floating
- point support routines are derived from gcc's floatlib.c and consists of
- the following routines:
-\newline
+The
+\begin_inset Quotes sld
+\end_inset
-\newline
+./configure
+\begin_inset Quotes srd
+\end_inset
-\emph on
-<pending: tabularise this>
-\emph default
+ command is a script that analyzes your system and performs some configuration
+ to ensure the source package compiles on your system.
+ It will take a few minutes to run, and will compile a few tests to determine
+ what compiler features are installed.
+\layout Subsubsection
-\newline
+What the
+\begin_inset Quotes sld
+\end_inset
-\newline
-_fsadd.c - add floating point numbers
-\newline
-_fssub.c - subtract floating point numbers
-\newline
-_fsdiv.c - divide floating point numbers
-\newline
-_fsmul.c - multiply floating point numbers
-\newline
-_fs2uchar.c - convert floating point to unsigned char
-\newline
-_fs2char.c - convert floating point to signed char
-\newline
-_fs2uint.c - convert floating point to unsigned int
-\newline
-_fs2int.c - convert floating point to signed int
-\newline
-_fs2ulong.c - convert floating point to unsigned long
-\newline
-_fs2long.c - convert floating point to signed long
-\newline
-_uchar2fs.c - convert unsigned char to floating point
-\newline
-_char2fs.c - convert char to floating point number
-\newline
-_uint2fs.c - convert unsigned int to floating point
-\newline
-_int2fs.c - convert int to floating point numbers
-\newline
-_ulong2fs.c - convert unsigned long to floating point number
-\newline
-_long2fs.c - convert long to floating point number
-\size footnotesize
+make
+\begin_inset Quotes srd
+\end_inset
-\newline
+ does.
+\layout Standard
-\newline
+This runs the GNU make tool, which automatically compiles all the source
+ packages into the final installed binary executables.
+\layout Subsubsection
-\size default
-Note if all these routines are used simultaneously the data space might
- overflow.
- For serious floating point usage it is strongly recommended that the large
- model be used.
-\layout Subsection
+What the
+\begin_inset Quotes sld
+\end_inset
-MCS51 Memory Models
-\layout Standard
+make install
+\begin_inset Quotes erd
+\end_inset
-SDCC allows two memory models for MCS51 code, small and large.
- Modules compiled with different memory models should
-\emph on
-never
-\emph default
- be combined together or the results would be unpredictable.
- The library routines supplied with the compiler are compiled as both small
- and large.
- The compiled library modules are contained in seperate directories as small
- and large so that you can link to either set.
-
+ command does.
\layout Standard
-When the large model is used all variables declared without a storage class
- will be allocated into the external ram, this includes all parameters and
- local variables (for non-reentrant functions).
- When the small model is used variables without storage class are allocated
- in the internal ram.
-\layout Standard
+This will install the compiler, other executables libraries and include
+ files in to the appropriate directories.
+ See section
+\begin_inset Quotes sld
+\end_inset
-Judicious usage of the processor specific storage classes and the 'reentrant'
- function type will yield much more efficient code, than using the large
- model.
- Several optimizations are disabled when the program is compiled using the
- large model, it is therefore strongly recommdended that the small model
- be used unless absolutely required.
+Install and Search PATHS
+\begin_inset Quotes srd
+\end_inset
+
+.
+\newline
+On most systems you will need super-user privilages to do this.
\layout Subsection
-DS390 Memory Models
+Components of SDCC
\layout Standard
-The only model supported is Flat 24.
- This generates code for the 24 bit contiguous addressing mode of the Dallas
- DS80C390 part.
- In this mode, up to four meg of external RAM or code space can be directly
- addressed.
- See the data sheets at www.dalsemi.com for further information on this part.
-\newline
-
-\newline
-In older versions of the compiler, this option was used with the MCS51 code
- generator (
-\emph on
--mmcs51
-\emph default
-).
- Now, however, the '390 has it's own code generator, selected by the
-\emph on
--mds390
-\emph default
- switch.
-
+SDCC is not just a compiler, but a collection of tools by various developers.
+ These include linkers, assemblers, simulators and other components.
+ Here is a summary of some of the components.
+ Note that the included simulator and assembler have separate documentation
+ which you can find in the source package in their respective directories.
+ As SDCC grows to include support for other processors, other packages from
+ various developers are included and may have their own sets of documentation.
\newline
\newline
-Note that the compiler does not generate any code to place the processor
- into 24 bitmode (although
-\emph on
-tinibios
-\emph default
- in the ds390 libraries will do that for you).
- If you don't use
-\emph on
-tinibios
-\emph default
-, the boot loader or similar code must ensure that the processor is in 24
- bit contiguous addressing mode before calling the SDCC startup code.
-\newline
-
+You might want to look at the files which are installed in <installdir>.
+ At the time of this writing, we find the following programs for gcc-builds:
\newline
-Like the
-\emph on
---model-large
-\emph default
- option, variables will by default be placed into the XDATA segment.
\newline
+In <installdir>/bin:
+\layout Itemize
-\newline
-Segments may be placed anywhere in the 4 meg address space using the usual
- --*-loc options.
- Note that if any segments are located above 64K, the -r flag must be passed
- to the linker to generate the proper segment relocations, and the Intel
- HEX output format must be used.
- The -r flag can be passed to the linker by using the option
-\emph on
--Wl-r
-\emph default
- on the sdcc command line.
- However, currently the linker can not handle code segments > 64k.
-\layout Subsection
-
-Defines Created by the Compiler
-\layout Standard
+sdcc - The compiler.
+\layout Itemize
-The compiler creates the following #defines.
+sdcpp - The C preprocessor.
\layout Itemize
-SDCC - this Symbol is always defined.
+asx8051 - The assembler for 8051 type processors.
\layout Itemize
-SDCC_mcs51 or SDCC_ds390 or SDCC_z80, etc - depending on the model used
- (e.g.: -mds390)
+as-z80
+\series bold
+,
+\series default
+as-gbz80 - The Z80 and GameBoy Z80 assemblers.
\layout Itemize
-__mcs51 or __ds390 or __z80, etc - depending on the model used (e.g.
- -mz80)
+aslink -The linker for 8051 type processors.
\layout Itemize
-SDCC_STACK_AUTO - this symbol is defined when
-\emph on
---stack-auto
-\emph default
- option is used.
+link-z80
+\series bold
+,
+\series default
+link-gbz80 - The Z80 and GameBoy Z80 linkers.
\layout Itemize
-SDCC_MODEL_SMALL - when
-\emph on
---model-small
-\emph default
- is used.
+s51 - The ucSim 8051 simulator.
\layout Itemize
-SDCC_MODEL_LARGE - when
-\emph on
---model-large
-\emph default
- is used.
+sdcdb - The source debugger.
\layout Itemize
-SDCC_USE_XSTACK - when
-\emph on
---xstack
-\emph default
- option is used.
+packihx - A tool to pack (compress) Intel hex files.
+\layout Standard
+
+In <installdir>/share/sdcc/include
\layout Itemize
-SDCC_STACK_TENBIT - when
-\emph on
--mds390
-\emph default
- is used
+the include files
+\layout Standard
+
+In <installdir>/share/sdcc/lib
\layout Itemize
-SDCC_MODEL_FLAT24 - when
-\emph on
--mds390
-\emph default
- is used
-\layout Section
+the subdirs src and small, large, z80, gbz80 and ds390 with the precompiled
+ relocatables.
+\layout Standard
-SDCC Technical Data
-\layout Subsection
+In <installdir>/share/sdcc/doc
+\layout Itemize
-Optimizations
+the documentation
\layout Standard
-SDCC performs a host of standard optimizations in addition to some MCU specific
- optimizations.
-
+As development for other processors proceeds, this list will expand to include
+ executables to support processors like AVR, PIC, etc.
\layout Subsubsection
-Sub-expression Elimination
+sdcc - The Compiler
\layout Standard
-The compiler does local and global common subexpression elimination, e.g.:
-
-\newline
+This is the actual compiler, it in turn uses the c-preprocessor and invokes
+ the assembler and linkage editor.
+\layout Subsubsection
-\newline
+sdcpp - The C-Preprocessor
+\layout Standard
-\family typewriter
-i = x + y + 1;
-\newline
-j = x + y;
-\family default
+The preprocessor is a modified version of the GNU preprocessor.
+ The C preprocessor is used to pull in #include sources, process #ifdef
+ statements, #defines and so on.
+\layout Subsubsection
-\newline
+asx8051, as-z80, as-gbz80, aslink, link-z80, link-gbz80 - The Assemblers
+ and Linkage Editors
+\layout Standard
-\newline
-will be translated to
-\newline
+This is retargettable assembler & linkage editor, it was developed by Alan
+ Baldwin.
+ John Hartman created the version for 8051, and I (Sandeep) have made some
+ enhancements and bug fixes for it to work properly with the SDCC.
+\layout Subsubsection
-\newline
+s51 - The Simulator
+\begin_inset LatexCommand \index{s51 - The Simulator}
-\family typewriter
-iTemp = x + y
-\newline
-i = iTemp + 1
-\newline
-j = iTemp
-\newline
+\end_inset
-\family default
-\newline
-Some subexpressions are not as obvious as the above example, e.g.:
-\newline
+\layout Standard
-\newline
+S51 is a freeware, opensource simulator developed by Daniel Drotos (
+\begin_inset LatexCommand \url{mailto:drdani@mazsola.iit.uni-miskolc.hu}
-\family typewriter
-a->b[i].c = 10;
-\newline
-a->b[i].d = 11;
-\family default
+\end_inset
-\newline
+).
+ The simulator is built as part of the build process.
+ For more information visit Daniel's website at:
+\begin_inset LatexCommand \url{http://mazsola.iit.uni-miskolc.hu/~drdani/embedded/s51}
-\newline
-In this case the address arithmetic a->b[i] will be computed only once;
- the equivalent code in C would be.
-\newline
+\end_inset
+
+.
+ It currently support the core mcs51, the Dallas DS80C390 and the Philips
+ XA51 family.
+\layout Subsubsection
+
+sdcdb - Source Level Debugger
+\layout Standard
-\newline
\family typewriter
-iTemp = a->b[i];
+\shape italic
+<todo: is this thing still alive?>
\newline
-iTemp.c = 10;
+
\newline
-iTemp.d = 11;
+
\family default
+\shape default
+Sdcdb is the companion source level debugger.
+ The current version of the debugger uses Daniel's Simulator S51, but can
+ be easily changed to use other simulators.
+\layout Section
-\newline
+Using SDCC
+\layout Subsection
-\newline
-The compiler will try to keep these temporary variables in registers.
+Compiling
\layout Subsubsection
-Dead-Code Elimination
+Single Source File Projects
\layout Standard
+For single source file 8051 projects the process is very simple.
+ Compile your programs with the following command
+\family sans
+\series bold
+"sdcc sourcefile.c".
-\family typewriter
-int global;
-\newline
-void f () {
-\newline
-\SpecialChar ~
-\SpecialChar ~
-int i;
-\newline
-\SpecialChar ~
-\SpecialChar ~
-i = 1; \SpecialChar ~
-/* dead store */
+\family default
+\series default
+ This will compile, assemble and link your source file.
+ Output files are as follows
\newline
-\SpecialChar ~
-\SpecialChar ~
-global = 1;\SpecialChar ~
-/* dead store */
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-global = 2;
+sourcefile.asm
+\begin_inset LatexCommand \index{.asm}
+
+\end_inset
+
+ - Assembler source file created by the compiler
\newline
-\SpecialChar ~
-\SpecialChar ~
-return;
+sourcefile.lst
+\begin_inset LatexCommand \index{.lst}
+
+\end_inset
+
+ - Assembler listing file created by the Assembler
\newline
-\SpecialChar ~
-\SpecialChar ~
-global = 3;\SpecialChar ~
-/* unreachable */
+sourcefile.rst
+\begin_inset LatexCommand \index{.rst}
+
+\end_inset
+
+ - Assembler listing file updated with linkedit information, created by
+ linkage editor
\newline
-}
-\family default
+sourcefile.sym
+\begin_inset LatexCommand \index{.sym}
+
+\end_inset
+ - symbol listing for the sourcefile, created by the assembler
\newline
+sourcefile.rel
+\begin_inset LatexCommand \index{.rel}
+
+\end_inset
+ - Object file created by the assembler, input to Linkage editor
\newline
-will be changed to
+sourcefile.map
+\begin_inset LatexCommand \index{.map}
+
+\end_inset
+
+ - The memory map for the load module, created by the Linker
\newline
+sourcefile.mem
+\begin_inset LatexCommand \index{.mem}
+
+\end_inset
+ - A file with a summary of the memory ussage
\newline
+sourcefile.ihx
+\begin_inset LatexCommand \index{.ihx}
-\family typewriter
-int global; void f ()
+\end_inset
+
+ - The load module in Intel hex format (you can select the Motorola S19
+ format with ---out-fmt-s19)
\newline
-{
+sourcefile.adb
+\begin_inset LatexCommand \index{.adb}
+
+\end_inset
+
+ - An intermediate file containing debug information needed to create the
+ .cdb file (with ---debug)
\newline
-\SpecialChar ~
-\SpecialChar ~
-global = 2;
+sourcefile.cdb
+\begin_inset LatexCommand \index{.cdb}
+
+\end_inset
+
+ - An optional file (with ---debug) containing debug information
\newline
-\SpecialChar ~
-\SpecialChar ~
-return;
+sourcefile.
+ - (no extension)
+\begin_inset LatexCommand \index{. (no extension)}
+
+\end_inset
+
+ An optional AOMF51 file containing debug information (with ---debug)
\newline
-}
+sourcefile.dump*
+\begin_inset LatexCommand \index{.dump*}
+
+\end_inset
+
+ - Dump file to debug the compiler it self (with ---dumpall) (see section
+
+\begin_inset Quotes sld
+\end_inset
+
+Anatomy of the compiler
+\begin_inset Quotes srd
+\end_inset
+
+).
\layout Subsubsection
-Copy-Propagation
+Projects with Multiple Source Files
\layout Standard
-
-\family typewriter
-int f() {
+SDCC can compile only ONE file at a time.
+ Let us for example assume that you have a project containing the following
+ files:
\newline
-\SpecialChar ~
-\SpecialChar ~
-int i, j;
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-i = 10;
+foo1.c (contains some functions)
\newline
-\SpecialChar ~
-\SpecialChar ~
-j = i;
+foo2.c (contains some more functions)
\newline
-\SpecialChar ~
-\SpecialChar ~
-return j;
+foomain.c (contains more functions and the function main)
\newline
-}
-\family default
-\newline
+\size footnotesize
-\newline
-will be changed to
\newline
-\newline
+\size default
+The first two files will need to be compiled separately with the commands:
+\size footnotesize
+
+\size default
-\family typewriter
-int f() {
-\newline
-\SpecialChar ~
- \SpecialChar ~
- int i,j;
-\newline
-\SpecialChar ~
- \SpecialChar ~
- i = 10;
-\newline
-\SpecialChar ~
- \SpecialChar ~
- j = 10;
-\newline
-\SpecialChar ~
- \SpecialChar ~
- return 10;
-\newline
-}
\newline
\newline
+\family sans
+\series bold
+sdcc\SpecialChar ~
+-c\SpecialChar ~
+foo1.c
\family default
-Note: the dead stores created by this copy propagation will be eliminated
- by dead-code elimination.
-\layout Subsubsection
-
-Loop Optimizations
-\layout Standard
-
-Two types of loop optimizations are done by SDCC loop invariant lifting
- and strength reduction of loop induction variables.
- In addition to the strength reduction the optimizer marks the induction
- variables and the register allocator tries to keep the induction variables
- in registers for the duration of the loop.
- Because of this preference of the register allocator, loop induction optimizati
-on causes an increase in register pressure, which may cause unwanted spilling
- of other temporary variables into the stack / data space.
- The compiler will generate a warning message when it is forced to allocate
- extra space either on the stack or data space.
- If this extra space allocation is undesirable then induction optimization
- can be eliminated either for the entire source file (with --noinduction
- option) or for a given function only using #pragma\SpecialChar ~
-NOINDUCTION.
-\newline
-
-\newline
-Loop Invariant:
-\newline
+\series default
+\size footnotesize
\newline
-\family typewriter
-for (i = 0 ; i < 100 ; i ++)
-\newline
- \SpecialChar ~
- \SpecialChar ~
-f += k + l;
+\family sans
+\series bold
+\size default
+sdcc\SpecialChar ~
+-c\SpecialChar ~
+foo2.c
\family default
+\series default
\newline
\newline
-changed to
+Then compile the source file containing the
+\emph on
+main()
+\emph default
+ function and link the files together with the following command:
\newline
\newline
-\family typewriter
-itemp = k + l;
-\newline
-for (i = 0; i < 100; i++)
-\newline
-\SpecialChar ~
-\SpecialChar ~
-f += itemp;
+\family sans
+\series bold
+sdcc\SpecialChar ~
+foomain.c\SpecialChar ~
+foo1.rel\SpecialChar ~
+foo2.rel
\family default
+\series default
\newline
\newline
-As mentioned previously some loop invariants are not as apparent, all static
- address computations are also moved out of the loop.
+Alternatively,
+\emph on
+foomain.c
+\emph default
+can be separately compiled as well:
+\family sans
+\series bold
+
\newline
\newline
-Strength Reduction, this optimization substitutes an expression by a cheaper
- expression:
+sdcc\SpecialChar ~
+-c\SpecialChar ~
+foomain.c
\newline
-
+sdcc foomain.rel foo1.rel foo2.rel
\newline
-\family typewriter
-for (i=0;i < 100; i++)
\newline
-\SpecialChar ~
-\SpecialChar ~
-ar[i*5] = i*3;
+
\family default
+\series default
+The file containing the
+\emph on
+main()
+\emph default
+ function
+\emph on
+
+\emph default
+\noun on
+must
+\noun default
+ be the
+\noun on
+first
+\noun default
+ file specified in the command line, since the linkage editor processes
+ file in the order they are presented to it.
+\layout Subsubsection
-\newline
+Projects with Additional Libraries
+\begin_inset LatexCommand \index{Libraries}
-\newline
-changed to
-\newline
+\end_inset
-\newline
-\family typewriter
-itemp1 = 0;
-\newline
-itemp2 = 0;
-\newline
-for (i=0;i< 100;i++) {
+\layout Standard
+
+Some reusable routines may be compiled into a library, see the documentation
+ for the assembler and linkage editor (which are in <installdir>/share/sdcc/doc)
+ for how to create a
+\emph on
+.lib
+\begin_inset LatexCommand \index{.lib}
+
+\end_inset
+
+
+\emph default
+ library file.
+ Libraries created in this manner can be included in the command line.
+ Make sure you include the -L <library-path> option to tell the linker where
+ to look for these files if they are not in the current directory.
+ Here is an example, assuming you have the source file
+\emph on
+foomain.c
+\emph default
+ and a library
+\emph on
+ foolib.lib
+\emph default
+ in the directory
+\emph on
+mylib
+\emph default
+ (if that is not the same as your current project):
\newline
- \SpecialChar ~
- \SpecialChar ~
-ar[itemp1] = itemp2;
+
\newline
- \SpecialChar ~
- \SpecialChar ~
-itemp1 += 5;
+
+\family sans
+\series bold
+sdcc foomain.c foolib.lib -L mylib
\newline
- \SpecialChar ~
- \SpecialChar ~
-itemp2 += 3;
+
\newline
-}
-\family default
+\family default
+\series default
+Note here that
+\emph on
+ mylib
+\emph default
+ must be an absolute path name.
\newline
\newline
-The more expensive multiplication is changed to a less expensive addition.
-\layout Subsubsection
+The most efficient way to use libraries is to keep seperate modules in seperate
+ source files.
+ The lib file now should name all the modules.rel files.
+ For an example see the standard library file
+\emph on
+libsdcc.lib
+\emph default
+ in the directory <installdir>/share/lib/small.
+\layout Subsection
-Loop Reversing
-\layout Standard
+Command Line Options
+\begin_inset LatexCommand \index{Command Line Options}
-This optimization is done to reduce the overhead of checking loop boundaries
- for every iteration.
- Some simple loops can be reversed and implemented using a
-\begin_inset Quotes eld
\end_inset
-decrement and jump if not zero
-\begin_inset Quotes erd
-\end_inset
- instruction.
- SDCC checks for the following criterion to determine if a loop is reversible
- (note: more sophisticated compilers use data-dependency analysis to make
- this determination, SDCC uses a more simple minded analysis).
-\layout Itemize
+\layout Subsubsection
-The 'for' loop is of the form
-\newline
+Processor Selection Options
+\begin_inset LatexCommand \index{Processor Selection Options}
-\newline
+\end_inset
-\family typewriter
-for (<symbol> = <expression> ; <sym> [< | <=] <expression> ; [<sym>++ |
- <sym> += 1])
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-<for body>
-\layout Itemize
-The <for body> does not contain
-\begin_inset Quotes eld
-\end_inset
+\layout List
+\labelwidthstring 00.00.0000
-continue
-\begin_inset Quotes erd
-\end_inset
- or 'break
-\begin_inset Quotes erd
+\series bold
+-mmcs51
+\begin_inset LatexCommand \index{-mmcs51}
+
\end_inset
-.
-\layout Itemize
-All goto's are contained within the loop.
-\layout Itemize
+\series default
+ Generate code for the MCS51 (8051) family of processors.
+ This is the default processor target.
+\layout List
+\labelwidthstring 00.00.0000
-No function calls within the loop.
-\layout Itemize
-The loop control variable <sym> is not assigned any value within the loop
-\layout Itemize
+\series bold
+-mds390
+\begin_inset LatexCommand \index{-mds390}
-The loop control variable does NOT participate in any arithmetic operation
- within the loop.
-\layout Itemize
+\end_inset
-There are NO switch statements in the loop.
-\layout Standard
-Note djnz instruction can be used for 8-bit values
-\emph on
-only
-\emph default
-, therefore it is advantageous to declare loop control symbols as
-\emph on
-char
-\emph default
-.
- Ofcourse this may not be possible on all situations.
-\layout Subsubsection
+\series default
+ Generate code for the DS80C390 processor.
+\layout List
+\labelwidthstring 00.00.0000
-Algebraic Simplifications
-\layout Standard
-SDCC does numerous algebraic simplifications, the following is a small sub-set
- of these optimizations.
