glibc/sysdeps/i386/stpcpy.S
Paul Eggert 5a82c74822 Prefer https to http for gnu.org and fsf.org URLs
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
2019-09-07 02:43:31 -07:00

89 lines
2.7 KiB
ArmAsm

/* Copy SRC to DEST returning the address of the terminating '\0' in DEST.
For Intel 80x86, x>=3.
Copyright (C) 1994-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper (drepper@gnu.ai.mit.edu).
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/>. */
/* This function is defined neither in ANSI nor POSIX standards but is
also not invented here. */
#include <sysdep.h>
#include "asm-syntax.h"
#define PARMS 4 /* no space for saved regs */
#define RTN PARMS
#define DEST RTN
#define SRC DEST+4
.text
ENTRY (__stpcpy)
movl DEST(%esp), %eax
movl SRC(%esp), %ecx
subl %eax, %ecx /* magic: reduce number of loop variants
to one using addressing mode */
/* Here we would like to write
subl $4, %eax
ALIGN (4)
but the assembler is too smart and optimizes for the shortest
form where the number only needs one byte. But if we could
have the long form we would not need the alignment. */
.byte 0x81, 0xe8 /* This is `subl $0x00000004, %eax' */
.long 0x00000004
/* Four times unfolded loop with only one loop counter. This
is achieved by the use of index+base addressing mode. As the
loop counter we use the destination address because this is
also the result. */
L(1): addl $4, %eax /* increment loop counter */
movb (%eax,%ecx), %dl /* load current char */
movb %dl, (%eax) /* and store it */
testb %dl, %dl /* was it NUL? */
jz L(2) /* yes, then exit */
movb 1(%eax,%ecx), %dl /* load current char */
movb %dl, 1(%eax) /* and store it */
testb %dl, %dl /* was it NUL? */
jz L(3) /* yes, then exit */
movb 2(%eax,%ecx), %dl /* load current char */
movb %dl, 2(%eax) /* and store it */
testb %dl, %dl /* was it NUL? */
jz L(4) /* yes, then exit */
movb 3(%eax,%ecx), %dl /* load current char */
movb %dl, 3(%eax) /* and store it */
testb %dl, %dl /* was it NUL? */
jnz L(1) /* no, then continue loop */
incl %eax /* correct loop counter */
L(4): incl %eax
L(3): incl %eax
L(2):
ret
END (__stpcpy)
weak_alias (__stpcpy, stpcpy)
libc_hidden_def (__stpcpy)
libc_hidden_builtin_def (stpcpy)