r244918 - in /branches/gcc-5-branch/gcc: Change...

[rguenth@gcc.gnu.org]

Author: rguenth
Date: Thu Jan 26 08:16:37 2017
New Revision: 244918

URL: https://gcc.gnu.org/viewcvs?rev=244918&root=gcc&view=rev
Log:
2017-01-26  Richard Biener  <rguenther@suse.de>

	Backport from mainline
	2016-09-27  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/77745
	* tree-ssa-pre.c (eliminate_dom_walker::before_dom_children):
	When removing redundant stores make sure to check compatibility
	of the TBAA state for downstream accesses.
	* tree-ssa-sccvn.c (visit_reference_op_store): Likewise for when
	value-numbering virtual operands for store matches.

	* g++.dg/torture/pr77745.C: New testcase.

	2016-09-29  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/77768
	* tree-ssa-sccvn.c (visit_reference_op_store): Properly deal
	with stores to a place we know has a constant value.
	* tree-vrp.c (set_defs_to_varying): New helper avoiding
	writing to vr_const_varying.
	(vrp_initialize): Call it.
	(vrp_visit_stmt): Likewise.
	(evrp_dom_walker::before_dom_children): Likewise.
	* tree-ssa-pre.c (eliminate_dom_walker::before_dom_children):
	Handle stores to readonly memory when removing redundant stores.

	* gcc.dg/torture/pr77768.c: New testcase.

Added:
    branches/gcc-5-branch/gcc/testsuite/g++.dg/torture/pr77745.C
    branches/gcc-5-branch/gcc/testsuite/gcc.dg/torture/pr77768.c
Modified:
    branches/gcc-5-branch/gcc/ChangeLog
    branches/gcc-5-branch/gcc/testsuite/ChangeLog
    branches/gcc-5-branch/gcc/tree-ssa-pre.c
    branches/gcc-5-branch/gcc/tree-ssa-sccvn.c
    branches/gcc-5-branch/gcc/tree-vrp.c