[Bug tree-optimization/78819] [7 Regression] Wrong code with VRP caused by register assertions along default switch labels

[mpolacek at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78819

--- Comment #4 from Marek Polacek <mpolacek at gcc dot gnu.org> ---
Author: mpolacek
Date: Fri Dec 16 14:19:44 2016
New Revision: 243746

URL: https://gcc.gnu.org/viewcvs?rev=243746&root=gcc&view=rev
Log:
        PR tree-optimization/78819
        * tree-vrp.c (find_switch_asserts): Return if the insertion limit is 0.
        Don't register an assertion if the default case shares a label with
        another case.

        * gcc.dg/tree-ssa/vrp112.c: New test.

Added:
    trunk/gcc/testsuite/gcc.dg/tree-ssa/vrp112.c
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/testsuite/ChangeLog
    trunk/gcc/tree-vrp.c