mirror/glibc
2
0
Fork 0
mirror of git://sourceware.org/git/glibc.git synced 2024-12-15 04:20:28 +08:00
Code Issues Packages Projects Releases Wiki Activity
0b5ca7c3e5
glibc/sysdeps/i386/strcspn.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

239 lines
6.6 KiB
ArmAsm
Raw Blame History

/* strcspn (str, ss) -- Return the length of the initial segment of STR
which contains no characters from SS.
For Intel 80x86, x>=3.
Copyright (C) 1994-2021 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>
#include "asm-syntax.h"
#define PARMS 4 /* no space for saved regs */
#define STR PARMS
#define STOP STR+4
.text
ENTRY (strcspn)
movl STR(%esp), %edx
movl STOP(%esp), %eax
/* First we create a table with flags for all possible characters.
For the ASCII (7bit/8bit) or ISO-8859-X character sets which are
supported by the C string functions we have 256 characters.
Before inserting marks for the stop characters we clear the whole
table. The unrolled form is much faster than a loop. */
xorl %ecx, %ecx /* %ecx = 0 !!! */
pushl %ecx /* make a 256 bytes long block filled with 0 */
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl $0 /* These immediate values make the label 2 */
cfi_adjust_cfa_offset (4)
pushl $0 /* to be aligned on a 16 byte boundary to */
cfi_adjust_cfa_offset (4)
pushl $0 /* get a better performance of the loop. */
cfi_adjust_cfa_offset (4)
pushl $0
cfi_adjust_cfa_offset (4)
pushl $0
cfi_adjust_cfa_offset (4)
pushl $0
cfi_adjust_cfa_offset (4)
/* For understanding the following code remember that %ecx == 0 now.
Although all the following instruction only modify %cl we always
have a correct zero-extended 32-bit value in %ecx. */
/* Don't change the "testb $0xff,%%cl" to "testb %%cl,%%cl". We want
longer instructions so that the next loop aligns without adding nops. */
L(2): movb (%eax), %cl /* get byte from stopset */
testb %cl, %cl /* is NUL char? */
jz L(1) /* yes => start compare loop */
movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
movb 1(%eax), %cl /* get byte from stopset */
testb $0xff, %cl /* is NUL char? */
jz L(1) /* yes => start compare loop */
movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
movb 2(%eax), %cl /* get byte from stopset */
testb $0xff, %cl /* is NUL char? */
jz L(1) /* yes => start compare loop */
movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
movb 3(%eax), %cl /* get byte from stopset */
addl $4, %eax /* increment stopset pointer */
movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
testb $0xff, %cl /* is NUL char? */
jnz L(2) /* no => process next dword from stopset */
L(1): leal -4(%edx), %eax /* prepare loop */
/* We use a neat trick for the following loop. Normally we would
have to test for two termination conditions
1. a character in the stopset was found
and
2. the end of the string was found
But as a sign that the character is in the stopset we store its
value in the table. But the value of NUL is NUL so the loop
terminates for NUL in every case. */
L(3): addl $4, %eax /* adjust pointer for full loop round */
movb (%eax), %cl /* get byte from string */
cmpb %cl, (%esp,%ecx) /* is it contained in stopset? */
je L(4) /* yes => return */
movb 1(%eax), %cl /* get byte from string */
cmpb %cl, (%esp,%ecx) /* is it contained in stopset? */
je L(5) /* yes => return */
movb 2(%eax), %cl /* get byte from string */
cmpb %cl, (%esp,%ecx) /* is it contained in stopset? */
je L(6) /* yes => return */
movb 3(%eax), %cl /* get byte from string */
cmpb %cl, (%esp,%ecx) /* is it contained in stopset? */
jne L(3) /* yes => return */
incl %eax /* adjust pointer */
L(6): incl %eax
L(5): incl %eax
L(4): addl $256, %esp /* remove stopset */
cfi_adjust_cfa_offset (-256)
subl %edx, %eax /* we have to return the number of valid
characters, so compute distance to first
non-valid character */
ret
END (strcspn)
libc_hidden_builtin_def (strcspn)
Reference in New Issue View Git Blame Copy Permalink