\papersides 1
\paperpagestyle fancy
-\layout Title
-
-
-\begin_inset ERT
-status Open
-
-\layout Standard
+\layout Comment
-\backslash
-NotSpecial{
-\backslash
-do
-\backslash
--}
-\end_inset
+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 Standard
\newline
\newline
-SDCC also provides an option (---cyclomatic) to report the relative complexity
+SDCC also provides an option (--cyclomatic) to report the relative complexity
of a function.
These functions can then be further optimized, or hand coded in assembly
if needed.
\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
(8 bits) which is not ANSI compliant
\layout Itemize
-the default directory where include, library and documention files are stored
- is now 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
-\family typewriter
---
-\family default
-regextend has been removed
+option ---regextend has been removed
\layout Itemize
-option --noregparms has been removed
+option ---noregparms has been removed
\layout Itemize
-option --stack-after-data 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
Install and search paths
\layout Standard
-Linux (and other gcc-builds like Solaris, Cygwin, Mingw and OSX) by default
+Linux (and other gcc-builds like Solaris, Cygwin, Mingw32 and OSX) by default
install in /usr/local.
- You can override this when configuring with --prefix-path.
+ You can override this when configuring with ---prefix-path.
Subdirs used will be bin, share/sdcc/include, share/sdcc/lib and share/sdcc/doc.
\newline
Windows MSVC and Borland builds will install in one single tree (e.g.
\begin_inset Quotes sld
\end_inset
-SDCCHOME)/include
+SDCCHOME
+\begin_inset Quotes srd
+\end_inset
+
+)/include
\newline
- /usr/local/share/sdcc/include (gcc builds)
\newline
-- path(arv[0])/../include and then /sdcc/include (windoze msvc and borland
- builds)
+- path(arv[0])/../include and then /sdcc/include (as a last resort for windoze
+ msvc and borland builds)
\layout Enumerate
Library files (the
\shape italic
model
\shape default
- (windoze msvc and borland builds)
+ (as a last resort for windoze msvc and borland builds)
\layout Enumerate
Documentation (although never really searched for, you have to do that yourself
\layout Standard
So, for windoze it is highly recommended to set the environment variable
- SDCCHOME to prevent needless usage of -I and -L.
+ SDCCHOME to prevent needless usage of -I and -L options.
+ For gcc-builds SDCCHOME should only be set when sdcc is installed in non-standa
+rd paths.
\layout Subsection
-Linux and other gcc-based systems (cygwin, mingw, osx)
+Linux and other gcc-based systems (cygwin, mingw32, osx)
\layout Enumerate
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 mingw package is: c:
+ An example directory structure after unpacking the mingw32 package is:
+ c:
\backslash
usr
\backslash
directory or start sdcc using the full path.
\layout Subsubsection
-Windows Install Using Cygwin and Mingw
+Windows Install Using Cygwin and Mingw32
\layout Standard
Follow the instruction in
bin, and you can compile using sdcc.
\layout Subsubsection
-Windows Install Using Borland ......
-\layout Standard
+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
-\shape italic
-<pending>
+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
+
+\newline
+
+\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
+or on Windows NT/2000/XP from the command prompt with the commmand:
+\newline
+
+\family sans
+\series bold
+
+\newline
+del /s *.obj *.lib *.rul
+\family default
+\series default
+ from the sdcc directory.
\layout Subsection
Testing out the SDCC Compiler
Type
\family sans
\series bold
-"sdcc --version"
+"sdcc ---version"
\family default
\series default
at the prompt, and the program should run and tell you the version.
\newline
\series medium
-SDCC binaries are commonly installed in a directory arrangement like this:
-\series default
-
-\newline
-
-\newline
-
-\begin_inset Tabular
-<lyxtabular version="3" rows="3" columns="2">
-<features>
-<column alignment="left" valignment="top" leftline="true" width="0(null)">
-<column alignment="left" valignment="top" leftline="true" rightline="true" width="0(null)">
-<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
-\end_inset
-</cell>
-<cell alignment="center" valignment="top" topline="true" leftline="true" rightline="true" usebox="none">
-\begin_inset Text
-
-\layout Standard
-
-
-\series medium
-Holds executables(sdcc, s51, aslink,
-\series default
-...
