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diff --git a/gmp/mpn/x86/k6/divrem_1.asm b/gmp/mpn/x86/k6/divrem_1.asm
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+++ b/gmp/mpn/x86/k6/divrem_1.asm
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+dnl  AMD K6 mpn_divrem_1 -- mpn by limb division.
+
+dnl  Copyright 1999, 2000, 2001, 2002, 2003, 2007 Free Software Foundation,
+dnl  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 3 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 License
+dnl  along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.
+
+include(`../config.m4')
+
+
+C K6: 20 cycles/limb
+
+
+C mp_limb_t mpn_divrem_1 (mp_ptr dst, mp_size_t xsize,
+C                         mp_srcptr src, mp_size_t size, mp_limb_t divisor);
+C mp_limb_t mpn_divrem_1c (mp_ptr dst, mp_size_t xsize,
+C                          mp_srcptr src, mp_size_t size, mp_limb_t divisor,
+C                          mp_limb_t carry);
+C
+C The code here is basically the same as mpn/x86/divrem_1.asm, but uses loop
+C instead of decl+jnz, since it comes out 2 cycles/limb faster.
+C
+C A test is done to see if the high limb is less than the divisor, and if so
+C one less div is done.  A div is 20 cycles, so assuming high<divisor about
+C half the time, then this test saves half that amount.  The branch
+C misprediction penalty is less than that.
+C
+C Back-to-back div instructions run at 20 cycles, the same as the loop here,
+C so it seems there's nothing to gain by rearranging the loop.  Pairing the
+C mov and loop instructions was found to gain nothing.
+C
+C Enhancements:
+C
+C The low-latency K6 multiply might be thought to suit a mul-by-inverse, but
+C that algorithm has been found to suffer from the relatively poor carry
+C handling on K6 and too many auxiliary instructions.  The fractional part
+C however could be done at about 13 c/l, if it mattered enough.
+
+defframe(PARAM_CARRY,  24)
+defframe(PARAM_DIVISOR,20)
+defframe(PARAM_SIZE,   16)
+defframe(PARAM_SRC,    12)
+defframe(PARAM_XSIZE,  8)
+defframe(PARAM_DST,    4)
+
+	TEXT
+
+	ALIGN(32)
+PROLOGUE(mpn_divrem_1c)
+deflit(`FRAME',0)
+
+	movl	PARAM_SIZE, %ecx
+	pushl	%edi		FRAME_pushl()
+
+	movl	PARAM_SRC, %edi
+	pushl	%esi		FRAME_pushl()
+
+	movl	PARAM_DIVISOR, %esi
+	pushl	%ebx		FRAME_pushl()
+
+	movl	PARAM_DST, %ebx
+	pushl	%ebp		FRAME_pushl()
+
+	movl	PARAM_XSIZE, %ebp
+	orl	%ecx, %ecx		C size
+
+	movl	PARAM_CARRY, %edx
+	jz	L(fraction)		C if size==0
+
+	leal	-4(%ebx,%ebp,4), %ebx	C dst one limb below integer part
+	jmp	L(integer_top)
+
+EPILOGUE()
+
+
+	ALIGN(16)
+PROLOGUE(mpn_divrem_1)
+deflit(`FRAME',0)
+
+	movl	PARAM_SIZE, %ecx
+	pushl	%edi		FRAME_pushl()
+
+	movl	PARAM_SRC, %edi
+	pushl	%esi		FRAME_pushl()
+
+	movl	PARAM_DIVISOR, %esi
+	orl	%ecx,%ecx		C size
+
+	jz	L(size_zero)
+	pushl	%ebx		FRAME_pushl()
+
+	movl	-4(%edi,%ecx,4), %eax	C src high limb
+	xorl	%edx, %edx
+
+	movl	PARAM_DST, %ebx
+	pushl	%ebp		FRAME_pushl()
+
+	movl	PARAM_XSIZE, %ebp
+	cmpl	%esi, %eax
+
+	leal	-4(%ebx,%ebp,4), %ebx	C dst one limb below integer part
+	jae	L(integer_entry)
+
+
+	C high<divisor, so high of dst is zero, and avoid one div
+
+	movl	%edx, (%ebx,%ecx,4)
+	decl	%ecx
+
+	movl	%eax, %edx
+	jz	L(fraction)
+
+
+L(integer_top):
+	C eax	scratch (quotient)
+	C ebx	dst+4*xsize-4
+	C ecx	counter
+	C edx	scratch (remainder)
+	C esi	divisor
+	C edi	src
+	C ebp	xsize
+
+	movl	-4(%edi,%ecx,4), %eax
+L(integer_entry):
+
+	divl	%esi
+
+	movl	%eax, (%ebx,%ecx,4)
+	loop	L(integer_top)
+
+
+L(fraction):
+	orl	%ebp, %ecx
+	jz	L(done)
+
+	movl	PARAM_DST, %ebx
+
+
+L(fraction_top):
+	C eax	scratch (quotient)
+	C ebx	dst
+	C ecx	counter
+	C edx	scratch (remainder)
+	C esi	divisor
+	C edi
+	C ebp
+
+	xorl	%eax, %eax
+
+	divl	%esi
+
+	movl	%eax, -4(%ebx,%ecx,4)
+	loop	L(fraction_top)
+
+
+L(done):
+	popl	%ebp
+	movl	%edx, %eax
+	popl	%ebx
+	popl	%esi
+	popl	%edi
+	ret
+
+
+L(size_zero):
+deflit(`FRAME',8)
+	movl	PARAM_XSIZE, %ecx
+	xorl	%eax, %eax
+
+	movl	PARAM_DST, %edi
+
+	cld	C better safe than sorry, see mpn/x86/README
+
+	rep
+	stosl
+
+	popl	%esi
+	popl	%edi
+	ret
+EPILOGUE()