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diff --git a/sysdeps/powerpc/submul_1.s b/sysdeps/powerpc/submul_1.s
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+ # Multiply a limb vector by a single limb, for PowerPC.
+ # Copyright (C) 1993, 1994, 1995, 1997 Free Software Foundation, Inc.
+ # This file is part of the GNU C Library.
+ #
+ # The GNU C Library is free software; you can redistribute it and/or
+ # modify it under the terms of the GNU Library General Public License as
+ # published by the Free Software Foundation; either version 2 of the
+ # License, or (at your option) any later version.
+ #
+ # The GNU C Library is distributed in the hope that it will be useful,
+ # but WITHOUT ANY WARRANTY; without even the implied warranty of
+ # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ # Library General Public License for more details.
+ #
+ # You should have received a copy of the GNU Library General Public
+ # License along with the GNU C Library; see the file COPYING.LIB.  If not,
+ # write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ # Boston, MA 02111-1307, USA.
+
+ # mp_limb_t mpn_submul_1 (mp_ptr res_ptr, mp_srcptr s1_ptr,
+ #                         mp_size_t s1_size, mp_limb_t s2_limb)
+ # Calculate res-s1*s2 and put result back in res; return carry.
+
+	.align 2
+	.globl __mpn_submul_1
+	.type	 __mpn_submul_1,@function
+__mpn_submul_1:
+	mtctr	%r5
+
+	lwz	%r0,0(%r4)
+	mullw	%r7,%r0,%r6
+	mulhwu	%r10,%r0,%r6
+	lwz     %r9,0(%r3)
+	subf 	%r8,%r7,%r9
+	addc    %r7,%r7,%r8		# invert cy (r7 is junk)
+	addi	%r3,%r3,-4		# adjust res_ptr
+	bdz	Lend
+
+Loop:	lwzu	%r0,4(%r4)
+	stwu	%r8,4(%r3)
+	mullw	%r8,%r0,%r6
+	adde	%r7,%r8,%r10
+	mulhwu	%r10,%r0,%r6
+	lwz     %r9,4(%r3)
+	addze   %r10,%r10
+	subf    %r8,%r7,%r9
+	addc    %r7,%r7,%r8		# invert cy (r7 is junk)
+	bdnz	Loop
+
+Lend:	stw	%r8,4(%r3)
+	addze	%r3,%r10
+	blr