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# strncmp()  Author: Kees J. Bot 1 Jan 1994
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/*	strncmp()					Author: Kees J. Bot */
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/*								1 Jan 1994 */
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# int strncmp(const char *s1, const char *s2, size_t ecx)
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/* int strncmp(const char *s1, const char *s2, size_t ecx) */
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#     Compare two strings.
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/*	Compare two strings. */
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#
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/* */
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.intel_syntax
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#include "asm.h"
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.globl __strncmp
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.text
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           .align  16
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ENTRY(_strncmp)
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__strncmp:
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           push    ebp
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	push	%ebp
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           mov     ebp, esp
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	movl	%esp, %ebp
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           push    esi
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	push	%esi
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           push    edi
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	push	%edi
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           test    ecx, ecx         # Max length is zero?
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	testl	%ecx, %ecx	/* Max length is zero? */
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           je      done
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	je	done
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           mov     esi, [ebp+8]     # esi = string s1
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	movl	8(%ebp), %esi	/* esi = string s1 */
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           mov     edi, [ebp+12]    # edi = string s2
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	movl	12(%ebp), %edi	/* edi = string s2 */
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           cld
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	cld
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compare:
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compare:
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           cmpsb                    # Compare two bytes
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	cmpsb	/* Compare two bytes */
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           jne     done
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	jne	done
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           cmpb    [esi-1], 0       # End of string?
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	cmpb	$0, -1(%esi)	/* End of string? */
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           je      done
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	je	done
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           dec     ecx              # Length limit reached?
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	decl	%ecx	/* Length limit reached? */
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           jne     compare
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	jne	compare
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done:
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done:
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           seta    al               # al = (s1 > s2)
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	seta	%al	/* al = (s1 > s2) */
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           setb    ah               # ah = (s1 < s2)
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	setb	%ah	/* ah = (s1 < s2) */
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           subb    al, ah
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	subb	%ah, %al
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           movsx  eax, al           # eax = (s1 > s2) - (s1 < s2), i.e. -1, 0, 1
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	movsbl	%al, %eax	/* eax = (s1 > s2) - (s1 < s2), i.e. -1, 0, 1 */
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           pop     edi
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	pop	%edi
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           pop     esi
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	pop	%esi
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           pop     ebp
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	pop	%ebp