mpir/mpn/m68k/mc68020/mul_1.asm

89 lines
2.0 KiB
NASM

dnl mc68020 mpn_mul_1 -- mpn by limb multiply
dnl Copyright 1992, 1994, 1996, 1999, 2000, 2001, 2002 Free Software
dnl Foundation, Inc.
dnl
dnl This file is part of the GNU MP Library.
dnl
dnl The GNU MP Library is free software; you can redistribute it and/or
dnl modify it under the terms of the GNU Lesser General Public License as
dnl published by the Free Software Foundation; either version 2.1 of the
dnl License, or (at your option) any later version.
dnl
dnl The GNU MP Library is distributed in the hope that it will be useful,
dnl but WITHOUT ANY WARRANTY; without even the implied warranty of
dnl MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
dnl Lesser General Public License for more details.
dnl
dnl You should have received a copy of the GNU Lesser General Public
dnl License along with the GNU MP Library; see the file COPYING.LIB. If
dnl not, write to the Free Software Foundation, Inc., 51 Franklin Street,
dnl Fifth Floor, Boston, MA 02110-1301, USA.
include(`../config.m4')
C cycles/limb
C 68040: 24
C INPUT PARAMETERS
C res_ptr (sp + 4)
C s1_ptr (sp + 8)
C s1_size (sp + 12)
C s2_limb (sp + 16)
define(res_ptr, `a0')
define(s1_ptr, `a1')
define(s1_size, `d2')
define(s2_limb, `d4')
PROLOGUE(mpn_mul_1)
C Save used registers on the stack.
moveml d2-d4, M(-,sp)
C movel d2, M(-,sp)
C movel d3, M(-,sp)
C movel d4, M(-,sp)
C Copy the arguments to registers. Better use movem?
movel M(sp,16), res_ptr
movel M(sp,20), s1_ptr
movel M(sp,24), s1_size
movel M(sp,28), s2_limb
eorw #1, s1_size
clrl d1
lsrl #1, s1_size
bcc L(L1)
subql #1, s1_size
subl d0, d0 C (d0,cy) <= (0,0)
L(Loop):
movel M(s1_ptr,+), d3
mulul s2_limb, d1:d3
addxl d0, d3
movel d3, M(res_ptr,+)
L(L1): movel M(s1_ptr,+), d3
mulul s2_limb, d0:d3
addxl d1, d3
movel d3, M(res_ptr,+)
dbf s1_size, L(Loop)
clrl d3
addxl d3, d0
subl #0x10000, s1_size
bcc L(Loop)
C Restore used registers from stack frame.
moveml M(sp,+), d2-d4
C movel M(sp,+),d4
C movel M(sp,+),d3
C movel M(sp,+),d2
rts
EPILOGUE(mpn_mul_1)