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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)