[Bug tree-optimization/51238] New: ICE: SIGSEGV in find_uses_to_rename_use (tree-ssa-loop-manip.c:1267) with -Os -ftree-loop-distribution

["zsojka at seznam dot cz" <gcc-bugzilla at gcc dot gnu dot org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=51238

             Bug #: 51238
           Summary: ICE: SIGSEGV in find_uses_to_rename_use
                    (tree-ssa-loop-manip.c:1267) with -Os
                    -ftree-loop-distribution
    Classification: Unclassified
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: tree-optimization
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: zsojka@seznam.cz
              Host: x86_64-pc-linux-gnu
            Target: x86_64-pc-linux-gnu


Created attachment 25867
  --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25867
reduced testcase

Compiler output:
$ gcc -Os -ftree-loop-distribution testcase.c
==22140== Invalid read of size 8
==22140==    at 0xACBDBC: find_uses_to_rename_use(basic_block_def*, tree_node*,
bitmap_head_def**, bitmap_head_def*) (tree-ssa-loop-manip.c:1267)
==22140==    by 0xACBFFB: find_uses_to_rename_bb(basic_block_def*,
bitmap_head_def**, bitmap_head_def*) (tree-ssa-loop-manip.c:302)
==22140==    by 0xACC7D5: rewrite_into_loop_closed_ssa(bitmap_head_def*,
unsigned int) (tree-ssa-loop-manip.c:331)
==22140==    by 0xA320E1: distribute_loop(loop*, VEC_gimple_heap*)
(tree-loop-distribution.c:1142)
==22140==    by 0xA32E33: tree_loop_distribution()
(tree-loop-distribution.c:1280)
==22140==    by 0x8DF634: execute_one_pass(opt_pass*) (passes.c:2074)
==22140==    by 0x8DF9D4: execute_pass_list(opt_pass*) (passes.c:2129)
==22140==    by 0x8DF9E6: execute_pass_list(opt_pass*) (passes.c:2130)
==22140==    by 0x8DF9E6: execute_pass_list(opt_pass*) (passes.c:2130)
==22140==    by 0xA4156D: tree_rest_of_compilation(tree_node*)
(tree-optimize.c:420)
==22140==    by 0x6948A9: cgraph_expand_function(cgraph_node*)
(cgraphunit.c:1819)
==22140==    by 0x69664B: cgraph_optimize() (cgraphunit.c:1886)
==22140==    by 0x696DB9: cgraph_finalize_compilation_unit()
(cgraphunit.c:1327)
==22140==    by 0x574F6F: c_write_global_declarations() (c-decl.c:10023)
==22140==    by 0x9D48D3: toplev_main(int, char**) (toplev.c:581)
==22140==    by 0x674ED2C: (below main) (in /lib64/libc-2.12.2.so)
==22140==  Address 0x10 is not stack'd, malloc'd or (recently) free'd
==22140== 
testcase.c: In function 'foo':
testcase.c:6:1: internal compiler error: Segmentation fault
Please submit a full bug report,
with preprocessed source if appropriate.
See <http://gcc.gnu.org/bugs.html> for instructions.

Tested revisions:
r181508 - crash
4.6 r180325 - crash
4.5 r180325 - crash
4.4 r180325 - ICE: in update_alias_info_1, at tree-ssa-alias.c:2551