[Bug tree-optimization/44306] New: [4.6 Regression] 464.h264ref fails to build.

[rguenth at gcc dot gnu dot org]

The ifcvt changes cause 464.h264ref to fail to build exhausting virtual memory.
This is appearantly because of shared trees in

#71 0x0000000000a1abe3 in add_to_dst_predicate_list (loop=0x7ffff7edf3f0, 
    e=0x7ffff59a2d40, prev_cond=0x7fffc8c0b0e0, cond=0x7fffc8c0b118)
    at /space/rguenther/src/svn/trunk/gcc/tree-if-conv.c:172
172           new_cond = fold_build2 (TRUTH_AND_EXPR, boolean_type_node,
(gdb) l
167           /* Add the condition COND to the e->aux field.  In case the edge
168              destination is a PHI node, this condition will be added to
169              the block predicate to construct a complete condition.  */
170           e->aux = cond;
171
172           new_cond = fold_build2 (TRUTH_AND_EXPR, boolean_type_node,
173                                   unshare_expr (prev_cond), cond);

so unsharing never finishes (well, or maybe we just endlessly add
conds here - which is equally bad).


-- 
           Summary: [4.6 Regression] 464.h264ref fails to build.
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned at gcc dot gnu dot org
        ReportedBy: rguenth at gcc dot gnu dot org


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44306