[Bug middle-end/67442] [5 Regression] GCC 5.2.0 on x86_64 creates invalid address on specific array index calculation through pointer

["rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67442

--- Comment #15 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Mon Sep 28 10:45:55 2015
New Revision: 228199

URL: https://gcc.gnu.org/viewcvs?rev=228199&root=gcc&view=rev
Log:
2015-09-28  Richard Biener  <rguenther@suse.de>

        Backport from mainline
        2015-08-03  Richard Biener  <rguenther@suse.de>

        PR tree-optimization/66917
        * tree-vectorizer.h (struct dataref_aux): Add base_element_aligned
        field.
        (DR_VECT_AUX): New macro.
        (set_dr_misalignment): Adjust.
        (dr_misalignment): Likewise.
        * tree-vect-data-refs.c (vect_compute_data_ref_alignment):
        Compute whether the base is at least element aligned.
        * tree-vect-stmts.c (ensure_base_align): Adjust.
        (vectorizable_store): If the base is not element aligned
        preserve alignment of the original access if misalignment is unknown.
        (vectorizable_load): Likewise.

        2015-09-16  Richard Biener  <rguenther@suse.de>

        PR middle-end/67442
        * fold-const.c (extract_muldiv_1): Properly extend multiplication
        result before builting a tree via wide_int_to_tree.

        * gcc.dg/torture/pr67442.c: New testcase.

Added:
    branches/gcc-5-branch/gcc/testsuite/gcc.dg/torture/pr67442.c
Modified:
    branches/gcc-5-branch/gcc/ChangeLog
    branches/gcc-5-branch/gcc/fold-const.c
    branches/gcc-5-branch/gcc/testsuite/ChangeLog
    branches/gcc-5-branch/gcc/tree-vect-data-refs.c
    branches/gcc-5-branch/gcc/tree-vect-stmts.c
    branches/gcc-5-branch/gcc/tree-vectorizer.h