[Bug tree-optimization/68198] [6 Regression]Excessive code size, compile time and memory usage bloat due to FSM threading in 453.povray

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

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68198

--- Comment #9 from Jeffrey A. Law <law at gcc dot gnu.org> ---
Author: law
Date: Thu Nov 19 00:33:27 2015
New Revision: 230586

URL: https://gcc.gnu.org/viewcvs?rev=230586&root=gcc&view=rev
Log:
[PATCH][PR tree-optimization/68198] Avoid CFG explosion due to threading

        PR tree-optimization/68198
        * tree-ssa-threadupdate.c (valid_jump_thread_path): Distinguish
        between threading a multi-way branch and a thread path that contains
        a multi-way branch.  Disallow the case where a path contains a
        multi-way branch and does not thread a multi-way branch.
        (thread_through_all_blocks): Update comment.

        PR tree-optimization/68198
        * gcc.dg/tree-ssa/pr66752-3.c: Update expected output for VRP1.
        * gcc.dg/tree-ssa/pr68198.c: New test.

Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr68198.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/testsuite/gcc.dg/tree-ssa/pr66752-3.c
    trunk/gcc/tree-ssa-threadupdate.c