kolibrios-gitea/drivers/ddk/string/bcmp.S

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/* bcmp() Author: Kees J. Bot */
/* 2 Jan 1994 */
/* int bcmp(const void *s1, const void *s2, size_t n) */
/* Compare two chunks of memory. */
/* This is a BSD routine that escaped from the kernel. Don't use. */
/* (Alas it is not without some use, it reports the number of bytes */
/* after the bytes that are equal. So it can't be simply replaced.) */
/* */
#include "asm.h"
ENTRY(bcmp)
push %ebp
movl %esp, %ebp
push 16(%ebp)
push 12(%ebp)
push 8(%ebp)
call _C_LABEL(memcmp) /* Let memcmp do the work */
testl %eax, %eax
je equal
subl 8(%ebp), %edx /* Memcmp was nice enough to leave "esi" in edx */
decl %edx /* Number of bytes that are equal */
movl 16(%ebp), %eax
subl %edx, %eax /* Number of bytes that are unequal */
equal:
leave
ret