-\newline
+\series bold
+-mz80
+\begin_inset LatexCommand \index{-mz80}
-\newline
+\end_inset
-\family typewriter
-i = j + 0 ; /* changed to */ i = j;
-\newline
-i /= 2; /* changed to */ i >>= 1;
-\newline
-i = j - j ; /* changed to */ i = 0;
-\newline
-i = j / 1 ; /* changed to */ i = j;
-\family default
-\newline
-
-\newline
-Note the subexpressions given above are generally introduced by macro expansions
- or as a result of copy/constant propagation.
-\layout Subsubsection
+\series default
+ Generate code for the Z80 family of processors.
+\layout List
+\labelwidthstring 00.00.0000
-'switch' Statements
-\layout Standard
-SDCC changes switch statements to jump tables when the following conditions
- are true.
-
-\layout Itemize
+\series bold
+-mgbz80
+\begin_inset LatexCommand \index{-mgbz80}
-The case labels are in numerical sequence, the labels need not be in order,
- and the starting number need not be one or zero.
-\newline
+\end_inset
-\newline
-\family typewriter
-switch(i) {\SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
-switch (i) {
-\newline
-case 4:...
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
-case 1: ...
-
-\newline
-case 5:...
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
-case 2: ...
-
-\newline
-case 3:...
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
-case 3: ...
-
-\newline
-case 6:...
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
-case 4: ...
-
-\newline
-}\SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
-}
-\newline
+\series default
+ Generate code for the GameBoy Z80 processor.
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-\family default
-Both the above switch statements will be implemented using a jump-table.
-\layout Itemize
+\series bold
+-mavr
+\begin_inset LatexCommand \index{-mavr}
-The number of case labels is at least three, since it takes two conditional
- statements to handle the boundary conditions.
-\layout Itemize
+\end_inset
-The number of case labels is less than 84, since each label takes 3 bytes
- and a jump-table can be utmost 256 bytes long.
-
-\layout Standard
-Switch statements which have gaps in the numeric sequence or those that
- have more that 84 case labels can be split into more than one switch statement
- for efficient code generation, e.g.:
-\newline
+\series default
+ Generate code for the Atmel AVR processor (In development, not complete).
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-\family typewriter
-switch (i) {
-\newline
-case 1: ...
-
-\newline
-case 2: ...
-
-\newline
-case 3: ...
-
-\newline
-case 4: ...
-
-\newline
-case 9: ...
-
-\newline
-case 10: ...
-
-\newline
-case 11: ...
-
-\newline
-case 12: ...
-
-\newline
-}
-\family default
+\series bold
+-mpic14
+\begin_inset LatexCommand \index{-mpic14}
-\newline
+\end_inset
-\newline
-If the above switch statement is broken down into two switch statements
-\newline
-\newline
+\series default
+ Generate code for the PIC 14-bit processors (In development, not complete).
+\layout List
+\labelwidthstring 00.00.0000
-\family typewriter
-switch (i) {
-\newline
-case 1: ...
-
-\newline
-case 2: ...
-
-\newline
-case 3: ...
-
-\newline
-case 4: ...
-
-\newline
-}
-\newline
-\newline
+\series bold
+-mtlcs900h
+\series default
+ Generate code for the Toshiba TLCS-900H processor (In development, not
+ complete).
+\layout List
+\labelwidthstring 00.00.0000
-\family default
-and
-\family typewriter
-\newline
+\series bold
+-mxa51
+\begin_inset LatexCommand \index{-mxa51}
-\newline
-switch (i) {
-\newline
-case 9: \SpecialChar ~
-...
-
-\newline
-case 10: ...
-
-\newline
-case 11: ...
-
-\newline
-case 12:\SpecialChar ~
-...
-
-\newline
-}
-\newline
+\end_inset
-\newline
-\family default
-then both the switch statements will be implemented using jump-tables whereas
- the unmodified switch statement will not be.
+\series default
+ Generate code for the Philips XA51 processor (In development, not complete).
\layout Subsubsection
-Bit-shifting Operations.
-\layout Standard
+Preprocessor Options
+\begin_inset LatexCommand \index{Options Preprocessor}
-Bit shifting is one of the most frequently used operation in embedded programmin
-g.
- SDCC tries to implement bit-shift operations in the most efficient way
- possible, e.g.:
-\newline
+\end_inset
-\family typewriter
-\newline
-unsigned char i;
-\newline
-...
-
-\newline
-i>>= 4;
-\newline
-...
-\newline
+\begin_inset LatexCommand \index{Preprocessor Options}
-\family default
+\end_inset
-\newline
-generates the following code:
-\newline
-\family typewriter
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-mov a,_i
-\newline
-swap a
-\newline
-anl a,#0x0f
-\newline
-mov _i,a
-\family default
-\newline
+\series bold
+-I<path>
+\begin_inset LatexCommand \index{-I<path>}
-\newline
-In general SDCC will never setup a loop if the shift count is known.
- Another example:
-\newline
+\end_inset
-\newline
-\family typewriter
-unsigned int i;
-\newline
-...
-
-\newline
-i >>= 9;
-\newline
-...
-\family default
+\series default
+ The additional location where the pre processor will look for <..h> or
+\begin_inset Quotes eld
+\end_inset
-\newline
+..h
+\begin_inset Quotes erd
+\end_inset
-\newline
-will generate:
-\newline
+ files.
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-\family typewriter
-mov a,(_i + 1)
-\newline
-mov (_i + 1),#0x00
-\newline
-clr c
-\newline
-rrc a
-\newline
-mov _i,a
-\family default
+\series bold
+-D<macro[=value]>
+\begin_inset LatexCommand \index{-D<macro[=value]>}
-\newline
+\end_inset
-\newline
-Note that SDCC stores numbers in little-endian format (i.e.
- lowest order first).
-\layout Subsubsection
-Bit-rotation
-\layout Standard
+\series default
+ Command line definition of macros.
+ Passed to the pre processor.
+\layout List
+\labelwidthstring 00.00.0000
-A special case of the bit-shift operation is bit rotation, SDCC recognizes
- the following expression to be a left bit-rotation:
-\newline
-\newline
+\series bold
+-M
+\begin_inset LatexCommand \index{-M}
-\family typewriter
-unsigned char i;
-\newline
-...
-
-\newline
-i = ((i << 1) | (i >> 7));
-\family default
+\end_inset
-\newline
-...
-\newline
-\newline
-will generate the following code:
-\newline
+\series default
+ Tell the preprocessor to output a rule suitable for make describing the
+ dependencies of each object file.
+ For each source file, the preprocessor outputs one make-rule whose target
+ is the object file name for that source file and whose dependencies are
+ all the files `#include'd in it.
+ This rule may be a single line or may be continued with `
+\backslash
+'-newline if it is long.
+ The list of rules is printed on standard output instead of the preprocessed
+ C program.
+ `-M' implies `-E'.
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-\family typewriter
-mov a,_i
-\newline
-rl a
-\newline
-mov _i,a
-\family default
+\series bold
+-C
+\begin_inset LatexCommand \index{-C}
-\newline
+\end_inset
-\newline
-SDCC uses pattern matching on the parse tree to determine this operation.Variatio
-ns of this case will also be recognized as bit-rotation, i.e.:
-\newline
-\newline
+\series default
+ Tell the preprocessor not to discard comments.
+ Used with the `-E' option.
+\layout List
+\labelwidthstring 00.00.0000
-\family typewriter
-i = ((i >> 7) | (i << 1)); /* left-bit rotation */
-\layout Subsubsection
-Highest Order Bit
-\layout Standard
+\series bold
+-MM
+\begin_inset LatexCommand \index{-MM}
-It is frequently required to obtain the highest order bit of an integral
- type (long, int, short or char types).
- SDCC recognizes the following expression to yield the highest order bit
- and generates optimized code for it, e.g.:
-\newline
+\end_inset
-\newline
-
-\family typewriter
-unsigned int gint;
-\newline
-\newline
-foo () {
-\newline
-unsigned char hob;
-\newline
-\SpecialChar ~
-\SpecialChar ~
-...
-
-\newline
-\SpecialChar ~
-\SpecialChar ~
-hob = (gint >> 15) & 1;
-\newline
-\SpecialChar ~
-\SpecialChar ~
-..
+\size large
+\bar under
-\newline
-}
-\family default
+\series default
+\size default
+\bar default
+Like `-M' but the output mentions only the user header files included with
+ `#include
+\begin_inset Quotes eld
+\end_inset
-\newline
+file"'.
+ System header files included with `#include <file>' are omitted.
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-will generate the following code:
-\newline
-\family typewriter
+\series bold
+-Aquestion(answer)
+\begin_inset LatexCommand \index{-Aquestion(answer)}
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- 61 ;\SpecialChar ~
- hob.c 7
-\newline
-\SpecialChar ~
-\SpecialChar ~
- 000A E5*01\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- 62\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- mov\SpecialChar ~
- a,(_gint + 1)
-\newline
-\SpecialChar ~
-\SpecialChar ~
- 000C 33\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- 63\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- rlc\SpecialChar ~
- a
-\newline
-\SpecialChar ~
-\SpecialChar ~
- 000D E4\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- 64\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- clr\SpecialChar ~
- a
-\newline
-\SpecialChar ~
-\SpecialChar ~
- 000E 13\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- 65\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- rrc\SpecialChar ~
- a
-\newline
-\SpecialChar ~
-\SpecialChar ~
- 000F F5*02\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- 66\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- mov\SpecialChar ~
- _foo_hob_1_1,a
-\newline
+\end_inset
-\newline
-\family default
-Variations of this case however will
-\emph on
-not
-\emph default
- be recognized.
- It is a standard C expression, so I heartily recommend this be the only
- way to get the highest order bit, (it is portable).
- Of course it will be recognized even if it is embedded in other expressions,
- e.g.:
-\newline
+\series default
+ Assert the answer answer for question, in case it is tested with a preprocessor
+ conditional such as `#if #question(answer)'.
+ `-A-' disables the standard assertions that normally describe the target
+ machine.
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-\family typewriter
-xyz = gint + ((gint >> 15) & 1);
-\family default
+\series bold
+-Aquestion
+\series default
+ (answer) Assert the answer answer for question, in case it is tested with
+ a preprocessor conditional such as `#if #question(answer)'.
+ `-A-' disables the standard assertions that normally describe the target
+ machine.
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-\newline
-will still be recognized.
-\layout Subsubsection
+\series bold
+-Umacro
+\begin_inset LatexCommand \index{-Umacro}
-Peep-hole Optimizer
-\layout Standard
+\end_inset
-The compiler uses a rule based, pattern matching and re-writing mechanism
- for peep-hole optimization.
- It is inspired by
-\emph on
-copt
-\emph default
- a peep-hole optimizer by Christopher W.
- Fraser (cwfraser@microsoft.com).
- A default set of rules are compiled into the compiler, additional rules
- may be added with the
-\emph on
---peep-file <filename>
-\emph default
- option.
- The rule language is best illustrated with examples.
-\newline
-\newline
+\series default
+ Undefine macro macro.
+ `-U' options are evaluated after all `-D' options, but before any `-include'
+ and `-imacros' options.
+\layout List
+\labelwidthstring 00.00.0000
-\family typewriter
-replace {
-\newline
-\SpecialChar ~
-\SpecialChar ~
-mov %1,a
-\newline
-\SpecialChar ~
-\SpecialChar ~
-mov a,%1
-\newline
-} by {
-\newline
-\SpecialChar ~
-\SpecialChar ~
-mov %1,a
-\newline
-}
-\family default
-\newline
+\series bold
+-dM
+\begin_inset LatexCommand \index{-dM}
-\newline
-The above rule will change the following assembly sequence:
-\newline
+\end_inset
-\newline
-\family typewriter
-\SpecialChar ~
-\SpecialChar ~
-mov r1,a
-\newline
-\SpecialChar ~
-\SpecialChar ~
-mov a,r1
-\family default
+\series default
+ Tell the preprocessor to output only a list of the macro definitions that
+ are in effect at the end of preprocessing.
+ Used with the `-E' option.
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-\newline
-to
-\newline
+\series bold
+-dD
+\begin_inset LatexCommand \index{-dD}
-\newline
+\end_inset
-\family typewriter
-mov r1,a
-\family default
-\newline
+\series default
+ Tell the preprocessor to pass all macro definitions into the output, in
+ their proper sequence in the rest of the output.
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-Note: All occurrences of a
-\emph on
-%n
-\emph default
- (pattern variable) must denote the same string.
- With the above rule, the assembly sequence:
-\newline
-\newline
+\series bold
+-dN
+\begin_inset LatexCommand \index{-dN}
-\family typewriter
-\SpecialChar ~
-\SpecialChar ~
-mov r1,a
-\newline
-\SpecialChar ~
-\SpecialChar ~
-mov a,r2
-\family default
+\end_inset
-\newline
-\newline
-will remain unmodified.
-\newline
+\size large
+\bar under
+
+\series default
+\size default
+\bar default
+Like `-dD' except that the macro arguments and contents are omitted.
+ Only `#define name' is included in the output.
+\layout Subsubsection
-\newline
-Other special case optimizations may be added by the user (via
-\emph on
---peep-file option
-\emph default
-).
- E.g.
- some variants of the 8051 MCU allow only
-\family typewriter
-ajmp
-\family default
- and
-\family typewriter
-acall
-\family default
-.
- The following two rules will change all
-\family typewriter
-ljmp
-\family default
- and
-\family typewriter
-lcall
-\family default
- to
-\family typewriter
-ajmp
-\family default
- and
-\family typewriter
-acall
-\family default
+Linker Options
+\begin_inset LatexCommand \index{Options Linker}
-\newline
+\end_inset
-\newline
-\family typewriter
-replace { lcall %1 } by { acall %1 }
-\newline
-replace { ljmp %1 } by { ajmp %1 }
-\family default
+\begin_inset LatexCommand \index{Linker Options}
-\newline
+\end_inset
-\newline
-The
-\emph on
-inline-assembler code
-\emph default
- is also passed through the peep hole optimizer, thus the peephole optimizer
- can also be used as an assembly level macro expander.
- The rules themselves are MCU dependent whereas the rule language infra-structur
-e is MCU independent.
- Peephole optimization rules for other MCU can be easily programmed using
- the rule language.
-\newline
-\newline
-The syntax for a rule is as follows:
-\newline
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-\family typewriter
-rule := replace [ restart ] '{' <assembly sequence> '
-\backslash
-n'
-\newline
-\SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- '}' by '{' '
-\backslash
-n'
-\newline
-\SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- <assembly sequence> '
-\backslash
-n'
-\newline
-\SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
- '}' [if <functionName> ] '
-\backslash
-n'
-\newline
+\series bold
+-L\SpecialChar ~
+---lib-path
+\begin_inset LatexCommand \index{-L ---lib-path}
-\family default
+\end_inset
-\newline
-<assembly sequence> := assembly instruction (each instruction including
- labels must be on a separate line).
-\newline
-\newline
-The optimizer will apply to the rules one by one from the top in the sequence
- of their appearance, it will terminate when all rules are exhausted.
- If the 'restart' option is specified, then the optimizer will start matching
- the rules again from the top, this option for a rule is expensive (performance)
-, it is intended to be used in situations where a transformation will trigger
- the same rule again.
- A good example of this the following rule:
-\newline
+\bar under
+
+\series default
+\bar default
+<absolute path to additional libraries> This option is passed to the linkage
+ editor's additional libraries search path.
+ The path name must be absolute.
+ Additional library files may be specified in the command line.
+ See section Compiling programs for more details.
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-\family typewriter
-replace restart {
-\newline
-\SpecialChar ~
-\SpecialChar ~
-pop %1
-\newline
-\SpecialChar ~
-\SpecialChar ~
-push %1 } by {
-\newline
-\SpecialChar ~
-\SpecialChar ~
-; nop
-\newline
-}
-\family default
+\series bold
+---xram-loc
+\series default
-\newline
+\begin_inset LatexCommand \index{---xram-loc}
-\newline
-Note that the replace pattern cannot be a blank, but can be a comment line.
- Without the 'restart' option only the inner most 'pop' 'push' pair would
- be eliminated, i.e.:
-\newline
+\end_inset
-\newline
+<Value> The start location of the external ram, default value is 0.
+ The value entered can be in Hexadecimal or Decimal format, e.g.: ---xram-loc
+ 0x8000 or ---xram-loc 32768.
+\layout List
+\labelwidthstring 00.00.0000
-\family typewriter
-\SpecialChar ~
-\SpecialChar ~
-pop ar1
-\newline
-\SpecialChar ~
-\SpecialChar ~
-pop ar2
-\newline
-\SpecialChar ~
-\SpecialChar ~
-push ar2
-\newline
-\SpecialChar ~
-\SpecialChar ~
-push ar1
-\family default
-\newline
+\series bold
+---code-loc
+\series default
-\newline
-would result in:
-\newline
+\begin_inset LatexCommand \index{---code-loc}
-\newline
+\end_inset
-\family typewriter
-\SpecialChar ~
-\SpecialChar ~
-pop ar1
-\newline
-\SpecialChar ~
-\SpecialChar ~
-; nop
-\newline
-\SpecialChar ~
-\SpecialChar ~
-push ar1
-\family default
+<Value> The start location of the code segment, default value 0.
+ Note when this option is used the interrupt vector table is also relocated
+ to the given address.
+ The value entered can be in Hexadecimal or Decimal format, e.g.: ---code-loc
+ 0x8000 or ---code-loc 32768.
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-\newline
+\series bold
+---stack-loc
+\series default
-\emph on
-with
-\emph default
- the restart option the rule will be applied again to the resulting code
- and then all the pop-push pairs will be eliminated to yield:
-\newline
+\begin_inset LatexCommand \index{---stack-loc}
-\newline
+\end_inset
-\family typewriter
-\SpecialChar ~
-\SpecialChar ~
-; nop
-\newline
-\SpecialChar ~
-\SpecialChar ~
-; nop
-\family default
+<Value> By default the stack is placed after the data segment.
+ Using this option the stack can be placed anywhere in the internal memory
+ space of the 8051.
+ The value entered can be in Hexadecimal or Decimal format, e.g.
+ ---stack-loc 0x20 or ---stack-loc 32.
+ Since the sp register is incremented before a push or call, the initial
+ sp will be set to one byte prior the provided value.
+ The provided value should not overlap any other memory areas such as used
+ register banks or the data segment and with enough space for the current
+ application.
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-\newline
-A conditional function can be attached to a rule.
- Attaching rules are somewhat more involved, let me illustrate this with
- an example.
-\newline
+\series bold
+---data-loc
+\series default
-\newline
+\begin_inset LatexCommand \index{---data-loc}
-\family typewriter
-replace {
-\newline
-\SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
-ljmp %5
-\newline
-%2:
-\newline
-} by {
-\newline
-\SpecialChar ~
- \SpecialChar ~
- \SpecialChar ~
-sjmp %5
-\newline
-%2:
-\newline
-} if labelInRange
-\family default
+\end_inset
-\newline
+<Value> The start location of the internal ram data segment.
+ The value entered can be in Hexadecimal or Decimal format, eg.
+ ---data-loc 0x20 or ---data-loc 32.
+ (By default, the start location of the internal ram data segment is set
+ as low as possible in memory, taking into account the used register banks
+ and the bit segment at address 0x20.
+ For example if register banks 0 and 1 are used without bit variables, the
+ data segment will be set, if ---data-loc is not used, to location 0x10.)
+\layout List
+\labelwidthstring 00.00.0000
-\newline
-The optimizer does a look-up of a function name table defined in function
-
-\emph on
-callFuncByName
-\emph default
- in the source file SDCCpeeph.c, with the name
-\emph on
-labelInRange
-\emph default
-.
- If it finds a corresponding entry the function is called.
- Note there can be no parameters specified for these functions, in this
- case the use of
-\emph on
-%5
-\emph default
- is crucial, since the function
-\emph on
-labelInRange
-\emph default
- expects to find the label in that particular variable (the hash table containin
-g the variable bindings is passed as a parameter).
- If you want to code more such functions, take a close look at the function
- labelInRange and the calling mechanism in source file SDCCpeeph.c.
- I know this whole thing is a little kludgey, but maybe some day we will
- have some better means.
- If you are looking at this file, you will also see the default rules that
- are compiled into the compiler, you can add your own rules in the default
- set there if you get tired of specifying the --peep-file option.
-\layout Subsection
-Pragmas
-\layout Standard
+\series bold
+---idata-loc
+\series default
-SDCC supports the following #pragma directives.
- This directives are applicable only at a function level.
-\layout Itemize
+\begin_inset LatexCommand \index{---idata-loc}
-SAVE - this will save all the current options.
-\layout Itemize
+\end_inset
-RESTORE - will restore the saved options from the last save.
- Note that SAVES & RESTOREs cannot be nested.
- SDCC uses the same buffer to save the options each time a SAVE is called.
-\layout Itemize
+<Value> The start location of the indirectly addressable internal ram, default
+ value is 0x80.
+ The value entered can be in Hexadecimal or Decimal format, eg.
+ ---idata-loc 0x88 or ---idata-loc 136.
+\layout List
+\labelwidthstring 00.00.0000
-NOGCSE - will stop global subexpression elimination.
-\layout Itemize
-NOINDUCTION - will stop loop induction optimizations.
-\layout Itemize
+\series bold
+---out-fmt-ihx
+\begin_inset LatexCommand \index{---out-fmt-ihx}
-NOJTBOUND - will not generate code for boundary value checking, when switch
- statements are turned into jump-tables.
-\layout Itemize
+\end_inset
-NOOVERLAY - the compiler will not overlay the parameters and local variables
- of a function.
-\layout Itemize
-NOLOOPREVERSE - Will not do loop reversal optimization
-\layout Itemize
+\bar under
+
+\series default
+\bar default
+The linker output (final object code) is in Intel Hex format.
+ (This is the default option).
+\layout List
+\labelwidthstring 00.00.0000
-EXCLUDE NONE | {acc[,b[,dpl[,dph]]] - The exclude pragma disables generation
- of pair of push/pop instruction in ISR function (using interrupt keyword).
- The directive should be placed immediately before the ISR function definition
- and it affects ALL ISR functions following it.
- To enable the normal register saving for ISR functions use #pragma\SpecialChar ~
-EXCLUDE\SpecialChar ~
-none.
-\layout Itemize
-CALLEE-SAVES function1[,function2[,function3...]] - The compiler by default
- uses a caller saves convention for register saving across function calls,
- however this can cause unneccessary register pushing & popping when calling
- small functions from larger functions.
