* mpn/x86/k7/mod_34lsub1.asm: New file.

1 files changed, 179 insertions, 0 deletions

diff --git a/mpn/x86/k7/mod_34lsub1.asm b/mpn/x86/k7/mod_34lsub1.asm
new file mode 100644
index 000000000..22a335a7d
--- /dev/null
+++ b/mpn/x86/k7/mod_34lsub1.asm
@@ -0,0 +1,179 @@
+dnl  AMD K7 mpn_mod_32lsub1 -- remainder modulo 2^24-1.
+dnl
+dnl  K7: 1.0 cycles/limb
+
+dnl  Copyright 2000, 2001 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 mp_limb_t mpn_mod_34lsub1 (mp_srcptr src, mp_size_t size)
+C
+C The loop form below and the 64 byte code alignment seem necessary for the
+C claimed speed.  This is a bit strange, since normally k7 isn't very
+C sensitive to such things.  Perhaps there has to be 6 instructions in the
+C first 16 bytes for the BTB entry or something.
+
+defframe(PARAM_SIZE, 8)
+defframe(PARAM_SRC,  4)
+
+dnl  re-use parameter space
+define(SAVE_EDI, `PARAM_SIZE')
+
+	TEXT
+	ALIGN(64)
+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
+
+	pushl	%ebx	FRAME_pushl()
+	xorl	%eax, %eax
+	xorl	%ebx, %ebx
+
+	movl	%edi, SAVE_EDI
+	pushl	%esi	FRAME_pushl()
+	xorl	%esi, %esi		C and clear carry flag
+
+
+	C code offset 0x40 at this point
+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	24(%edx), %edx
+	leal	-2(%ecx), %ecx
+	adcl	-24(%edx), %eax
+	adcl	-20(%edx), %ebx
+	adcl	-16(%edx), %esi
+
+ 	decl	%ecx
+ 	jng	L(done_loop)
+
+	leal	-2(%ecx), %ecx
+	adcl	-12(%edx), %eax
+	adcl	-8(%edx), %ebx
+	adcl	-4(%edx), %esi
+
+	decl	%ecx
+	jg	L(top)
+
+
+	leal	12(%edx), %edx
+
+
+L(done_loop):
+	C ecx is -2, -1 or 0 representing 0, 1 or 2 more limbs, respectively
+
+	incl	%ecx
+	movl	$0xFFFFFFFF, %edi
+	js	L(combine)
+
+	adcl	-12(%edx), %eax
+	decl	%ecx
+	movl	$0xFFFFFF00, %edi
+	js	L(combine)
+
+	adcl	-8(%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
+	andl	$0x00FFFFFF, %edx	C 0mod3 low
+	movl	%ebx, %edi		C 1mod3
+
+	subl	%ecx, %eax		C apply carry
+	shrl	$16, %ebx		C 1mod3 high
+	andl	$0xFFFF, %edi
+
+	addl	%edx, %eax		C apply 0mod3 low
+	movl	%esi, %edx		C 2mod3
+	shll	$8, %edi		C 1mod3 low
+
+	addl	%ebx, %eax		C apply 1mod3 high
+	shrl	$8, %esi		C 2mod3 high
+	andl	$0xFF, %edx		C 2mod3 low
+
+	addl	%edi, %eax		C apply 1mod3 low
+	shll	$16, %edx		C 2mod3 low
+
+	addl	%esi, %eax		C apply 2mod3 high
+	popl	%esi	FRAME_popl()
+
+	movl	SAVE_EDI, %edi
+	addl	%edx, %eax		C apply 2mod3 low
+	popl	%ebx	FRAME_popl()
+
+	ret
+
+EPILOGUE()