mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-29 00:01:12 +00:00
376 lines
6.4 KiB
ArmAsm
376 lines
6.4 KiB
ArmAsm
/* memchr optimized with SSE2.
|
|
Copyright (C) 2017-2023 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 <isa-level.h>
|
|
#include <sysdep.h>
|
|
|
|
/* MINIMUM_X86_ISA_LEVEL <= 2 because there is no V2 implementation
|
|
so we need this to build for ISA V2 builds. */
|
|
#if ISA_SHOULD_BUILD (2)
|
|
|
|
# ifndef MEMCHR
|
|
# define MEMCHR __memchr_sse2
|
|
# endif
|
|
# ifdef USE_AS_WMEMCHR
|
|
# define PCMPEQ pcmpeqd
|
|
# define CHAR_PER_VEC 4
|
|
# else
|
|
# define PCMPEQ pcmpeqb
|
|
# define CHAR_PER_VEC 16
|
|
# endif
|
|
|
|
/* fast SSE2 version with using pmaxub and 64 byte loop */
|
|
|
|
.text
|
|
ENTRY(MEMCHR)
|
|
movd %esi, %xmm1
|
|
mov %edi, %ecx
|
|
|
|
# ifdef __ILP32__
|
|
/* Clear the upper 32 bits. */
|
|
movl %edx, %edx
|
|
# endif
|
|
# ifdef USE_AS_WMEMCHR
|
|
test %RDX_LP, %RDX_LP
|
|
jz L(return_null)
|
|
# else
|
|
punpcklbw %xmm1, %xmm1
|
|
test %RDX_LP, %RDX_LP
|
|
jz L(return_null)
|
|
punpcklbw %xmm1, %xmm1
|
|
# endif
|
|
|
|
and $63, %ecx
|
|
pshufd $0, %xmm1, %xmm1
|
|
|
|
cmp $48, %ecx
|
|
ja L(crosscache)
|
|
|
|
movdqu (%rdi), %xmm0
|
|
PCMPEQ %xmm1, %xmm0
|
|
pmovmskb %xmm0, %eax
|
|
test %eax, %eax
|
|
|
|
jnz L(matches_1)
|
|
sub $CHAR_PER_VEC, %rdx
|
|
jbe L(return_null)
|
|
add $16, %rdi
|
|
and $15, %ecx
|
|
and $-16, %rdi
|
|
# ifdef USE_AS_WMEMCHR
|
|
shr $2, %ecx
|
|
# endif
|
|
add %rcx, %rdx
|
|
sub $(CHAR_PER_VEC * 4), %rdx
|
|
jbe L(exit_loop)
|
|
jmp L(loop_prolog)
|
|
|
|
.p2align 4
|
|
L(crosscache):
|
|
and $15, %ecx
|
|
and $-16, %rdi
|
|
movdqa (%rdi), %xmm0
|
|
|
|
PCMPEQ %xmm1, %xmm0
|
|
/* Check if there is a match. */
|
|
pmovmskb %xmm0, %eax
|
|
/* Remove the leading bytes. */
|
|
sar %cl, %eax
|
|
test %eax, %eax
|
|
je L(unaligned_no_match)
|
|
/* Check which byte is a match. */
|
|
bsf %eax, %eax
|
|
# ifdef USE_AS_WMEMCHR
|
|
mov %eax, %esi
|
|
shr $2, %esi
|
|
sub %rsi, %rdx
|
|
# else
|
|
sub %rax, %rdx
|
|
# endif
|
|
jbe L(return_null)
|
|
add %rdi, %rax
|
|
add %rcx, %rax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(unaligned_no_match):
|
|
/* "rcx" is less than 16. Calculate "rdx + rcx - 16" by using
|
|
"rdx - (16 - rcx)" instead of "(rdx + rcx) - 16" to void
|
|
possible addition overflow. */
|
|
neg %rcx
|
|
add $16, %rcx
|
|
# ifdef USE_AS_WMEMCHR
|
|
shr $2, %ecx
|
|
# endif
|
