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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.  */
+
+#include <sysdep.h>
+
+/* 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.  */
+
+ENTRY(__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	1f
+
+0:	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	0b
+
+1:	stw	%r8,4(%r3)
+	addze	%r3,%r10
+	blr
+END(__mpn_submul_1)