mpir/mpn/x86/applenopic/mod_34lsub1.asm

175 lines
3.2 KiB
NASM

dnl Generic x86 mpn_mod_34lsub1 -- mpn remainder modulo 2^24-1.
dnl Copyright 2000, 2001, 2002, 2004 Free Software 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 P5: 3.0
C P6: 3.66
C K6: 3.0
C K7: 1.3
C P4: 9
C mp_limb_t mpn_mod_34lsub1 (mp_srcptr src, mp_size_t size)
C
defframe(PARAM_SIZE, 8)
defframe(PARAM_SRC, 4)
dnl re-use parameter space
define(SAVE_EBX, `PARAM_SRC')
TEXT
ALIGN(16)
PROLOGUE(mpn_mod_34lsub1)
deflit(`FRAME',0)
movl PARAM_SIZE, %ecx
movl PARAM_SRC, %edx
subl $2, %ecx
ja L(three_or_more)
movl (%edx), %eax
jb L(one)
movl 4(%edx), %ecx
movl %eax, %edx
shrl $24, %eax C src[0] low
andl $0xFFFFFF, %edx C src[0] high
addl %edx, %eax
movl %ecx, %edx
andl $0xFFFF, %ecx
shrl $16, %edx C src[1] high
addl %edx, %eax
shll $8, %ecx C src[1] low
addl %ecx, %eax
L(one):
ret
L(three_or_more):
C eax
C ebx
C ecx size-2
C edx src
C esi
C edi
C ebp
movl %ebx, SAVE_EBX C and arrange 16-byte loop alignment
xorl %ebx, %ebx
pushl %esi FRAME_pushl()
xorl %esi, %esi
pushl %edi FRAME_pushl()
xorl %eax, %eax C and clear carry flag
C offset 0x40 here
L(top):
C eax acc 0mod3
C ebx acc 1mod3
C ecx counter, limbs
C edx src
C esi acc 2mod3
C edi
C ebp
leal 12(%edx), %edx
leal -2(%ecx), %ecx
adcl -12(%edx), %eax
adcl -8(%edx), %ebx
adcl -4(%edx), %esi
decl %ecx
jg L(top)
C ecx is -2, -1 or 0 representing 0, 1 or 2 more limbs, respectively
movl $0xFFFFFFFF, %edi
incl %ecx
js L(combine)
adcl (%edx), %eax
movl $0xFFFFFF00, %edi
decl %ecx
js L(combine)
adcl 4(%edx), %ebx
movl $0xFFFF0000, %edi
L(combine):
C eax acc 0mod3
C ebx acc 1mod3
C ecx
C edx
C esi acc 2mod3
C edi mask
C ebp
sbbl %ecx, %ecx C carry
movl %eax, %edx C 0mod3
shrl $24, %eax C 0mod3 high
andl %edi, %ecx C carry masked
subl %ecx, %eax C apply carry
movl %ebx, %edi C 1mod3
shrl $16, %ebx C 1mod3 high
andl $0x00FFFFFF, %edx C 0mod3 low
addl %edx, %eax C apply 0mod3 low
andl $0xFFFF, %edi
shll $8, %edi C 1mod3 low
addl %ebx, %eax C apply 1mod3 high
addl %edi, %eax C apply 1mod3 low
movl %esi, %edx C 2mod3
shrl $8, %esi C 2mod3 high
andl $0xFF, %edx C 2mod3 low
shll $16, %edx C 2mod3 low
addl %esi, %eax C apply 2mod3 high
addl %edx, %eax C apply 2mod3 low
popl %edi FRAME_popl()
movl SAVE_EBX, %ebx
popl %esi FRAME_popl()
ret
EPILOGUE()