mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-15 01:21:06 +00:00
581c785bf3
I used these shell commands: ../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright (cd ../glibc && git commit -am"[this commit message]") and then ignored the output, which consisted lines saying "FOO: warning: copyright statement not found" for each of 7061 files FOO. I then removed trailing white space from math/tgmath.h, support/tst-support-open-dev-null-range.c, and sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following obscure pre-commit check failure diagnostics from Savannah. I don't know why I run into these diagnostics whereas others evidently do not. remote: *** 912-#endif remote: *** 913: remote: *** 914- remote: *** error: lines with trailing whitespace found ... remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
211 lines
4.3 KiB
ArmAsm
211 lines
4.3 KiB
ArmAsm
/* memcmp - compare memory
|
|
|
|
Copyright (C) 2013-2022 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>
|
|
|
|
/* Assumptions:
|
|
*
|
|
* ARMv8-a, AArch64, Advanced SIMD, unaligned accesses.
|
|
*/
|
|
|
|
#define src1 x0
|
|
#define src2 x1
|
|
#define limit x2
|
|
#define result w0
|
|
|
|
#define data1 x3
|
|
#define data1w w3
|
|
#define data2 x4
|
|
#define data2w w4
|
|
#define data3 x5
|
|
#define data3w w5
|
|
#define data4 x6
|
|
#define data4w w6
|
|
#define tmp x6
|
|
#define src1end x7
|
|
#define src2end x8
|
|
|
|
|
|
ENTRY (memcmp)
|
|
PTR_ARG (0)
|
|
PTR_ARG (1)
|
|
SIZE_ARG (2)
|
|
|
|
cmp limit, 16
|
|
b.lo L(less16)
|
|
ldp data1, data3, [src1]
|
|
ldp data2, data4, [src2]
|
|
ccmp data1, data2, 0, ne
|
|
ccmp data3, data4, 0, eq
|
|
b.ne L(return2)
|
|
|
|
add src1end, src1, limit
|
|
add src2end, src2, limit
|
|
cmp limit, 32
|
|
b.ls L(last_bytes)
|
|
cmp limit, 160
|
|
b.hs L(loop_align)
|
|
sub limit, limit, 32
|
|
|
|
.p2align 4
|
|
L(loop32):
|
|
ldp data1, data3, [src1, 16]
|
|
ldp data2, data4, [src2, 16]
|
|
cmp data1, data2
|
|
ccmp data3, data4, 0, eq
|
|
b.ne L(return2)
|
|
cmp limit, 16
|
|
b.ls L(last_bytes)
|
|
|
|
ldp data1, data3, [src1, 32]
|
|
ldp data2, data4, [src2, 32]
|
|
cmp data1, data2
|
|
ccmp data3, data4, 0, eq
|
|
b.ne L(return2)
|
|
add src1, src1, 32
|
|
add src2, src2, 32
|
|
L(last64):
|
|
subs limit, limit, 32
|
|
b.hi L(loop32)
|
|
|
|
/* Compare last 1-16 bytes using unaligned access. */
|
|
L(last_bytes):
|
|
ldp data1, data3, [src1end, -16]
|
|
ldp data2, data4, [src2end, -16]
|
|
L(return2):
|
|
cmp data1, data2
|
|
csel data1, data1, data3, ne
|
|
csel data2, data2, data4, ne
|
|
|
|