|
sub %rcx, %rdx
|
|
jbe L(return_null)
|
|
add $16, %rdi
|
|
sub $(CHAR_PER_VEC * 4), %rdx
|
|
jbe L(exit_loop)
|
|
|
|
.p2align 4
|
|
L(loop_prolog):
|
|
movdqa (%rdi), %xmm0
|
|
PCMPEQ %xmm1, %xmm0
|
|
pmovmskb %xmm0, %eax
|
|
test %eax, %eax
|
|
jnz L(matches)
|
|
|
|
movdqa 16(%rdi), %xmm2
|
|
PCMPEQ %xmm1, %xmm2
|
|
pmovmskb %xmm2, %eax
|
|
test %eax, %eax
|
|
jnz L(matches16)
|
|
|
|
movdqa 32(%rdi), %xmm3
|
|
PCMPEQ %xmm1, %xmm3
|
|
pmovmskb %xmm3, %eax
|
|
test %eax, %eax
|
|
jnz L(matches32)
|
|
|
|
movdqa 48(%rdi), %xmm4
|
|
PCMPEQ %xmm1, %xmm4
|
|
add $64, %rdi
|
|
pmovmskb %xmm4, %eax
|
|
test %eax, %eax
|
|
jnz L(matches0)
|
|
|
|
test $0x3f, %rdi
|
|
jz L(align64_loop)
|
|
|
|
sub $(CHAR_PER_VEC * 4), %rdx
|
|
jbe L(exit_loop)
|
|
|
|
movdqa (%rdi), %xmm0
|
|
PCMPEQ %xmm1, %xmm0
|
|
pmovmskb %xmm0, %eax
|
|
test %eax, %eax
|
|
jnz L(matches)
|
|
|
|
movdqa 16(%rdi), %xmm2
|
|
PCMPEQ %xmm1, %xmm2
|
|
pmovmskb %xmm2, %eax
|
|
test %eax, %eax
|
|
jnz L(matches16)
|
|
|
|
movdqa 32(%rdi), %xmm3
|
|
PCMPEQ %xmm1, %xmm3
|
|
pmovmskb %xmm3, %eax
|
|
test %eax, %eax
|
|
jnz L(matches32)
|
|
|
|
movdqa 48(%rdi), %xmm3
|
|
PCMPEQ %xmm1, %xmm3
|
|
pmovmskb %xmm3, %eax
|
|
|
|
add $64, %rdi
|
|
test %eax, %eax
|
|
jnz L(matches0)
|
|
|
|
mov %rdi, %rcx
|
|
and $-64, %rdi
|
|
and $63, %ecx
|
|
# ifdef USE_AS_WMEMCHR
|
|
shr $2, %ecx
|
|
# endif
|
|
add %rcx, %rdx
|
|
|
|
.p2align 4
|
|
L(align64_loop):
|
|
sub $(CHAR_PER_VEC * 4), %rdx
|
|
jbe L(exit_loop)
|
|
movdqa (%rdi), %xmm0
|
|
movdqa 16(%rdi), %xmm2
|
|
movdqa 32(%rdi), %xmm3
|
|
movdqa 48(%rdi), %xmm4
|
|
|
|
PCMPEQ %xmm1, %xmm0
|
|
PCMPEQ %xmm1, %xmm2
|
|
PCMPEQ %xmm1, %xmm3
|
|
PCMPEQ %xmm1, %xmm4
|
|
|
|
pmaxub %xmm0, %xmm3
|
|
pmaxub %xmm2, %xmm4
|
|
pmaxub %xmm3, %xmm4
|
|
pmovmskb %xmm4, %eax
|
|
|
|
add $64, %rdi
|
|
|
|
test %eax, %eax
|
|
jz L(align64_loop)
|
|
|
|
sub $64, %rdi
|
|
|
|
pmovmskb %xmm0, %eax
|
|
test %eax, %eax
|
|
jnz L(matches)
|
|
|
|
pmovmskb %xmm2, %eax
|
|
test %eax, %eax
|
|
jnz L(matches16)
|
|
|
|
movdqa 32(%rdi), %xmm3
|
|
PCMPEQ %xmm1, %xmm3
|
|
|
|
PCMPEQ 48(%rdi), %xmm1
|
|
pmovmskb %xmm3, %eax
|
|
test %eax, %eax
|
|
jnz L(matches32)
|
|
|
|
pmovmskb %xmm1, %eax
|
|
bsf %eax, %eax
|
|
lea 48(%rdi, %rax), %rax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(exit_loop):
|
|
add $(CHAR_PER_VEC * 2), %edx
|
|
jle L(exit_loop_32)
|
|
|
|
movdqa (%rdi), %xmm0
|
|
PCMPEQ %xmm1, %xmm0
|
|
