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/* strcspn (str, ss) -- Return the length of the initial segment of STR
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			which contains only characters from SS.
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   For Intel 80x86, x>=3.
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   Copyright (C) 1994-2018 Free Software Foundation, Inc.
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   This file is part of the GNU C Library.
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   Contributed by Ulrich Drepper <drepper@gnu.ai.mit.edu>
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   Bug fixes by Alan Modra <Alan@SPRI.Levels.UniSA.Edu.Au>
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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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   <http://www.gnu.org/licenses/>.  */
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#include <sysdep.h>
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#include "asm-syntax.h"
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#define PARMS	4		/* no space for saved regs */
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#define STR	PARMS
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#define SKIP	STR+4
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	.text
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ENTRY (strspn)
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	movl STR(%esp), %edx
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	movl SKIP(%esp), %eax
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	/* First we create a table with flags for all possible characters.
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	   For the ASCII (7bit/8bit) or ISO-8859-X character sets which are
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	   supported by the C string functions we have 256 characters.
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	   Before inserting marks for the stop characters we clear the whole
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	   table.  The unrolled form is much faster than a loop.  */
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	xorl %ecx, %ecx		/* %ecx = 0 !!! */
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	pushl %ecx		/* make a 256 bytes long block filled with 0 */
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl %ecx
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	cfi_adjust_cfa_offset (4)
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	pushl $0		/* These immediate values make the label 2 */
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	cfi_adjust_cfa_offset (4)
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	pushl $0		/* to be aligned on a 16 byte boundary to */
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	cfi_adjust_cfa_offset (4)
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	pushl $0		/* get a better performance of the loop.  */
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	cfi_adjust_cfa_offset (4)
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	pushl $0
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	cfi_adjust_cfa_offset (4)
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	pushl $0
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	cfi_adjust_cfa_offset (4)
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	pushl $0
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	cfi_adjust_cfa_offset (4)
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/* For understanding the following code remember that %ecx == 0 now.
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   Although all the following instruction only modify %cl we always
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   have a correct zero-extended 32-bit value in %ecx.  */
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/* Don't change the "testb $0xff,%%cl" to "testb %%cl,%%cl".  We want
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   longer instructions so that the next loop aligns without adding nops.  */
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L(2):	movb (%eax), %cl	/* get byte from stopset */
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	testb %cl, %cl		/* is NUL char? */
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	jz L(1)			/* yes => start compare loop */
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	movb %cl, (%esp,%ecx)	/* set corresponding byte in stopset table */
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	movb 1(%eax), %cl	/* get byte from stopset */
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	testb $0xff, %cl	/* is NUL char? */
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	jz L(1)			/* yes => start compare loop */
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	movb %cl, (%esp,%ecx)	/* set corresponding byte in stopset table */
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	movb 2(%eax), %cl	/* get byte from stopset */
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	testb $0xff, %cl	/* is NUL char? */
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	jz L(1)			/* yes => start compare loop */
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	movb %cl, (%esp,%ecx)	/* set corresponding byte in stopset table */
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	movb 3(%eax), %cl	/* get byte from stopset */
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	addl $4, %eax		/* increment stopset pointer */
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	movb %cl, (%esp,%ecx)	/* set corresponding byte in stopset table */
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	testb $0xff, %cl	/* is NUL char? */
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	jnz L(2)		/* no => process next dword from stopset */
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L(1):	leal -4(%edx), %eax	/* prepare loop */
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	/* We use a neat trick for the following loop.  Normally we would
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	   have to test for two termination conditions
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	   1. a character in the stopset was found
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	   and
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	   2. the end of the string was found
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	   But as a sign that the character is in the stopset we store its
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	   value in the table.  But the value of NUL is NUL so the loop
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	   terminates for NUL in every case.  */
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L(3):	addl $4, %eax		/* adjust pointer for full loop round */
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	movb (%eax), %cl	/* get byte from string */
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	testb %cl, (%esp,%ecx)	/* is it contained in skipset? */
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	jz L(4)			/* no => return */
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	movb 1(%eax), %cl	/* get byte from string */
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	testb %cl, (%esp,%ecx)	/* is it contained in skipset? */
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	jz L(5)			/* no => return */
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	movb 2(%eax), %cl	/* get byte from string */
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	testb %cl, (%esp,%ecx)	/* is it contained in skipset? */
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	jz L(6)			/* no => return */
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	movb 3(%eax), %cl	/* get byte from string */
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	testb %cl, (%esp,%ecx)	/* is it contained in skipset? */
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	jnz L(3)		/* yes => start loop again */
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	incl %eax		/* adjust pointer */
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L(6):	incl %eax
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L(5):	incl %eax
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L(4):	addl $256, %esp		/* remove stopset */
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	cfi_adjust_cfa_offset (-256)
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	subl %edx, %eax		/* we have to return the number of valid
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				   characters, so compute distance to first
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				   non-valid character */
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	ret
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END (strspn)
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libc_hidden_builtin_def (strspn)

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