- This option can be used to switch the register saving convention for the
- function names specified.
- The compiler will not save registers when calling these functions, extra
- code will be generated at the entry & exit for these functions to save
- & restore the registers used by these functions, this can SUBSTANTIALLY
- reduce code & improve run time performance of the generated code.
- In future the compiler (with interprocedural analysis) will be able to
- determine the appropriate scheme to use for each function call.
- If --callee-saves command line option is used, the function names specified
- in #pragma\SpecialChar ~
-CALLEE-SAVES is appended to the list of functions specified inthe
- command line.
-\layout Standard
+\series bold
+---out-fmt-s19
+\begin_inset LatexCommand \index{---out-fmt-s19}
-The pragma's are intended to be used to turn-off certain optimizations which
- might cause the compiler to generate extra stack / data space to store
- compiler generated temporary variables.
- This usually happens in large functions.
- Pragma directives should be used as shown in the following example, they
- are used to control options & optimizations for a given function; pragmas
- should be placed before and/or after a function, placing pragma's inside
- a function body could have unpredictable results.
-\newline
+\end_inset
-\newline
-\family typewriter
-#pragma SAVE /* save the current settings */
-\newline
-#pragma NOGCSE /* turnoff global subexpression elimination */
-\newline
-#pragma NOINDUCTION /* turn off induction optimizations */
-\newline
-int foo ()
-\newline
-{
-\newline
-\SpecialChar ~
- \SpecialChar ~
- ...
-
-\newline
-\SpecialChar ~
- \SpecialChar ~
- /* large code */
-\newline
-\SpecialChar ~
- \SpecialChar ~
- ...
+\bar under
-\newline
-}
-\newline
-#pragma RESTORE /* turn the optimizations back on */
-\family default
+\series default
+\bar default
+The linker output (final object code) is in Motorola S19 format.
+\layout Subsubsection
-\newline
+MCS51 Options
+\begin_inset LatexCommand \index{Options MCS51}
-\newline
-The compiler will generate a warning message when extra space is allocated.
- It is strongly recommended that the SAVE and RESTORE pragma's be used when
- changing options for a function.
-\layout Subsection
+\end_inset
+
+
+\begin_inset LatexCommand \index{MCS51 Options}
+
+\end_inset
+
+
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---model-large
+\begin_inset LatexCommand \index{---model-large}
+
+\end_inset
+
+
+\series default
+ Generate code for Large model programs see section Memory Models for more
+ details.
+ If this option is used all source files in the project should be compiled
+ with this option.
+ In addition the standard library routines are compiled with small model,
+ they will need to be recompiled.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---model-small
+\begin_inset LatexCommand \index{---model-small}
+
+\end_inset
+\series default
+\size large
\emph on
-<pending: this is messy and incomplete>
+
+\size default
\emph default
- Library Routines
-\layout Standard
+Generate code for Small Model programs see section Memory Models for more
+ details.
+ This is the default model.
+\layout Subsubsection
-The following library routines are provided for your convenience.
-\layout Standard
+DS390 Options
+\begin_inset LatexCommand \index{Options DS390}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{DS390 Options}
+
+\end_inset
+
+
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---model-flat24
+\series default
+
+\begin_inset LatexCommand \index{---model-flat24}
+
+\end_inset
-stdio.h - Contains the following functions printf & sprintf these routines
- are developed by Martijn van Balen <balen@natlab.research.philips.com>.
+
+\size large
+\emph on
-\layout Standard
+\size default
+\emph default
+Generate 24-bit flat mode code.
+ This is the one and only that the ds390 code generator supports right now
+ and is default when using
+\emph on
+-mds390
+\emph default
+.
+ See section Memory Models for more details.
+\layout List
+\labelwidthstring 00.00.0000
-%[flags][width][b|B|l|L]type
-\layout Standard
+\series bold
+---stack-10bit
+\series default
+
+\begin_inset LatexCommand \index{--stack-10bit}
+
+\end_inset
+
+ Generate code for the 10 bit stack mode of the Dallas DS80C390 part.
+ This is the one and only that the ds390 code generator supports right now
+ and is default when using
+\emph on
+-mds390
+\emph default
+.
+ In this mode, the stack is located in the lower 1K of the internal RAM,
+ which is mapped to 0x400000.
+ Note that the support is incomplete, since it still uses a single byte
+ as the stack pointer.
+ This means that only the lower 256 bytes of the potential 1K stack space
+ will actually be used.
+ However, this does allow you to reclaim the precious 256 bytes of low RAM
+ for use for the DATA and IDATA segments.
+ The compiler will not generate any code to put the processor into 10 bit
+ stack mode.
+ It is important to ensure that the processor is in this mode before calling
+ any re-entrant functions compiled with this option.
+ In principle, this should work with the
+\emph on
+---stack-auto
+\emph default
+ option, but that has not been tested.
+ It is incompatible with the
+\emph on
+---xstack
+\emph default
+ option.
+ It also only makes sense if the processor is in 24 bit contiguous addressing
+ mode (see the
+\emph on
+---model-flat24 option
+\emph default
+).
+\layout Subsubsection
+
+Optimization Options
+\begin_inset LatexCommand \index{Options Optimization}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{Optimization Options}
+
+\end_inset
+
+
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---nogcse
+\begin_inset LatexCommand \index{---nogcse}
+
+\end_inset
+
+
+\series default
+ Will not do global subexpression elimination, this option may be used when
+ the compiler creates undesirably large stack/data spaces to store compiler
+ temporaries.
+ A warning message will be generated when this happens and the compiler
+ will indicate the number of extra bytes it allocated.
+ It recommended that this option NOT be used, #pragma\SpecialChar ~
+NOGCSE can be used
+ to turn off global subexpression elimination for a given function only.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---noinvariant
+\begin_inset LatexCommand \index{---noinvariant}
+
+\end_inset
+
+
+\series default
+ Will not do loop invariant optimizations, this may be turned off for reasons
+ explained for the previous option.
+ For more details of loop optimizations performed see section Loop Invariants.It
+ recommended that this option NOT be used, #pragma\SpecialChar ~
+NOINVARIANT can be used
+ to turn off invariant optimizations for a given function only.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---noinduction
+\begin_inset LatexCommand \index{---noinduction}
+
+\end_inset
+
+
+\series default
+ Will not do loop induction optimizations, see section strength reduction
+ for more details.It is recommended that this option is NOT used, #pragma\SpecialChar ~
+NOINDUCT
+ION can be used to turn off induction optimizations for a given function
+ only.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---nojtbound
+\begin_inset LatexCommand \index{---nojtbound}
+
+\end_inset
+
+
+\size large
+\bar under
+
+\series default
+\size default
+\bar default
+ Will not generate boundary condition check when switch statements are implement
+ed using jump-tables.
+ See section Switch Statements for more details.
+ It is recommended that this option is NOT used, #pragma\SpecialChar ~
+NOJTBOUND can be
+ used to turn off boundary checking for jump tables for a given function
+ only.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---noloopreverse
+\begin_inset LatexCommand \index{---noloopreverse}
+
+\end_inset
+
+
+\series default
+\size large
+
+\size default
+Will not do loop reversal optimization.
+\layout List
+\labelwidthstring 00.00.0000
+
+---
+\series bold
+nolabelopt
+\series default
+
+\begin_inset LatexCommand \index{---nolabelopt }
+
+\end_inset
+
+Will not optimize labels (makes the dumpfiles more readable).
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---no-xinit-opt
+\begin_inset LatexCommand \index{---no-xinit-opt}
+
+\end_inset
+
+
+\series default
+ Will not memcpy initialized data in far space from code space.
+ This saves a few bytes in code space if you don't have initialized data.
+\layout Subsubsection
+
+Other Options
+\begin_inset LatexCommand \index{Options other}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{Other Options}
+
+\end_inset
+
+
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+-c\SpecialChar ~
+---compile-only
+\begin_inset LatexCommand \index{---compile-only}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{-c ---compile-only}
+
+\end_inset
+
+
+\series default
+ will compile and assemble the source, but will not call the linkage editor.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+--c1mode
+\begin_inset LatexCommand \index{--c1mode}
+
+\end_inset
+
+
+\series default
+ reads the preprocessed source from standard input and compiles it.
+ The file name for the assembler output must be specified using the -o option.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+-E
+\begin_inset LatexCommand \index{-E}
+
+\end_inset
+
+
+\series default
+ Run only the C preprocessor.
+ Preprocess all the C source files specified and output the results to standard
+ output.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+-o\SpecialChar ~
+<path/file>
+\begin_inset LatexCommand \index{-o <path/file>}
+
+\end_inset
+
+
+\series default
+The output path resp.
+ file where everything will be placed.
+ If the parameter is a path, it must have a trailing slash (or backslash
+ for the Windows binaries) to be recognized as a path.
+
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---stack-auto
+\begin_inset LatexCommand \index{---stack-auto}
+
+\end_inset
+
+
+\series default
+\size large
+\emph on
+
+\size default
+\emph default
+All functions in the source file will be compiled as
+\emph on
+reentrant
+\emph default
+, i.e.
+ the parameters and local variables will be allocated on the stack.
+ see section Parameters and Local Variables for more details.
+ If this option is used all source files in the project should be compiled
+ with this option.
+
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---xstack
+\begin_inset LatexCommand \index{---xstack}
+
+\end_inset
+
+
+\series default
+ Uses a pseudo stack in the first 256 bytes in the external ram for allocating
+ variables and passing parameters.
+ See section on external stack for more details.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---callee-saves
+\begin_inset LatexCommand \index{---callee-saves}
+
+\end_inset
+
+ function1[,function2][,function3]....
+
+\series default
+ The compiler by default uses a caller saves convention for register saving
+ across function calls, however this can cause unneccessary register pushing
+ & popping when calling small functions from larger functions.
+ This option can be used to switch the register saving convention for the
+ function names specified.
+ The compiler will not save registers when calling these functions, no extra
+ code will be generated at the entry & exit for these functions to save
+ & restore the registers used by these functions, this can SUBSTANTIALLY
+ reduce code & improve run time performance of the generated code.
+ In the future the compiler (with interprocedural analysis) will be able
+ to determine the appropriate scheme to use for each function call.
+ DO NOT use this option for built-in functions such as _muluint..., if this
+ option is used for a library function the appropriate library function
+ needs to be recompiled with the same option.
+ If the project consists of multiple source files then all the source file
+ should be compiled with the same ---callee-saves option string.
+ Also see #pragma\SpecialChar ~
+CALLEE-SAVES
+\begin_inset LatexCommand \index{\#pragma CALLEE-SAVES}
+
+\end_inset
+
+.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---debug
+\begin_inset LatexCommand \index{---debug}
+
+\end_inset
+
+
+\bar under
+
+\series default
+\bar default
+When this option is used the compiler will generate debug information, that
+ can be used with the SDCDB.
+ The debug information is collected in a file with .cdb extension.
+ For more information see documentation for SDCDB.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---peep-file
+\series default
+
+\begin_inset LatexCommand \index{---peep-file}
+
+\end_inset
+
+<filename> This option can be used to use additional rules to be used by
+ the peep hole optimizer.
+ See section Peep Hole optimizations for details on how to write these rules.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+-S
+\begin_inset LatexCommand \index{-S}
+
+\end_inset
+
+
+\size large
+\bar under
+
+\series default
+\size default
+\bar default
+Stop after the stage of compilation proper; do not assemble.
+ The output is an assembler code file for the input file specified.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+-Wa_asmOption[,asmOption]
+\series default
+
+\begin_inset LatexCommand \index{-Wa\_asmOption[,asmOption]}
+
+\end_inset
+
+...
+ Pass the asmOption to the assembler.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+-Wl_linkOption[,linkOption]
+\series default
+
+\begin_inset LatexCommand \index{-Wl\_linkOption[,linkOption]}
+
+\end_inset
+
+...
+ Pass the linkOption to the linker.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---int-long-reent
+\begin_inset LatexCommand \index{---int-long-reent}
+
+\end_inset
+
+
+\series default
+ Integer (16 bit) and long (32 bit) libraries have been compiled as reentrant.
+ Note by default these libraries are compiled as non-reentrant.
+ See section Installation for more details.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---cyclomatic
+\begin_inset LatexCommand \index{---cyclomatic}
+
+\end_inset
+
+
+\bar under
+
+\series default
+\bar default
+This option will cause the compiler to generate an information message for
+ each function in the source file.
+ The message contains some
+\emph on
+important
+\emph default
+ information about the function.
+ The number of edges and nodes the compiler detected in the control flow
+ graph of the function, and most importantly the
+\emph on
+cyclomatic complexity
+\begin_inset LatexCommand \index{cyclomatic complexity}
+
+\end_inset
+
+
+\emph default
+ see section on Cyclomatic Complexity for more details.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---float-reent
+\begin_inset LatexCommand \index{---float-reent}
+
+\end_inset
+
+
+\bar under
+
+\series default
+\bar default
+ Floating point library is compiled as reentrant
+\begin_inset LatexCommand \index{ reentrant}
+
+\end_inset
+
+.See section Installation for more details.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---nooverlay
+\begin_inset LatexCommand \index{---nooverlay}
+
+\end_inset
+
+
+\series default
+ The compiler will not overlay parameters and local variables of any function,
+ see section Parameters and local variables for more details.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---main-return
+\begin_inset LatexCommand \index{---main-return}
+
+\end_inset
+
+
+\series default
+ This option can be used when the code generated is called by a monitor
+ program.
+ The compiler will generate a 'ret' upon return from the 'main'
+\begin_inset LatexCommand \index{main return}
+
+\end_inset
+
+ function.
+ The default option is to lock up i.e.
+ generate a 'ljmp '.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---no-peep
+\begin_inset LatexCommand \index{---no-peep}
+
+\end_inset
+
+
+\series default
+ Disable peep-hole optimization.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---peep-asm
+\begin_inset LatexCommand \index{---peep-asm}
+
+\end_inset
+
+
+\series default
+ Pass the inline assembler code through the peep hole optimizer.
+ This can cause unexpected changes to inline assembler code, please go through
+ the peephole optimizer
+\begin_inset LatexCommand \index{Peephole optimizer}
+
+\end_inset
+
+ rules defined in the source file tree '<target>/peeph.def' before using
+ this option.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---iram-size
+\series default
+<Value>
+\begin_inset LatexCommand \index{---iram-size<Value>}
+
+\end_inset
+
+ Causes the linker to check if the internal ram usage is within limits of
+ the given value.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---xram-size
+\series default
+<Value>
+\begin_inset LatexCommand \index{---xram-size<Value>}
+
+\end_inset
+
+ Causes the linker to check if the external ram usage is within limits of
+ the given value.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---code-size
+\series default
+<Value>
+\begin_inset LatexCommand \index{---code-size<Value>}
+
+\end_inset
+
+ Causes the linker to check if the code usage is within limits of the given
+ value.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---nostdincl
+\begin_inset LatexCommand \index{---nostdincl}
+
+\end_inset
+
+
+\series default
+ This will prevent the compiler from passing on the default include path
+ to the preprocessor.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---nostdlib
+\begin_inset LatexCommand \index{---nostdlib}
+
+\end_inset
+
+
+\series default
+ This will prevent the compiler from passing on the default library path
+ to the linker.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---verbose
+\begin_inset LatexCommand \index{---verbose}
+
+\end_inset
+
+
+\series default
+ Shows the various actions the compiler is performing.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+-V
+\begin_inset LatexCommand \index{-V}
+
+\end_inset
+
+
+\series default
+ Shows the actual commands the compiler is executing.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---no-c-code-in-asm
+\begin_inset LatexCommand \index{---no-c-code-in-asm}
+
+\end_inset
+
+
+\series default
+ Hides your ugly and inefficient c-code from the asm file, so you can always
+ blame the compiler :).
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---i-code-in-asm
+\begin_inset LatexCommand \index{---i-code-in-asm}
+
+\end_inset
+
+
+\series default
+ Include i-codes in the asm file.
+ Sounds like noise but is most helpfull for debugging the compiler itself.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---less-pedantic
+\begin_inset LatexCommand \index{---less-pedantic}
+
+\end_inset
+
+
+\series default
+ Disable some of the more pedantic warnings (jwk burps: please be more specific
+ here, please!)
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---print-search-dirs
+\begin_inset LatexCommand \index{---print-search-dirs}
+
+\end_inset
+
+
+\series default
+ Display the directories in the compiler's search path
+\layout Subsubsection
+
+Intermediate Dump Options
+\begin_inset LatexCommand \index{Options Intermediate Dump}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{Intermediate Dump Options}
+
+\end_inset
+
+
+\layout Standard
+
+The following options are provided for the purpose of retargetting and debugging
+ the compiler.
+ These provided a means to dump the intermediate code (iCode
+\begin_inset LatexCommand \index{iCode}
+
+\end_inset
+
+) generated by the compiler in human readable form at various stages of
+ the compilation process.
+
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---dumpraw
+\begin_inset LatexCommand \index{---dumpraw}
+
+\end_inset
+
+
+\series default
+ This option will cause the compiler to dump the intermediate code into
+ a file of named
+\emph on
+<source filename>.dumpraw
+\emph default
+ just after the intermediate code has been generated for a function, i.e.
+ before any optimizations are done.
+ The basic blocks
+\begin_inset LatexCommand \index{basic blocks}
+
+\end_inset
+
+ at this stage ordered in the depth first number, so they may not be in
+ sequence of execution.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---dumpgcse
+\begin_inset LatexCommand \index{---dumpgcse}
+
+\end_inset
+
+
+\series default
+ Will create a dump of iCode's, after global subexpression elimination
+\begin_inset LatexCommand \index{global subexpression elimination}
+
+\end_inset
+
+, into a file named
+\emph on
+<source filename>.dumpgcse.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---dumpdeadcode
+\begin_inset LatexCommand \index{---dumpdeadcode}
+
+\end_inset
+
+
+\series default
+ Will create a dump of iCode's, after deadcode elimination
+\begin_inset LatexCommand \index{deadcode elimination}
+
+\end_inset
+
+, into a file named
+\emph on
+<source filename>.dumpdeadcode.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---dumploop
+\begin_inset LatexCommand \index{---dumploop}
+
+\end_inset
+
+
+\series default
+\size large
+
+\size default
+Will create a dump of iCode's, after loop optimizations
+\begin_inset LatexCommand \index{loop optimizations}
+
+\end_inset
+
+, into a file named
+\emph on
+<source filename>.dumploop.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---dumprange
+\begin_inset LatexCommand \index{---dumprange}
+
+\end_inset
+
+
+\series default
+\size large
+
+\size default
+Will create a dump of iCode's, after live range analysis
+\begin_inset LatexCommand \index{live range analysis}
+
+\end_inset
+
+, into a file named
+\emph on
+<source filename>.dumprange.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---dumlrange
+\begin_inset LatexCommand \index{---dumlrange}
+
+\end_inset
+
+
+\series default
+ Will dump the life ranges
+\begin_inset LatexCommand \index{life ranges}
+
+\end_inset
+
+ for all symbols.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---dumpregassign
+\begin_inset LatexCommand \index{---dumpregassign}
+
+\end_inset
+
+
+\bar under
+
+\series default
+\bar default
+Will create a dump of iCode's, after register assignment
+\begin_inset LatexCommand \index{register assignment}
+
+\end_inset
+
+, into a file named
+\emph on
+<source filename>.dumprassgn.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---dumplrange
+\begin_inset LatexCommand \index{---dumplrange}
+
+\end_inset
+
+
+\series default
+ Will create a dump of the live ranges of iTemp's
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---dumpall
+\begin_inset LatexCommand \index{---dumpall}
+
+\end_inset
+
+
+\size large
+\bar under
+
+\series default
+\size default
+\bar default
+Will cause all the above mentioned dumps to be created.
+\layout Subsection
+
+Environment variables
+\begin_inset LatexCommand \index{Environment variables}
+
+\end_inset
+
+
+\layout Standard
+
+SDCC recognizes the following environment variables:
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+SDCC_LEAVE_SIGNALS
+\begin_inset LatexCommand \index{SDCC\_LEAVE\_SIGNALS}
+
+\end_inset
+
+
+\series default
+ SDCC installs a signal handler
+\begin_inset LatexCommand \index{ signal handler}
+
+\end_inset
+
+ to be able to delete temporary files after an user break (^C) or an exception.
+ If this environment variable is set, SDCC won't install the signal handler
+ in order to be able to debug SDCC.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+TMP
+\begin_inset LatexCommand \index{TMP}
+
+\end_inset
+
+,\SpecialChar ~
+TEMP
+\begin_inset LatexCommand \index{TEMP}
+
+\end_inset
+
+,\SpecialChar ~
+TMPDIR
+\begin_inset LatexCommand \index{TMPDIR}
+
+\end_inset
+
+
+\series default
+ Path, where temporary files will be created.
+ The order of the variables is the search order.
+ In a standard *nix environment these variables are not set, and there's
+ no need to set them.
+ On Windows it's recommended to set one of them.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+SDCC_HOME
+\begin_inset LatexCommand \index{SDCC\_HOME}
+
+\end_inset
+
+
+\series default
+ Path, see
+\begin_inset Quotes sld
+\end_inset
+
+2.3 Install and search paths
+\begin_inset Quotes srd
+\end_inset
+
+.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+SDCC_INCLUDE
+\begin_inset LatexCommand \index{SDCC\_INCLUDE}
+
+\end_inset
+
+
+\series default
+ Path, see
+\begin_inset Quotes sld
+\end_inset
+
+2.3 Install and search paths
+\begin_inset Quotes srd
+\end_inset
+
+.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+SDCC_LIB
+\begin_inset LatexCommand \index{SDCC\_LIB}
+
+\end_inset
+
+
+\series default
+ Path, see
+\begin_inset Quotes sld
+\end_inset
+
+2.3 Install and search paths
+\begin_inset Quotes srd
+\end_inset
+
+.
+\layout Standard
+
+There are some more environment variables recognized by SDCC, but these
+ are solely used for debugging purposes.
+ They can change or disappear very quickly, and will never be documentated.
+\layout Subsection
+
+MCS51/DS390 Storage Class
+\begin_inset LatexCommand \index{Storage Class}
+
+\end_inset
+
+ Language Extensions
+\layout Standard
+
+In addition to the ANSI storage classes SDCC allows the following MCS51
+ specific storage classes.
+\layout Subsubsection
+
+xdata
+\begin_inset LatexCommand \index{xdata}
+
+\end_inset
+
+
+\layout Standard
+
+Variables declared with this storage class will be placed in the extern
+ RAM.
