testsuite: Add testcases for already fixed PR [PR93927]

2020-03-03  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/93927
	* gcc.c-torture/compile/pr93927-1.c: New test.
	* gcc.c-torture/compile/pr93927-2.c: New test.

gcc/testsuite/ChangeLog

+2020-03-03  Jakub Jelinek  <jakub@redhat.com>
+
+	PR tree-optimization/93927
+	* gcc.c-torture/compile/pr93927-1.c: New test.
+	* gcc.c-torture/compile/pr93927-2.c: New test.
+
 2020-03-03  Jun Ma <JunMa@linux.alibaba.com>
 
 	* g++.dg/coroutines/torture/co-await-14-template-traits.C: New test.

gcc/testsuite/gcc.c-torture/compile/pr93927-1.c

+/* PR tree-optimization/93927 */
+
+__SIZE_TYPE__ strstr (const char *, const char *);
+
+char *
+foo (char *x)
+{
+  return !!strstr (x, "0") ? "0" : "1";
+}

gcc/testsuite/gcc.c-torture/compile/pr93927-2.c

+/* PR tree-optimization/93927 */
+
+__SIZE_TYPE__ strchr (const char *, int);
+
+char *
+foo (char *x)
+{
+  return !!strchr (x, 0) ? "0" : "1";
+}