mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-30 08:40:07 +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
545 lines
13 KiB
ArmAsm
545 lines
13 KiB
ArmAsm
/* memcmp/wmemcmp optimized with AVX2.
|
|
Copyright (C) 2017-2022 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/>. */
|
|
|
|
#if IS_IN (libc)
|
|
|
|
/* memcmp/wmemcmp is implemented as:
|
|
1. Use ymm vector compares when possible. The only case where
|
|
vector compares is not possible for when size < VEC_SIZE
|
|
and loading from either s1 or s2 would cause a page cross.
|
|
2. For size from 2 to 7 bytes on page cross, load as big endian
|
|
with movbe and bswap to avoid branches.
|
|
3. Use xmm vector compare when size >= 4 bytes for memcmp or
|
|
size >= 8 bytes for wmemcmp.
|
|
4. Optimistically compare up to first 4 * VEC_SIZE one at a
|
|
to check for early mismatches. Only do this if its guranteed the
|
|
work is not wasted.
|
|
5. If size is 8 * VEC_SIZE or less, unroll the loop.
|
|
6. Compare 4 * VEC_SIZE at a time with the aligned first memory
|
|
area.
|
|
7. Use 2 vector compares when size is 2 * VEC_SIZE or less.
|
|
8. Use 4 vector compares when size is 4 * VEC_SIZE or less.
|
|
9. Use 8 vector compares when size is 8 * VEC_SIZE or less. */
|
|
|
|
|
|
# include <sysdep.h>
|
|
|
|
# ifndef MEMCMP
|
|
# define MEMCMP __memcmp_avx2_movbe
|
|
# endif
|
|
|
|
# ifdef USE_AS_WMEMCMP
|
|
# define CHAR_SIZE 4
|
|
# define VPCMPEQ vpcmpeqd
|
|
# else
|
|
# define CHAR_SIZE 1
|
|
# define VPCMPEQ vpcmpeqb
|
|
# endif
|
|
|
|
# ifndef VZEROUPPER
|
|
# define VZEROUPPER vzeroupper
|
|
# endif
|
|
|
|
# ifndef SECTION
|
|
# define SECTION(p) p##.avx
|
|
# endif
|
|
|
|
# define VEC_SIZE 32
|
|
# define PAGE_SIZE 4096
|
|
|
|
/* Warning!
|
|
wmemcmp has to use SIGNED comparison for elements.
|
|
memcmp has to use UNSIGNED comparison for elemnts.
|
|
*/
|
|
|
|
.section SECTION(.text),"ax",@progbits
|
|
ENTRY (MEMCMP)
|
|
# ifdef USE_AS_WMEMCMP
|
|
shl $2, %RDX_LP
|
|
# elif defined __ILP32__
|
|
/* Clear the upper 32 bits. */
|
|
movl %edx, %edx
|
|
# endif
|
|
cmp $VEC_SIZE, %RDX_LP
|
|
jb L(less_vec)
|
|
|
|
/* From VEC to 2 * VEC. No branch when size == VEC_SIZE. */
|
|
vmovdqu (%rsi), %ymm1
|
|
VPCMPEQ (%rdi), %ymm1, %ymm1
|
|