/* Compare data bytes and set return value to 0, -1 or 1. */
|
|
L(return):
|
|
#ifndef __AARCH64EB__
|
|
rev data1, data1
|
|
rev data2, data2
|
|
#endif
|
|
cmp data1, data2
|
|
cset result, ne
|
|
cneg result, result, lo
|
|
ret
|
|
|
|
.p2align 4
|
|
L(less16):
|
|
add src1end, src1, limit
|
|
add src2end, src2, limit
|
|
tbz limit, 3, L(less8)
|
|
ldr data1, [src1]
|
|
ldr data2, [src2]
|
|
ldr data3, [src1end, -8]
|
|
ldr data4, [src2end, -8]
|
|
b L(return2)
|
|
|
|
.p2align 4
|
|
L(less8):
|
|
tbz limit, 2, L(less4)
|
|
ldr data1w, [src1]
|
|
ldr data2w, [src2]
|
|
ldr data3w, [src1end, -4]
|
|
ldr data4w, [src2end, -4]
|
|
b L(return2)
|
|
|
|
L(less4):
|
|
tbz limit, 1, L(less2)
|
|
ldrh data1w, [src1]
|
|
ldrh data2w, [src2]
|
|
cmp data1w, data2w
|
|
b.ne L(return)
|
|
L(less2):
|
|
mov result, 0
|
|
tbz limit, 0, L(return_zero)
|
|
ldrb data1w, [src1end, -1]
|
|
ldrb data2w, [src2end, -1]
|
|
sub result, data1w, data2w
|
|
L(return_zero):
|
|
ret
|
|
|
|
L(loop_align):
|
|
ldp data1, data3, [src1, 16]
|
|
ldp data2, data4, [src2, 16]
|
|
cmp data1, data2
|
|
ccmp data3, data4, 0, eq
|
|
b.ne L(return2)
|
|
|
|
/* Align src2 and adjust src1, src2 and limit. */
|
|
and tmp, src2, 15
|
|
sub tmp, tmp, 16
|
|
sub src2, src2, tmp
|
|
add limit, limit, tmp
|
|
sub src1, src1, tmp
|
|
sub limit, limit, 64 + 16
|
|
|
|
.p2align 4
|
|
L(loop64):
|
|
ldr q0, [src1, 16]
|
|
ldr q1, [src2, 16]
|
|
subs limit, limit, 64
|
|
ldr q2, [src1, 32]
|
|
ldr q3, [src2, 32]
|
|
eor v0.16b, v0.16b, v1.16b
|
|
eor v1.16b, v2.16b, v3.16b
|
|
ldr q2, [src1, 48]
|
|
ldr q3, [src2, 48]
|
|
umaxp v0.16b, v0.16b, v1.16b
|
|
ldr q4, [src1, 64]!
|
|
ldr q5, [src2, 64]!
|
|
eor v1.16b, v2.16b, v3.16b
|
|
eor v2.16b, v4.16b, v5.16b
|
|
umaxp v1.16b, v1.16b, v2.16b
|
|
umaxp v0.16b, v0.16b, v1.16b
|
|
umaxp v0.16b, v0.16b, v0.16b
|
|
fmov tmp, d0
|
|
ccmp tmp, 0, 0, hi
|
|
b.eq L(loop64)
|
|
|
|
/* If equal, process last 1-64 bytes using scalar loop. */
|
|
add limit, limit, 64 + 16
|
|
cbz tmp, L(last64)
|
|
|
|
/* Determine the 8-byte aligned offset of the first difference. */
|
|
#ifdef __AARCH64EB__
|
|
rev16 tmp, tmp
|
|
#endif
|
|
rev tmp, tmp
|
|
clz tmp, tmp
|
|
bic tmp, tmp, 7
|
|
sub tmp, tmp, 48
|
|
ldr data1, [src1, tmp]
|
|
ldr data2, [src2, tmp]
|
|
#ifndef __AARCH64EB__
|
|
rev data1, data1
|
|
rev data2, data2
|
|
#endif
|
|
mov result, 1
|
|
cmp data1, data2
|
|
cneg result, result, lo
|
|
ret
|
|
|
|
END (memcmp)
|
|
#undef bcmp
|
|
weak_alias (memcmp, bcmp)
|
|
#undef __memcmpeq
|
|
strong_alias (memcmp, __memcmpeq)
|
|
libc_hidden_builtin_def (memcmp)
|
|
libc_hidden_def (__memcmpeq)
|