[PATCH][PR tree-optimization/68198] Avoid CFG explosion due to threading
authorJeff Law <law@redhat.com>
Thu, 19 Nov 2015 00:33:27 +0000 (17:33 -0700)
committerJeff Law <law@gcc.gnu.org>
Thu, 19 Nov 2015 00:33:27 +0000 (17:33 -0700)
commit7d7e7aca3bcded9bccc3ebb4c020287ff21ef102
treecdce52b09099f2ec47842495fd8697f9d46bc078
parent3ebf5a30cf7ef66b150a6a217636744329fcfe2b
[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.

From-SVN: r230586
gcc/ChangeLog
gcc/testsuite/ChangeLog
gcc/testsuite/gcc.dg/tree-ssa/pr66752-3.c
gcc/testsuite/gcc.dg/tree-ssa/pr68198.c [new file with mode: 0644]
gcc/tree-ssa-threadupdate.c