re PR rtl-optimization/11864 (miscompiles zero extention and test)

	PR 11864
	From Kazumoto Kojima / Dan Kegel:
	* gcc.dg/pr11864-1.c: New test.

From-SVN: r75987

gcc/testsuite/ChangeLog

@@ -5,6 +5,10 @@
 
 2004-01-16  J"orn Rennecke <joern.rennecke@superh.com>
 
+	PR 11864
+	From Kazumoto Kojima / Dan Kegel:
+	* gcc.dg/pr11864-1.c: New test.
+
 	PR 10392
 	From Marcus Comstedt / Dan Kegel:
 	* gcc.dg/pr10392-1.c: New test.

gcc/testsuite/gcc.dg/pr11864-1.c

+/* PR optimization/11864
+ * Reporter: Kazumoto Kojima <kkojima@gcc.gnu.org>
+ * Summary: [3.3/3.4 regression] miscompiles zero extension and test
+ * Description:
+ * gcc-3.3/3.4 -O2 for sh target may miscompile the combination of zero extension
+ * and test if it's zero.
+ *
+ * Testcase tweaked by dank@kegel.com.  Not marked as xfail because it's a regression.
+ */
+/* { dg-do run } */
+/* { dg-options "-O2" } */
+
+extern void abort(void);
+
+int val = 0xff00;
+
+int f(void)
+{
+	return val;
+}
+
+unsigned char a[1];
+
+void foo(void)
+{
+	a[0] = f() & 255;
+
+	if (!a[0])
+		a[0] = f() & 255;
+
+	if (!a[0])
+		a[0] = 1 + (f() & 127);
+}
+
+int main(int argc, char **argv)
+{
+	foo();
+	if (!a[0])
+		abort();
+
+	return 0;
+}