+ This is the
+\series bold
+default
+\series default
+ storage class for Large Memory model, e.g.:
+\newline
+
+\newline
+
+\family typewriter
+xdata unsigned char xduc;
+\layout Subsubsection
+
+data
+\begin_inset LatexCommand \index{data}
+
+\end_inset
+
+
+\layout Standard
+
+This is the
+\series bold
+default
+\series default
+ storage class for Small Memory model.
+ Variables declared with this storage class will be allocated in the internal
+ RAM, e.g.:
+\newline
+
+\newline
+
+\family typewriter
+data int iramdata;
+\layout Subsubsection
+
+idata
+\begin_inset LatexCommand \index{idata}
+
+\end_inset
+
+
+\layout Standard
+
+Variables declared with this storage class will be allocated into the indirectly
+ addressable portion of the internal ram of a 8051, e.g.:
+\newline
+
+\newline
+
+\family typewriter
+idata int idi;
+\layout Subsubsection
+
+bit
+\begin_inset LatexCommand \index{bit}
+
+\end_inset
+
+
+\layout Standard
+
+This is a data-type and a storage class specifier.
+ When a variable is declared as a bit, it is allocated into the bit addressable
+ memory of 8051, e.g.:
+\newline
+
+\newline
+
+\family typewriter
+bit iFlag;
+\layout Subsubsection
+
+sfr
+\begin_inset LatexCommand \index{sfr}
+
+\end_inset
+
+ / sbit
+\begin_inset LatexCommand \index{sbit}
+
+\end_inset
+
+
+\layout Standard
+
+Like the bit keyword,
+\emph on
+sfr / sbit
+\emph default
+signifies both a data-type and storage class, they are used to describe
+ the special function registers and special bit variables of a 8051, eg:
+\newline
+
+\newline
+
+\family typewriter
+sfr at 0x80 P0; /* special function register P0 at location 0x80 */
+\newline
+sbit at 0xd7 CY; /* CY (Carry Flag
+\begin_inset LatexCommand \index{Carry flag}
+
+\end_inset
+
+) */
+\layout Subsection
+
+Pointers
+\begin_inset LatexCommand \index{Pointers}
+
+\end_inset
+
+
+\layout Standard
+
+SDCC allows (via language extensions) pointers to explicitly point to any
+ of the memory spaces
+\begin_inset LatexCommand \index{memory spaces}
+
+\end_inset
+
+ of the 8051.
+ In addition to the explicit pointers, the compiler uses (by default) generic
+ pointers which can be used to point to any of the memory spaces.
+\newline
+
+\newline
+Pointer declaration examples:
+\newline
+
+\size small
+
+\newline
+
+\family typewriter
+\size default
+/* pointer physically in xternal ram pointing to object in internal ram
+ */
+\newline
+data unsigned char * xdata p;
+\newline
+
+\newline
+/* pointer physically in code rom pointing to data in xdata space */
+\newline
+xdata unsigned char * code p;
+\newline
+
+\newline
+/* pointer physically in code space pointing to data in code space */
+\newline
+code unsigned char * code p;
+\newline
+
+\newline
+/* the folowing is a generic pointer physically located in xdata space */
+\newline
+char * xdata p;
+\family default
+\size small
+
+\newline
+
+\newline
+
+\size default
+Well you get the idea.
+
+\newline
+
+\newline
+All unqualified pointers are treated as 3-byte (4-byte for the ds390)
+\emph on
+generic
+\emph default
+ pointers.
+
+\size small
+
+\newline
+
+\newline
+
+\size default
+The highest order byte of the
+\emph on
+generic
+\emph default
+ pointers contains the data space information.
+ Assembler support routines are called whenever data is stored or retrieved
+ using
+\emph on
+generic
+\emph default
+ pointers.
+ These are useful for developing reusable library routines.
+ Explicitly specifying the pointer type will generate the most efficient
+ code.
+\layout Subsection
+
+Parameters
+\begin_inset LatexCommand \index{Parameters}
+
+\end_inset
+
+ & Local Variables
+\begin_inset LatexCommand \index{Local Variables}
+
+\end_inset
+
+
+\layout Standard
+
+Automatic (local) variables and parameters to functions can either be placed
+ on the stack or in data-space.
+ The default action of the compiler is to place these variables in the internal
+ RAM (for small model) or external RAM (for large model).
+ This in fact makes them
+\emph on
+static
+\begin_inset LatexCommand \index{static}
+
+\end_inset
+
+
+\emph default
+ so by default functions are non-reentrant
+\begin_inset LatexCommand \index{non-reentrant}
+
+\end_inset
+
+.
+\newline
+
+\newline
+They can be placed on the stack
+\begin_inset LatexCommand \index{stack}
+
+\end_inset
+
+ either by using the
+\emph on
+ ---stack-auto
+\begin_inset LatexCommand \index{--stack-auto}
+
+\end_inset
+
+
+\emph default
+ option or by using the
+\emph on
+reentrant
+\begin_inset LatexCommand \index{reentrant}
+
+\end_inset
+
+
+\emph default
+ keyword in the function declaration, e.g.:
+\newline
+
+\size small
+
+\newline
+
+\family typewriter
+\size default
+unsigned char foo(char i) reentrant
+\newline
+{
+\newline
+...
+
+\newline
+}
+\newline
+
+\family default
+
+\newline
+Since stack space on 8051 is limited, the
+\emph on
+reentrant
+\emph default
+keyword or the
+\emph on
+ ---stack-auto
+\emph default
+ option should be used sparingly.
+ Note that the reentrant keyword just means that the parameters & local
+ variables will be allocated to the stack, it
+\emph on
+does not
+\emph default
+ mean that the function is register bank independent.
+\newline
+
+\newline
+Local variables can be assigned storage classes and absolute
+\begin_inset LatexCommand \index{absolute}
+
+\end_inset
+
+ addresses, e.g.:
+\newline
+
+\newline
+
+\family typewriter
+unsigned char foo() {
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+xdata unsigned char i;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+bit bvar;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+data at 0x31 unsiged char j;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+...
+
+\newline
+}
+\newline
+
+\newline
+
+\family default
+In the above example the variable
+\emph on
+i
+\emph default
+ will be allocated in the external ram,
+\emph on
+bvar
+\emph default
+ in bit addressable space and
+\emph on
+ j
+\emph default
+ in internal ram.
+ When compiled with
+\emph on
+---stack-auto
+\emph default
+ or when a function is declared as
+\emph on
+reentrant
+\emph default
+ this should only be done for static variables.
+\layout Standard
+
+Parameters however are not allowed any storage class, (storage classes for
+ parameters will be ignored), their allocation is governed by the memory
+ model in use, and the reentrancy options.
+\layout Subsection
+
+Overlaying
+\begin_inset LatexCommand \index{Overlaying}
+
+\end_inset
+
+
+\layout Standard
+
+For non-reentrant functions SDCC will try to reduce internal ram space usage
+ by overlaying parameters and local variables of a function (if possible).
+ Parameters and local variables of a function will be allocated to an overlayabl
+e segment if the function has
+\emph on
+no other function calls and the function is non-reentrant and the memory
+ model
+\begin_inset LatexCommand \index{memory model}
+
+\end_inset
+
+ is small.
+
+\emph default
+ If an explicit storage class is specified for a local variable, it will
+ NOT be overlayed.
+\layout Standard
+
+Note that the compiler (not the linkage editor) makes the decision for overlayin
+g the data items.
+ Functions that are called from an interrupt service routine should be preceded
+ by a #pragma\SpecialChar ~
+NOOVERLAY
+\begin_inset LatexCommand \index{\#pragma NOOVERLAY}
+
+\end_inset
+
+ if they are not reentrant.
+\layout Standard
+
+Also note that the compiler does not do any processing of inline
+\begin_inset LatexCommand \index{inline}
+
+\end_inset
+
+ assembler code, so the compiler might incorrectly assign local variables
+ and parameters of a function into the overlay segment if the inline assembler
+ code calls other c-functions that might use the overlay.
+ In that case the #pragma\SpecialChar ~
+NOOVERLAY should be used.
+\layout Standard
+
+Parameters and Local variables of functions that contain 16 or 32 bit multiplica
+tion
+\begin_inset LatexCommand \index{multiplication}
+
+\end_inset
+
+ or division
+\begin_inset LatexCommand \index{division}
+
+\end_inset
+
+ will NOT be overlayed since these are implemented using external functions,
+ e.g.:
+\newline
+
+\newline
+
+\family typewriter
+#pragma SAVE
+\newline
+#pragma NOOVERLAY
+\begin_inset LatexCommand \index{\#pragma NOOVERLAY}
+
+\end_inset
+
+
+\newline
+void set_error(unsigned char errcd)
+\newline
+{
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+P3 = errcd;
+\newline
+}
+\newline
+#pragma RESTORE
+\newline
+
+\newline
+void some_isr () interrupt
+\begin_inset LatexCommand \index{interrupt}
+
+\end_inset
+
+ 2 using
+\begin_inset LatexCommand \index{using}
+
+\end_inset
+
+ 1
+\newline
+{
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+...
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+set_error(10);
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+...
+
+\newline
+}
+\newline
+
+\newline
+
+\family default
+In the above example the parameter
+\emph on
+errcd
+\emph default
+ for the function
+\emph on
+set_error
+\emph default
+ would be assigned to the overlayable segment if the #pragma\SpecialChar ~
+NOOVERLAY was
+ not present, this could cause unpredictable runtime behavior when called
+ from an ISR.
+ The #pragma\SpecialChar ~
+NOOVERLAY ensures that the parameters and local variables for
+ the function are NOT overlayed.
+\layout Subsection
+
+Interrupt Service Routines
+\begin_inset LatexCommand \index{Interrupt Service Routines}
+
+\end_inset
+
+
+\layout Standard
+
+SDCC allows interrupt service routines to be coded in C, with some extended
+ keywords.
+\newline
+
+\newline
+
+\family typewriter
+void timer_isr (void) interrupt 2 using 1
+\newline
+{
+\newline
+..
+
+\newline
+}
+\newline
+
+\newline
+
+\family default
+The number following the
+\emph on
+interrupt
+\begin_inset LatexCommand \index{interrupt}
+
+\end_inset
+
+
+\emph default
+ keyword is the interrupt number this routine will service.
+ The compiler will insert a call to this routine in the interrupt vector
+ table for the interrupt number specified.
+ The
+\emph on
+using
+\emph default
+ keyword is used to tell the compiler to use the specified register bank
+ (8051 specific) when generating code for this function.
+ Note that when some function is called from an interrupt service routine
+ it should be preceded by a #pragma\SpecialChar ~
+NOOVERLAY
+\begin_inset LatexCommand \index{\#pragma NOOVERLAY}
+
+\end_inset
+
+ if it is not reentrant.
+ A special note here, int (16 bit) and long (32 bit) integer division, multiplic
+ation & modulus operations are implemented using external support routines
+ developed in ANSI-C, if an interrupt service routine needs to do any of
+ these operations then the support routines (as mentioned in a following
+ section) will have to be recompiled using the
+\emph on
+ ---stack-auto
+\begin_inset LatexCommand \index{---stack-auto}
+
+\end_inset
+
+
+\emph default
+ option and the source file will need to be compiled using the
+\emph on
+---int-long-ren
+\emph default
+t
+\begin_inset LatexCommand \index{---int-long-rent}
+
+\end_inset
+
+ compiler option.
+\layout Standard
+
+If you have multiple source files in your project, interrupt service routines
+ can be present in any of them, but a prototype of the isr MUST be present
+ or included in the file that contains the function
+\emph on
+main
+\emph default
+.
+\layout Standard
+
+Interrupt Numbers and the corresponding address & descriptions for the Standard
+ 8051 are listed below.
+ SDCC will automatically adjust the interrupt vector table
+\begin_inset LatexCommand \index{ interrupt vector table}
+
+\end_inset
+
+ to the maximum interrupt number specified.
+\newline
+
+\layout Standard
+
+
+\begin_inset Tabular
+<lyxtabular version="3" rows="6" columns="3">
+<features>
+<column alignment="center" valignment="top" leftline="true" width="0in">
+<column alignment="center" valignment="top" leftline="true" width="0in">
+<column alignment="center" valignment="top" leftline="true" rightline="true" width="0in">
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+Interrupt #
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+Description
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+Vector Address
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+0
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+External 0
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+0x0003
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+1
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+Timer 0
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+0x000B
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+2
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+External 1
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+0x0013
+\end_inset
+</cell>
+</row>
+<row topline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+3
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+Timer 1
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+0x001B
+\end_inset
+</cell>
+</row>
+<row topline="true" bottomline="true">
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+4
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+Serial
+\end_inset
+</cell>
+<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
+\begin_inset Text
+
+\layout Standard
+
+0x0023
+\end_inset
+</cell>
+</row>
+</lyxtabular>
+
+\end_inset
+
+
+\newline
+
+\newline
+If the interrupt service routine is defined without
+\emph on
+using
+\begin_inset LatexCommand \index{using}
+
+\end_inset
+
+
+\emph default
+ a register bank or with register bank 0 (using 0), the compiler will save
+ the registers used by itself on the stack upon entry and restore them at
+ exit, however if such an interrupt service routine calls another function
+ then the entire register bank will be saved on the stack.
+ This scheme may be advantageous for small interrupt service routines which
+ have low register usage.
+\layout Standard
+
+If the interrupt service routine is defined to be using a specific register
+ bank then only
+\emph on
+a, b & dptr
+\emph default
+ are save and restored, if such an interrupt service routine calls another
+ function (using another register bank) then the entire register bank of
+ the called function will be saved on the stack.
+ This scheme is recommended for larger interrupt service routines.
+\layout Standard
+
+Calling other functions from an interrupt service routine is not recommended,
+ avoid it if possible.
+\newline
+
+\newline
+Also see the _naked modifier.
+\layout Subsection
+
+Critical Functions
+\layout Standard
+
+
+\shape italic
+<TODO: this isn't implemented at all!>
+\shape default
+
+\newline
+
+\newline
+A special keyword may be associated with a function declaring it as
+\emph on
+critical
+\emph default
+.
+ SDCC will generate code to disable all interrupts upon entry to a critical
+ function and enable them back before returning.
+ Note that nesting critical functions may cause unpredictable results.
+\newline
+
+\size small
+
+\newline
+
+\family typewriter
+\size default
+int foo () critical
+\newline
+{
+\newline
+...
+
+\newline
+...
+
+\newline
+}
+\newline
+
+\family default
+
+\newline
+The critical attribute maybe used with other attributes like
+\emph on
+reentrant.
+\layout Subsection
+
+Naked Functions
+\begin_inset LatexCommand \index{Naked Functions}
+
+\end_inset
+
+
+\layout Standard
+
+A special keyword may be associated with a function declaring it as
+\emph on
+_naked
+\begin_inset LatexCommand \index{\_naked}
+
+\end_inset
+
+.
+
+\emph default
+The
+\emph on
+_naked
+\emph default
+ function modifier attribute prevents the compiler from generating prologue
+\begin_inset LatexCommand \index{function prologue}
+
+\end_inset
+
+ and epilogue
+\begin_inset LatexCommand \index{function epilogue}
+
+\end_inset
+
+ code for that function.
+ This means that the user is entirely responsible for such things as saving
+ any registers that may need to be preserved, selecting the proper register
+ bank, generating the
+\emph on
+return
+\emph default
+ instruction at the end, etc.
+ Practically, this means that the contents of the function must be written
+ in inline assembler.
+ This is particularly useful for interrupt functions, which can have a large
+ (and often unnecessary) prologue/epilogue.
+ For example, compare the code generated by these two functions:
+\newline
+
+\newline
+
+\family typewriter
+data unsigned char counter;
+\newline
+void simpleInterrupt(void) interrupt
+\begin_inset LatexCommand \index{interrupt}
+
+\end_inset
+
+ 1
+\newline
+{
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+counter++;
+\newline
+}
+\newline
+
+\newline
+void nakedInterrupt(void) interrupt 2 _naked
+\newline
+{
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+_asm
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+inc\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+_counter
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+reti\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+; MUST explicitly include ret in _naked function.
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+_endasm;
+\newline
+}
+\family default
+
+\newline
+
+\newline
+For an 8051 target, the generated simpleInterrupt looks like:
+\newline
+
+\newline
+
+\family typewriter
+_simpleIterrupt:
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+push\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+acc
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+push\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+b
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+push\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+dpl
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+push\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+dph
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+push\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+psw
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+mov\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+psw,#0x00
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+inc\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+_counter
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+pop\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+psw
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+pop\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+dph
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+pop\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+dpl
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+pop\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+b
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+pop\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+acc
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+reti
+\family default
+
+\newline
+
+\newline
+whereas nakedInterrupt looks like:
+\newline
+
+\newline
+
+\family typewriter
+_nakedInterrupt:
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+inc\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+_counter
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+reti\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+; MUST explicitly include ret(i) in _naked function.
+\family default
+
+\newline
+
+\newline
+While there is nothing preventing you from writing C code inside a _naked
+ function, there are many ways to shoot yourself in the foot doing this,
+ and it is recommended that you stick to inline assembler.
+\layout Subsection
+
+Functions using private banks
+\begin_inset LatexCommand \index{banks}
+
+\end_inset
+
+
+\layout Standard
+
+The
+\emph on
+using
+\begin_inset LatexCommand \index{using}
+
+\end_inset
+
+
+\emph default
+ attribute (which tells the compiler to use a register bank other than the
+ default bank zero) should only be applied to
+\emph on
+interrupt
+\begin_inset LatexCommand \index{interrupt}
+
+\end_inset
+
+
+\emph default
+ functions (see note 1 below).
+ This will in most circumstances make the generated ISR code more efficient
+ since it will not have to save registers on the stack.
+\layout Standard
+
+The
+\emph on
+using
+\emph default
+ attribute will have no effect on the generated code for a
+\emph on
+non-interrupt
+\emph default
+ function (but may occasionally be useful anyway
+\begin_inset Foot
+collapsed true
+
+\layout Standard
+
+possible exception: if a function is called ONLY from 'interrupt' functions
+ using a particular bank, it can be declared with the same 'using' attribute
+ as the calling 'interrupt' functions.
+ For instance, if you have several ISRs using bank one, and all of them
+ call memcpy(), it might make sense to create a specialized version of memcpy()
+ 'using 1', since this would prevent the ISR from having to save bank zero
+ to the stack on entry and switch to bank zero before calling the function
+\end_inset
+
+).
+\newline
+
+\emph on
+(pending: I don't think this has been done yet)
+\layout Standard
+
+An
+\emph on
+interrupt
+\emph default
+ function using a non-zero bank will assume that it can trash that register
+ bank, and will not save it.
+ Since high-priority interrupts
+\begin_inset LatexCommand \index{interrupt priority}
+
+\end_inset
+
+ can interrupt low-priority ones on the 8051 and friends, this means that
+ if a high-priority ISR
+\emph on
+using
+\emph default
+ a particular bank occurs while processing a low-priority ISR
+\emph on
+using
+\emph default
+ the same bank, terrible and bad things can happen.
+ To prevent this, no single register bank should be
+\emph on
+used
+\emph default
+ by both a high priority and a low priority ISR.
+ This is probably most easily done by having all high priority ISRs use
+ one bank and all low priority ISRs use another.
+ If you have an ISR which can change priority at runtime, you're on your
+ own: I suggest using the default bank zero and taking the small performance
+ hit.
+\layout Standard
+
+It is most efficient if your ISR calls no other functions.
+ If your ISR must call other functions, it is most efficient if those functions
+ use the same bank as the ISR (see note 1 below); the next best is if the
+ called functions use bank zero.
+ It is very inefficient to call a function using a different, non-zero bank
+ from an ISR.
+
+\layout Subsection
+
+Absolute Addressing
+\begin_inset LatexCommand \index{Absolute Addressing}
+
+\end_inset
+
+
+\layout Standard
+
+Data items can be assigned an absolute address with the
+\emph on
+at
+\begin_inset LatexCommand \index{at}
+
+\end_inset
+
+ <address>
+\emph default
+ keyword, in addition to a storage class, e.g.:
+\newline
+
+\newline
+
+\family typewriter
+xdata
+\begin_inset LatexCommand \index{xdata}
+
+\end_inset
+
+ at
+\begin_inset LatexCommand \index{at}
+
+\end_inset
+
+ 0x8000 unsigned char PORTA_8255 ;
+\newline
+
+\family default
+
+\newline
+In the above example the PORTA_8255 will be allocated to the location 0x8000
+ of the external ram.
+ Note that this feature is provided to give the programmer access to
+\emph on
+memory mapped
+\emph default
+ devices attached to the controller.
+ The compiler does not actually reserve any space for variables declared
+ in this way (they are implemented with an equate in the assembler).
+ Thus it is left to the programmer to make sure there are no overlaps with
+ other variables that are declared without the absolute address.
+ The assembler listing file (.lst
+\begin_inset LatexCommand \index{.lst}
+
+\end_inset
+
+) and the linker output files (.rst
+\begin_inset LatexCommand \index{.rst}
+
+\end_inset
+
+) and (.map
+\begin_inset LatexCommand \index{.map}
+
+\end_inset
+
+) are a good places to look for such overlaps.
+\newline
+
+\newline
+Absolute address can be specified for variables in all storage classes,
+ e.g.:
+\newline
+
+\newline
+
+\family typewriter
+bit
+\begin_inset LatexCommand \index{bit}
+
+\end_inset
+
+ at
+\begin_inset LatexCommand \index{at}
+
+\end_inset
+
+ 0x02 bvar;
+\newline
+
+\newline
+
+\family default
+The above example will allocate the variable at offset 0x02 in the bit-addressab
+le space.
+ There is no real advantage to assigning absolute addresses to variables
+ in this manner, unless you want strict control over all the variables allocated.
+\layout Subsection
+
+Startup Code
+\begin_inset LatexCommand \index{Startup Code}
+
+\end_inset
+
+
+\layout Standard
+
+The compiler inserts a call to the C routine
+\emph on
+_sdcc_external_startup()
+\begin_inset LatexCommand \index{\_sdcc\_external\_startup()}
+
+\end_inset
+
+
+\series bold
+\emph default
+
+\series default
+at the start of the CODE area.
+ This routine is in the runtime library.
+ By default this routine returns 0, if this routine returns a non-zero value,
+ the static & global variable initialization will be skipped and the function
+ main will be invoked Other wise static & global variables will be initialized
+ before the function main is invoked.
