mpir/mpn/x86/k7/mmx/copyd.asm
2008-04-17 21:03:07 +00:00

136 lines
2.8 KiB
NASM

dnl AMD K7 mpn_copyd -- copy limb vector, decrementing.
dnl Copyright 1999, 2000, 2002 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 alignment dst/src, A=0mod8 N=4mod8
C A/A A/N N/A N/N
C K7 0.75 1.0 1.0 0.75
C void mpn_copyd (mp_ptr dst, mp_srcptr src, mp_size_t size);
C
C The various comments in mpn/x86/k7/copyi.asm apply here too.
defframe(PARAM_SIZE,12)
defframe(PARAM_SRC, 8)
defframe(PARAM_DST, 4)
deflit(`FRAME',0)
dnl parameter space reused
define(SAVE_EBX,`PARAM_SIZE')
define(SAVE_ESI,`PARAM_SRC')
dnl minimum 5 since the unrolled code can't handle less than 5
deflit(UNROLL_THRESHOLD, 5)
TEXT
ALIGN(32)
PROLOGUE(mpn_copyd)
movl PARAM_SIZE, %ecx
movl %ebx, SAVE_EBX
movl PARAM_SRC, %eax
movl PARAM_DST, %edx
cmpl $UNROLL_THRESHOLD, %ecx
jae L(unroll)
orl %ecx, %ecx
jz L(simple_done)
L(simple):
C eax src
C ebx scratch
C ecx counter
C edx dst
C
C this loop is 2 cycles/limb
movl -4(%eax,%ecx,4), %ebx
movl %ebx, -4(%edx,%ecx,4)
decl %ecx
jnz L(simple)
L(simple_done):
movl SAVE_EBX, %ebx
ret
L(unroll):
movl %esi, SAVE_ESI
leal (%eax,%ecx,4), %ebx
leal (%edx,%ecx,4), %esi
andl %esi, %ebx
movl SAVE_ESI, %esi
subl $4, %ecx C size-4
testl $4, %ebx C testl to pad code closer to 16 bytes for L(top)
jz L(aligned)
C both src and dst unaligned, process one limb to align them
movl 12(%eax,%ecx,4), %ebx
movl %ebx, 12(%edx,%ecx,4)
decl %ecx
L(aligned):
ALIGN(16)
L(top):
C eax src
C ebx
C ecx counter, limbs
C edx dst
movq 8(%eax,%ecx,4), %mm0
movq (%eax,%ecx,4), %mm1
subl $4, %ecx
movq %mm0, 16+8(%edx,%ecx,4)
movq %mm1, 16(%edx,%ecx,4)
jns L(top)
C now %ecx is -4 to -1 representing respectively 0 to 3 limbs remaining
testb $2, %cl
jz L(finish_not_two)
movq 8(%eax,%ecx,4), %mm0
movq %mm0, 8(%edx,%ecx,4)
L(finish_not_two):
testb $1, %cl
jz L(done)
movl (%eax), %ebx
movl %ebx, (%edx)
L(done):
movl SAVE_EBX, %ebx
emms
ret
EPILOGUE()