vpmovmskb %ymm1, %eax
|
|
/* NB: eax must be destination register if going to
|
|
L(return_vec_[0,2]). For L(return_vec_3 destination register
|
|
must be ecx. */
|
|
incl %eax
|
|
jnz L(return_vec_0)
|
|
|
|
cmpq $(VEC_SIZE * 2), %rdx
|
|
jbe L(last_1x_vec)
|
|
|
|
/* Check second VEC no matter what. */
|
|
vmovdqu VEC_SIZE(%rsi), %ymm2
|
|
VPCMPEQ VEC_SIZE(%rdi), %ymm2, %ymm2
|
|
vpmovmskb %ymm2, %eax
|
|
/* If all 4 VEC where equal eax will be all 1s so incl will
|
|
overflow and set zero flag. */
|
|
incl %eax
|
|
jnz L(return_vec_1)
|
|
|
|
/* Less than 4 * VEC. */
|
|
cmpq $(VEC_SIZE * 4), %rdx
|
|
jbe L(last_2x_vec)
|
|
|
|
/* Check third and fourth VEC no matter what. */
|
|
vmovdqu (VEC_SIZE * 2)(%rsi), %ymm3
|
|
VPCMPEQ (VEC_SIZE * 2)(%rdi), %ymm3, %ymm3
|
|
vpmovmskb %ymm3, %eax
|
|
incl %eax
|
|
jnz L(return_vec_2)
|
|
vmovdqu (VEC_SIZE * 3)(%rsi), %ymm4
|
|
VPCMPEQ (VEC_SIZE * 3)(%rdi), %ymm4, %ymm4
|
|
vpmovmskb %ymm4, %ecx
|
|
incl %ecx
|
|
jnz L(return_vec_3)
|
|
|
|
/* Go to 4x VEC loop. */
|
|
cmpq $(VEC_SIZE * 8), %rdx
|
|
ja L(more_8x_vec)
|
|
|
|
/* Handle remainder of size = 4 * VEC + 1 to 8 * VEC without any
|
|
branches. */
|
|
|
|
/* Load first two VEC from s2 before adjusting addresses. */
|
|
vmovdqu -(VEC_SIZE * 4)(%rsi, %rdx), %ymm1
|
|
vmovdqu -(VEC_SIZE * 3)(%rsi, %rdx), %ymm2
|
|
leaq -(4 * VEC_SIZE)(%rdi, %rdx), %rdi
|
|
leaq -(4 * VEC_SIZE)(%rsi, %rdx), %rsi
|
|
|
|
/* Wait to load from s1 until addressed adjust due to
|
|
unlamination of microfusion with complex address mode. */
|
|
VPCMPEQ (%rdi), %ymm1, %ymm1
|
|
VPCMPEQ (VEC_SIZE)(%rdi), %ymm2, %ymm2
|
|
|
|
vmovdqu (VEC_SIZE * 2)(%rsi), %ymm3
|
|
VPCMPEQ (VEC_SIZE * 2)(%rdi), %ymm3, %ymm3
|
|
vmovdqu (VEC_SIZE * 3)(%rsi), %ymm4
|
|
VPCMPEQ (VEC_SIZE * 3)(%rdi), %ymm4, %ymm4
|
|
|
|
/* Reduce VEC0 - VEC4. */
|
|
vpand %ymm1, %ymm2, %ymm5
|
|
vpand %ymm3, %ymm4, %ymm6
|
|
vpand %ymm5, %ymm6, %ymm7
|
|
vpmovmskb %ymm7, %ecx
|
|
incl %ecx
|
|
jnz L(return_vec_0_1_2_3)
|
|
/* NB: eax must be zero to reach here. */
|
|
VZEROUPPER_RETURN
|
|
|
|
.p2align 4
|
|
L(return_vec_0):
|
|
tzcntl %eax, %eax
|
|
# ifdef USE_AS_WMEMCMP
|
|
movl (%rdi, %rax), %ecx
|
|
xorl %edx, %edx
|
|
cmpl (%rsi, %rax), %ecx
|
|
/* NB: no partial register stall here because xorl zero idiom
