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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)