[Bug rtl-optimization/49847] [4.8 Regression] NULL deref in fold_rtx (prev_insn_cc0 == NULL)

[law at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=49847

--- Comment #40 from Jeffrey A. Law <law at gcc dot gnu.org> ---
Author: law
Date: Fri Dec 18 17:17:14 2015
New Revision: 231821

URL: https://gcc.gnu.org/viewcvs?rev=231821&root=gcc&view=rev
Log:
[PATCH] [PR rtl-optimization/49847] Fix ICE in CSE due to cc0-setter and
cc0-user in different blocks

        PR rtl-optimization/49847
        * cse.c (record_jump_equiv): Handle fold_rtx returning NULL_RTX.

        PR rtl-optimization/49847
        * g++.dg/pr49847-2.C: New test.

Added:
    trunk/gcc/testsuite/g++.dg/pr49847-2.C
Modified:
    trunk/gcc/ChangeLog
    trunk/gcc/cse.c
    trunk/gcc/testsuite/ChangeLog