re PR rtl-optimization/62208 (ICE with -fwhole-program on valid code at -O3 on…

re PR rtl-optimization/62208 (ICE with -fwhole-program on valid code at -O3 on x86_64-linux-gnu in trunc_int_for_mode, at explow.c:56)

gcc/
	PR rtl-optimization/62208
	* simplify-rtx.c (simplify_relational_operation_1): Use CONST0_RTX
	rather than const0_rtx in eq/ne-xor simplifications.

gcc/testsuite/
	* gcc.target/i386/pr62208.c: New test.

From-SVN: r215002

gcc/ChangeLog

+2014-09-07  Richard Sandiford  <rdsandiford@googlemail.com>
+
+	PR rtl-optimization/62208
+	* simplify-rtx.c (simplify_relational_operation_1): Use CONST0_RTX
+	rather than const0_rtx in eq/ne-xor simplifications.
+
 2014-09-06  Joern Rennecke  <joern.rennecke@embecosm.com>
 
 	* config/arc/arc.c (arc_print_operand): Fix format for HOST_WIDE_INT.

gcc/simplify-rtx.c

@@ -4480,16 +4480,16 @@ simplify_relational_operation_1 (enum rtx_code code, enum machine_mode mode,
       && op0code == XOR
       && rtx_equal_p (XEXP (op0, 0), op1)
       && !side_effects_p (XEXP (op0, 0)))
-    return simplify_gen_relational (code, mode, cmp_mode,
-				    XEXP (op0, 1), const0_rtx);
+    return simplify_gen_relational (code, mode, cmp_mode, XEXP (op0, 1),
+				    CONST0_RTX (mode));
 
   /* Likewise (eq/ne (xor x y) y) simplifies to (eq/ne x 0).  */
   if ((code == EQ || code == NE)
       && op0code == XOR
       && rtx_equal_p (XEXP (op0, 1), op1)
       && !side_effects_p (XEXP (op0, 1)))
-    return simplify_gen_relational (code, mode, cmp_mode,
-				    XEXP (op0, 0), const0_rtx);
+    return simplify_gen_relational (code, mode, cmp_mode, XEXP (op0, 0),
+				    CONST0_RTX (mode));
 
   /* (eq/ne (xor x C1) C2) simplifies to (eq/ne x (C1^C2)).  */
   if ((code == EQ || code == NE)

gcc/testsuite/ChangeLog

+2014-09-07  Richard Sandiford  <rdsandiford@googlemail.com>
+
+	* gcc.target/i386/pr62208.c: New test.
+
 2014-09-06  John David Anglin  <danglin@gcc.gnu.org>
 
 	PR testsuite/56194

gcc/testsuite/gcc.target/i386/pr62208.c

+/* { dg-options "-O3 -fwhole-program -march=x86-64" } */
+
+int *a;
+unsigned int b;
+
+void fn2 ()
+{
+  int t[9];
+  for (; b; b++)
+    *a ^= (~t[b] != t[b]);
+}
+
+int fn1 ()
+{
+  fn2 (); 
+  return 0; 
+}
+
+int main ()
+{
+  fn1 (); 
+  return 0;
+}