-\series medium
-)
-\end_inset
-</cell>
-</row>
-<row topline="true">
-<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
-\begin_inset Text
-
-\layout Standard
-
-/
-\series medium
-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 medium
-Holds common C
+SDCC
\series default
-libraries
-\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 medium
-usr/local/share/sdcc/include
-\end_inset
-</cell>
-<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
+is commonly installed as described in section
+\begin_inset Quotes sld
\end_inset
-</cell>
-</row>
-</lyxtabular>
+Install and search paths
+\begin_inset Quotes srd
\end_inset
\series medium
Make sure the compiler works on a very simple example.
- Type in the following test.c program using your favorite editor:
+ Type in the following test.c program using your favorite
+\series default
+ascii
+\series medium
+editor:
\series default
\newline
\newline
-\family typewriter
+\family sans
+\series bold
./configure 2>&1 | tee configure.log
\family default
+\series default
\newline
\newline
-\family typewriter
+\family sans
+\series bold
make 2>&1 | tee make.log
\family default
+\series default
\newline
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.
- On most systems you will need super-user privilages to do this.
-\layout Subsection
-
-Advanced Install Options
-\layout Standard
-
-The
-\begin_inset Quotes eld
-\end_inset
-
-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 for DS80C390 library
-\newline
-bin/share/sdcc/lib/z80/ - Object & library files for Z80 library
-\newline
-
-\newline
-The command
-\family sans
-\series bold
-
+This will install the compiler, other executables libraries and include
+ files in to the appropriate directories.
+ See section
\begin_inset Quotes sld
\end_inset
-./configure --prefix=/usr/local
-\begin_inset Quotes erd
+Install and Search PATHS
+\begin_inset Quotes srd
\end_inset
-
-\family default
-\series default
-will configure the compiler to be installed in directory /usr/local.
+.
+\newline
+On most systems you will need super-user privilages to do this.
\layout Subsection
Components of SDCC
\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:
+ At the time of this writing, we find the following programs for gcc-builds:
\newline
\newline
In <installdir>/share/sdcc/lib
\layout Itemize
-the sources of the runtime library and the subdirs small large and ds390
- with the precompiled relocatables.
+the subdirs src and small, large, z80, gbz80 and ds390 with the precompiled
+ relocatables.
\layout Standard
In <installdir>/share/sdcc/doc
\family typewriter
\shape italic
-<todo: is this thing alive?>
+<todo: is this thing still alive?>
\newline
\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)
+ Motorola S19 format with ---out-fmt-s19)
\newline
-sourcefile.cdb - An optional file (with --debug) containing debug information
+sourcefile.cdb - An optional file (with ---debug) containing debug information
\newline
+sourcefile.dump* - 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
Projects with Multiple Source Files
\labelwidthstring 00.00.0000
-\series bold
--o\SpecialChar ~
-<path/file>
-\series default
-the output path resp.
- file where everything will be placed
-\layout List
-\labelwidthstring 00.00.0000
-
-
\series bold
-L\SpecialChar ~
---lib-path
+---lib-path
\bar under
\series default
\series bold
---xram-loc
+---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.
+ 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
\series bold
---code-loc
+---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.
+ 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
\series bold
---stack-loc
+---stack-loc
\series 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.
+ ---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
\series bold
---data-loc
+---data-loc
\series default
<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.
+ ---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.)
+ data segment will be set, if ---data-loc is not used, to location 0x10.)
\layout List
\labelwidthstring 00.00.0000
\series bold
---idata-loc
+---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.
+ ---idata-loc 0x88 or ---idata-loc 136.
\layout List
\labelwidthstring 00.00.0000
\series bold
---out-fmt-ihx
+---out-fmt-ihx
\bar under
\series default
\series bold
---out-fmt-s19
+---out-fmt-s19
\bar under
\series default
\series bold
---model-large
+---model-large
\series default
Generate code for Large model programs see section Memory Models for more
details.
