/*-------------------------------------------------------------------------
- _divslong.c - routine for division of 32 bit signed long
+ _divslong.c - routine for division of 32 bit long
Written By - Sandeep Dutta . sandeep.dutta@usa.net (1999)
- 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
+ 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 program is distributed in the hope that it will be useful,
+
+ 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 General Public License for more details.
-
- You should have received a copy of the GNU General Public License
+ 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!
+ what you give them. Help stamp out software-hoarding!
-------------------------------------------------------------------------*/
-long _divslong (long a, long b)
+
+#include <sdcc-lib.h>
+
+#if _SDCC_MANGLES_SUPPORT_FUNS
+unsigned long _divulong (unsigned long x, unsigned long y);
+#endif
+
+/* Assembler-functions are provided for:
+ mcs51 small
+ mcs51 small stack-auto
+*/
+
+#if !defined(SDCC_USE_XSTACK) && !defined(_SDCC_NO_ASM_LIB_FUNCS)
+# if defined(SDCC_mcs51)
+# if defined(SDCC_MODEL_SMALL)
+# if defined(SDCC_STACK_AUTO) && !defined(SDCC_PARMS_IN_BANK1)
+# define _DIVSLONG_ASM_SMALL_AUTO
+# else
+# define _DIVSLONG_ASM_SMALL
+# endif
+# endif
+# endif
+#endif
+
+#if defined _DIVSLONG_ASM_SMALL
+
+static void
+_divslong_dummy (void) __naked
{
- long r;
-
- r = _divulong((a < 0 ? -a : a),
- (b < 0 ? -b : b));
- if ( (a < 0) ^ (b < 0))
- return -r;
- else
- return r;
-}
+ __asm
+
+ #define x0 dpl
+ #define x1 dph
+ #define x2 b
+ #define x3 r3
+
+ .globl __divslong
+
+ // _divslong_PARM_2 shares the same memory with _divulong_PARM_2
+ // and is defined in _divulong.c
+#if defined(SDCC_PARMS_IN_BANK1)
+ #define y0 (b1_0)
+ #define y1 (b1_1)
+ #define y2 (b1_2)
+ #define y3 (b1_3)
+#else
+ #define y0 (__divslong_PARM_2)
+ #define y1 (__divslong_PARM_2 + 1)
+ #define y2 (__divslong_PARM_2 + 2)
+ #define y3 (__divslong_PARM_2 + 3)
+#endif
+__divslong:
+ ; x3 in acc
+ ; y3 in (__divslong_PARM_2 + 3)
+ mov x3,a ; save x3
+
+ clr F0 ; Flag 0 in PSW
+ ; available to user for general purpose
+ jnb acc.7,a_not_negative
+
+ setb F0
+
+ clr a
+ clr c
+ subb a,x0
+ mov x0,a
+ clr a
+ subb a,x1
+ mov x1,a
+ clr a
+ subb a,x2
+ mov x2,a
+ clr a
+ subb a,x3
+ mov x3,a
+
+a_not_negative:
+
+ mov a,y3
+ jnb acc.7,b_not_negative
+
+ cpl F0
+
+ clr a
+ clr c
+ subb a,y0
+ mov y0,a
+ clr a
+ subb a,y1
+ mov y1,a
+ clr a
+ subb a,y2
+ mov y2,a
+ clr a
+ subb a,y3
+ mov y3,a
+
+b_not_negative:
+
+ mov a,x3 ; restore x3 in acc
+
+ lcall __divulong
+
+ jnb F0,not_negative
+
+ mov x3,a ; save x3
+
+ clr a
+ clr c
+ subb a,x0
+ mov x0,a
+ clr a
+ subb a,x1
+ mov x1,a
+ clr a
+ subb a,x2
+ mov x2,a
+ clr a
+ subb a,x3 ; x3 ends in acc
+
+not_negative:
+ ret
+
+ __endasm;
+}
+
+#elif defined _DIVSLONG_ASM_SMALL_AUTO
+
+static void
+_divslong_dummy (void) __naked
+{
+ __asm
+
+ #define x0 dpl
+ #define x1 dph
+ #define x2 b
+ #define x3 r3
+
+ .globl __divslong
+
+__divslong:
+
+ ; x3 in acc
+ mov x3,a ; save x3
+
+ clr F0 ; Flag 0 in PSW
+ ; available to user for general purpose
+ jnb acc.7,a_not_negative
+
+ setb F0
+
+ clr a
+ clr c
+ subb a,x0
+ mov x0,a
+ clr a
+ subb a,x1
+ mov x1,a
+ clr a
+ subb a,x2
+ mov x2,a
+ clr a
+ subb a,x3
+ mov x3,a
+
+a_not_negative:
+
+ mov a,sp
+ add a,#-2 ; 2 bytes return address
+ mov r0,a ; r0 points to y3
+ mov a,@r0 ; y3
+
+ jnb acc.7,b_not_negative
+
+ cpl F0
+
+ dec r0
+ dec r0
+ dec r0
+
+ clr a
+ clr c
+ subb a,@r0 ; y0
+ mov @r0,a
+ clr a
+ inc r0
+ subb a,@r0 ; y1
+ mov @r0,a
+ clr a
+ inc r0
+ subb a,@r0 ; y2
+ mov @r0,a
+ clr a
+ inc r0
+ subb a,@r0 ; y3
+ mov @r0,a
+
+b_not_negative:
+ dec r0
+ dec r0
+ dec r0 ; r0 points to y0
+
+ lcall __divlong
+
+ jnb F0,not_negative
+
+ mov x3,a ; save x3
+
+ clr a
+ clr c
+ subb a,x0
+ mov x0,a
+ clr a
+ subb a,x1
+ mov x1,a
+ clr a
+ subb a,x2
+ mov x2,a
+ clr a
+ subb a,x3 ; x3 ends in acc
+
+not_negative:
+ ret
+
+ __endasm;
+}
+
+#else // _DIVSLONG_ASM
+
+long
+_divslong (long x, long y)
+{
+ long r;
+
+ r = _divulong((x < 0 ? -x : x),
+ (y < 0 ? -y : y));
+ if ( (x < 0) ^ (y < 0))
+ return -r;
+ else
+ return r;
+}
+
+#endif // _DIVSLONG_ASM
projects / fw / sdcc / blobdiff