|
|
above. */
|
|
setg %dl
|
|
leal -1(%rdx, %rdx), %eax
|
|
# else
|
|
movzbl (%rsi, %rax), %ecx
|
|
movzbl (%rdi, %rax), %eax
|
|
subl %ecx, %eax
|
|
# endif
|
|
L(return_vzeroupper):
|
|
ZERO_UPPER_VEC_REGISTERS_RETURN
|
|
|
|
.p2align 4
|
|
L(return_vec_1):
|
|
tzcntl %eax, %eax
|
|
# ifdef USE_AS_WMEMCMP
|
|
movl VEC_SIZE(%rdi, %rax), %ecx
|
|
xorl %edx, %edx
|
|
cmpl VEC_SIZE(%rsi, %rax), %ecx
|
|
setg %dl
|
|
leal -1(%rdx, %rdx), %eax
|
|
# else
|
|
movzbl VEC_SIZE(%rsi, %rax), %ecx
|
|
movzbl VEC_SIZE(%rdi, %rax), %eax
|
|
subl %ecx, %eax
|
|
# endif
|
|
VZEROUPPER_RETURN
|
|
|
|
.p2align 4
|
|
L(return_vec_2):
|
|
tzcntl %eax, %eax
|
|
# ifdef USE_AS_WMEMCMP
|
|
movl (VEC_SIZE * 2)(%rdi, %rax), %ecx
|
|
xorl %edx, %edx
|
|
cmpl (VEC_SIZE * 2)(%rsi, %rax), %ecx
|
|
setg %dl
|
|
leal -1(%rdx, %rdx), %eax
|
|
# else
|
|
movzbl (VEC_SIZE * 2)(%rsi, %rax), %ecx
|
|
movzbl (VEC_SIZE * 2)(%rdi, %rax), %eax
|
|
subl %ecx, %eax
|
|
# endif
|
|
VZEROUPPER_RETURN
|
|
|
|
/* NB: p2align 5 here to ensure 4x loop is 32 byte aligned. */
|
|
.p2align 5
|
|
L(8x_return_vec_0_1_2_3):
|
|
/* Returning from L(more_8x_vec) requires restoring rsi. */
|
|
addq %rdi, %rsi
|
|
L(return_vec_0_1_2_3):
|
|
vpmovmskb %ymm1, %eax
|
|
incl %eax
|
|
jnz L(return_vec_0)
|
|
|
|
vpmovmskb %ymm2, %eax
|
|
incl %eax
|
|
jnz L(return_vec_1)
|
|
|
|
vpmovmskb %ymm3, %eax
|
|
incl %eax
|
|
jnz L(return_vec_2)
|
|
L(return_vec_3):
|
|
tzcntl %ecx, %ecx
|
|
# ifdef USE_AS_WMEMCMP
|
|
movl (VEC_SIZE * 3)(%rdi, %rcx), %eax
|
|
xorl %edx, %edx
|
|
cmpl (VEC_SIZE * 3)(%rsi, %rcx), %eax
|
|
setg %dl
|
|
leal -1(%rdx, %rdx), %eax
|
|
# else
|
|
movzbl (VEC_SIZE * 3)(%rdi, %rcx), %eax
|
|
movzbl (VEC_SIZE * 3)(%rsi, %rcx), %ecx
|
|
subl %ecx, %eax
|
|
# endif
|
|
VZEROUPPER_RETURN
|
|
|
|
.p2align 4
|
|
L(more_8x_vec):
|
|
/* Set end of s1 in rdx. */
|
|
leaq -(VEC_SIZE * 4)(%rdi, %rdx), %rdx
|
|
/* rsi stores s2 - s1. This allows loop to only update one
|
|
pointer. */
|
|
subq %rdi, %rsi
|
|
/* Align s1 pointer. */
|
|
andq $-VEC_SIZE, %rdi
|
|
/* Adjust because first 4x vec where check already. */
|
|
subq $-(VEC_SIZE * 4), %rdi
|
|
.p2align 4
|
|
L(loop_4x_vec):
|
|
/* rsi has s2 - s1 so get correct address by adding s1 (in rdi).
