[Bug tree-optimization/85720] bad codegen for looped assignment of primitives at -O2

[amker at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85720

--- Comment #7 from bin cheng <amker at gcc dot gnu.org> ---
Author: amker
Date: Fri May 25 11:09:42 2018
New Revision: 260753

URL: https://gcc.gnu.org/viewcvs?rev=260753&root=gcc&view=rev
Log:
        PR tree-optimization/85720

        * tree-loop-distribution.c (break_alias_scc_partitions): Don't merge
        SCC if all partitions are builtins.
        (version_loop_by_alias_check): New parameter.  Generate cancelable
        runtime alias check if all partitions are builtins.
        (distribute_loop): Update call to above function.

        gcc/testsuite
        * gcc.dg/tree-ssa/pr85720.c: New test.
        * gcc.target/i386/avx256-unaligned-store-2.c: Disable loop pattern
        distribution.

Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr85720.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.target/i386/avx256-unaligned-store-2.c
    trunk/gcc/tree-loop-distribution.c