+ You could add a
+\emph on
+_sdcc_external_startup()
+\emph default
+ routine to your program to override the default if you need to setup hardware
+ or perform some other critical operation prior to static & global variable
+ initialization.
+\layout Subsection
+
+Inline Assembler Code
+\begin_inset LatexCommand \index{Inline Assembler Code}
+
+\end_inset
+
+
+\layout Standard
+
+SDCC allows the use of in-line assembler with a few restriction as regards
+ labels.
+ All labels defined within inline assembler code
+\emph on
+has to be
+\emph default
+ of the form
+\emph on
+nnnnn$
+\emph default
+ where nnnn is a number less than 100 (which implies a limit of utmost 100
+ inline assembler labels
+\emph on
+per function
+\emph default
+\noun on
+)
+\noun default
+.
+ It is strongly recommended that each assembly instruction (including labels)
+ be placed in a separate line (as the example shows).
+ When the
+\emph on
+---peep-asm
+\begin_inset LatexCommand \index{--peep-asm}
+
+\end_inset
+
+
+\emph default
+ command line option is used, the inline assembler code will be passed through
+ the peephole optimizer
+\begin_inset LatexCommand \index{Peephole optimizer}
+
+\end_inset
+
+.
+ This might cause some unexpected changes in the inline assembler code.
+ Please go throught the peephole optimizer rules defined in file
+\emph on
+SDCCpeeph.def
+\emph default
+ carefully before using this option.
+\newline
+
+\newline
+
+\family typewriter
+_asm
+\begin_inset LatexCommand \index{\_asm}
+
+\end_inset
+
+
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+mov\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+b,#10
+\newline
+00001$:
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+djnz\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+b,00001$
+\newline
+_endasm
+\begin_inset LatexCommand \index{\_endasm}
+
+\end_inset
+
+ ;
+\family default
+\size small
+
+\newline
+
+\newline
+
+\size default
+The inline assembler code can contain any valid code understood by the assembler
+, this includes any assembler directives and comment lines.
+ The compiler does not do any validation of the code within the
+\family typewriter
+_asm ...
+ _endasm;
+\family default
+ keyword pair.
+
+\newline
+
+\newline
+Inline assembler code cannot reference any C-Labels, however it can reference
+ labels
+\begin_inset LatexCommand \index{Labels}
+
+\end_inset
+
+ defined by the inline assembler, e.g.:
+\newline
+
+\newline
+
+\family typewriter
+foo() {
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+/* some c code */
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+_asm
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+; some assembler code
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+ljmp $0003
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+_endasm;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+/* some more c code */
+\newline
+clabel:\SpecialChar ~
+\SpecialChar ~
+/* inline assembler cannot reference this label */
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+_asm
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+$0003: ;label (can be reference by inline assembler only)
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+_endasm ;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+/* some more c code */
+\newline
+}
+\newline
+
+\newline
+
+\family default
+In other words inline assembly code can access labels defined in inline
+ assembly within the scope of the funtion.
+
+\layout Standard
+
+The same goes the other way, ie.
+ labels defines in inline assembly CANNOT be accessed by C statements.
+\layout Subsection
+
+int (16 bit)
+\begin_inset LatexCommand \index{int (16 bit)}
+
+\end_inset
+
+ and long (32 bit)
+\begin_inset LatexCommand \index{long (32 bit)}
+
+\end_inset
+
+ Support
+\layout Standard
+
+For signed & unsigned int (16 bit) and long (32 bit) variables, division,
+ multiplication and modulus operations are implemented by support routines.
+ These support routines are all developed in ANSI-C to facilitate porting
+ to other MCUs, although some model specific assembler optimations are used.
+ The following files contain the described routine, all of them can be found
+ in <installdir>/share/sdcc/lib.
+\newline
+
+\newline
+
+\emph on
+<pending: tabularise this>
+\emph default
+
+\newline
+
+\newline
+_mulsint.c - signed 16 bit multiplication (calls _muluint)
+\newline
+_muluint.c - unsigned 16 bit multiplication
+\newline
+_divsint.c - signed 16 bit division (calls _divuint)
+\newline
+_divuint.c - unsigned 16 bit division
+\newline
+_modsint.c - signed 16 bit modulus (call _moduint)
+\newline
+_moduint.c - unsigned 16 bit modulus
+\newline
+_mulslong.c - signed 32 bit multiplication (calls _mululong)
+\newline
+_mululong.c - unsigned32 bit multiplication
+\newline
+_divslong.c - signed 32 division (calls _divulong)
+\newline
+_divulong.c - unsigned 32 division
+\newline
+_modslong.c - signed 32 bit modulus (calls _modulong)
+\newline
+_modulong.c - unsigned 32 bit modulus
+\size footnotesize
+
+\newline
+
+\newline
+
+\size default
+Since they are compiled as
+\emph on
+non-reentrant
+\emph default
+
+\begin_inset LatexCommand \index{reentrant}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{non-reentrant}
+
+\end_inset
+
+, interrupt
+\begin_inset LatexCommand \index{interrupt}
+
+\end_inset
+
+ service routines should not do any of the above operations.
+ If this is unavoidable then the above routines will need to be compiled
+ with the
+\emph on
+---stack-auto
+\begin_inset LatexCommand \index{---stack-auto}
+
+\end_inset
+
+
+\emph default
+ option, after which the source program will have to be compiled with
+\emph on
+---int-long-rent
+\begin_inset LatexCommand \index{---int-long-rent}
+
+\end_inset
+
+
+\emph default
+ option.
+\layout Subsection
+
+Floating Point Support
+\begin_inset LatexCommand \index{Floating Point Support}
+
+\end_inset
+
+
+\layout Standard
+
+SDCC supports IEEE (single precision 4bytes) floating point numbers.The floating
+ point support routines are derived from gcc's floatlib.c and consists of
+ the following routines:
+\newline
+
+\newline
+
+\emph on
+<pending: tabularise this>
+\emph default
+
+\newline
+
+\newline
+_fsadd.c - add floating point numbers
+\newline
+_fssub.c - subtract floating point numbers
+\newline
+_fsdiv.c - divide floating point numbers
+\newline
+_fsmul.c - multiply floating point numbers
+\newline
+_fs2uchar.c - convert floating point to unsigned char
+\newline
+_fs2char.c - convert floating point to signed char
+\newline
+_fs2uint.c - convert floating point to unsigned int
+\newline
+_fs2int.c - convert floating point to signed int
+\newline
+_fs2ulong.c - convert floating point to unsigned long
+\newline
+_fs2long.c - convert floating point to signed long
+\newline
+_uchar2fs.c - convert unsigned char to floating point
+\newline
+_char2fs.c - convert char to floating point number
+\newline
+_uint2fs.c - convert unsigned int to floating point
+\newline
+_int2fs.c - convert int to floating point numbers
+\newline
+_ulong2fs.c - convert unsigned long to floating point number
+\newline
+_long2fs.c - convert long to floating point number
+\size footnotesize
+
+\newline
+
+\newline
+
+\size default
+Note if all these routines are used simultaneously the data space might
+ overflow.
+ For serious floating point usage it is strongly recommended that the large
+ model be used.
+\layout Subsection
+
+MCS51 Memory Models
+\begin_inset LatexCommand \index{Memory Models}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{MCS51 Memory Models}
+
+\end_inset
+
+
+\layout Standard
+
+SDCC allows two memory models for MCS51 code, small and large.
+ Modules compiled with different memory models should
+\emph on
+never
+\emph default
+ be combined together or the results would be unpredictable.
+ The library routines supplied with the compiler are compiled as both small
+ and large.
+ The compiled library modules are contained in seperate directories as small
+ and large so that you can link to either set.
+
+\layout Standard
+
+When the large model is used all variables declared without a storage class
+ will be allocated into the external ram, this includes all parameters and
+ local variables (for non-reentrant functions).
+ When the small model is used variables without storage class are allocated
+ in the internal ram.
+\layout Standard
+
+Judicious usage of the processor specific storage classes
+\begin_inset LatexCommand \index{storage classes}
+
+\end_inset
+
+ and the 'reentrant' function type will yield much more efficient code,
+ than using the large model.
+ Several optimizations are disabled when the program is compiled using the
+ large model, it is therefore strongly recommdended that the small model
+ be used unless absolutely required.
+\layout Subsection
+
+DS390 Memory Models
+\begin_inset LatexCommand \index{Memory Models}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{DS390 Memory Models}
+
+\end_inset
+
+
+\layout Standard
+
+The only model supported is Flat 24
+\begin_inset LatexCommand \index{Flat 24}
+
+\end_inset
+
+.
+ This generates code for the 24 bit contiguous addressing mode of the Dallas
+ DS80C390 part.
+ In this mode, up to four meg of external RAM or code space can be directly
+ addressed.
+ See the data sheets at www.dalsemi.com for further information on this part.
+\newline
+
+\newline
+In older versions of the compiler, this option was used with the MCS51 code
+ generator (
+\emph on
+-mmcs51
+\emph default
+).
+ Now, however, the '390 has it's own code generator, selected by the
+\emph on
+-mds390
+\emph default
+ switch.
+
+\newline
+
+\newline
+Note that the compiler does not generate any code to place the processor
+ into 24 bitmode (although
+\emph on
+tinibios
+\emph default
+ in the ds390 libraries will do that for you).
+ If you don't use
+\emph on
+tinibios
+\emph default
+
+\begin_inset LatexCommand \index{tinibios}
+
+\end_inset
+
+, the boot loader or similar code must ensure that the processor is in 24
+ bit contiguous addressing mode before calling the SDCC startup code.
+\newline
+
+\newline
+Like the
+\emph on
+---model-large
+\emph default
+ option, variables will by default be placed into the XDATA segment.
+
+\newline
+
+\newline
+Segments may be placed anywhere in the 4 meg address space using the usual
+ ---*-loc options.
+ Note that if any segments are located above 64K, the -r flag must be passed
+ to the linker to generate the proper segment relocations, and the Intel
+ HEX output format must be used.
+ The -r flag can be passed to the linker by using the option
+\emph on
+-Wl-r
+\emph default
+ on the sdcc command line.
+ However, currently the linker can not handle code segments > 64k.
+\layout Subsection
+
+Defines Created by the Compiler
+\begin_inset LatexCommand \index{Defines Created by the Compiler}
+
+\end_inset
+
+
+\layout Standard
+
+The compiler creates the following #defines
+\begin_inset LatexCommand \index{\#defines}
+
+\end_inset
+
+.
+\layout Itemize
+
+SDCC
+\begin_inset LatexCommand \index{SDCC}
+
+\end_inset
+
+ - this Symbol is always defined.
+\layout Itemize
+
+SDCC_mcs51
+\begin_inset LatexCommand \index{SDCC\_mcs51}
+
+\end_inset
+
+ or SDCC_ds390
+\begin_inset LatexCommand \index{SDCC\_ds390}
+
+\end_inset
+
+ or SDCC_z80
+\begin_inset LatexCommand \index{SDCC\_z80}
+
+\end_inset
+
+, etc - depending on the model used (e.g.: -mds390)
+\layout Itemize
+
+__mcs51
+\begin_inset LatexCommand \index{\_\_mcs51}
+
+\end_inset
+
+ or __ds390
+\begin_inset LatexCommand \index{\_\_ds390}
+
+\end_inset
+
+ or __z80
+\begin_inset LatexCommand \index{\_\_z80}
+
+\end_inset
+
+, etc - depending on the model used (e.g.
+ -mz80)
+\layout Itemize
+
+SDCC_STACK_AUTO
+\begin_inset LatexCommand \index{SDCC\_STACK\_AUTO}
+
+\end_inset
+
+ - this symbol is defined when
+\emph on
+---stack-auto
+\emph default
+ option is used.
+\layout Itemize
+
+SDCC_MODEL_SMALL
+\begin_inset LatexCommand \index{SDCC\_MODEL\_SMALL}
+
+\end_inset
+
+ - when
+\emph on
+---model-small
+\emph default
+ is used.
+\layout Itemize
+
+SDCC_MODEL_LARGE
+\begin_inset LatexCommand \index{SDCC\_MODEL\_LARGE}
+
+\end_inset
+
+ - when
+\emph on
+---model-large
+\emph default
+ is used.
+\layout Itemize
+
+SDCC_USE_XSTACK
+\begin_inset LatexCommand \index{SDCC\_USE\_XSTACK}
+
+\end_inset
+
+ - when
+\emph on
+---xstack
+\emph default
+ option is used.
+\layout Itemize
+
+SDCC_STACK_TENBIT
+\begin_inset LatexCommand \index{SDCC\_STACK\_TENBIT}
+
+\end_inset
+
+ - when
+\emph on
+-mds390
+\emph default
+ is used
+\layout Itemize
+
+SDCC_MODEL_FLAT24
+\begin_inset LatexCommand \index{SDCC\_MODEL\_FLAT24}
+
+\end_inset
+
+ - when
+\emph on
+-mds390
+\emph default
+ is used
+\layout Section
+
+SDCC Technical Data
+\layout Subsection
+
+Optimizations
+\begin_inset LatexCommand \index{Optimizations}
+
+\end_inset
+
+
+\layout Standard
+
+SDCC performs a host of standard optimizations in addition to some MCU specific
+ optimizations.
+
+\layout Subsubsection
+
+Sub-expression Elimination
+\begin_inset LatexCommand \index{Sub-expression Elimination}
+
+\end_inset
+
+
+\layout Standard
+
+The compiler does local and global common subexpression elimination, e.g.:
+
+\newline
+
+\newline
+
+\family typewriter
+i = x + y + 1;
+\newline
+j = x + y;
+\family default
+
+\newline
+
+\newline
+will be translated to
+\newline
+
+\newline
+
+\family typewriter
+iTemp = x + y
+\newline
+i = iTemp + 1
+\newline
+j = iTemp
+\newline
+
+\family default
+
+\newline
+Some subexpressions are not as obvious as the above example, e.g.:
+\newline
+
+\newline
+
+\family typewriter
+a->b[i].c = 10;
+\newline
+a->b[i].d = 11;
+\family default
+
+\newline
+
+\newline
+In this case the address arithmetic a->b[i] will be computed only once;
+ the equivalent code in C would be.
+\newline
+
+\newline
+
+\family typewriter
+iTemp = a->b[i];
+\newline
+iTemp.c = 10;
+\newline
+iTemp.d = 11;
+\family default
+
+\newline
+
+\newline
+The compiler will try to keep these temporary variables in registers.
+\layout Subsubsection
+
+Dead-Code Elimination
+\begin_inset LatexCommand \index{Dead-Code Elimination}
+
+\end_inset
+
+
+\layout Standard
+
+
+\family typewriter
+int global;
+\newline
+void f () {
+\newline
+\SpecialChar ~
+\SpecialChar ~
+int i;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+i = 1; \SpecialChar ~
+/* dead store */
+\newline
+\SpecialChar ~
+\SpecialChar ~
+global = 1;\SpecialChar ~
+/* dead store */
+\newline
+\SpecialChar ~
+\SpecialChar ~
+global = 2;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+return;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+global = 3;\SpecialChar ~
+/* unreachable */
+\newline
+}
+\family default
+
+\newline
+
+\newline
+will be changed to
+\newline
+
+\newline
+
+\family typewriter
+int global; void f ()
+\newline
+{
+\newline
+\SpecialChar ~
+\SpecialChar ~
+global = 2;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+return;
+\newline
+}
+\layout Subsubsection
+
+Copy-Propagation
+\begin_inset LatexCommand \index{Copy-Propagation}
+
+\end_inset
+
+
+\layout Standard
+
+
+\family typewriter
+int f() {
+\newline
+\SpecialChar ~
\SpecialChar ~
+int i, j;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+i = 10;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+j = i;
+\newline
+\SpecialChar ~
+\SpecialChar ~
+return j;
+\newline
+}
+\family default
+
+\newline
+
+\newline
+will be changed to
+\newline
+
+\newline
+
+\family typewriter
+int f() {
+\newline
\SpecialChar ~
+ \SpecialChar ~
+ int i,j;
+\newline
\SpecialChar ~
+ \SpecialChar ~
+ i = 10;
+\newline
\SpecialChar ~
+ \SpecialChar ~
+ j = 10;
+\newline
\SpecialChar ~
+ \SpecialChar ~
+ return 10;
+\newline
+}
+\newline
+
+\newline
+
+\family default
+Note: the dead stores created by this copy propagation will be eliminated
+ by dead-code elimination.
+\layout Subsubsection
+
+Loop Optimizations
+\begin_inset LatexCommand \index{Loop Optimizations}
+
+\end_inset
+
+
+\layout Standard
+
+Two types of loop optimizations are done by SDCC loop invariant lifting
+ and strength reduction of loop induction variables.
+ In addition to the strength reduction the optimizer marks the induction
+ variables and the register allocator tries to keep the induction variables
+ in registers for the duration of the loop.
+ Because of this preference of the register allocator
+\begin_inset LatexCommand \index{Register allocator}
+
+\end_inset
+
+, loop induction optimization causes an increase in register pressure, which
+ may cause unwanted spilling of other temporary variables into the stack
+\begin_inset LatexCommand \index{stack}
+
+\end_inset
+
+ / data space.
+ The compiler will generate a warning message when it is forced to allocate
+ extra space either on the stack or data space.
+ If this extra space allocation is undesirable then induction optimization
+ can be eliminated either for the entire source file (with ---noinduction
+ option) or for a given function only using #pragma\SpecialChar ~
+NOINDUCTION
+\begin_inset LatexCommand \index{\#pragma NOINDUCTION}
+
+\end_inset
+
+.
+\newline
+
+\newline
+Loop Invariant:
+\newline
+
+\newline
+
+\family typewriter
+for (i = 0 ; i < 100 ; i ++)
+\newline
+ \SpecialChar ~
+ \SpecialChar ~
+f += k + l;
+\family default
+
+\newline
+
+\newline
+changed to
+\newline
+
+\newline
+
+\family typewriter
+itemp = k + l;
+\newline
+for (i = 0; i < 100; i++)
+\newline
\SpecialChar ~
\SpecialChar ~
+f += itemp;
+\family default
+
+\newline
+
+\newline
+As mentioned previously some loop invariants are not as apparent, all static
+ address computations are also moved out of the loop.
+\newline
+
+\newline
+Strength Reduction
+\begin_inset LatexCommand \index{Strength Reduction}
+
+\end_inset
+
+, this optimization substitutes an expression by a cheaper expression:
+\newline
+
+\newline
+
+\family typewriter
+for (i=0;i < 100; i++)
+\newline
\SpecialChar ~
\SpecialChar ~
-\SpecialChar ~
- flags: -\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
+ar[i*5] = i*3;
+\family default
+
+\newline
+
+\newline
+changed to
+\newline
+
+\newline
+
+\family typewriter
+itemp1 = 0;
+\newline
+itemp2 = 0;
+\newline
+for (i=0;i< 100;i++) {
+\newline
+ \SpecialChar ~
+ \SpecialChar ~
+ar[itemp1] = itemp2;
+\newline
+ \SpecialChar ~
+ \SpecialChar ~
+itemp1 += 5;
+\newline
+ \SpecialChar ~
+ \SpecialChar ~
+itemp2 += 3;
+\newline
+}
+\family default
+
+\newline
+
+\newline
+The more expensive multiplication
+\begin_inset LatexCommand \index{multiplication}
+
+\end_inset
+
+ is changed to a less expensive addition.
+\layout Subsubsection
+
+Loop Reversing
+\begin_inset LatexCommand \index{Loop Reversing}
+
+\end_inset
+
+
+\layout Standard
+
+This optimization is done to reduce the overhead of checking loop boundaries
+ for every iteration.
+ Some simple loops can be reversed and implemented using a
+\begin_inset Quotes eld
+\end_inset
+
+decrement and jump if not zero
+\begin_inset Quotes erd
+\end_inset
+
+ instruction.
+ SDCC checks for the following criterion to determine if a loop is reversible
+ (note: more sophisticated compilers use data-dependency analysis to make
+ this determination, SDCC uses a more simple minded analysis).
+\layout Itemize
+
+The 'for' loop is of the form
+\newline
+
+\newline
+
+\family typewriter
+for (<symbol> = <expression> ; <sym> [< | <=] <expression> ; [<sym>++ |
+ <sym> += 1])
+\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- left justify output in specified field width
+<for body>
+\layout Itemize
+
+The <for body> does not contain
+\begin_inset Quotes eld
+\end_inset
+
+continue
+\begin_inset Quotes erd
+\end_inset
+
+ or 'break
+\begin_inset Quotes erd
+\end_inset
+
+.
+\layout Itemize
+
+All goto's are contained within the loop.
+\layout Itemize
+
+No function calls within the loop.
+\layout Itemize
+
+The loop control variable <sym> is not assigned any value within the loop
+\layout Itemize
+
+The loop control variable does NOT participate in any arithmetic operation
+ within the loop.
+\layout Itemize
+
+There are NO switch statements in the loop.
+\layout Subsubsection
+
+Algebraic Simplifications
+\layout Standard
+
+SDCC does numerous algebraic simplifications, the following is a small sub-set
+ of these optimizations.
+\newline
+
+\newline
+
+\family typewriter
+i = j + 0 ; /* changed to */ i = j;
+\newline
+i /= 2; /* changed to */ i >>= 1;
+\newline
+i = j - j ; /* changed to */ i = 0;
+\newline
+i = j / 1 ; /* changed to */ i = j;
+\family default
+
+\newline
+
+\newline
+Note the subexpressions
+\begin_inset LatexCommand \index{subexpressions}
+
+\end_inset
+
+ given above are generally introduced by macro expansions or as a result
+ of copy/constant propagation.
+\layout Subsubsection
+
+'switch' Statements
+\begin_inset LatexCommand \index{switch Statements}
+
+\end_inset
+
+
+\layout Standard
+
+SDCC changes switch statements to jump tables
+\begin_inset LatexCommand \index{jump tables}
+
+\end_inset
+
+ when the following conditions are true.
+
+\layout Itemize
+
+The case labels are in numerical sequence, the labels need not be in order,
+ and the starting number need not be one or zero.
+\newline
+
+\newline
+
+\family typewriter
+switch(i) {\SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+switch (i) {
+\newline
+case 4:...
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+case 1: ...
+
+\newline
+case 5:...
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+case 2: ...
+
+\newline
+case 3:...
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+case 3: ...
+
+\newline
+case 6:...
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+case 4: ...