|
|
*/
|
|
vmovdqu (%rsi, %rdi), %ymm1
|
|
VPCMPEQ (%rdi), %ymm1, %ymm1
|
|
|
|
vmovdqu VEC_SIZE(%rsi, %rdi), %ymm2
|
|
VPCMPEQ VEC_SIZE(%rdi), %ymm2, %ymm2
|
|
|
|
vmovdqu (VEC_SIZE * 2)(%rsi, %rdi), %ymm3
|
|
VPCMPEQ (VEC_SIZE * 2)(%rdi), %ymm3, %ymm3
|
|
|
|
vmovdqu (VEC_SIZE * 3)(%rsi, %rdi), %ymm4
|
|
VPCMPEQ (VEC_SIZE * 3)(%rdi), %ymm4, %ymm4
|
|
|
|
vpand %ymm1, %ymm2, %ymm5
|
|
vpand %ymm3, %ymm4, %ymm6
|
|
vpand %ymm5, %ymm6, %ymm7
|
|
vpmovmskb %ymm7, %ecx
|
|
incl %ecx
|
|
jnz L(8x_return_vec_0_1_2_3)
|
|
subq $-(VEC_SIZE * 4), %rdi
|
|
/* Check if s1 pointer at end. */
|
|
cmpq %rdx, %rdi
|
|
jb L(loop_4x_vec)
|
|
|
|
subq %rdx, %rdi
|
|
/* rdi has 4 * VEC_SIZE - remaining length. */
|
|
cmpl $(VEC_SIZE * 3), %edi
|
|
jae L(8x_last_1x_vec)
|
|
/* Load regardless of branch. */
|
|
vmovdqu (VEC_SIZE * 2)(%rsi, %rdx), %ymm3
|
|
cmpl $(VEC_SIZE * 2), %edi
|
|
jae L(8x_last_2x_vec)
|
|
|
|
/* Check last 4 VEC. */
|
|
vmovdqu (%rsi, %rdx), %ymm1
|
|
VPCMPEQ (%rdx), %ymm1, %ymm1
|
|
|
|
vmovdqu VEC_SIZE(%rsi, %rdx), %ymm2
|
|
VPCMPEQ VEC_SIZE(%rdx), %ymm2, %ymm2
|
|
|
|
VPCMPEQ (VEC_SIZE * 2)(%rdx), %ymm3, %ymm3
|
|
|
|
vmovdqu (VEC_SIZE * 3)(%rsi, %rdx), %ymm4
|
|
VPCMPEQ (VEC_SIZE * 3)(%rdx), %ymm4, %ymm4
|
|
|
|
vpand %ymm1, %ymm2, %ymm5
|
|
vpand %ymm3, %ymm4, %ymm6
|
|
vpand %ymm5, %ymm6, %ymm7
|
|
vpmovmskb %ymm7, %ecx
|
|
/* Restore s1 pointer to rdi. */
|
|
movq %rdx, %rdi
|
|
incl %ecx
|
|
jnz L(8x_return_vec_0_1_2_3)
|
|
/* NB: eax must be zero to reach here. */
|
|
VZEROUPPER_RETURN
|
|
|
|
/* Only entry is from L(more_8x_vec). */
|
|
.p2align 4
|
|
L(8x_last_2x_vec):
|
|
/* Check second to last VEC. rdx store end pointer of s1 and
|
|
ymm3 has already been loaded with second to last VEC from s2.
|
|
*/
|
|
VPCMPEQ (VEC_SIZE * 2)(%rdx), %ymm3, %ymm3
|
|
vpmovmskb %ymm3, %eax
|
|
incl %eax
|
|
jnz L(8x_return_vec_2)
|
|
/* Check last VEC. */
|
|
.p2align 4
|
|
L(8x_last_1x_vec):
|
|
vmovdqu (VEC_SIZE * 3)(%rsi, %rdx), %ymm4
|
|
VPCMPEQ (VEC_SIZE * 3)(%rdx), %ymm4, %ymm4
|
|
vpmovmskb %ymm4, %eax
|
|
incl %eax
|
|
jnz L(8x_return_vec_3)
|
|
VZEROUPPER_RETURN
|
|
|
|
.p2align 4
|
|
L(last_2x_vec):
|
|
/* Check second to last VEC. */
|
|
vmovdqu -(VEC_SIZE * 2)(%rsi, %rdx), %ymm1
|
|
VPCMPEQ -(VEC_SIZE * 2)(%rdi, %rdx), %ymm1, %ymm1
|
|
vpmovmskb %ymm1, %eax
|
|
incl %eax
|
|
jnz L(return_vec_1_end)
|
|
/* Check last VEC. */
|
|
L(last_1x_vec):
|
|
vmovdqu -(VEC_SIZE * 1)(%rsi, %rdx), %ymm1
|
|
VPCMPEQ -(VEC_SIZE * 1)(%rdi, %rdx), %ymm1, %ymm1
