1 /*-------------------------------------------------------------------------
2 _mullong.c - routine for multiplication of 32 bit (unsigned) long
4 Written By - Jean Louis VERN jlvern@writeme.com (1999)
5 Written By - Sandeep Dutta . sandeep.dutta@usa.net (1999)
7 This library is free software; you can redistribute it and/or modify it
8 under the terms of the GNU Library General Public License as published by the
9 Free Software Foundation; either version 2, or (at your option) any
12 This library is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU Library General Public License for more details.
17 You should have received a copy of the GNU Library General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
21 In other words, you are welcome to use, share and improve this program.
22 You are forbidden to forbid anyone else to use, share and improve
23 what you give them. Help stamp out software-hoarding!
24 -------------------------------------------------------------------------*/
26 /* Signed and unsigned multiplication are the same - as long as the output
27 has the same precision as the input.
29 To do: _mululong and _mulslong should be replaced by _mullong.
31 bernhard@bernhardheld.de
33 Assembler-functions are provided for:
35 mcs51 small stack-auto
38 #if !defined(SDCC_USE_XSTACK) && !defined(_SDCC_NO_ASM_LIB_FUNCS)
39 # if defined(SDCC_mcs51)
40 # if defined(SDCC_MODEL_SMALL)
41 # if defined(SDCC_STACK_AUTO)
42 # define _MULLONG_ASM_SMALL_AUTO
44 # define _MULLONG_ASM_SMALL
46 # elif defined(SDCC_MODEL_LARGE)
47 # if !defined(SDCC_STACK_AUTO)
48 # define _MULLONG_ASM_LARGE
54 #if defined _MULLONG_ASM_SMALL || defined _MULLONG_ASM_SMALL_AUTO
57 _mullong_dummy (void) _naked
62 __mululong: ; obsolete
63 __mulslong: ; obsolete
66 .globl __mululong ; obsolete
67 .globl __mulslong ; obsolete
69 ; the result c will be stored in r4...r7
76 ; c1 a1 * b0 + a0 * b1
77 ; c2 a2 * b0 + a1 * b1 + a0 * b2
78 ; c3 a3 * b0 + a2 * b1 + a1 * b2 + a0 * b3
80 #if !defined SDCC_STACK_AUTO
82 #if defined(SDCC_NOOVERLAY)
89 __mululong_PARM_2: ; obsolete
90 __mulslong_PARM_2: ; obsolete
92 .globl __mullong_PARM_2
93 .globl __mululong_PARM_2 ; obsolete
94 .globl __mulslong_PARM_2 ; obsolete
100 ; parameter a comes in a, b, dph, dpl
101 mov r2,b ; save parameter a
109 b0 = __mullong_PARM_2
110 b1 = (__mullong_PARM_2+1)
111 b2 = (__mullong_PARM_2+2)
112 b3 = (__mullong_PARM_2+3)
201 #else // SDCC_STACK_AUTO
203 ; parameter a comes in a, b, dph, dpl
204 mov r2,b ; save parameter a
214 mov a,#-2-3 ; 1 return address 2 bytes, b 4 bytes
216 mov r0,a ; 1 r0 points to b0
221 mov b0,b ; we need b0 several times
222 inc r0 ; r0 points to b1
312 #endif // SDCC_STACK_AUTO
318 #elif defined _MULLONG_ASM_LARGE
321 _mullong_dummy (void) _naked
326 __mululong: ; obsolete
327 __mulslong: ; obsolete
330 .globl __mululong ; obsolete
331 .globl __mulslong ; obsolete
333 ; the result c will be stored in r4...r7
340 ; c1 a1 * b0 + a0 * b1
341 ; c2 a2 * b0 + a1 * b1 + a0 * b2
342 ; c3 a3 * b0 + a2 * b1 + a1 * b2 + a0 * b3
347 __mululong_PARM_2: ; obsolete
348 __mulslong_PARM_2: ; obsolete
350 .globl __mullong_PARM_2
351 .globl __mululong_PARM_2 ; obsolete
352 .globl __mulslong_PARM_2 ; obsolete
358 ; parameter a comes in a, b, dph, dpl
359 mov r0,dpl ; save parameter a
371 mov dptr,#__mullong_PARM_2
422 mov dptr,#__mullong_PARM_2
466 #else // _MULLONG_ASM
473 struct {unsigned char b0,b1,b2,b3 ;} b;
474 struct {unsigned int lo,hi ;} i;
476 struct { unsigned char b0; unsigned int i12; unsigned char b3;} bi;
478 #if defined(SDCC_MODEL_LARGE) || defined (SDCC_ds390)
479 #define bcast(x) ((union bil xdata *)&(x))
480 #elif defined(__z80) || defined(__gbz80)
481 #define bcast(x) ((union bil *)&(x))
483 #define bcast(x) ((union bil near *)&(x))
489 ----------------------------
494 ----------------------------
502 |-------> only this side 32 x 32 -> 32
505 _mululong (unsigned long a, unsigned long b) // in future: _mullong
509 t.i.hi = bcast(a)->b.b0 * bcast(b)->b.b2; // A
510 t.i.lo = bcast(a)->b.b0 * bcast(b)->b.b0; // A
512 t.b.b3 += bcast(a)->b.b3 *
514 t.b.b3 += bcast(a)->b.b2 *
516 t.i.hi += bcast(a)->b.b2 * bcast(b)->b.b0; // E <- b lost in .lst
517 // bcast(a)->i.hi is free !
518 t.i.hi += bcast(a)->b.b1 * bcast(b)->b.b1; // D <- b lost in .lst
520 bcast(a)->bi.b3 = bcast(a)->b.b1 *
522 bcast(a)->bi.i12 = bcast(a)->b.b1 *
525 bcast(b)->bi.b3 = bcast(a)->b.b0 *
527 bcast(b)->bi.i12 = bcast(a)->b.b0 *
529 bcast(b)->bi.b0 = 0; // B
530 bcast(a)->bi.b0 = 0; // C
537 _mulslong (long a, long b) // obsolete
539 return _mululong (a, b);
542 #endif // _MULLONG_ASM