--- /dev/null
+dnl AMD K7 mpn_copyd -- copy limb vector, decrementing.
+dnl
+dnl alignment dst/src, A=0mod8 N=4mod8
+dnl A/A A/N N/A N/N
+dnl K7 0.75 1.0 1.0 0.75
+
+
+dnl Copyright (C) 1999, 2000 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., 59 Temple Place -
+dnl Suite 330, Boston, MA 02111-1307, USA.
+
+
+include(`../config.m4')
+
+
+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()