[Bug tree-optimization/42337] New: GCC ICE in compute_antic, at tree-ssa-pre.c:2534

[xinliangli at gmail dot com]

Compiling the attached test case, trunk gcc ICEs (or run out of memory without
the checking). The symptom is similar to the one before PR/41101

The root cause of the problem is the result of an expr's phi_translate depends
on the context it is done -- it may return NULL if it is translated as a
sub-expression due to a bug in the cycle detection.  In this case, after
inlining, there is a loop with swapping code. In computing the ANTIC_IN for the
latch block, the resulting set is ping-ponging -- with two expressions
translated to each other back and forth. The reason that only one of the
expression is in the initial set is due to the translation bug mentioned above.


David


-- 
           Summary: GCC ICE  in compute_antic, at tree-ssa-pre.c:2534
           Product: gcc
           Version: 4.5.0
            Status: UNCONFIRMED
          Severity: major
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: xinliangli at gmail dot com


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42337