Backport PRs 70022, 70484, 70931, 71452

Backport PRs 70022, 70484, 70931, 71452

2016-07-07  Richard Biener  <rguenther@suse.de>

	Backport from mainline
	2016-04-04  Richard Biener  <rguenther@suse.de>

	PR rtl-optimization/70484
	* rtl.h (canon_output_dependence): Declare.
	* alias.c (canon_output_dependence): New function.
	* dse.c (record_store): Use canon_output_dependence rather
	than canon_true_dependence.

	* gcc.dg/torture/pr70484.c: New testcase.

	2016-06-08  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/71452
	* tree-ssa.c (non_rewritable_lvalue_p): Make sure that the
	type used for the SSA rewrite has enough precision to cover
	the dynamic type of the location.

	* gcc.dg/torture/pr71452.c: New testcase.

	2016-05-06  Richard Biener  <rguenther@suse.de>

	PR middle-end/70931
	* dwarf2out.c (native_encode_initializer): Skip zero-sized fields.

	* gfortran.dg/pr70931.f90: New testcase.

	2016-03-01  Richard Biener  <rguenther@suse.de>

	PR middle-end/70022
	* fold-const.c (fold_indirect_ref_1): Fix range checking for
	vector BIT_FIELD_REF extract.

	* gcc.dg/pr70022.c: New testcase.

From-SVN: r238087