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-rw-r--r--sysdeps/arm/submul_1.S74
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+/* mpn_submul_1 -- multiply and subtract bignums.
+   Copyright (C) 2013-2014 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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+
+	.syntax unified
+	.text
+
+@		cycles/limb
+@ StrongArm	   ?
+@ Cortex-A8	   ?
+@ Cortex-A9	   ?
+@ Cortex-A15	   4
+
+/* mp_limb_t mpn_submul_1(res_ptr, src1_ptr, size, s2_limb) */
+
+ENTRY (__mpn_submul_1)
+	push	{ r4, r5, r6, r7 }
+	cfi_adjust_cfa_offset (16)
+	cfi_rel_offset (r4, 0)
+	cfi_rel_offset (r5, 4)
+	cfi_rel_offset (r6, 8)
+	cfi_rel_offset (r7, 12)
+
+	sfi_breg r1, \
+	ldr	r6, [\B], #4
+	sfi_breg r0, \
+	ldr	r7, [\B]
+	mov	r4, #0			/* init carry in */
+	b	1f
+0:
+	sfi_breg r1, \
+	ldr	r6, [\B], #4		/* load next ul */
+	adds	r5, r5, r4		/* (lpl, c) = lpl + cl */
+	adc	r4, ip, #0		/* cl = hpl + c */
+	subs	r5, r7, r5		/* (lpl, !c) = rl - lpl */
+	sfi_breg r0, \
+	ldr	r7, [\B, #4]		/* load next rl */
+	it	cc
+	addcc	r4, r4, #1		/* cl += !c */
+	sfi_breg r0, \
+	str	r5, [\B], #4
+1:
+	umull	r5, ip, r6, r3		/* (hpl, lpl) = ul * vl */
+	subs	r2, r2, #1
+	bne	0b
+
+	adds	r5, r5, r4		/* (lpl, c) = lpl + cl */
+	adc	r4, ip, #0		/* cl = hpl + c */
+	subs	r5, r7, r5		/* (lpl, !c) = rl - lpl */
+	sfi_breg r0, \
+	str	r5, [\B], #4
+	it	cc
+	addcc	r4, r4, #1		/* cl += !c */
+	mov	r0, r4			/* return carry */
+
+	pop	{ r4, r5, r6, r7 }
+	DO_RET	(lr)
+END (__mpn_submul_1)