sys/lib/libkern/arch/amd64/strchr.S


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/*
 * Written by J.T. Conklin <jtc@netbsd.org>.
 * Public domain.
 * Adapted for NetBSD/x86_64 by Frank van der Linden <fvdl@wasabisystems.com>
 */

#include <machine/asm.h>

ENTRY(strchr)
	movq	%rdi,%rax
	movb	%sil,%cl
L1:
	movb	(%rax),%dl
	cmpb	%dl,%cl			/* found char? */
	je 	L2
	incq	%rax
	testb	%dl,%dl			/* null terminator? */
	jnz	L1
	xorq	%rax,%rax
L2:
	ret