[Bug target/88963] gcc generates terrible code for vectors of 64+ length which are not natively supported

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88963

--- Comment #12 from Richard Biener <rguenth at gcc dot gnu.org> ---
Author: rguenth
Date: Fri May  3 10:39:56 2019
New Revision: 270844

URL: https://gcc.gnu.org/viewcvs?rev=270844&root=gcc&view=rev
Log:
2019-05-03  Richard Biener  <rguent...@suse.de>

        PR tree-optimization/88963
        * tree-ssa-forwprop.c (pass_forwprop::execute): Rewrite
        vector loads feeding only BIT_FIELD_REFs to component
        loads.  Rewrite stores fed by CONSTRUCTORs to component
        stores.

        * gcc.dg/tree-ssa/ssa-fre-31.c: Disable forwprop.
        * gcc.target/i386/pr88963-1.c: New testcase.
        * gcc.target/i386/pr88963-2.c: Likewise.

Added:
    trunk/gcc/testsuite/gcc.target/i386/pr88963-1.c
    trunk/gcc/testsuite/gcc.target/i386/pr88963-2.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/tree-ssa/ssa-fre-31.c
    trunk/gcc/tree-ssa-forwprop.c