diff options
Diffstat (limited to 'sysdeps/m68k/m68020/submul_1.S')
-rw-r--r-- | sysdeps/m68k/m68020/submul_1.S | 80 |
1 files changed, 80 insertions, 0 deletions
diff --git a/sysdeps/m68k/m68020/submul_1.S b/sysdeps/m68k/m68020/submul_1.S new file mode 100644 index 0000000..7522046 --- /dev/null +++ b/sysdeps/m68k/m68020/submul_1.S @@ -0,0 +1,80 @@ +/* mc68020 __mpn_submul_1 -- Multiply a limb vector with a limb and subtract + the result from a second limb vector. + +Copyright (C) 1992, 1994, 1996, 1998 Free Software Foundation, Inc. + +This file is part of the GNU MP Library. + +The GNU MP Library is free software; you can redistribute it and/or modify +it under the terms of the GNU Lesser General Public License as published by +the Free Software Foundation; either version 2.1 of the License, or (at your +option) any later version. + +The GNU MP 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 Lesser General Public +License for more details. + +You should have received a copy of the GNU Lesser General Public License +along with the GNU MP Library; see the file COPYING.LIB. If not, write to +the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, +MA 02111-1307, USA. */ + +/* + INPUT PARAMETERS + res_ptr (sp + 4) + s1_ptr (sp + 8) + s1_size (sp + 12) + s2_limb (sp + 16) +*/ + +#include "sysdep.h" +#include "asm-syntax.h" + + TEXT +ENTRY(__mpn_submul_1) + +#define res_ptr a0 +#define s1_ptr a1 +#define s1_size d2 +#define s2_limb d4 + +/* Save used registers on the stack. */ + moveml R(d2)-R(d5),MEM_PREDEC(sp) + +/* Copy the arguments to registers. Better use movem? */ + movel MEM_DISP(sp,20),R(res_ptr) + movel MEM_DISP(sp,24),R(s1_ptr) + movel MEM_DISP(sp,28),R(s1_size) + movel MEM_DISP(sp,32),R(s2_limb) + + eorw #1,R(s1_size) + clrl R(d1) + clrl R(d5) + lsrl #1,R(s1_size) + bcc L(L1) + subql #1,R(s1_size) + subl R(d0),R(d0) /* (d0,cy) <= (0,0) */ + +L(Loop:) + movel MEM_POSTINC(s1_ptr),R(d3) + mulul R(s2_limb),R(d1):R(d3) + addxl R(d0),R(d3) + addxl R(d5),R(d1) + subl R(d3),MEM_POSTINC(res_ptr) +L(L1:) movel MEM_POSTINC(s1_ptr),R(d3) + mulul R(s2_limb),R(d0):R(d3) + addxl R(d1),R(d3) + addxl R(d5),R(d0) + subl R(d3),MEM_POSTINC(res_ptr) + + dbf R(s1_size),L(Loop) + addxl R(d5),R(d0) + subl #0x10000,R(s1_size) + bcc L(Loop) + +/* Restore used registers from stack frame. */ + moveml MEM_POSTINC(sp),R(d2)-R(d5) + + rts +END(__mpn_submul_1) |