strstr_32.c 758 B

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  1. // SPDX-License-Identifier: GPL-2.0
  2. #include <linux/string.h>
  3. #include <linux/export.h>
  4. char *strstr(const char *cs, const char *ct)
  5. {
  6. int d0, d1;
  7. register char *__res;
  8. __asm__ __volatile__(
  9. "movl %6,%%edi\n\t"
  10. "repne\n\t"
  11. "scasb\n\t"
  12. "notl %%ecx\n\t"
  13. "decl %%ecx\n\t" /* NOTE! This also sets Z if searchstring='' */
  14. "movl %%ecx,%%edx\n"
  15. "1:\tmovl %6,%%edi\n\t"
  16. "movl %%esi,%%eax\n\t"
  17. "movl %%edx,%%ecx\n\t"
  18. "repe\n\t"
  19. "cmpsb\n\t"
  20. "je 2f\n\t" /* also works for empty string, see above */
  21. "xchgl %%eax,%%esi\n\t"
  22. "incl %%esi\n\t"
  23. "cmpb $0,-1(%%eax)\n\t"
  24. "jne 1b\n\t"
  25. "xorl %%eax,%%eax\n\t"
  26. "2:"
  27. : "=a" (__res), "=&c" (d0), "=&S" (d1)
  28. : "0" (0), "1" (0xffffffff), "2" (cs), "g" (ct)
  29. : "dx", "di");
  30. return __res;
  31. }
  32. EXPORT_SYMBOL(strstr);