Fix if-conversion pass for dead type-unsafe code

Fix if-conversion pass for dead type-unsafe code

2014-08-15  Tom de Vries  <tom@codesourcery.com>

	Backport from mainline:
	2014-08-14  Tom de Vries  <tom@codesourcery.com>

	PR rtl-optimization/62004
	PR rtl-optimization/62030
	* ifcvt.c (rtx_interchangeable_p): New function.
	(noce_try_move, noce_process_if_block): Use rtx_interchangeable_p.

	* gcc.dg/pr62004.c: New test.
	* gcc.dg/pr62030.c: Same.
	* gcc.target/mips/pr62030-octeon.c: Same.

	2014-08-05  Richard Biener  <rguenther@suse.de>

	* emit-rtl.h (mem_attrs_eq_p): Declare.
	* emit-rtl.c (mem_attrs_eq_p): Export.

From-SVN: r214067