r195664 - in /branches/gcc-4_7-branch/gcc: Chan...

[jakub@gcc.gnu.org]

Author: jakub
Date: Fri Feb  1 14:17:50 2013
New Revision: 195664

URL: http://gcc.gnu.org/viewcvs?root=gcc&view=rev&rev=195664
Log:
	Backported from mainline
	2013-01-28  Jakub Jelinek  <jakub@redhat.com>

	PR tree-optimization/56125
	* tree-ssa-math-opts.c (gimple_expand_builtin_pow): Don't optimize
	pow(x,c) into sqrt(x) * powi(x, n/2) or
	1.0 / (sqrt(x) * powi(x, abs(n/2))) if c is an integer or when
	optimizing for size.
	Don't optimize pow(x,c) into powi(x, n/3) * powi(cbrt(x), n%3) or
	1.0 / (powi(x, abs(n)/3) * powi(cbrt(x), abs(n)%3)) if 2c is an
	integer.

	* gcc.dg/pr56125.c: New test.

Added:
    branches/gcc-4_7-branch/gcc/testsuite/gcc.dg/pr56125.c
Modified:
    branches/gcc-4_7-branch/gcc/ChangeLog
    branches/gcc-4_7-branch/gcc/testsuite/ChangeLog
    branches/gcc-4_7-branch/gcc/tree-ssa-math-opts.c