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+/* mpn_submul_1 -- multiply and subtract bignums.
+ Copyright (C) 2013 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)