glibc/sysdeps/x86_64/memchr.S
Siddhesh Poyarekar 30891f35fa Remove "Contributed by" lines
We stopped adding "Contributed by" or similar lines in sources in 2012
in favour of git logs and keeping the Contributors section of the
glibc manual up to date.  Removing these lines makes the license
header a bit more consistent across files and also removes the
possibility of error in attribution when license blocks or files are
copied across since the contributed-by lines don't actually reflect
reality in those cases.

Move all "Contributed by" and similar lines (Written by, Test by,
etc.) into a new file CONTRIBUTED-BY to retain record of these
contributions.  These contributors are also mentioned in
manual/contrib.texi, so we just maintain this additional record as a
courtesy to the earlier developers.

The following scripts were used to filter a list of files to edit in
place and to clean up the CONTRIBUTED-BY file respectively.  These
were not added to the glibc sources because they're not expected to be
of any use in future given that this is a one time task:

https://gist.github.com/siddhesh/b5ecac94eabfd72ed2916d6d8157e7dc
https://gist.github.com/siddhesh/15ea1f5e435ace9774f485030695ee02

Reviewed-by: Carlos O'Donell <carlos@redhat.com>
2021-09-03 22:06:44 +05:30

373 lines
6.3 KiB
ArmAsm

/* Copyright (C) 2011-2021 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>
#ifdef USE_AS_WMEMCHR
# define MEMCHR wmemchr
# define PCMPEQ pcmpeqd
# define CHAR_PER_VEC 4
#else
# define MEMCHR memchr
# 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)
#ifndef USE_AS_WMEMCHR
strong_alias (memchr, __memchr)
libc_hidden_builtin_def(memchr)
#endif