+
+\newline
+}\SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+}
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- +\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- prefix output with +/- sign if output is signed type
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- space\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- prefix output with a blank if it's a signed positive value
+
+\family default
+Both the above switch statements will be implemented using a jump-table.
+\layout Itemize
+
+The number of case labels is at least three, since it takes two conditional
+ statements to handle the boundary conditions.
+\layout Itemize
+
+The number of case labels is less than 84, since each label takes 3 bytes
+ and a jump-table can be utmost 256 bytes long.
+
+\layout Standard
+
+Switch statements which have gaps in the numeric sequence or those that
+ have more that 84 case labels can be split into more than one switch statement
+ for efficient code generation, e.g.:
+\newline
+
+\newline
+
+\family typewriter
+switch (i) {
+\newline
+case 1: ...
+
+\newline
+case 2: ...
+
+\newline
+case 3: ...
+
+\newline
+case 4: ...
+
+\newline
+case 9: ...
+
+\newline
+case 10: ...
+
+\newline
+case 11: ...
+
+\newline
+case 12: ...
+
+\newline
+}
+\family default
+
+\newline
+
+\newline
+If the above switch statement is broken down into two switch statements
+\newline
+
+\newline
+
+\family typewriter
+switch (i) {
+\newline
+case 1: ...
+
+\newline
+case 2: ...
+
+\newline
+case 3: ...
+
+\newline
+case 4: ...
+
+\newline
+}
+\newline
+
+\newline
+
+\family default
+and
+\family typewriter
+
+\newline
+
+\newline
+switch (i) {
+\newline
+case 9: \SpecialChar ~
+...
+
+\newline
+case 10: ...
+
+\newline
+case 11: ...
+
+\newline
+case 12:\SpecialChar ~
+...
+
+\newline
+}
+\newline
+
+\newline
+
+\family default
+then both the switch statements will be implemented using jump-tables whereas
+ the unmodified switch statement will not be.
+\layout Subsubsection
+
+Bit-shifting Operations
+\begin_inset LatexCommand \index{Bit-shifting Operations}
+
+\end_inset
+
+.
+\layout Standard
+
+Bit shifting is one of the most frequently used operation in embedded programmin
+g.
+ SDCC tries to implement bit-shift operations in the most efficient way
+ possible, e.g.:
+\newline
+
+\family typewriter
+
+\newline
+unsigned char i;
+\newline
+...
+
+\newline
+i>>= 4;
+\newline
+...
+\newline
+
+\family default
+
+\newline
+generates the following code:
+\newline
+
+\family typewriter
+
+\newline
+mov a,_i
+\newline
+swap a
+\newline
+anl a,#0x0f
+\newline
+mov _i,a
+\family default
+
+\newline
+
+\newline
+In general SDCC will never setup a loop if the shift count is known.
+ Another example:
+\newline
+
+\newline
+
+\family typewriter
+unsigned int i;
+\newline
+...
+
+\newline
+i >>= 9;
+\newline
+...
+\family default
+
+\newline
+
+\newline
+will generate:
+\newline
+
+\newline
+
+\family typewriter
+mov a,(_i + 1)
+\newline
+mov (_i + 1),#0x00
+\newline
+clr c
+\newline
+rrc a
+\newline
+mov _i,a
+\family default
+
+\newline
+
+\newline
+Note that SDCC stores numbers in little-endian format (i.e.
+ lowest order first).
+\layout Subsubsection
+
+Bit-rotation
+\begin_inset LatexCommand \index{Bit-rotation}
+
+\end_inset
+
+
+\layout Standard
+
+A special case of the bit-shift operation is bit rotation, SDCC recognizes
+ the following expression to be a left bit-rotation:
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- width:\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- specifies minimum number of characters outputted for numbers
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- or strings.
-
+
+\family typewriter
+unsigned char i;
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- - For numbers, spaces are added on the left when needed.
+...
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- If width starts with a zero character, zeroes and used
+i = ((i << 1) | (i >> 7));
+\family default
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- instead of spaces.
-
+...
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- - For strings, spaces are are added on the left or right (when
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- flag '-' is used) when needed.
-
+will generate the following code:
+\newline
+
+\newline
+
+\family typewriter
+mov a,_i
+\newline
+rl a
+\newline
+mov _i,a
+\family default
+
+\newline
+
+\newline
+SDCC uses pattern matching on the parse tree to determine this operation.Variatio
+ns of this case will also be recognized as bit-rotation, i.e.:
+\newline
+
+\newline
+
+\family typewriter
+i = ((i >> 7) | (i << 1)); /* left-bit rotation */
+\layout Subsubsection
+
+Highest Order Bit
+\begin_inset LatexCommand \index{Highest Order Bit}
+
+\end_inset
+
+
+\layout Standard
+
+It is frequently required to obtain the highest order bit of an integral
+ type (long, int, short or char types).
+ SDCC recognizes the following expression to yield the highest order bit
+ and generates optimized code for it, e.g.:
+\newline
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
+\family typewriter
+unsigned int gint;
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- b/B:\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- byte argument (used by d, u, o, x, X)
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- l/L:\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- long argument (used by d, u, o, x, X)
+foo () {
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- type:\SpecialChar ~
- d\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- decimal number
+unsigned char hob;
\newline
\SpecialChar ~
\SpecialChar ~
+...
+
+\newline
\SpecialChar ~
\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- u\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- unsigned decimal number
+hob = (gint >> 15) & 1;
\newline
\SpecialChar ~
\SpecialChar ~
+..
+
+\newline
+}
+\family default
+
+\newline
+
+\newline
+will generate the following code:
+\newline
+
+\family typewriter
+
+\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-\SpecialChar ~
- o\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- unsigned octal number
-\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ 61 ;\SpecialChar ~
+ hob.c 7
+\newline
\SpecialChar ~
\SpecialChar ~
+ 000A E5*01\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- x\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- unsigned hexadecimal number (0-9, a-f)
-\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ 62\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ mov\SpecialChar ~
+ a,(_gint + 1)
+\newline
\SpecialChar ~
\SpecialChar ~
+ 000C 33\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- X\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- unsigned hexadecimal number (0-9, A-F)
-\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ 63\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ rlc\SpecialChar ~
+ a
+\newline
\SpecialChar ~
\SpecialChar ~
- c\SpecialChar ~
+ 000D E4\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- character
-\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ 64\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- s\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ clr\SpecialChar ~
+ a
+\newline
\SpecialChar ~
\SpecialChar ~
+ 000E 13\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- string (generic pointer)
-\newline
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ 65\SpecialChar ~
\SpecialChar ~
- p\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- generic pointer (I:data/idata, C:code, X:xdata, P:paged)
+ rrc\SpecialChar ~
+ a
\newline
\SpecialChar ~
+\SpecialChar ~
+ 000F F5*02\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ 66\SpecialChar ~
\SpecialChar ~
- f\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- float (still to be implemented)
-\layout Standard
+ mov\SpecialChar ~
+ _foo_hob_1_1,a
+\newline
-Also contains a very simple version of printf (printf_small).
- This simplified version of printf supports only the following formats.
-\layout Standard
+\newline
-format\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-output\SpecialChar ~
-type\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-argument-type
+\family default
+Variations of this case however will
+\emph on
+not
+\emph default
+ be recognized.
+ It is a standard C expression, so I heartily recommend this be the only
+ way to get the highest order bit, (it is portable).
+ Of course it will be recognized even if it is embedded in other expressions,
+ e.g.:
\newline
-%d \SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-decimal \SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- short/int
+
\newline
-%ld\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-decimal\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-long
+
+\family typewriter
+xyz = gint + ((gint >> 15) & 1);
+\family default
+
\newline
-%hd\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-decimal\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-char
+
\newline
-%x\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-hexadecimal\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-short/int
+will still be recognized.
+\layout Subsubsection
+
+Peephole Optimizer
+\begin_inset LatexCommand \index{Peephole optimizer}
+
+\end_inset
+
+
+\layout Standard
+
+The compiler uses a rule based, pattern matching and re-writing mechanism
+ for peep-hole optimization.
+ It is inspired by
+\emph on
+copt
+\emph default
+ a peep-hole optimizer by Christopher W.
+ Fraser (cwfraser@microsoft.com).
+ A default set of rules are compiled into the compiler, additional rules
+ may be added with the
+\emph on
+---peep-file
+\begin_inset LatexCommand \index{---peep-file}
+
+\end_inset
+
+ <filename>
+\emph default
+ option.
+ The rule language is best illustrated with examples.
\newline
-%lx\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-hexadecimal\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-long
+
\newline
-%hx\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-hexadecimal\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-char
+
+\family typewriter
+replace {
\newline
-%o\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-octal\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-short/int
+mov %1,a
\newline
-%lo\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-octal\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+mov a,%1
+\newline
+} by {
+\newline
\SpecialChar ~
\SpecialChar ~
-long
+mov %1,a
+\newline
+}
+\family default
+
+\newline
+
+\newline
+The above rule will change the following assembly sequence:
+\newline
+
\newline
-%ho\SpecialChar ~
+
+\family typewriter
\SpecialChar ~
\SpecialChar ~
+mov r1,a
+\newline
\SpecialChar ~
\SpecialChar ~
+mov a,r1
+\family default
+
+\newline
+
+\newline
+to
+\newline
+
+\newline
+
+\family typewriter
+mov r1,a
+\family default
+
+\newline
+
+\newline
+Note: All occurrences of a
+\emph on
+%n
+\emph default
+ (pattern variable) must denote the same string.
+ With the above rule, the assembly sequence:
+\newline
+
+\newline
+
+\family typewriter
\SpecialChar ~
\SpecialChar ~
+mov r1,a
+\newline
\SpecialChar ~
-octal\SpecialChar ~
\SpecialChar ~
+mov a,r2
+\family default
+
+\newline
+
+\newline
+will remain unmodified.
+\newline
+
+\newline
+Other special case optimizations may be added by the user (via
+\emph on
+---peep-file option
+\emph default
+).
+ E.g.
+ some variants of the 8051 MCU allow only
+\family typewriter
+ajmp
+\family default
+ and
+\family typewriter
+acall
+\family default
+.
+ The following two rules will change all
+\family typewriter
+ljmp
+\family default
+ and
+\family typewriter
+lcall
+\family default
+ to
+\family typewriter
+ajmp
+\family default
+ and
+\family typewriter
+acall
+\family default
+
+\newline
+
+\newline
+
+\family typewriter
+replace { lcall %1 } by { acall %1 }
+\newline
+replace { ljmp %1 } by { ajmp %1 }
+\family default
+
+\newline
+
+\newline
+The
+\emph on
+inline-assembler code
+\emph default
+ is also passed through the peep hole optimizer, thus the peephole optimizer
+ can also be used as an assembly level macro expander.
+ The rules themselves are MCU dependent whereas the rule language infra-structur
+e is MCU independent.
+ Peephole optimization rules for other MCU can be easily programmed using
+ the rule language.
+\newline
+
+\newline
+The syntax for a rule is as follows:
+\newline
+
+\newline
+
+\family typewriter
+rule := replace [ restart ] '{' <assembly sequence> '
+\backslash
+n'
+\newline
\SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ '}' by '{' '
+\backslash
+n'
+\newline
\SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ <assembly sequence> '
+\backslash
+n'
+\newline
\SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ '}' [if <functionName> ] '
+\backslash
+n'
+\newline
+
+\family default
+
+\newline
+<assembly sequence> := assembly instruction (each instruction including
+ labels must be on a separate line).
+\newline
+
+\newline
+The optimizer will apply to the rules one by one from the top in the sequence
+ of their appearance, it will terminate when all rules are exhausted.
+ If the 'restart' option is specified, then the optimizer will start matching
+ the rules again from the top, this option for a rule is expensive (performance)
+, it is intended to be used in situations where a transformation will trigger
+ the same rule again.
+ An example of this (not a good one, it has side effects) is the following
+ rule:
+\newline
+
+\newline
+
+\family typewriter
+replace restart {
+\newline
\SpecialChar ~
\SpecialChar ~
+pop %1
+\newline
\SpecialChar ~
\SpecialChar ~
-char
+push %1 } by {
\newline
-%c\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+; nop
+\newline
+}
+\family default
+
+\newline
+
+\newline
+Note that the replace pattern cannot be a blank, but can be a comment line.
+ Without the 'restart' option only the inner most 'pop' 'push' pair would
+ be eliminated, i.e.:
+\newline
+
+\newline
+
+\family typewriter
\SpecialChar ~
\SpecialChar ~
+pop ar1
+\newline
\SpecialChar ~
\SpecialChar ~
+pop ar2
+\newline
\SpecialChar ~
-character\SpecialChar ~
\SpecialChar ~
+push ar2
+\newline
\SpecialChar ~
\SpecialChar ~
+push ar1
+\family default
+
+\newline
+
+\newline
+would result in:
+\newline
+
+\newline
+
+\family typewriter
\SpecialChar ~
\SpecialChar ~
-char
+pop ar1
\newline
-%s\SpecialChar ~
-\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+; nop
+\newline
\SpecialChar ~
\SpecialChar ~
+push ar1
+\family default
+
+\newline
+
+\newline
+
+\emph on
+with
+\emph default
+ the restart option the rule will be applied again to the resulting code
+ and then all the pop-push pairs will be eliminated to yield:
+\newline
+
+\newline
+
+\family typewriter
\SpecialChar ~
\SpecialChar ~
-character\SpecialChar ~
+; nop
+\newline
\SpecialChar ~
\SpecialChar ~
+; nop
+\family default
+
+\newline
+
+\newline
+A conditional function can be attached to a rule.
+ Attaching rules are somewhat more involved, let me illustrate this with
+ an example.
+\newline
+
+\newline
+
+\family typewriter
+replace {
+\newline
\SpecialChar ~
+ \SpecialChar ~
+ \SpecialChar ~
+ljmp %5
+\newline
+%2:
+\newline
+} by {
+\newline
\SpecialChar ~
-_generic pointer
-\layout Standard
+ \SpecialChar ~
+ \SpecialChar ~
+sjmp %5
+\newline
+%2:
+\newline
+} if labelInRange
+\family default
+
+\newline
+
+\newline
+The optimizer does a look-up of a function name table defined in function
+
+\emph on
+callFuncByName
+\emph default
+ in the source file SDCCpeeph.c, with the name
+\emph on
+labelInRange
+\emph default
+.
+ If it finds a corresponding entry the function is called.
+ Note there can be no parameters specified for these functions, in this
+ case the use of
+\emph on
+%5
+\emph default
+ is crucial, since the function
+\emph on
+labelInRange
+\emph default
+ expects to find the label in that particular variable (the hash table containin
+g the variable bindings is passed as a parameter).
+ If you want to code more such functions, take a close look at the function
+ labelInRange and the calling mechanism in source file SDCCpeeph.c.
+ I know this whole thing is a little kludgey, but maybe some day we will
+ have some better means.
+ If you are looking at this file, you will also see the default rules that
+ are compiled into the compiler, you can add your own rules in the default
+ set there if you get tired of specifying the ---peep-file option.
+\layout Subsection
+
+Pragmas
+\begin_inset LatexCommand \index{Pragmas}
+
+\end_inset
+
-The routine is very stack intesive, --stack-after-data parameter should
- be used when using this routine, the routine also takes about 1K of code
- space.
- It also expects an external function named putchar(char) to be present
- (this can be changed).
- When using the %s format the string / pointer should be cast to a generic
- pointer.
- eg.
\layout Standard
-printf_small(
-\begin_inset Quotes eld
+SDCC supports the following #pragma directives.
+\layout Itemize
+
+SAVE
+\begin_inset LatexCommand \index{\#pragma SAVE}
+
\end_inset
-my str %s, my int %d
-\backslash
-n
-\begin_inset Quotes erd
+ - this will save all current options to the SAVE/RESTORE stack.
+ See RESTORE.
+\layout Itemize
+
+RESTORE
+\begin_inset LatexCommand \index{\#pragma RESTORE}
+
\end_inset
-,(char _generic *)mystr,myint);
+ - will restore saved options from the last save.
+ SAVEs & RESTOREs can be nested.
+ SDCC uses a SAVE/RESTORE stack: SAVE pushes current options to the stack,
+ RESTORE pulls current options from the stack.
+ See SAVE.
\layout Itemize
-stdarg.h - contains definition for the following macros to be used for variable
- parameter list, note that a function can have a variable parameter list
- if and only if it is 'reentrant'
-\begin_deeper
-\layout Standard
+NOGCSE
+\begin_inset LatexCommand \index{\#pragma NOGCSE}
+
+\end_inset
-va_list, va_start, va_arg, va_end.
-\end_deeper
+ - will stop global subexpression elimination.
\layout Itemize
-setjmp.h - contains defintion for ANSI setjmp & longjmp routines.
- Note in this case setjmp & longjmp can be used between functions executing
- within the same register bank, if long jmp is executed from a function
- that is using a different register bank from the function issuing the setjmp
- function, the results may be unpredictable.
- The jump buffer requires 3 bytes of data (the stack pointer & a 16 byte
- return address), and can be placed in any address space.
+NOINDUCTION
+\begin_inset LatexCommand \index{\#pragma NOINDUCTION}
+
+\end_inset
+
+ - will stop loop induction optimizations.
\layout Itemize
-stdlib.h - contains the following functions.
-\begin_deeper
-\layout Standard
+NOJTBOUND
+\begin_inset LatexCommand \index{\#pragma NOJTBOUND}
-atoi, atol.
-\end_deeper
+\end_inset
+
+ - will not generate code for boundary value checking, when switch statements
+ are turned into jump-tables.
\layout Itemize
-string.h - contains the following functions.
-\begin_deeper
-\layout Standard
+NOOVERLAY
+\begin_inset LatexCommand \index{\#pragma NOOVERLAY}
+
+\end_inset
-strcpy, strncpy, strcat, strncat, strcmp, strncmp, strchr, strrchr, strspn,
- strcspn, strpbrk, strstr, strlen, strtok, memcpy, memcmp, memset.
-\end_deeper
+ - the compiler will not overlay the parameters and local variables of a
+ function.
\layout Itemize
-ctype.h - contains the following routines.
-\begin_deeper
-\layout Standard
+LESS_PEDANTIC
+\begin_inset LatexCommand \index{\#pragma LESS\_PEDANTIC}
+
+\end_inset
-iscntrl, isdigit, isgraph, islower, isupper, isprint, ispunct, isspace,
- isxdigit, isalnum, isalpha.
-\end_deeper
+ - the compiler will not warn you anymore for obvious mistakes, you'r on
+ your own now ;-(
\layout Itemize
-malloc.h - The malloc routines are developed by Dmitry S.
- Obukhov (dso@usa.net).
- These routines will allocate memory from the external ram.
- Here is a description on how to use them (as described by the author).
-\begin_deeper
+NOLOOPREVERSE
+\begin_inset LatexCommand \index{\#pragma NOLOOPREVERSE}
+
+\end_inset
+
+ - Will not do loop reversal optimization
+\layout Itemize
+
+EXCLUDE
+\begin_inset LatexCommand \index{\#pragma EXCLUDE}
+
+\end_inset
+
+ NONE | {acc[,b[,dpl[,dph]]] - The exclude pragma disables generation of
+ pair of push/pop instruction in ISR function (using interrupt keyword).
+ The directive should be placed immediately before the ISR function definition
+ and it affects ALL ISR functions following it.
+ To enable the normal register saving for ISR functions use #pragma\SpecialChar ~
+EXCLUDE\SpecialChar ~
+none.
+\layout Itemize
+
+NOIV
+\begin_inset LatexCommand \index{\#pragma NOIV}
+
+\end_inset
+
+ - Do not generate interrupt vector table entries for all ISR functions
+ defined after the pragma.
+ This is useful in cases where the interrupt vector table must be defined
+ manually, or when there is a secondary, manually defined interrupt vector
+ table (e.g.
+ for the autovector feature of the Cypress EZ-USB FX2).
+\layout Itemize
+
+CALLEE-SAVES
+\begin_inset LatexCommand \index{\#pragma CALLEE-SAVES}
+
+\end_inset
+
+ function1[,function2[,function3...]] - The compiler by default uses a caller
+ saves convention for register saving across function calls, however this
+ can cause unneccessary register pushing & popping when calling small functions
+ from larger functions.
+ This option can be used to switch off the register saving convention for
+ the function names specified.
+ The compiler will not save registers when calling these functions, extra
+ code need to be manually inserted at the entry & exit for these functions
+ to save & restore the registers used by these functions, this can SUBSTANTIALLY
+ reduce code & improve run time performance of the generated code.
+ In the future the compiler (with interprocedural analysis) may be able
+ to determine the appropriate scheme to use for each function call.
+ If ---callee-saves command line option is used, the function names specified
+ in #pragma\SpecialChar ~
+CALLEE-SAVES is appended to the list of functions specified in
+ the command line.
\layout Standard
-//Example:
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- #define DYNAMIC_MEMORY_SIZE 0x2000
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- .....
-
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- unsigned char xdata dynamic_memory_pool[DYNAMIC_MEMORY_SIZE];
-\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- unsigned char xdata * current_buffer;
+The pragma's are intended to be used to turn-off certain optimizations which
+ might cause the compiler to generate extra stack / data space to store
+ compiler generated temporary variables.
+ This usually happens in large functions.
+ Pragma directives should be used as shown in the following example, they
+ are used to control options & optimizations for a given function; pragmas
+ should be placed before and/or after a function, placing pragma's inside
+ a function body could have unpredictable results.
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- .....
-
+
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- void main(void)
+
+\family typewriter
+#pragma SAVE
+\begin_inset LatexCommand \index{\#pragma SAVE}
+
+\end_inset
+
+ /* save the current settings */
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- {
+#pragma NOGCSE
+\begin_inset LatexCommand \index{\#pragma NOGCSE}
+
+\end_inset
+
+ /* turnoff global subexpression elimination */
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- ...
-
+#pragma NOINDUCTION
+\begin_inset LatexCommand \index{\#pragma NOINDUCTION}
+
+\end_inset
+
+ /* turn off induction optimizations */
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-//\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- init_dynamic_memory(dynamic_memory_pool,DYNAMIC_MEMORY_SIZE);
+int foo ()
+\newline
+{
\newline
\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //Now it's possible to use malloc.
+ \SpecialChar ~
+ ...
\newline
\SpecialChar ~
+ \SpecialChar ~
+ /* large code */
+\newline
\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
+ \SpecialChar ~
...
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- current_buffer = malloc(0x100);
+}
\newline
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- //
-\end_deeper
-\layout Itemize
+#pragma RESTORE
+\begin_inset LatexCommand \index{\#pragma RESTORE}
-serial.h - Serial IO routines are also developed by Dmitry S.
