[PATCH] Fix PR64295

[Richard Biener]

Bootstrapped and tested on x86_64-unknown-linux-gnu, applied.

Richard.

2014-12-15  Richard Biener  <rguent...@suse.de>

        PR middle-end/64295
        * match.pd (X / CST -> X * (1 / CST): Use const_binop instead of
        fold_binary to compute the constant to multiply with.

        * gcc.dg/pr64295.c: New testcase.

Index: gcc/match.pd
===================================================================
--- gcc/match.pd        (revision 218668)
+++ gcc/match.pd        (working copy)
@@ -186,7 +186,7 @@ (define_operator_list inverted_tcc_compa
    (if (flag_reciprocal_math
        && !real_zerop (@1))
     (with
-     { tree tem = fold_binary (RDIV_EXPR, type, build_one_cst (type), @1); }
+     { tree tem = const_binop (RDIV_EXPR, type, build_one_cst (type), @1); }
      (if (tem)
       (mult @0 { tem; } ))))
    (if (cst != COMPLEX_CST)
Index: gcc/testsuite/gcc.dg/pr64295.c
===================================================================
--- gcc/testsuite/gcc.dg/pr64295.c      (revision 0)
+++ gcc/testsuite/gcc.dg/pr64295.c      (working copy)
@@ -0,0 +1,8 @@
+/* { dg-do compile } */
+/* { dg-options "-O -frounding-math -funsafe-math-optimizations" } */
+
+double
+f (double g)
+{
+  return g / 3;
+}