pmovmskb %xmm0, %eax
|
|
test %eax, %eax
|
|
jnz L(matches)
|
|
|
|
movdqa 16(%rdi), %xmm2
|
|
PCMPEQ %xmm1, %xmm2
|
|
pmovmskb %xmm2, %eax
|
|
test %eax, %eax
|
|
jnz L(matches16)
|
|
|
|
movdqa 32(%rdi), %xmm3
|
|
PCMPEQ %xmm1, %xmm3
|
|
pmovmskb %xmm3, %eax
|
|
test %eax, %eax
|
|
jnz L(matches32_1)
|
|
sub $CHAR_PER_VEC, %edx
|
|
jle L(return_null)
|
|
|
|
PCMPEQ 48(%rdi), %xmm1
|
|
pmovmskb %xmm1, %eax
|
|
test %eax, %eax
|
|
jnz L(matches48_1)
|
|
xor %eax, %eax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(exit_loop_32):
|
|
add $(CHAR_PER_VEC * 2), %edx
|
|
movdqa (%rdi), %xmm0
|
|
PCMPEQ %xmm1, %xmm0
|
|
pmovmskb %xmm0, %eax
|
|
test %eax, %eax
|
|
jnz L(matches_1)
|
|
sub $CHAR_PER_VEC, %edx
|
|
jbe L(return_null)
|
|
|
|
PCMPEQ 16(%rdi), %xmm1
|
|
pmovmskb %xmm1, %eax
|
|
test %eax, %eax
|
|
jnz L(matches16_1)
|
|
xor %eax, %eax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(matches0):
|
|
bsf %eax, %eax
|
|
lea -16(%rax, %rdi), %rax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(matches):
|
|
bsf %eax, %eax
|
|
add %rdi, %rax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(matches16):
|
|
bsf %eax, %eax
|
|
lea 16(%rax, %rdi), %rax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(matches32):
|
|
bsf %eax, %eax
|
|
lea 32(%rax, %rdi), %rax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(matches_1):
|
|
bsf %eax, %eax
|
|
# ifdef USE_AS_WMEMCHR
|
|
mov %eax, %esi
|
|
shr $2, %esi
|
|
sub %rsi, %rdx
|
|
# else
|
|
sub %rax, %rdx
|
|
# endif
|
|
jbe L(return_null)
|
|
add %rdi, %rax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(matches16_1):
|
|
bsf %eax, %eax
|
|
# ifdef USE_AS_WMEMCHR
|
|
mov %eax, %esi
|
|
shr $2, %esi
|
|
sub %rsi, %rdx
|
|
# else
|
|
sub %rax, %rdx
|
|
# endif
|
|
jbe L(return_null)
|
|
lea 16(%rdi, %rax), %rax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(matches32_1):
|
|
bsf %eax, %eax
|
|
# ifdef USE_AS_WMEMCHR
|
|
mov %eax, %esi
|
|
shr $2, %esi
|
|
sub %rsi, %rdx
|
|
# else
|
|
sub %rax, %rdx
|
|
# endif
|
|
jbe L(return_null)
|
|
lea 32(%rdi, %rax), %rax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(matches48_1):
|
|
bsf %eax, %eax
|
|
# ifdef USE_AS_WMEMCHR
|
|
mov %eax, %esi
|
|
shr $2, %esi
|
|
sub %rsi, %rdx
|
|
# else
|
|
sub %rax, %rdx
|
|
# endif
|
|
jbe L(return_null)
|
|
lea 48(%rdi, %rax), %rax
|
|
ret
|
|
|
|
.p2align 4
|
|
L(return_null):
|
|
xor %eax, %eax
|
|
ret
|
|
END(MEMCHR)
|
|
#endif
|