- Obukhov (dso@usa.net).
- These routines are interrupt driven with a 256 byte circular buffer, they
- also expect external ram to be present.
- Please see documentation in file SDCCDIR/sdcc51lib/serial.c.
- Note the header file
-\begin_inset Quotes eld
\end_inset
-serial.h
-\begin_inset Quotes erd
-\end_inset
+ /* turn the optimizations back on */
+\family default
- MUST be included in the file containing the 'main' function.
-\layout Itemize
+\newline
-ser.h - Alternate serial routine provided by Wolfgang Esslinger <wolfgang@WiredMi
-nds.com> these routines are more compact and faster.
- Please see documentation in file SDCCDIR/sdcc51lib/ser.c
-\layout Itemize
+\newline
+The compiler will generate a warning message when extra space is allocated.
+ It is strongly recommended that the SAVE and RESTORE pragma's be used when
+ changing options for a function.
+\layout Subsection
-ser_ir.h - Another alternate set of serial routines provided by Josef Wolf
- <jw@raven.inka.de>, these routines do not use the external ram.
-\layout Itemize
-reg51.h - contains register definitions for a standard 8051
-\layout Itemize
+\emph on
+<pending: this is messy and incomplete>
+\emph default
+ Library Routines
+\layout Enumerate
-float.h - contains min, max and other floating point related stuff.
-\layout Standard
+Compiler support routines (_gptrget, _mulint etc)
+\layout Enumerate
-All library routines are compiled as --model-small, they are all non-reentrant,
- if you plan to use the large model or want to make these routines reentrant,
- then they will have to be recompiled with the appropriate compiler option.
-\layout Standard
+Stdclib functions (puts, printf, strcat etc)
+\layout Enumerate
-Have not had time to do the more involved routines like printf, will get
- to them shortly.
+Math functions (sin, pow, sqrt etc)
\layout Subsection
Interfacing with Assembly Routines
+\begin_inset LatexCommand \index{Assembly Routines}
+
+\end_inset
+
+
\layout Subsubsection
Global Registers used for Parameter Passing
+\begin_inset LatexCommand \index{Parameter Passing}
+
+\end_inset
+
+
\layout Standard
The compiler always uses the global registers
\emph on
-DPL,DPH,B
+DPL
+\begin_inset LatexCommand \index{DPL}
+
+\end_inset
+
+,DPH
+\begin_inset LatexCommand \index{DPH}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{DPTR}
+
+\end_inset
+
+,B
+\begin_inset LatexCommand \index{B}
+
+\end_inset
+
+
\emph default
and
\emph on
ACC
+\begin_inset LatexCommand \index{ACC}
+
+\end_inset
+
+
\emph default
to pass the first parameter to a routine.
The second parameter onwards is either allocated on the stack (for reentrant
- routines or if --stack-auto is used) or in the internal / external ram
+ routines or if ---stack-auto is used) or in the internal / external ram
(depending on the memory model).
\layout Subsubsection
Assembler Routine(non-reentrant)
+\begin_inset LatexCommand \index{Assembler Routine(non-reentrant)}
+
+\end_inset
+
+
\layout Standard
In the following example the function cfunc calls an assembler routine asm_func,
\layout Subsubsection
Assembler Routine(reentrant)
+\begin_inset LatexCommand \index{Assembler Routine(reentrant)}
+
+\end_inset
+
+
\layout Standard
In this case the second parameter onwards will be passed on the stack, the
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-mov _bp,sp
+mov _bp,sp
\newline
\SpecialChar ~
\SpecialChar ~
\layout Subsection
External Stack
+\begin_inset LatexCommand \index{External Stack}
+
+\end_inset
+
+
\layout Standard
The external stack is located at the start of the external ram segment,
and is 256 bytes in size.
- When --xstack option is used to compile the program, the parameters and
+ When ---xstack option is used to compile the program, the parameters and
local variables of all reentrant functions are allocated in this area.
This option is provided for programs with large stack space requirements.
- When used with the --stack-auto option, all parameters and local variables
+ When used with the ---stack-auto option, all parameters and local variables
are allocated on the external stack (note support libraries will need to
be recompiled with the same options).
\layout Standard
\layout Subsection
ANSI-Compliance
+\begin_inset LatexCommand \index{ANSI-Compliance}
+
+\end_inset
+
+
\layout Standard
Deviations from the compliancy.
\layout Subsection
Cyclomatic Complexity
+\begin_inset LatexCommand \index{Cyclomatic Complexity}
+
+\end_inset
+
+
\layout Standard
Cyclomatic complexity of a function is defined as the number of independent
Use the smallest data type to represent your data-value.
If it is known in advance that the value is going to be less than 256 then
- use a 'char' instead of a 'short' or 'int'.
+ use an 'unsigned char' instead of a 'short' or 'int'.
\layout Itemize
Use unsigned when it is known in advance that the value is not going to
variables (induction).
\layout Itemize
-Since the compiler does not do implicit integral promotion, the programmer
- should do an explicit cast when integral promotion is required.
+Since the compiler does not always do implicit integral promotion, the programme
+r should do an explicit cast when integral promotion is required.
\layout Itemize
Reducing the size of division, multiplication & modulus operations can reduce
\newline
For the modulus operation the variable ch will be promoted to unsigned int
first then the modulus operation will be performed (this will lead to a
- call to support routine _muduint()), and the result will be casted to an
- int.
+ call to support routine _moduint()), and the result will be casted to a
+ char.
If the code is changed to
\newline
compiler will be smart enough to detect such optimization oppurtunities).
\layout Subsection
-Notes on MCS51 memory layout
+Notes on MCS51 memory
+\begin_inset LatexCommand \index{MCS51 memory}
+
+\end_inset
+
+ layout
\layout Standard
The 8051 family of micro controller have a minimum of 128 bytes of internal
\newline
\newline
-Normally the SDCC compiler will only utilise the first bank of registers,
- but it is possible to specify that other banks of registers should be used
- in interrupt routines.
+Normally the SDCC compiler will only utilise the first bank
+\begin_inset LatexCommand \index{bank}
+
+\end_inset
+
+ of registers, but it is possible to specify that other banks of registers
+ should be used in interrupt
+\begin_inset LatexCommand \index{interrupt}
+
+\end_inset
+
+ routines.
By default, the compiler will place the stack after the last bank of used
registers, i.e.
if the first 2 banks of registers are used, it will position the base of
the internal stack at address 16 (0X10).
- This implies that as the stack grows, it will use up the remaining register
- banks, and the 16 bytes used by the 128 bit variables, and 60 bytes for
- general purpose use.
+ This implies that as the stack
+\begin_inset LatexCommand \index{stack}
+
+\end_inset
+
+ grows, it will use up the remaining register banks, and the 16 bytes used
+ by the 128 bit variables, and 60 bytes for general purpose use.
\layout Standard
By default, the compiler uses the 60 general purpose bytes to hold "near
\layout Standard
The amount of stack being used is affected by the use of the "internal stack"
- to save registers before a subroutine call is made (--stack-auto will declare
- parameters and local variables on the stack) and the number of nested subroutin
-es.
+ to save registers before a subroutine call is made (---stack-auto
+\begin_inset LatexCommand \index{---stack-auto}
+
+\end_inset
+
+ will declare parameters and local variables on the stack) and the number
+ of nested subroutines.
\layout Standard
If you detect that the stack is over writing you data, then the following
can be done.
- --xstack will cause an external stack to be used for saving registers and
- (if --stack-auto is being used) storing parameters and local variables.
+ ---xstack will cause an external stack to be used for saving registers
+ and (if ---stack-auto is being used) storing parameters and local variables.
However this will produce more code which will be slower to execute.
\layout Standard
---stack-loc will allow you specify the start of the stack, i.e.
+---stack-loc
+\begin_inset LatexCommand \index{---stack-loc}
+
+\end_inset
+
+ will allow you specify the start of the stack, i.e.
you could start it after any data in the general purpose area.
However this may waste the memory not used by the register banks and if
the size of the "near data" increases, it may creep into the bottom of
the stack.
\layout Standard
---stack-after-data, similar to the --stack-loc, but it automatically places
- the stack after the end of the "near data".
+---stack-after-data
+\begin_inset LatexCommand \index{---stack-after-data}
+
+\end_inset
+
+, similar to the ---stack-loc, but it automatically places the stack after
+ the end of the "near data".
Again this could waste any spare register space.
\layout Standard
---data-loc allows you to specify the start address of the near data.
+---data-loc
+\begin_inset LatexCommand \index{---data-loc}
+
+\end_inset
+
+ allows you to specify the start address of the near data.
This could be used to move the "near data" further away from the stack
giving it more room to grow.
This will only work if no bit variables are being used and the stack can
If you find that the stack is over writing your bit variables or "near data"
then the approach which best utilised the internal memory is to position
the "near data" after the last bank of used registers or, if you use bit
- variables, after the last bit variable by using the --data-loc, e.g.
- if two register banks are being used and no bit variables, --data-loc 16,
- and use the --stack-after-data option.
+ variables, after the last bit variable by using the ---data-loc, e.g.
+ if two register banks are being used and no bit variables, ---data-loc
+ 16, and use the ---stack-after-data option.
\layout Standard
If bit variables are being used, another method would be to try and squeeze
The intermediate code generation assumes the target machine has unlimited
number of registers, and designates them with the name iTemp.
The compiler can be made to dump a human readable form of the code generated
- by using the --dumpraw option.
+ by using the ---dumpraw option.
\layout Itemize
This phase does the bulk of the standard optimizations and is also MCU independe
As mentioned in the optimization section the peep-hole optimizer is rule
based system, which can reprogrammed for other MCUs.
\layout Section
+\pagebreak_top
+SDCDB
+\begin_inset LatexCommand \index{SDCDB}
+
+\end_inset
+
+ - Source Level Debugger
+\begin_inset LatexCommand \index{Debugger}
+
+\end_inset
+
-SDCDB - Source Level Debugger
\layout Standard
SDCC is distributed with a source level debugger.
\SpecialChar \-
debug option must be specified for all files for which debug information
is to be generated.
- The complier generates a .cdb file for each of these files.
- The linker updates the .cdb file with the address information.
+ The complier generates a .adb file for each of these files.
+ The linker creates the .cdb file from the .adb files and the address information.
This .cdb is used by the debugger.
\layout Subsection
How the Debugger Works
\layout Standard
-When the --debug option is specified the compiler generates extra symbol
+When the ---debug option is specified the compiler generates extra symbol
information some of which are put into the the assembler source and some
- are put into the .cdb file, the linker updates the .cdb file with the address
- information for the symbols.
+ are put into the .adb file.
+ Then the linker creates the .cdb file from the individual .adb files with
+ the address information for the symbols.
The debugger reads the symbolic information generated by the compiler &
the address information generated by the linker.
It uses the SIMULATOR (Daniel's S51) to execute the program, the program
Command Line Options.
\layout Itemize
---directory=<source file directory> this option can used to specify the
+---directory=<source file directory> this option can used to specify the
directory search list.
The debugger will look into the directory list specified for source, cdb
& ihx files.
The items in the directory list must be separated by ':', e.g.
if the source files can be in the directories /home/src1 and /home/src2,
- the --directory option should be --directory=/home/src1:/home/src2.
+ the ---directory option should be ---directory=/home/src1:/home/src2.
Note there can be no spaces in the option.
\layout Itemize
My name is Bobby Brown"
\layout Subsection
-Interfacing with XEmacs.
+Interfacing with XEmacs
+\begin_inset LatexCommand \index{XEmacs}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{Emacs}
+
+\end_inset
+
+.
\layout Standard
Two files (in emacs lisp) are provided for the interfacing with XEmacs,
\layout Standard
\SpecialChar ~
-
-\family typewriter
-
-\newline
-;; Current Listing ::
+
+\family typewriter
+
+\newline
+;; Current Listing ::
+\newline
+;;key\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+binding\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+Comment
+\newline
+;;---\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+------\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+--------
+\newline
+;;
+\newline
+;; n\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+ sdcdb-next-from-src\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+SDCDB next command
\newline
-;;key\SpecialChar ~
+;; b\SpecialChar ~
+\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+\SpecialChar ~
+ sdcdb-back-from-src\SpecialChar ~
+\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-binding\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+SDCDB back command
+\newline
+;; c\SpecialChar ~
+\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ sdcdb-cont-from-src\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-Comment
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+SDCDB continue command
\newline
-;;---\SpecialChar ~
+;; s\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+\SpecialChar ~
+ sdcdb-step-from-src\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
--------\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+SDCDB step command
+\newline
+;; ?\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ sdcdb-whatis-c-sexp\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
--------
-\newline
-;;
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+SDCDB ptypecommand for data at
\newline
-;; n\SpecialChar ~
+;;\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- sdcdb-next-from-src\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-SDCDB next command
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+ buffer point
\newline
-;; b\SpecialChar ~
+;; x\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- sdcdb-back-from-src\SpecialChar ~
+ sdcdbsrc-delete\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-SDCDB back command
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+SDCDB Delete all breakpoints if no arg
\newline
-;; c\SpecialChar ~
+;;\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- sdcdb-cont-from-src\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-SDCDB continue command
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+given or delete arg (C-u arg x)
\newline
-;; s\SpecialChar ~
+;; m\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- sdcdb-step-from-src\SpecialChar ~
+ sdcdbsrc-frame\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-SDCDB step command
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+SDCDB Display current frame if no arg,
\newline
-;; ?\SpecialChar ~
+;;\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- sdcdb-whatis-c-sexp\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-SDCDB ptypecommand for data at
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+given or display frame arg
\newline
;;\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- buffer point
+\SpecialChar ~
+buffer point
\newline
-;; x\SpecialChar ~
+;; !\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- sdcdbsrc-delete\SpecialChar ~
+ sdcdbsrc-goto-sdcdb\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+Goto the SDCDB output buffer
+\newline
+;; p\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-SDCDB Delete all breakpoints if no arg
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+ sdcdb-print-c-sexp\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+SDCDB print command for data at
\newline
;;\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-given or delete arg (C-u arg x)
+ buffer point
\newline
-;; m\SpecialChar ~
+;; g\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
- sdcdbsrc-frame\SpecialChar ~
+ sdcdbsrc-goto-sdcdb\SpecialChar ~
+\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+Goto the SDCDB output buffer
+\newline
+;; t\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-SDCDB Display current frame if no arg,
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+ sdcdbsrc-mode\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+Toggles Sdcdbsrc mode (turns it off)
\newline
-;;\SpecialChar ~
+;;
+\newline
+;; C-c C-f\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+\SpecialChar ~
+ sdcdb-finish-from-src\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+SDCDB finish command
+\newline
+;;
+\newline
+;; C-x SPC\SpecialChar ~
+\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ sdcdb-break\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+Set break for line with point
+\newline
+;; ESC t\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ sdcdbsrc-mode\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
-given or display frame arg
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+\SpecialChar ~
+Toggle Sdcdbsrc mode
\newline
-;;\SpecialChar ~
+;; ESC m\SpecialChar ~
+\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+\SpecialChar ~
+ sdcdbsrc-srcmode\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+ Toggle list mode
+\newline
+;;
+\family default
+
+\newline
+
+\layout Section
+\pagebreak_top
+Other Processors
+\layout Subsection
+
+The Z80 and gbz80 port
+\layout Standard
+
+SDCC can target both the Zilog Z80 and the Nintendo Gameboy's Z80-like gbz80.
+ The port is incomplete - long support is incomplete (mul, div and mod are
+ unimplimented), and both float and bitfield support is missing.
+ Apart from that the code generated is correct.
+\layout Standard
+
+As always, the code is the authoritave reference - see z80/ralloc.c and z80/gen.c.
+ The stack frame is similar to that generated by the IAR Z80 compiler.
+ IX is used as the base pointer, HL is used as a temporary register, and
+ BC and DE are available for holding varibles.
+ IY is currently unusued.
+ Return values are stored in HL.
+ One bad side effect of using IX as the base pointer is that a functions
+ stack frame is limited to 127 bytes - this will be fixed in a later version.
+\layout Section
+
+Support
+\begin_inset LatexCommand \index{Support}
+
+\end_inset
+
+
+\layout Standard
+
+SDCC has grown to be a large project.
+ The compiler alone (without the preprocessor, assembler and linker) is
+ about 40,000 lines of code (blank stripped).
+ The open source nature of this project is a key to its continued growth
+ and support.
+ You gain the benefit and support of many active software developers and
+ end users.
+ Is SDCC perfect? No, that's why we need your help.
+ The developers take pride in fixing reported bugs.
+ You can help by reporting the bugs and helping other SDCC users.
+ There are lots of ways to contribute, and we encourage you to take part
+ in making SDCC a great software package.
+\layout Subsection
+
+Reporting Bugs
+\begin_inset LatexCommand \index{Bugs}
+
+\end_inset
+
+
+\begin_inset LatexCommand \index{Reporting Bugs}
+
+\end_inset
+
+
+\layout Standard
+
+Send an email to the mailing list at 'user-sdcc@sdcc.sourceforge.net' or 'devel-sd
+cc@sdcc.sourceforge.net'.
+ Bugs will be fixed ASAP.
+ When reporting a bug, it is very useful to include a small test program
+ which reproduces the problem.
+ If you can isolate the problem by looking at the generated assembly code,
+ this can be very helpful.
+ Compiling your program with the ---dumpall option can sometimes be useful
+ in locating optimization problems.
+\layout Section
+\pagebreak_top
+Compiler internals
+\layout Subsection
+
+The anatomy of the compiler
+\layout Standard
+
+
+\shape italic
+This is an excerpt from an atricle published in Circuit Cellar MagaZine
+ in august 2000.
+ It's a little outdated (the compiler is much more efficient now and user/devell
+oper friendly), but pretty well exposes the guts of it all.
+\shape default
+
+\newline
+
+\newline
+The current version of SDCC can generate code for Intel 8051 and Z80 MCU.
+ It is fairly easy to retarget for other 8-bit MCU.
+ Here we take a look at some of the internals of the compiler.
+
+\layout Paragraph*
+
+Parsing
+\begin_inset LatexCommand \index{Parsing}
+
+\end_inset
+
+
+\layout Standard
+
+Parsing the input source file and creating an AST (Annotated Syntax Tree
+\begin_inset LatexCommand \index{Annotated Syntax Tree}
+
+\end_inset
+
+).
+ This phase also involves propagating types (annotating each node of the
+ parse tree with type information) and semantic analysis.
+ There are some MCU specific parsing rules.
+ For example the storage classes, the extended storage classes are MCU specific
+ while there may be a xdata storage class for 8051 there is no such storage
+ class for z80 or Atmel AVR.
+ SDCC allows MCU specific storage class extensions, i.e.
+ xdata will be treated as a storage class specifier when parsing 8051 C
+ code but will be treated as a C identifier when parsing z80 or ATMEL AVR
+ C code.
+\layout Paragraph*
+
+Generating iCode
+\begin_inset LatexCommand \index{iCode}
+
+\end_inset
+
+
+\layout Standard
+
+Intermediate code generation.
+ In this phase the AST is broken down into three-operand form (iCode).
+ These three operand forms are represented as doubly linked lists.
+ ICode is the term given to the intermediate form generated by the compiler.
+ ICode example section shows some examples of iCode generated for some simple
+ C source functions.
+\layout Paragraph*
+
+Optimizations
+\begin_inset LatexCommand \index{Optimizations}
+
+\end_inset
+
+.
+\layout Standard
+
+Bulk of the target independent optimizations is performed in this phase.
+ The optimizations include constant propagation, common sub-expression eliminati
+on, loop invariant code movement, strength reduction of loop induction variables
+ and dead-code elimination.
+\layout Paragraph*
+
+Live range analysis
+\begin_inset LatexCommand \index{Live range analysis}
+
+\end_inset
+
+
+\layout Standard
+
+During intermediate code generation phase, the compiler assumes the target
+ machine has infinite number of registers and generates a lot of temporary
+ variables.
+ The live range computation determines the lifetime of each of these compiler-ge
+nerated temporaries.
+ A picture speaks a thousand words.
+ ICode example sections show the live range annotations for each of the
+ operand.
+ It is important to note here, each iCode is assigned a number in the order
+ of its execution in the function.
+ The live ranges are computed in terms of these numbers.
+ The from number is the number of the iCode which first defines the operand
+ and the to number signifies the iCode which uses this operand last.
+\layout Paragraph*
+
+Register Allocation
+\begin_inset LatexCommand \index{Register Allocation}
+
+\end_inset
+
+
+\layout Standard
+
+The register allocation determines the type and number of registers needed
+ by each operand.
+ In most MCUs only a few registers can be used for indirect addressing.
+ In case of 8051 for example the registers R0 & R1 can be used to indirectly
+ address the internal ram and DPTR to indirectly address the external ram.
+ The compiler will try to allocate the appropriate register to pointer variables
+ if it can.
+ ICode example section shows the operands annotated with the registers assigned
+ to them.
+ The compiler will try to keep operands in registers as much as possible;
+ there are several schemes the compiler uses to do achieve this.
+ When the compiler runs out of registers the compiler will check to see
+ if there are any live operands which is not used or defined in the current
+ basic block being processed, if there are any found then it will push that
+ operand and use the registers in this block, the operand will then be popped
+ at the end of the basic block.
+
+\layout Standard
+
+There are other MCU specific considerations in this phase.
+ Some MCUs have an accumulator; very short-lived operands could be assigned
+ to the accumulator instead of general-purpose register.
+\layout Paragraph*
+
+Code generation
+\layout Standard
+
+Figure II gives a table of iCode operations supported by the compiler.
+ The code generation involves translating these operations into corresponding
+ assembly code for the processor.
+ This sounds overly simple but that is the essence of code generation.
+ Some of the iCode operations are generated on a MCU specific manner for
+ example, the z80 port does not use registers to pass parameters so the
+ SEND and RECV iCode operations will not be generated, and it also does
+ not support JUMPTABLES.
+
+\newline
+
+\series bold
+\shape italic
+\color red
+<Where is Figure II ?>
+\layout Paragraph*
+
+ICode Example
+\begin_inset LatexCommand \index{ICode Example}
+
+\end_inset
+
+
+\layout Standard
+
+This section shows some details of iCode.
+ The example C code does not do anything useful; it is used as an example
+ to illustrate the intermediate code generated by the compiler.
