mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-22 13:00:06 +00:00
91 lines
2.3 KiB
ArmAsm
91 lines
2.3 KiB
ArmAsm
/* mpn_add_n -- add (or subtract) bignums.
|
|
Copyright (C) 2013-2023 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
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <sysdep.h>
|
|
#include <arm-features.h>
|
|
|
|
.syntax unified
|
|
.text
|
|
|
|
#ifdef USE_AS_SUB_N
|
|
# define INITC cmp r0, r0
|
|
# define OPC sbcs
|
|
# define RETC sbc r0, r0, r0; neg r0, r0
|
|
# define FUNC __mpn_sub_n
|
|
#else
|
|
# define INITC cmn r0, #0
|
|
# define OPC adcs
|
|
# define RETC mov r0, #0; adc r0, r0, r0
|
|
# define FUNC __mpn_add_n
|
|
#endif
|
|
|
|
/* mp_limb_t mpn_add_n(res_ptr, src1_ptr, src2_ptr, size) */
|
|
|
|
ENTRY (FUNC)
|
|
push { r4, r5, r6, r7, r8, r10, lr }
|
|
cfi_adjust_cfa_offset (28)
|
|
cfi_rel_offset (r4, 0)
|
|
cfi_rel_offset (r5, 4)
|
|
cfi_rel_offset (r6, 8)
|
|
cfi_rel_offset (r7, 12)
|
|
cfi_rel_offset (r8, 16)
|
|
cfi_rel_offset (r10, 20)
|
|
cfi_rel_offset (lr, 24)
|
|
|
|
INITC /* initialize carry flag */
|
|
tst r3, #1 /* count & 1 == 1? */
|
|
add lr, r1, r3, lsl #2 /* compute end src1 */
|
|
beq 1f
|
|
|
|
ldr r4, [r1], #4 /* do one to make count even */
|
|
ldr r5, [r2], #4
|
|
OPC r4, r4, r5
|
|
teq r1, lr /* end of count? (preserve carry) */
|
|
str r4, [r0], #4
|
|
beq 9f
|
|
1:
|
|
tst r3, #2 /* count & 2 == 2? */
|
|
beq 2f
|
|
ldm r1!, { r4, r5 } /* do two to make count 0 mod 4 */
|
|
ldm r2!, { r6, r7 }
|
|
OPC r4, r4, r6
|
|
OPC r5, r5, r7
|
|
teq r1, lr /* end of count? */
|
|
stm r0!, { r4, r5 }
|
|
beq 9f
|
|
2:
|
|
ldm r1!, { r3, r5, r7, r10 } /* do four each loop */
|
|
ldm r2!, { r4, r6, r8, ip }
|
|
OPC r3, r3, r4
|
|
OPC r5, r5, r6
|
|
OPC r7, r7, r8
|
|
OPC r10, r10, ip
|
|
teq r1, lr
|
|
stm r0!, { r3, r5, r7, r10 }
|
|
bne 2b
|
|
|
|
9:
|
|
RETC /* copy carry out */
|
|
#ifndef ARM_ALWAYS_BX
|
|
pop { r4, r5, r6, r7, r8, r10, pc }
|
|
#else
|
|
pop { r4, r5, r6, r7, r8, r10, lr }
|
|
bx lr
|
|
#endif
|
|
END (FUNC)
|