|
|
vpmovmskb %ymm1, %eax
|
|
incl %eax
|
|
jnz L(return_vec_0_end)
|
|
VZEROUPPER_RETURN
|
|
|
|
.p2align 4
|
|
L(8x_return_vec_2):
|
|
subq $VEC_SIZE, %rdx
|
|
L(8x_return_vec_3):
|
|
tzcntl %eax, %eax
|
|
addq %rdx, %rax
|
|
# ifdef USE_AS_WMEMCMP
|
|
movl (VEC_SIZE * 3)(%rax), %ecx
|
|
xorl %edx, %edx
|
|
cmpl (VEC_SIZE * 3)(%rsi, %rax), %ecx
|
|
setg %dl
|
|
leal -1(%rdx, %rdx), %eax
|
|
# else
|
|
movzbl (VEC_SIZE * 3)(%rsi, %rax), %ecx
|
|
movzbl (VEC_SIZE * 3)(%rax), %eax
|
|
subl %ecx, %eax
|
|
# endif
|
|
VZEROUPPER_RETURN
|
|
|
|
.p2align 4
|
|
L(return_vec_1_end):
|
|
tzcntl %eax, %eax
|
|
addl %edx, %eax
|
|
# ifdef USE_AS_WMEMCMP
|
|
movl -(VEC_SIZE * 2)(%rdi, %rax), %ecx
|
|
xorl %edx, %edx
|
|
cmpl -(VEC_SIZE * 2)(%rsi, %rax), %ecx
|
|
setg %dl
|
|
leal -1(%rdx, %rdx), %eax
|
|
# else
|
|
movzbl -(VEC_SIZE * 2)(%rsi, %rax), %ecx
|
|
movzbl -(VEC_SIZE * 2)(%rdi, %rax), %eax
|
|
subl %ecx, %eax
|
|
# endif
|
|
VZEROUPPER_RETURN
|
|
|
|
.p2align 4
|
|
L(return_vec_0_end):
|
|
tzcntl %eax, %eax
|
|
addl %edx, %eax
|
|
# ifdef USE_AS_WMEMCMP
|
|
movl -VEC_SIZE(%rdi, %rax), %ecx
|
|
xorl %edx, %edx
|
|
cmpl -VEC_SIZE(%rsi, %rax), %ecx
|
|
setg %dl
|
|
leal -1(%rdx, %rdx), %eax
|
|
# else
|
|
movzbl -VEC_SIZE(%rsi, %rax), %ecx
|
|
movzbl -VEC_SIZE(%rdi, %rax), %eax
|
|
subl %ecx, %eax
|
|
# endif
|
|
VZEROUPPER_RETURN
|
|
|
|
.p2align 4
|
|
L(less_vec):
|
|
/* Check if one or less CHAR. This is necessary for size = 0 but
|
|
is also faster for size = CHAR_SIZE. */
|
|
cmpl $CHAR_SIZE, %edx
|
|
jbe L(one_or_less)
|
|
|
|
/* Check if loading one VEC from either s1 or s2 could cause a
|
|
page cross. This can have false positives but is by far the
|
|
fastest method. */
|
|
movl %edi, %eax
|
|
orl %esi, %eax
|
|
andl $(PAGE_SIZE - 1), %eax
|
|
cmpl $(PAGE_SIZE - VEC_SIZE), %eax
|
|
jg L(page_cross_less_vec)
|
|
|
|
/* No page cross possible. */
|
|
vmovdqu (%rsi), %ymm2
|
|
VPCMPEQ (%rdi), %ymm2, %ymm2
|
|
vpmovmskb %ymm2, %eax
|
|
incl %eax
|
|
/* Result will be zero if s1 and s2 match. Otherwise first set
|
|
bit will be first mismatch. */
|
|
bzhil %edx, %eax, %edx
|
|
jnz L(return_vec_0)
|
|
xorl %eax, %eax
|
|
VZEROUPPER_RETURN
|
|
|
|
.p2align 4
|
|
L(page_cross_less_vec):
|
|
/* if USE_AS_WMEMCMP it can only be 0, 4, 8, 12, 16, 20, 24, 28
|
|
bytes. */
|
|
cmpl $16, %edx
|
|
jae L(between_16_31)
|
|
# ifndef USE_AS_WMEMCMP
|
|
cmpl $8, %edx
|
|
jae L(between_8_15)
|
|
cmpl $4, %edx
|
|
jae L(between_4_7)
|
|
|
|