\series bold
---model-small
+---model-small
\series default
\size large
\emph on
\series bold
---model-flat24
+---model-flat24
\series default
\size large
\emph on
\series bold
---stack-10bit
+---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
any re-entrant functions compiled with this option.
In principle, this should work with the
\emph on
---stack-auto
+---stack-auto
\emph default
option, but that has not been tested.
It is incompatible with the
\emph on
---xstack
+---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
+---model-flat24 option
\emph default
).
\layout Subsubsection
\series bold
---nogcse
+---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
\series bold
---noinvariant
+---noinvariant
\series default
Will not do loop invariant optimizations, this may be turned off for reasons
explained for the previous option.
\series bold
---noinduction
+---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 ~
\series bold
---nojtbound
+---nojtbound
\size large
\bar under
\series bold
---noloopreverse
+---noloopreverse
\series default
\size large
\layout List
\labelwidthstring 00.00.0000
+---
+\series bold
+nolabelopt
+\series default
+ Will not optimize labels (makes the dumpfiles more readable).
+\layout List
+\labelwidthstring 00.00.0000
+
\series bold
---no-xinit-opt
+---no-xinit-opt
\series default
- This will disable the memcpy of initialized data in far space from code
- space
+ 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
\series bold
-c\SpecialChar ~
---compile-only
+---compile-only
\series default
will compile and assemble the source, but will not call the linkage editor.
\layout List
\labelwidthstring 00.00.0000
+\series bold
+--c1mode
+\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
\series default
\series bold
---stack-auto
+-o\SpecialChar ~
+<path/file>
+\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
\series default
\size large
\emph on
\series bold
---xstack
+---xstack
\series default
Uses a pseudo stack in the first 256 bytes in the external ram for allocating
variables and passing parameters.
\series bold
---callee-saves function1[,function2][,function3]....
+---callee-saves function1[,function2][,function3]....
\series default
The compiler by default uses a caller saves convention for register saving
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.
+ should be compiled with the same ---callee-saves option string.
Also see #pragma\SpecialChar ~
CALLEE-SAVES.
\layout List
\series bold
---debug
+---debug
\bar under
\series default
\series bold
---peep-file
+---peep-file
\series default
<filename> This option can be used to use additional rules to be used by
the peep hole optimizer.
\series bold
---int-long-reent
+---int-long-reent
\series default
\size large
\series bold
---cyclomatic
+---cyclomatic
\bar under
\series default
\series bold
---float-reent
+---float-reent
\bar under
\series default
\series bold
---nooverlay
+---nooverlay
\series default
The compiler will not overlay parameters and local variables of any function,
see section Parameters and local variables for more details.
\series bold
---main-return
+---main-return
\series default
This option can be used when the code generated is called by a monitor
program.
\series bold
---no-peep
+---no-peep
\series default
Disable peep-hole optimization.
\layout List
\series bold
---peep-asm
+---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
\series bold
---iram-size
+---iram-size
\series default
<Value> Causes the linker to check if the internal ram usage is within limits
of the given value.
\series bold
---xram-size
+---xram-size
\series default
<Value> Causes the linker to check if the external ram usage is within limits
of the given value.
\series bold
---code-size
+---code-size
\series default
<Value> Causes the linker to check if the code usage is within limits of
the given value.
\series bold
---nostdincl
+---nostdincl
\series default
This will prevent the compiler from passing on the default include path
to the preprocessor.
\series bold
---nostdlib
+---nostdlib
\series default
This will prevent the compiler from passing on the default library path
to the linker.
\series bold
---verbose
+---verbose
\series default
Shows the various actions the compiler is performing.
\layout List
-V
\series default
Shows the actual commands the compiler is executing.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+---no-c-code-in-asm
+\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
+\series default
+ Include i-codes in the asm file.
+ Looks like noise but is most helpfull for debugging the compiler itself.
