1/* Multiply a limb vector by a single limb, for PowerPC.
2   Copyright (C) 1993-1995, 1997, 1999, 2000 Free Software Foundation, Inc.
3   This file is part of the GNU C Library.
4
5   The GNU C Library is free software; you can redistribute it and/or
6   modify it under the terms of the GNU Lesser General Public
7   License as published by the Free Software Foundation; either
8   version 2.1 of the License, or (at your option) any later version.
9
10   The GNU C Library is distributed in the hope that it will be useful,
11   but WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   Lesser General Public License for more details.
14
15   You should have received a copy of the GNU Lesser General Public
16   License along with the GNU C Library; if not, write to the Free
17   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
18   02111-1307 USA.  */
19
20#include <sysdep.h>
21#include <bp-sym.h>
22#include <bp-asm.h>
23
24/* mp_limb_t mpn_submul_1 (mp_ptr res_ptr, mp_srcptr s1_ptr,
25                           mp_size_t s1_size, mp_limb_t s2_limb)
26   Calculate res-s1*s2 and put result back in res; return carry.  */
27
28ENTRY (BP_SYM (__mpn_submul_1))
29#if __BOUNDED_POINTERS__
30	slwi r10,r5,2		/* convert limbs to bytes */
31	CHECK_BOUNDS_BOTH_WIDE (r3, r8, r9, r10)
32	CHECK_BOUNDS_BOTH_WIDE (r4, r8, r9, r10)
33#endif
34	mtctr	r5
35
36	lwz	r0,0(r4)
37	mullw	r7,r0,r6
38	mulhwu	r10,r0,r6
39	lwz     r9,0(r3)
40	subf 	r8,r7,r9
41	addc    r7,r7,r8		# invert cy (r7 is junk)
42	addi	r3,r3,-4		# adjust res_ptr
43	bdz	L(1)
44
45L(0):	lwzu	r0,4(r4)
46	stwu	r8,4(r3)
47	mullw	r8,r0,r6
48	adde	r7,r8,r10
49	mulhwu	r10,r0,r6
50	lwz     r9,4(r3)
51	addze   r10,r10
52	subf    r8,r7,r9
53	addc    r7,r7,r8		# invert cy (r7 is junk)
54	bdnz	L(0)
55
56L(1):	stw	r8,4(r3)
57	addze	r3,r10
58	blr
59END (BP_SYM (__mpn_submul_1))
60