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Also, change sources.redhat.com to sourceware.org. This patch was automatically generated by running the following shell script, which uses GNU sed, and which avoids modifying files imported from upstream: sed -ri ' s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g ' \ $(find $(git ls-files) -prune -type f \ ! -name '*.po' \ ! -name 'ChangeLog*' \ ! -path COPYING ! -path COPYING.LIB \ ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \ ! -path manual/texinfo.tex ! -path scripts/config.guess \ ! -path scripts/config.sub ! -path scripts/install-sh \ ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \ ! -path INSTALL ! -path locale/programs/charmap-kw.h \ ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \ ! '(' -name configure \ -execdir test -f configure.ac -o -f configure.in ';' ')' \ ! '(' -name preconfigure \ -execdir test -f preconfigure.ac ';' ')' \ -print) and then by running 'make dist-prepare' to regenerate files built from the altered files, and then executing the following to cleanup: chmod a+x sysdeps/unix/sysv/linux/riscv/configure # Omit irrelevant whitespace and comment-only changes, # perhaps from a slightly-different Autoconf version. git checkout -f \ sysdeps/csky/configure \ sysdeps/hppa/configure \ sysdeps/riscv/configure \ sysdeps/unix/sysv/linux/csky/configure # Omit changes that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines git checkout -f \ sysdeps/powerpc/powerpc64/ppc-mcount.S \ sysdeps/unix/sysv/linux/s390/s390-64/syscall.S # Omit change that caused a pre-commit check to fail like this: # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
106 lines
3.1 KiB
ArmAsm
106 lines
3.1 KiB
ArmAsm
/* rawmemchr -- find a byte within an unsized memory block.
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Copyright (C) 2013-2019 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library. If not, see
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<https://www.gnu.org/licenses/>. */
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#include <sysdep.h>
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.syntax unified
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.text
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ENTRY (__rawmemchr)
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@ r0 = start of string
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@ r1 = character to match
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@ returns a pointer to the match, which must be present.
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ldrb r2, [r0] @ load first byte asap
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@ To cater to long strings, we want to search through a few
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@ characters until we reach an aligned pointer. To cater to
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@ small strings, we don't want to start doing word operations
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@ immediately. The compromise is a maximum of 16 bytes less
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@ whatever is required to end with an aligned pointer.
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@ r3 = number of characters to search in alignment loop
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and r3, r0, #7
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uxtb r1, r1
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rsb r3, r3, #15 @ 16 - 1 peeled loop iteration
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cmp r2, r1
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it eq
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bxeq lr
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@ Loop until we find ...
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1: ldrb r2, [r0, #1]!
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subs r3, r3, #1 @ ... the alignment point
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it ne
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cmpne r2, r1 @ ... or C
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bne 1b
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@ Disambiguate the exit possibilites above
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cmp r2, r1 @ Found C
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it eq
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bxeq lr
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add r0, r0, #1
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@ So now we're aligned.
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ldrd r2, r3, [r0], #8
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orr r1, r1, r1, lsl #8 @ Replicate C to all bytes
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#ifdef ARCH_HAS_T2
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movw ip, #0x0101
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pld [r0, #64]
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movt ip, #0x0101
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#else
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ldr ip, =0x01010101
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pld [r0, #64]
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#endif
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orr r1, r1, r1, lsl #16
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@ Loop searching for C, 8 bytes at a time.
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@ Subtracting (unsigned saturating) from 1 means result of 1 for
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@ any byte that was originally zero and 0 otherwise. Therefore
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@ we consider the lsb of each byte the "found" bit.
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2: eor r2, r2, r1 @ Convert C bytes to 0
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eor r3, r3, r1
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uqsub8 r2, ip, r2 @ Find C
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uqsub8 r3, ip, r3
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pld [r0, #128]
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orrs r3, r3, r2 @ Test both words for found
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it eq
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ldrdeq r2, r3, [r0], #8
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beq 2b
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@ Found something. Disambiguate between first and second words.
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@ Adjust r0 to point to the word containing the match.
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@ Adjust r2 to the found bits for the word containing the match.
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cmp r2, #0
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sub r0, r0, #4
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ite eq
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moveq r2, r3
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subne r0, r0, #4
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@ Find the bit-offset of the match within the word. Note that the
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@ bit result from clz will be 7 higher than "true", but we'll
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@ immediately discard those bits converting to a byte offset.
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#ifdef __ARMEL__
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rev r2, r2 @ For LE, count from the little end
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#endif
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clz r2, r2
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add r0, r0, r2, lsr #3 @ Adjust the pointer to the found byte
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bx lr
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END (__rawmemchr)
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weak_alias (__rawmemchr, rawmemchr)
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libc_hidden_def (__rawmemchr)
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