\layout Subsubsection
Intermediate Dump Options
\series bold
---dumpraw
+---dumpraw
\series default
This option will cause the compiler to dump the intermediate code into
a file of named
\series bold
---dumpgcse
+---dumpgcse
\series default
Will create a dump of iCode's, after global subexpression elimination,
into a file named
\series bold
---dumpdeadcode
+---dumpdeadcode
\series default
Will create a dump of iCode's, after deadcode elimination, into a file
named
\series bold
---dumploop
+---dumploop
\series default
\size large
\series bold
---dumprange
+---dumprange
\series default
\size large
\series bold
---dumlrange
+---dumlrange
\series default
Will dump the life ranges for all symbols.
\layout List
\series bold
---dumpregassign
+---dumpregassign
\bar under
\series default
\series bold
---dumplrange
+---dumplrange
\series default
Will create a dump of the live ranges of iTemp's
\layout List
\series bold
---dumpall
+---dumpall
\size large
\bar under
Will cause all the above mentioned dumps to be created.
\layout Subsection
-MCS51/DS390 Storage Class Language Extensions
+Environment variables
\layout Standard
-In addition to the ANSI storage classes SDCC allows the following MCS51
- specific storage classes.
-\layout Subsubsection
+SDCC recognizes the following environment variables:
+\layout List
+\labelwidthstring 00.00.0000
-xdata
-\layout Standard
-Variables declared with this storage class will be placed in the extern
- RAM.
- This is the
\series bold
-default
+SDCC_LEAVE_SIGNALS
\series default
- storage class for Large Memory model, e.g.:
-\newline
+ SDCC installs a signal handler 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
-\newline
-\family typewriter
-xdata unsigned char xduc;
-\layout Subsubsection
+\series bold
+TMP,\SpecialChar ~
+TEMP,\SpecialChar ~
+TMPDIR
+\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
-data
-\layout Standard
-This is the
\series bold
-default
+(coming\SpecialChar ~
+soon:\SpecialChar ~
+SDCC_BIN_PATH)
\series default
- storage class for Small Memory model.
- Variables declared with this storage class will be allocated in the internal
- RAM, e.g.:
-\newline
+ Path, see
+\begin_inset Quotes sld
+\end_inset
-\newline
+2.1 Install and search paths
+\begin_inset Quotes srd
+\end_inset
-\family typewriter
-data int iramdata;
-\layout Subsubsection
+.
+\layout List
+\labelwidthstring 00.00.0000
-idata
-\layout Standard
-Variables declared with this storage class will be allocated into the indirectly
+\series bold
+(coming\SpecialChar ~
+soon:\SpecialChar ~
+SDCC_INCLUDE_PATH)
+\series default
+ Path, see
+\begin_inset Quotes sld
+\end_inset
+
+2.1 Install and search paths
+\begin_inset Quotes srd
+\end_inset
+
+.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+(coming\SpecialChar ~
+soon:\SpecialChar ~
+SDCC_LIB_PATH)
+\series default
+ Path, see
+\begin_inset Quotes sld
+\end_inset
+
+2.1 Install and search paths
+\begin_inset Quotes srd
+\end_inset
+
+.
+\layout List
+\labelwidthstring 00.00.0000
+
+
+\series bold
+SDCCDIR\SpecialChar ~
+(soon\SpecialChar ~
+replaced\SpecialChar ~
+by:\SpecialChar ~
+SDCCPATH)
+\series default
+ Path, see
+\begin_inset Quotes sld
+\end_inset
+
+2.1 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 Language Extensions
+\layout Standard
+
+In addition to the ANSI storage classes SDCC allows the following MCS51
+ specific storage classes.
+\layout Subsubsection
+
+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
+
+\newline
+
+\family typewriter
+xdata unsigned char xduc;
+\layout Subsubsection
+
+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
+
+\newline
+
+\family typewriter
+data int iramdata;
+\layout Subsubsection
+
+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
\newline
They can be placed on the stack either by using the
\emph on
- --stack-auto
+ ---stack-auto
\emph default
option or by using the
\emph on
\emph default
keyword or the
\emph on
- --stack-auto
+ ---stack-auto
\emph default
option should be used sparingly.
Note that the reentrant keyword just means that the parameters & local
in internal ram.