/* Load as big endian to avoid branches. */
|
|
movzwl (%rdi), %eax
|
|
movzwl (%rsi), %ecx
|
|
shll $8, %eax
|
|
shll $8, %ecx
|
|
bswap %eax
|
|
bswap %ecx
|
|
movzbl -1(%rdi, %rdx), %edi
|
|
movzbl -1(%rsi, %rdx), %esi
|
|
orl %edi, %eax
|
|
orl %esi, %ecx
|
|
/* Subtraction is okay because the upper 8 bits are zero. */
|
|
subl %ecx, %eax
|
|
/* No ymm register was touched. */
|
|
ret
|
|
|
|
.p2align 4
|
|
L(one_or_less):
|
|
jb L(zero)
|
|
movzbl (%rsi), %ecx
|
|
movzbl (%rdi), %eax
|
|
subl %ecx, %eax
|
|
/* No ymm register was touched. */
|
|
ret
|
|
|
|
.p2align 4
|
|
L(between_8_15):
|
|
# endif
|
|
/* If USE_AS_WMEMCMP fall through into 8-15 byte case. */
|
|
vmovq (%rdi), %xmm1
|
|
vmovq (%rsi), %xmm2
|
|
VPCMPEQ %xmm1, %xmm2, %xmm2
|
|
vpmovmskb %xmm2, %eax
|
|
subl $0xffff, %eax
|
|
jnz L(return_vec_0)
|
|
/* Use overlapping loads to avoid branches. */
|
|
leaq -8(%rdi, %rdx), %rdi
|
|
leaq -8(%rsi, %rdx), %rsi
|
|
vmovq (%rdi), %xmm1
|
|
vmovq (%rsi), %xmm2
|
|
VPCMPEQ %xmm1, %xmm2, %xmm2
|
|
vpmovmskb %xmm2, %eax
|
|
subl $0xffff, %eax
|
|
jnz L(return_vec_0)
|
|
/* No ymm register was touched. */
|
|
ret
|
|
|
|
.p2align 4
|
|
L(zero):
|
|
xorl %eax, %eax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(between_16_31):
|
|
/* From 16 to 31 bytes. No branch when size == 16. */
|
|
vmovdqu (%rsi), %xmm2
|
|
VPCMPEQ (%rdi), %xmm2, %xmm2
|
|
vpmovmskb %xmm2, %eax
|
|
subl $0xffff, %eax
|
|
jnz L(return_vec_0)
|
|
|
|
/* Use overlapping loads to avoid branches. */
|
|
|
|
vmovdqu -16(%rsi, %rdx), %xmm2
|
|
leaq -16(%rdi, %rdx), %rdi
|
|
leaq -16(%rsi, %rdx), %rsi
|
|
VPCMPEQ (%rdi), %xmm2, %xmm2
|
|
vpmovmskb %xmm2, %eax
|
|
subl $0xffff, %eax
|
|
jnz L(return_vec_0)
|
|
/* No ymm register was touched. */
|
|
ret
|
|
|
|
# ifdef USE_AS_WMEMCMP
|
|
.p2align 4
|
|
L(one_or_less):
|
|
jb L(zero)
|
|
movl (%rdi), %ecx
|
|
xorl %edx, %edx
|
|
cmpl (%rsi), %ecx
|
|
je L(zero)
|
|
setg %dl
|
|
leal -1(%rdx, %rdx), %eax
|
|
/* No ymm register was touched. */
|
|
ret
|
|
# else
|
|
|
|
.p2align 4
|
|
L(between_4_7):
|
|
/* Load as big endian with overlapping movbe to avoid branches.
|
|
*/
|
|
movbe (%rdi), %eax
|
|
movbe (%rsi), %ecx
|
|
shlq $32, %rax
|
|
shlq $32, %rcx
|
|
movbe -4(%rdi, %rdx), %edi
|
|
movbe -4(%rsi, %rdx), %esi
|
|
orq %rdi, %rax
|
|
orq %rsi, %rcx
|
|
subq %rcx, %rax
|
|
jz L(zero_4_7)
|
|
sbbl %eax, %eax
|
|
orl $1, %eax
|
|
L(zero_4_7):
|
|
/* No ymm register was touched. */
|
|
ret
|
|
# endif
|
|
|
|
END (MEMCMP)
|
|
#endif
|