re PR tree-optimization/66759 (ICE in generic-match.c on 456.hmmer)

2015-07-06  Richard Biener  <rguenther@suse.de>

	PR middle-end/66759
	* match.pd: Add missing constraint of y to REAL_CST in
	REAL_CST - x CMP y to y - CST CMP x simplification.

	* gcc.dg/torture/pr66759.c: New testcase.

From-SVN: r225449

gcc/ChangeLog

+2015-07-06  Richard Biener  <rguenther@suse.de>
+
+	PR middle-end/66759
+	* match.pd: Add missing constraint of y to REAL_CST in
+	REAL_CST - x CMP y to y - CST CMP x simplification.
+
 2015-07-06  Eric Botcazou  <ebotcazou@adacore.com>
 
 	PR tree-optimization/66757

gcc/match.pd

@@ -1497,7 +1497,7 @@ along with GCC; see the file COPYING3.  If not see
     floating-point types only if -fassociative-math is set.  */
  (if (flag_associative_math)
   (simplify
-   (cmp (minus REAL_CST@0 @1) @2)
+   (cmp (minus REAL_CST@0 @1) REAL_CST@2)
    (with { tree tem = const_binop (MINUS_EXPR, TREE_TYPE (@1), @0, @2); }
     (if (!TREE_OVERFLOW (tem))
      (cmp { tem; } @1)))))

gcc/testsuite/ChangeLog

+2015-07-06  Richard Biener  <rguenther@suse.de>
+
+	PR middle-end/66759
+	* gcc.dg/torture/pr66759.c: New testcase.
+
 2015-07-06  Andre Vehreschild  <vehre@gmx.de>
 
 	PR fortran/58586

gcc/testsuite/gcc.dg/torture/pr66759.c

+/* { dg-do compile } */
+/* { dg-additional-options "-ffast-math" } */
+
+int a, b;
+float c;
+int fn2();
+void fn1()
+{
+  if (fn2() <= 1. - c)
+    b = a;
+}