When compiled with
\emph on
---stack-auto
+---stack-auto
\emph default
or when a function is declared as
\emph on
these operations then the support routines (as mentioned in a following
section) will have to be recompiled using the
\emph on
- --stack-auto
+ ---stack-auto
\emph default
option and the source file will need to be compiled using the
\emph on
---int-long-ren
+---int-long-ren
\emph default
t compiler option.
\layout Standard
\begin_inset Tabular
<lyxtabular version="3" rows="6" columns="3">
<features>
-<column alignment="center" valignment="top" leftline="true" width="0(null)">
-<column alignment="center" valignment="top" leftline="true" width="0(null)">
-<column alignment="center" valignment="top" leftline="true" rightline="true" width="0(null)">
+<column alignment="center" valignment="top" leftline="true" width="0pt">
+<column alignment="center" valignment="top" leftline="true" width="0pt">
+<column alignment="center" valignment="top" leftline="true" rightline="true" width="0pt">
<row topline="true" bottomline="true">
<cell alignment="center" valignment="top" topline="true" leftline="true" usebox="none">
\begin_inset Text
be placed in a separate line (as the example shows).
When the
\emph on
---peep-asm
+---peep-asm
\emph default
command line option is used, the inline assembler code will be passed through
the peephole optimizer.
labels defines in inline assembly CANNOT be accessed by C statements.
\layout Subsection
-int(16 bit) and long (32 bit) Support
+int (16 bit) and long (32 bit) Support
\layout Standard
For signed & unsigned int (16 bit) and long (32 bit) variables, division,
If this is unavoidable then the above routines will need to be compiled
with the
\emph on
---stack-auto
+---stack-auto
\emph default
option, after which the source program will have to be compiled with
\emph on
---int-long-rent
+---int-long-rent
\emph default
option.
\layout Subsection
\newline
Like the
\emph on
---model-large
+---model-large
\emph default
option, variables will by default be placed into the XDATA segment.
\newline
Segments may be placed anywhere in the 4 meg address space using the usual
- --*-loc options.
+ ---*-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.
SDCC_STACK_AUTO - this symbol is defined when
\emph on
---stack-auto
+---stack-auto
\emph default
option is used.
\layout Itemize
SDCC_MODEL_SMALL - when
\emph on
---model-small
+---model-small
\emph default
is used.
\layout Itemize
SDCC_MODEL_LARGE - when
\emph on
---model-large
+---model-large
\emph default
is used.
\layout Itemize
SDCC_USE_XSTACK - when
\emph on
---xstack
+---xstack
\emph default
option is used.
\layout Itemize
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
+ can be eliminated either for the entire source file (with ---noinduction
option) or for a given function only using #pragma\SpecialChar ~
NOINDUCTION.
\newline
A default set of rules are compiled into the compiler, additional rules
may be added with the
\emph on
---peep-file <filename>
+---peep-file <filename>
\emph default
option.
The rule language is best illustrated with examples.
\newline
Other special case optimizations may be added by the user (via
\emph on
---peep-file option
+---peep-file option
\emph default
).
E.g.
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.
+ set there if you get tired of specifying the ---peep-file option.
\layout Subsection
Pragmas
none.
\layout Itemize
+NOIV - 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 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
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
+ 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.
\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
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
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
\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 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 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
+---stack-after-data, 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 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
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.
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
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
--------\SpecialChar ~
+------\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
\SpecialChar ~
--------
+--------
\newline
;;
\newline
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
+ Compiling your program with the ---dumpall option can sometimes be useful
in locating optimization problems.
\layout Section
+Compiler internals
+\layout Subsection
+
The anatomy of the compiler
\layout Standard
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
+\layout Paragraph*
Generating iCode
\layout Standard
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
+\layout Paragraph*
Optimizations.
\layout Standard
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
+\layout Paragraph*
Live range analysis
\layout Standard
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
+\layout Paragraph*
Register Allocation
\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
+\layout Paragraph*
Code generation
\layout Standard
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
-\layout Section*
+ not support JUMPTABLES.
