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diff --git a/ghc/rts/gmp/mpn/x86/k7/diveby3.asm b/ghc/rts/gmp/mpn/x86/k7/diveby3.asm
new file mode 100644
index 0000000..5768495
--- /dev/null
+++ b/ghc/rts/gmp/mpn/x86/k7/diveby3.asm
@@ -0,0 +1,131 @@
+dnl  AMD K7 mpn_divexact_by3 -- mpn division by 3, expecting no remainder.
+dnl 
+dnl  K7: 8.0 cycles/limb
+
+
+dnl  Copyright (C) 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 mp_limb_t mpn_divexact_by3c (mp_ptr dst, mp_srcptr src, mp_size_t size,
+C                              mp_limb_t carry);
+
+defframe(PARAM_CARRY,16)
+defframe(PARAM_SIZE, 12)
+defframe(PARAM_SRC,   8)
+defframe(PARAM_DST,   4)
+
+dnl  multiplicative inverse of 3, modulo 2^32
+deflit(INVERSE_3,        0xAAAAAAAB)
+
+dnl  ceil(b/3) and floor(b*2/3) where b=2^32
+deflit(ONE_THIRD_CEIL,   0x55555556)
+deflit(TWO_THIRDS_FLOOR, 0xAAAAAAAA)
+
+	.text
+	ALIGN(32)
+
+PROLOGUE(mpn_divexact_by3c)
+deflit(`FRAME',0)
+
+	movl	PARAM_SRC, %ecx
+	pushl	%ebx			defframe_pushl(SAVE_EBX)
+
+	movl	PARAM_CARRY, %ebx
+	pushl	%ebp			defframe_pushl(SAVE_EBP)
+
+	movl	PARAM_SIZE, %ebp
+	pushl	%edi			defframe_pushl(SAVE_EDI)
+
+	movl	(%ecx), %eax		C src low limb
+	pushl	%esi			defframe_pushl(SAVE_ESI)
+
+	movl	PARAM_DST, %edi
+	movl	$TWO_THIRDS_FLOOR, %esi
+	leal	-4(%ecx,%ebp,4), %ecx	C &src[size-1]
+
+	subl	%ebx, %eax
+
+	setc	%bl
+	decl	%ebp
+	jz	L(last)
+
+	leal	(%edi,%ebp,4), %edi	C &dst[size-1]
+	negl	%ebp
+
+
+	ALIGN(16)
+L(top):
+	C eax	src limb, carry subtracted
+	C ebx	carry limb (0 or 1)
+	C ecx	&src[size-1]
+	C edx	scratch
+	C esi	TWO_THIRDS_FLOOR
+	C edi	&dst[size-1]
+	C ebp	counter, limbs, negative
+
+	imull	$INVERSE_3, %eax, %edx
+
+	movl	4(%ecx,%ebp,4), %eax	C next src limb
+	cmpl	$ONE_THIRD_CEIL, %edx
+
+	sbbl	$-1, %ebx		C +1 if result>=ceil(b/3)
+	cmpl	%edx, %esi
+
+	sbbl	%ebx, %eax		C and further 1 if result>=ceil(b*2/3)
+	movl	%edx, (%edi,%ebp,4)
+	incl	%ebp
+
+	setc	%bl			C new carry
+	jnz	L(top)
+
+
+
+L(last):
+	C eax	src limb, carry subtracted
+	C ebx	carry limb (0 or 1)
+	C ecx	&src[size-1]
+	C edx	scratch
+	C esi	multiplier
+	C edi	&dst[size-1]
+	C ebp
+
+	imull	$INVERSE_3, %eax
+
+	cmpl	$ONE_THIRD_CEIL, %eax
+	movl	%eax, (%edi)
+	movl	SAVE_EBP, %ebp
+
+	sbbl	$-1, %ebx		C +1 if eax>=ceil(b/3)
+	cmpl	%eax, %esi
+	movl	$0, %eax
+
+	adcl	%ebx, %eax		C further +1 if eax>=ceil(b*2/3)
+	movl	SAVE_EDI, %edi
+	movl	SAVE_ESI, %esi
+
+	movl	SAVE_EBX, %ebx
+	addl	$FRAME, %esp
+
+	ret
+
+EPILOGUE()