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// SPDX-License-Identifier: GPL-2.0
#include <linux/string.h>
#include <linux/export.h>
char *strstr(const char *cs, const char *ct)
{
int d0, d1;
register char *__res;
__asm__ __volatile__(
"movl %6,%%edi\n\t"
"repne\n\t"
"scasb\n\t"
"notl %%ecx\n\t"
"decl %%ecx\n\t" /* NOTE! This also sets Z if searchstring='' */
"movl %%ecx,%%edx\n"
"1:\tmovl %6,%%edi\n\t"
"movl %%esi,%%eax\n\t"
"movl %%edx,%%ecx\n\t"
"repe\n\t"
"cmpsb\n\t"
"je 2f\n\t" /* also works for empty string, see above */
"xchgl %%eax,%%esi\n\t"
"incl %%esi\n\t"
"cmpb $0,-1(%%eax)\n\t"
"jne 1b\n\t"
"xorl %%eax,%%eax\n\t"
"2:"
: "=a" (__res), "=&c" (d0), "=&S" (d1)
: "0" (0), "1" (0xffffffff), "2" (cs), "g" (ct)
: "dx", "di");
return __res;
}
EXPORT_SYMBOL(strstr);
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