+
+\newline
+\series bold
+\shape italic
+\color red
<Where is Figure II ?>
-\layout Paragraph
+\layout Paragraph*
ICode Example
\layout Standard
\newline
15.\SpecialChar ~
\SpecialChar ~
-for (i = 0, j = 10 ; i < 10 ; i++, j--) {
+for (i = 0, j = 10 ; i < 10 ; i++, j---) {
\newline
16.\SpecialChar ~
\SpecialChar ~
\newline
\shape italic
+\size footnotesize
Filename(linenumber: iCode Execution sequence number : ICode hash table
key : loop depth of the iCode).
-\newline
-
\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.
\newline
\shape italic
+\size footnotesize
Operand Name [lr live-from : live-to ] { type information } [ registers
allocated ].
-\newline
-
\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
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c (5:1:0:0) _entry($9) :
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(5:2:1:0) proc _function [lr0:0]{function short}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:3:2:0) iTemp0 [lr3:5]{_near * int}[r2] = recv
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:4:53:0) preHeaderLbl0($11) :
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:5:55:0) iTemp6 [lr5:16]{_near * int}[r0] := iTemp0 [lr3:5]{_near
* int}[r2]
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:6:5:1) _whilecontinue_0($1) :
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:7:7:1) iTemp4 [lr7:8]{int}[r2 r3] = @[iTemp6 [lr5:16]{_near *
int}[r0]]
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:8:8:1) if iTemp4 [lr7:8]{int}[r2 r3] == 0 goto _whilebreak_0($3)
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:9:14:1) iTemp7 [lr9:13]{_far * int}[DPTR] := _p [lr0:0]{_far
* int}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:10:15:1) _p [lr0:0]{_far * int} = _p [lr0:0]{_far * int} + 0x2
{short}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:13:18:1) iTemp10 [lr13:14]{int}[r2 r3] = @[iTemp7 [lr9:13]{_far
* int}[DPTR]]
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:14:19:1) *(iTemp6 [lr5:16]{_near * int}[r0]) := iTemp10 [lr13:14]{int
}[r2 r3]
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:15:12:1) iTemp6 [lr5:16]{_near * int}[r0] = iTemp6 [lr5:16]{_near
- * int}[r0] +
-\layout Standard
-
-
-\family typewriter
-0x2 {short}
+ * int}[r0] + 0x2 {short}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:16:20:1) goto _whilecontinue_0($1)
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(11:17:21:0)_whilebreak_0($3) :
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(12:18:22:0) iTemp2 [lr18:40]{short}[r2] := 0x0 {short}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(13:19:23:0) iTemp11 [lr19:40]{short}[r3] := 0x0 {short}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(15:20:54:0)preHeaderLbl1($13) :
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(15:21:56:0) iTemp21 [lr21:38]{short}[r4] := 0x0 {short}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(15:22:57:0) iTemp23 [lr22:38]{int}[r5 r6] := 0xa {int}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(15:23:58:0) iTemp17 [lr23:38]{int}[r7 r0] := 0x1e {int}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(15:24:26:1)_forcond_0($4) :
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(15:25:27:1) iTemp13 [lr25:26]{char}[CC] = iTemp21 [lr21:38]{short}[r4]
< 0xa {short}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(15:26:28:1) if iTemp13 [lr25:26]{char}[CC] == 0 goto _forbreak_0($7)
\layout Standard
-\family typewriter
+\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
-\family typewriter
-ITemp21 [lr21:38]{short}[r4]
-\layout Standard
-
-
-\family typewriter
+\size footnotesize
Sample.c(17:29:33:1) iTemp15 [lr29:30]{short}[r1] = iTemp21 [lr21:38]{short}[r4]
* 0x3 {short}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(17:30:34:1) iTemp11 [lr19:40]{short}[r3] = iTemp11 [lr19:40]{short}[r3]
- +
-\layout Standard
-
-
-\family typewriter
-iTemp15 [lr29:30]{short}[r1]
+ + iTemp15 [lr29:30]{short}[r1]
\layout Standard
-\family typewriter
+\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
-\family typewriter
+\size footnotesize
Sample.c(18:33:37:1) _gint [lr0:0]{int} = _gint [lr0:0]{int} + iTemp17 [lr23:38]{
int}[r7 r0]
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(15:36:42:1) iTemp21 [lr21:38]{short}[r4] = iTemp21 [lr21:38]{short}[r4]
+ 0x1 {short}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(15:37:45:1) iTemp23 [lr22:38]{int}[r5 r6]= iTemp23 [lr22:38]{int}[r5
r6]- 0x1 {short}
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(19:38:47:1) goto _forcond_0($4)
\layout Standard
-\family typewriter
+\size footnotesize
Sample.c(19:39:48:0)_forbreak_0($7) :
\layout Standard
-\family typewriter
+\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
-\family typewriter
-ITemp11 [lr19:40]{short}[r3]
+\size footnotesize
+Sample.c(20:41:50:0) ret iTemp24 [lr40:41]{short}
\layout Standard
-\family typewriter
-sample.c(20:41:50:0) ret iTemp24 [lr40:41]{short}