+\newline
+
+\newline
+
+\family typewriter
+1.\SpecialChar ~
+xdata int * p;
+\newline
+2.\SpecialChar ~
+int gint;
+\newline
+3.\SpecialChar ~
+/* This function does nothing useful.
+ It is used
+\newline
+4.\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+for the purpose of explaining iCode */
+\newline
+5.\SpecialChar ~
+short function (data int *x)
+\newline
+6.\SpecialChar ~
+{
+\newline
+7.\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+short i=10; /* dead initialization eliminated */
+\newline
+8.\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+short sum=10; /* dead initialization eliminated */
+\newline
+9.\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+short mul;
+\newline
+10.\SpecialChar ~
\SpecialChar ~
+int j ;
+\newline
+11.\SpecialChar ~
\SpecialChar ~
+while (*x) *x++ = *p++;
+\newline
+12.\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+sum = 0 ;
+\newline
+13.\SpecialChar ~
\SpecialChar ~
+mul = 0;
+\newline
+14.\SpecialChar ~
\SpecialChar ~
+/* compiler detects i,j to be induction variables */
+\newline
+15.\SpecialChar ~
\SpecialChar ~
+for (i = 0, j = 10 ; i < 10 ; i++, j---) {
+\newline
+16.\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+sum += i;
+\newline
+17.\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+mul += i * 3; /* this multiplication remains */
+\newline
+18.\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
+gint += j * 3;/* this multiplication changed to addition */
+\newline
+19.\SpecialChar ~
\SpecialChar ~
+}
+\newline
+20.\SpecialChar ~
\SpecialChar ~
-buffer point
+return sum+mul;
+\newline
+21.\SpecialChar ~
+}
+\newline
+
+\newline
+
+\family default
+In addition to the operands each iCode contains information about the filename
+ and line it corresponds to in the source file.
+ The first field in the listing should be interpreted as follows:
+\newline
+
+\shape italic
+\size footnotesize
+Filename(linenumber: iCode Execution sequence number : ICode hash table
+ key : loop depth of the iCode).
+\shape default
+\size default
+
+\newline
+Then follows the human readable form of the ICode operation.
+ Each operand of this triplet form can be of three basic types a) compiler
+ generated temporary b) user defined variable c) a constant value.
+ Note that local variables and parameters are replaced by compiler generated
+ temporaries.
+ Live ranges are computed only for temporaries (i.e.
+ live ranges are not computed for global variables).
+ Registers are allocated for temporaries only.
+ Operands are formatted in the following manner:
+\newline
+
+\shape italic
+\size footnotesize
+Operand Name [lr live-from : live-to ] { type information } [ registers
+ allocated ].
+\shape default
+\size default
+
+\newline
+As mentioned earlier the live ranges are computed in terms of the execution
+ sequence number of the iCodes, for example
+\newline
+the iTemp0 is live from (i.e.
+ first defined in iCode with execution sequence number 3, and is last used
+ in the iCode with sequence number 5).
+ For induction variables such as iTemp21 the live range computation extends
+ the lifetime from the start to the end of the loop.
+\newline
+The register allocator used the live range information to allocate registers,
+ the same registers may be used for different temporaries if their live
+ ranges do not overlap, for example r0 is allocated to both iTemp6 and to
+ iTemp17 since their live ranges do not overlap.
+ In addition the allocator also takes into consideration the type and usage
+ of a temporary, for example itemp6 is a pointer to near space and is used
+ as to fetch data from (i.e.
+ used in GET_VALUE_AT_ADDRESS) so it is allocated a pointer registers (r0).
+ Some short lived temporaries are allocated to special registers which have
+ meaning to the code generator e.g.
+ iTemp13 is allocated to a pseudo register CC which tells the back end that
+ the temporary is used only for a conditional jump the code generation makes
+ use of this information to optimize a compare and jump ICode.
+\newline
+There are several loop optimizations performed by the compiler.
+ It can detect induction variables iTemp21(i) and iTemp23(j).
+ Also note the compiler does selective strength reduction, i.e.
+ the multiplication of an induction variable in line 18 (gint = j * 3) is
+ changed to addition, a new temporary iTemp17 is allocated and assigned
+ a initial value, a constant 3 is then added for each iteration of the loop.
+ The compiler does not change the multiplication in line 17 however since
+ the processor does support an 8 * 8 bit multiplication.
+\newline
+Note the dead code elimination optimization eliminated the dead assignments
+ in line 7 & 8 to I and sum respectively.
+\newline
+
+\layout Standard
+
+
+\size footnotesize
+Sample.c (5:1:0:0) _entry($9) :
+\layout Standard
+
+
+\size footnotesize
+Sample.c(5:2:1:0) proc _function [lr0:0]{function short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:3:2:0) iTemp0 [lr3:5]{_near * int}[r2] = recv
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:4:53:0) preHeaderLbl0($11) :
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:5:55:0) iTemp6 [lr5:16]{_near * int}[r0] := iTemp0 [lr3:5]{_near
+ * int}[r2]
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:6:5:1) _whilecontinue_0($1) :
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:7:7:1) iTemp4 [lr7:8]{int}[r2 r3] = @[iTemp6 [lr5:16]{_near *
+ int}[r0]]
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:8:8:1) if iTemp4 [lr7:8]{int}[r2 r3] == 0 goto _whilebreak_0($3)
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:9:14:1) iTemp7 [lr9:13]{_far * int}[DPTR] := _p [lr0:0]{_far
+ * int}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:10:15:1) _p [lr0:0]{_far * int} = _p [lr0:0]{_far * int} + 0x2
+ {short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:13:18:1) iTemp10 [lr13:14]{int}[r2 r3] = @[iTemp7 [lr9:13]{_far
+ * int}[DPTR]]
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:14:19:1) *(iTemp6 [lr5:16]{_near * int}[r0]) := iTemp10 [lr13:14]{int
+}[r2 r3]
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:15:12:1) iTemp6 [lr5:16]{_near * int}[r0] = iTemp6 [lr5:16]{_near
+ * int}[r0] + 0x2 {short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:16:20:1) goto _whilecontinue_0($1)
+\layout Standard
+
+
+\size footnotesize
+Sample.c(11:17:21:0)_whilebreak_0($3) :
+\layout Standard
+
+
+\size footnotesize
+Sample.c(12:18:22:0) iTemp2 [lr18:40]{short}[r2] := 0x0 {short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(13:19:23:0) iTemp11 [lr19:40]{short}[r3] := 0x0 {short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(15:20:54:0)preHeaderLbl1($13) :
+\layout Standard
+
+
+\size footnotesize
+Sample.c(15:21:56:0) iTemp21 [lr21:38]{short}[r4] := 0x0 {short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(15:22:57:0) iTemp23 [lr22:38]{int}[r5 r6] := 0xa {int}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(15:23:58:0) iTemp17 [lr23:38]{int}[r7 r0] := 0x1e {int}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(15:24:26:1)_forcond_0($4) :
+\layout Standard
+
+
+\size footnotesize
+Sample.c(15:25:27:1) iTemp13 [lr25:26]{char}[CC] = iTemp21 [lr21:38]{short}[r4]
+ < 0xa {short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(15:26:28:1) if iTemp13 [lr25:26]{char}[CC] == 0 goto _forbreak_0($7)
+\layout Standard
+
+
+\size footnotesize
+Sample.c(16:27:31:1) iTemp2 [lr18:40]{short}[r2] = iTemp2 [lr18:40]{short}[r2]
+ + ITemp21 [lr21:38]{short}[r4]
+\layout Standard
+
+
+\size footnotesize
+Sample.c(17:29:33:1) iTemp15 [lr29:30]{short}[r1] = iTemp21 [lr21:38]{short}[r4]
+ * 0x3 {short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(17:30:34:1) iTemp11 [lr19:40]{short}[r3] = iTemp11 [lr19:40]{short}[r3]
+ + iTemp15 [lr29:30]{short}[r1]
+\layout Standard
+
+
+\size footnotesize
+Sample.c(18:32:36:1:1) iTemp17 [lr23:38]{int}[r7 r0]= iTemp17 [lr23:38]{int}[r7
+ r0]- 0x3 {short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(18:33:37:1) _gint [lr0:0]{int} = _gint [lr0:0]{int} + iTemp17 [lr23:38]{
+int}[r7 r0]
+\layout Standard
+
+
+\size footnotesize
+Sample.c(15:36:42:1) iTemp21 [lr21:38]{short}[r4] = iTemp21 [lr21:38]{short}[r4]
+ + 0x1 {short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(15:37:45:1) iTemp23 [lr22:38]{int}[r5 r6]= iTemp23 [lr22:38]{int}[r5
+ r6]- 0x1 {short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(19:38:47:1) goto _forcond_0($4)
+\layout Standard
+
+
+\size footnotesize
+Sample.c(19:39:48:0)_forbreak_0($7) :
+\layout Standard
+
+
+\size footnotesize
+Sample.c(20:40:49:0) iTemp24 [lr40:41]{short}[DPTR] = iTemp2 [lr18:40]{short}[r2]
+ + ITemp11 [lr19:40]{short}[r3]
+\layout Standard
+
+
+\size footnotesize
+Sample.c(20:41:50:0) ret iTemp24 [lr40:41]{short}
+\layout Standard
+
+
+\size footnotesize
+Sample.c(20:42:51:0)_return($8) :
+\layout Standard
+
+
+\size footnotesize
+Sample.c(20:43:52:0) eproc _function [lr0:0]{ ia0 re0 rm0}{function short}
+\size default
+
\newline
-;; !\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- sdcdbsrc-goto-sdcdb\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-Goto the SDCDB output buffer
+
\newline
-;; p\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
- sdcdb-print-c-sexp\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-SDCDB print command for data at
+Finally the code generated for this function:
\newline
-;;\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
-\SpecialChar ~
+
+\layout Standard
+
+
+\size footnotesize
+.area DSEG (DATA)
+\layout Standard
+
+
+\size footnotesize
+_p::
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+.ds 2
+\layout Standard
+
+
+\size footnotesize
+_gint::
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+.ds 2
+\layout Standard
+
+
+\size footnotesize
+; sample.c 5
+\layout Standard
+
+
+\size footnotesize
+; ----------------------------------------------
+\layout Standard
+
+
+\size footnotesize
+; function function
+\layout Standard
+
+
+\size footnotesize
+; ----------------------------------------------
+\layout Standard
+
+
+\size footnotesize
+_function:
+\layout Standard
+
+
+\size footnotesize
+; iTemp0 [lr3:5]{_near * int}[r2] = recv
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r2,dpl
+\layout Standard
+
+
+\size footnotesize
+; iTemp6 [lr5:16]{_near * int}[r0] := iTemp0 [lr3:5]{_near * int}[r2]
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov ar0,r2
+\layout Standard
+
+
+\size footnotesize
+;_whilecontinue_0($1) :
+\layout Standard
+
+
+\size footnotesize
+00101$:
+\layout Standard
+
+
+\size footnotesize
+; iTemp4 [lr7:8]{int}[r2 r3] = @[iTemp6 [lr5:16]{_near * int}[r0]]
+\layout Standard
+
+
+\size footnotesize
+; if iTemp4 [lr7:8]{int}[r2 r3] == 0 goto _whilebreak_0($3)
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
- buffer point
-\newline
-;; g\SpecialChar ~
+mov ar2,@r0
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+inc r0
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov ar3,@r0
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+dec r0
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov a,r2
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+orl a,r3
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+jz 00103$
+\layout Standard
+
+
+\size footnotesize
+00114$:
+\layout Standard
+
+
+\size footnotesize
+; iTemp7 [lr9:13]{_far * int}[DPTR] := _p [lr0:0]{_far * int}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
- sdcdbsrc-goto-sdcdb\SpecialChar ~
\SpecialChar ~
+mov dpl,_p
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov dph,(_p + 1)
+\layout Standard
+
+
+\size footnotesize
+; _p [lr0:0]{_far * int} = _p [lr0:0]{_far * int} + 0x2 {short}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov a,#0x02
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+add a,_p
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
-Goto the SDCDB output buffer
-\newline
-;; t\SpecialChar ~
+mov _p,a
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+clr a
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+addc a,(_p + 1)
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov (_p + 1),a
+\layout Standard
+
+
+\size footnotesize
+; iTemp10 [lr13:14]{int}[r2 r3] = @[iTemp7 [lr9:13]{_far * int}[DPTR]]
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+movx a,@dptr
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r2,a
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+inc dptr
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
- sdcdbsrc-mode\SpecialChar ~
\SpecialChar ~
+movx a,@dptr
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r3,a
+\layout Standard
+
+
+\size footnotesize
+; *(iTemp6 [lr5:16]{_near * int}[r0]) := iTemp10 [lr13:14]{int}[r2 r3]
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov @r0,ar2
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+inc r0
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov @r0,ar3
+\layout Standard
+
+
+\size footnotesize
+; iTemp6 [lr5:16]{_near * int}[r0] =
+\layout Standard
+
+
+\size footnotesize
+; iTemp6 [lr5:16]{_near * int}[r0] +
+\layout Standard
+
+
+\size footnotesize
+; 0x2 {short}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+inc r0
+\layout Standard
+
+
+\size footnotesize
+; goto _whilecontinue_0($1)
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+sjmp 00101$
+\layout Standard
+
+
+\size footnotesize
+; _whilebreak_0($3) :
+\layout Standard
+
+
+\size footnotesize
+00103$:
+\layout Standard
+
+
+\size footnotesize
+; iTemp2 [lr18:40]{short}[r2] := 0x0 {short}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
-Toggles Sdcdbsrc mode (turns it off)
-\newline
-;;
-\newline
-;; C-c C-f\SpecialChar ~
+mov r2,#0x00
+\layout Standard
+
+
+\size footnotesize
+; iTemp11 [lr19:40]{short}[r3] := 0x0 {short}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r3,#0x00
+\layout Standard
+
+
+\size footnotesize
+; iTemp21 [lr21:38]{short}[r4] := 0x0 {short}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r4,#0x00
+\layout Standard
+
+
+\size footnotesize
+; iTemp23 [lr22:38]{int}[r5 r6] := 0xa {int}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r5,#0x0A
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
- sdcdb-finish-from-src\SpecialChar ~
\SpecialChar ~
+mov r6,#0x00
+\layout Standard
+
+
+\size footnotesize
+; iTemp17 [lr23:38]{int}[r7 r0] := 0x1e {int}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r7,#0x1E
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r0,#0x00
+\layout Standard
+
+
+\size footnotesize
+; _forcond_0($4) :
+\layout Standard
+
+
+\size footnotesize
+00104$:
+\layout Standard
+
+
+\size footnotesize
+; iTemp13 [lr25:26]{char}[CC] = iTemp21 [lr21:38]{short}[r4] < 0xa {short}
+\layout Standard
+
+
+\size footnotesize
+; if iTemp13 [lr25:26]{char}[CC] == 0 goto _forbreak_0($7)
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
-SDCDB finish command
-\newline
-;;
-\newline
-;; C-x SPC\SpecialChar ~
+clr c
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov a,r4
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+xrl a,#0x80
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+subb a,#0x8a
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
- sdcdb-break\SpecialChar ~
\SpecialChar ~
+jnc 00107$
+\layout Standard
+
+
+\size footnotesize
+00115$:
+\layout Standard
+
+
+\size footnotesize
+; iTemp2 [lr18:40]{short}[r2] = iTemp2 [lr18:40]{short}[r2] +
+\layout Standard
+
+
+\size footnotesize
+; iTemp21 [lr21:38]{short}[r4]
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov a,r4
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+add a,r2
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r2,a
+\layout Standard
+
+
+\size footnotesize
+; iTemp15 [lr29:30]{short}[r1] = iTemp21 [lr21:38]{short}[r4] * 0x3 {short}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov b,#0x03
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov a,r4
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mul ab
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r1,a
+\layout Standard
+
+
+\size footnotesize
+; iTemp11 [lr19:40]{short}[r3] = iTemp11 [lr19:40]{short}[r3] +
+\layout Standard
+
+
+\size footnotesize
+; iTemp15 [lr29:30]{short}[r1]
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
-Set break for line with point
-\newline
-;; ESC t\SpecialChar ~
+add a,r3
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r3,a
+\layout Standard
+
+
+\size footnotesize
+; iTemp17 [lr23:38]{int}[r7 r0]= iTemp17 [lr23:38]{int}[r7 r0]- 0x3 {short}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov a,r7
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+add a,#0xfd
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r7,a
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
- sdcdbsrc-mode\SpecialChar ~
\SpecialChar ~
+mov a,r0
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+addc a,#0xff
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov r0,a
+\layout Standard
+
+
+\size footnotesize
+; _gint [lr0:0]{int} = _gint [lr0:0]{int} + iTemp17 [lr23:38]{int}[r7 r0]
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov a,r7
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+add a,_gint
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov _gint,a
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov a,r0
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
-Toggle Sdcdbsrc mode
-\newline
-;; ESC m\SpecialChar ~
+addc a,(_gint + 1)
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov (_gint + 1),a
+\layout Standard
+
+
+\size footnotesize
+; iTemp21 [lr21:38]{short}[r4] = iTemp21 [lr21:38]{short}[r4] + 0x1 {short}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+inc r4
+\layout Standard
+
+
+\size footnotesize
+; iTemp23 [lr22:38]{int}[r5 r6]= iTemp23 [lr22:38]{int}[r5 r6]- 0x1 {short}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+dec r5
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+cjne r5,#0xff,00104$
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
- sdcdbsrc-srcmode\SpecialChar ~
\SpecialChar ~
+dec r6
+\layout Standard
+
+
+\size footnotesize
+; goto _forcond_0($4)
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+sjmp 00104$
+\layout Standard
+
+
+\size footnotesize
+; _forbreak_0($7) :
+\layout Standard
+
+
+\size footnotesize
+00107$:
+\layout Standard
+
+
+\size footnotesize
+; ret iTemp24 [lr40:41]{short}
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov a,r3
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+add a,r2
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
+mov dpl,a
+\layout Standard
+
+
+\size footnotesize
+; _return($8) :
+\layout Standard
+
+
+\size footnotesize
+00108$:
+\layout Standard
+
+
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
- Toggle list mode
+ret
\newline
-;;
-\family default
+\layout Subsection
+
+A few words about basic block successors, predecessors and dominators
+\layout Standard
+
+Successors are basic blocks that might execute after this basic block.
+\newline
+Predecessors are basic blocks that might execute before reaching this basic
+ block.
+\newline
+Dominators are basic blocks that WILL execute before reaching this basic
+ block.
\newline
-\layout Section
+\layout Standard
-Other Processors
-\layout Subsection
+[basic block 1]
+\layout Standard
-The Z80 and gbz80 port
+if (something)
\layout Standard
-SDCC can target both the Zilog Z80 and the Nintendo Gameboy's Z80-like gbz80.
- The port is incomplete - long support is incomplete (mul, div and mod are
- unimplimented), and both float and bitfield support is missing.
- Apart from that the code generated is correct.
+[basic block 2]
\layout Standard
-As always, the code is the authoritave reference - see z80/ralloc.c and z80/gen.c.
- The stack frame is similar to that generated by the IAR Z80 compiler.
- IX is used as the base pointer, HL is used as a temporary register, and
- BC and DE are available for holding varibles.
- IY is currently unusued.
- Return values are stored in HL.
- One bad side effect of using IX as the base pointer is that a functions
- stack frame is limited to 127 bytes - this will be fixed in a later version.
-\layout Section
+else
+\layout Standard
-Support
+[basic block 3]
\layout Standard
-SDCC has grown to be a large project.
- The compiler alone (without the preprocessor, assembler and linker) is
- about 40,000 lines of code (blank stripped).
- The open source nature of this project is a key to its continued growth
- and support.
- You gain the benefit and support of many active software developers and
- end users.
- Is SDCC perfect? No, that's why we need your help.
- The developers take pride in fixing reported bugs.
- You can help by reporting the bugs and helping other SDCC users.
- There are lots of ways to contribute, and we encourage you to take part
- in making SDCC a great software package.
-\layout Subsection
+[basic block 4]
+\newline
-Reporting Bugs
\layout Standard
-Send an email to the mailing list at 'user-sdcc@sdcc.sourceforge.net' or 'devel-sd
-cc@sdcc.sourceforge.net'.
- Bugs will be fixed ASAP.
- When reporting a bug, it is very useful to include a small test program
- which reproduces the problem.
- If you can isolate the problem by looking at the generated assembly code,
- this can be very helpful.
- Compiling your program with the --dumpall option can sometimes be useful
- in locating optimization problems.
+a) succList of [BB2] = [BB4], of [BB3] = [BB4], of [BB1] = [BB2,BB3]
+\layout Standard
+
+b) predList of [BB2] = [BB1], of [BB3] = [BB1], of [BB4] = [BB2,BB3]
+\layout Standard
+
+c) domVect of [BB4] = BB1 ...
+ here we are not sure if BB2 or BB3 was executed but we are SURE that BB1
+ was executed.
\layout Section
Acknowledgments
\layout Standard
-Sandeep Dutta (sandeep.dutta@usa.net) - SDCC, the compiler, MCS51 code generator,
- Debugger, AVR port
-\newline
-Alan Baldwin (baldwin@shop-pdp.kent.edu) - Initial version of ASXXXX & ASLINK.
-
-\newline
-John Hartman (jhartman@compuserve.com) - Porting ASXXX & ASLINK for 8051
-\newline
-Dmitry S.
- Obukhov (dso@usa.net) - malloc & serial i/o routines.
-
-\newline
-Daniel Drotos (drdani@mazsola.iit.uni-miskolc.hu) - for his Freeware simulator
-\newline
-Malini Dutta(malini_dutta@hotmail.com) - my wife for her patience and support.
-\newline
-Unknown - for the GNU C - preprocessor.
-\newline
-Michael Hope - The Z80 and Z80GB port, 186 development
-\newline
-Kevin Vigor - The DS390 port.
-\newline
-Johan Knol - Lots of fixes and enhancements, DS390/TINI libs.
-\newline
-Scott Datallo - The PIC port.
+
+\begin_inset LatexCommand \url{http://sdcc.sourceforge.net#Who}
+
+\end_inset
+
+
\newline
\newline
All product names mentioned herein may be trademarks of their respective
companies.
+\layout Section
+
+Alphabetical index
+\layout Standard
+
+To avoid confusion, the installation and building options for sdcc itself
+ (chapter 2) are not part of the index.
\layout Standard
projects / fw / sdcc / blobdiff