re PR middle-end/64225 (-funsafe-math-optimizations generates call to pow where…

re PR middle-end/64225 (-funsafe-math-optimizations generates call to pow where multiply instruction would do)

2014-12-09  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>

	PR middle-end/64225
	* tree-ssa-reassoc.c (acceptable_pow_call): Disable transformation
	for BUILT_IN_POW when flag_errno_math is present.

From-SVN: r218546

gcc/ChangeLog

+2014-12-09  Bill Schmidt  <wschmidt@linux.vnet.ibm.com>
+
+	PR middle-end/64225
+	* tree-ssa-reassoc.c (acceptable_pow_call): Disable transformation
+	for BUILT_IN_POW when flag_errno_math is present.
+
 2014-12-09  Ilya Verbin  <ilya.verbin@intel.com>
 
 	* lto-wrapper.c (compile_offload_image): Start processing in_argv

gcc/tree-ssa-reassoc.c

@@ -3988,6 +3988,9 @@ acceptable_pow_call (gimple stmt, tree *base, HOST_WIDE_INT *exponent)
   switch (DECL_FUNCTION_CODE (fndecl))
     {
     CASE_FLT_FN (BUILT_IN_POW):
+      if (flag_errno_math)
+	return false;
+
       *base = gimple_call_arg (stmt, 0);
       arg1 = gimple_call_arg (stmt, 1);