+\size footnotesize
+Sample.c(20:42:51:0)_return($8) :
\layout Standard
-\family typewriter
-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
-\family typewriter
-sample.c(20:43:52:0) eproc _function [lr0:0]{ ia0 re0 rm0}{function short}
\newline
-\family default
-
\newline
Finally the code generated for this function:
\newline
\layout Standard
-\family typewriter
+\size footnotesize
.area DSEG (DATA)
\layout Standard
-\family typewriter
+\size footnotesize
_p::
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
.ds 2
\layout Standard
-\family typewriter
+\size footnotesize
_gint::
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
.ds 2
\layout Standard
-\family typewriter
+\size footnotesize
; sample.c 5
\layout Standard
-\family typewriter
-; -----------------------------------------
+\size footnotesize
+; ----------------------------------------------
\layout Standard
-\family typewriter
+\size footnotesize
; function function
\layout Standard
-\family typewriter
-; -----------------------------------------
+\size footnotesize
+; ----------------------------------------------
\layout Standard
-\family typewriter
+\size footnotesize
_function:
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp0 [lr3:5]{_near * int}[r2] = recv
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r2,dpl
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp6 [lr5:16]{_near * int}[r0] := iTemp0 [lr3:5]{_near * int}[r2]
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov ar0,r2
\layout Standard
-\family typewriter
+\size footnotesize
;_whilecontinue_0($1) :
\layout Standard
-\family typewriter
+\size footnotesize
00101$:
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp4 [lr7:8]{int}[r2 r3] = @[iTemp6 [lr5:16]{_near * int}[r0]]
\layout Standard
-\family typewriter
+\size footnotesize
; if iTemp4 [lr7:8]{int}[r2 r3] == 0 goto _whilebreak_0($3)
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov ar2,@r0
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
inc r0
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov ar3,@r0
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
dec r0
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov a,r2
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
orl a,r3
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
jz 00103$
\layout Standard
-\family typewriter
+\size footnotesize
00114$:
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp7 [lr9:13]{_far * int}[DPTR] := _p [lr0:0]{_far * int}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov dpl,_p
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov dph,(_p + 1)
\layout Standard
-\family typewriter
+\size footnotesize
; _p [lr0:0]{_far * int} = _p [lr0:0]{_far * int} + 0x2 {short}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov a,#0x02
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
add a,_p
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov _p,a
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
clr a
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
addc a,(_p + 1)
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov (_p + 1),a
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp10 [lr13:14]{int}[r2 r3] = @[iTemp7 [lr9:13]{_far * int}[DPTR]]
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
movx a,@dptr
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r2,a
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
inc dptr
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
movx a,@dptr
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r3,a
\layout Standard
-\family typewriter
+\size footnotesize
; *(iTemp6 [lr5:16]{_near * int}[r0]) := iTemp10 [lr13:14]{int}[r2 r3]
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov @r0,ar2
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
inc r0
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov @r0,ar3
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp6 [lr5:16]{_near * int}[r0] =
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp6 [lr5:16]{_near * int}[r0] +
\layout Standard
-\family typewriter
+\size footnotesize
; 0x2 {short}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
inc r0
\layout Standard
-\family typewriter
+\size footnotesize
; goto _whilecontinue_0($1)
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
sjmp 00101$
\layout Standard
-\family typewriter
+\size footnotesize
; _whilebreak_0($3) :
\layout Standard
-\family typewriter
+\size footnotesize
00103$:
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp2 [lr18:40]{short}[r2] := 0x0 {short}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r2,#0x00
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp11 [lr19:40]{short}[r3] := 0x0 {short}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r3,#0x00
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp21 [lr21:38]{short}[r4] := 0x0 {short}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r4,#0x00
