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-rw-r--r--arch/i386/lib/strstr.c31
1 files changed, 31 insertions, 0 deletions
diff --git a/arch/i386/lib/strstr.c b/arch/i386/lib/strstr.c
new file mode 100644
index 000000000000..a3dafbf59dae
--- /dev/null
+++ b/arch/i386/lib/strstr.c
@@ -0,0 +1,31 @@
+#include <linux/string.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;
+}
+