* sim/ucsim/hc08.src/inst.cc,

[fw/sdcc] / device / lib / hc08 / _mulint.c

diff --git a/device/lib/hc08/_mulint.c b/device/lib/hc08/_mulint.c
new file mode 100644 (file)
index 0000000..9ac3a72
--- /dev/null
+++ b/device/lib/hc08/_mulint.c
@@ -0,0 +1,65 @@
+/*-------------------------------------------------------------------------
+  _mulint.c :- routine for (unsigned) int (16 bit) multiplication
+
+             Written By -  Sandeep Dutta . sandeep.dutta@usa.net (1999)
+
+   This library is free software; you can redistribute it and/or modify it
+   under the terms of the GNU Library General Public License as published by the
+   Free Software Foundation; either version 2, or (at your option) any
+   later version.
+
+   This library 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.  See the
+   GNU Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public License
+   along with this program; if not, write to the Free Software
+   Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+   In other words, you are welcome to use, share and improve this program.
+   You are forbidden to forbid anyone else to use, share and improve
+   what you give them.   Help stamp out software-hoarding!
+-------------------------------------------------------------------------*/
+
+/* Signed and unsigned multiplication are the same - as long as the output
+   has the same precision as the input.
+
+   Assembler-functions are provided for:
+     ds390
+     mcs51 small
+     mcs51 small stack-auto
+     mcs51 large
+*/
+
+
+union uu {
+       struct { unsigned char hi,lo ;} s;
+        unsigned int t;
+} ;
+
+int
+_mulint (int a, int b)
+{
+#if !defined(SDCC_STACK_AUTO) && (defined(SDCC_MODEL_LARGE) || defined(SDCC_ds390))    // still needed for large
+       union uu xdata *x;
+       union uu xdata *y;
+       union uu t;
+        x = (union uu xdata *)&a;
+        y = (union uu xdata *)&b;
+#else
+       register union uu *x;
+       register union uu *y;
+       union uu t;
+        x = (union uu *)&a;
+        y = (union uu *)&b;
+#endif
+
+        t.t = x->s.lo * y->s.lo;
+        t.s.hi += (x->s.lo * y->s.hi) + (x->s.hi * y->s.lo);
+
+       return t.t;
+}
+
+
+#undef _MULINT_ASM