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp23 [lr22:38]{int}[r5 r6] := 0xa {int}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r5,#0x0A
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r6,#0x00
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp17 [lr23:38]{int}[r7 r0] := 0x1e {int}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r7,#0x1E
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r0,#0x00
\layout Standard
-\family typewriter
+\size footnotesize
; _forcond_0($4) :
\layout Standard
-\family typewriter
+\size footnotesize
00104$:
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp13 [lr25:26]{char}[CC] = iTemp21 [lr21:38]{short}[r4] < 0xa {short}
\layout Standard
-\family typewriter
+\size footnotesize
; if iTemp13 [lr25:26]{char}[CC] == 0 goto _forbreak_0($7)
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
clr c
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov a,r4
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
xrl a,#0x80
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
subb a,#0x8a
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
jnc 00107$
\layout Standard
-\family typewriter
+\size footnotesize
00115$:
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp2 [lr18:40]{short}[r2] = iTemp2 [lr18:40]{short}[r2] +
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp21 [lr21:38]{short}[r4]
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov a,r4
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
add a,r2
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r2,a
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp15 [lr29:30]{short}[r1] = iTemp21 [lr21:38]{short}[r4] * 0x3 {short}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov b,#0x03
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov a,r4
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mul ab
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r1,a
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp11 [lr19:40]{short}[r3] = iTemp11 [lr19:40]{short}[r3] +
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp15 [lr29:30]{short}[r1]
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
add a,r3
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r3,a
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp17 [lr23:38]{int}[r7 r0]= iTemp17 [lr23:38]{int}[r7 r0]- 0x3 {short}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov a,r7
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
add a,#0xfd
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r7,a
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov a,r0
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
addc a,#0xff
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov r0,a
\layout Standard
-\family typewriter
+\size footnotesize
; _gint [lr0:0]{int} = _gint [lr0:0]{int} + iTemp17 [lr23:38]{int}[r7 r0]
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov a,r7
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
add a,_gint
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov _gint,a
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov a,r0
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
addc a,(_gint + 1)
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov (_gint + 1),a
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp21 [lr21:38]{short}[r4] = iTemp21 [lr21:38]{short}[r4] + 0x1 {short}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
inc r4
\layout Standard
-\family typewriter
+\size footnotesize
; iTemp23 [lr22:38]{int}[r5 r6]= iTemp23 [lr22:38]{int}[r5 r6]- 0x1 {short}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
dec r5
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
cjne r5,#0xff,00104$
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
dec r6
\layout Standard
-\family typewriter
+\size footnotesize
; goto _forcond_0($4)
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
sjmp 00104$
\layout Standard
-\family typewriter
+\size footnotesize
; _forbreak_0($7) :
\layout Standard
-\family typewriter
+\size footnotesize
00107$:
\layout Standard
-\family typewriter
+\size footnotesize
; ret iTemp24 [lr40:41]{short}
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov a,r3
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
add a,r2
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
mov dpl,a
\layout Standard
-\family typewriter
+\size footnotesize
; _return($8) :
\layout Standard
-\family typewriter
+\size footnotesize
00108$:
\layout Standard
-\family typewriter
+\size footnotesize
\SpecialChar ~
\SpecialChar ~
ret
-\family default
+\newline
+
+\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 Standard
+
+[basic block 1]
+\layout Standard
+
+if (something)
+\layout Standard
+
+[basic block 2]
+\layout Standard
+
+else
+\layout Standard
+
+[basic block 3]
+\layout Standard
+
+[basic block 4]
+\newline
+
+\layout Standard
+
+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