------- Comment #7 from steven at gcc dot gnu dot org 2006-04-20 20:53 ------- I have tested this test case again with lcm.c patched with the patch below to check for insertions on edges where an expression is already available. The abort does not trigger.
The version of GCC that I patched and tested was extracted from SVN with the following commands: svn co -r {"2004-08-10 15:10"} (etc.) Index: lcm.c =================================================================== --- lcm.c (revision 85749) +++ lcm.c (working copy) @@ -426,10 +426,6 @@ pre_edge_lcm (FILE *file ATTRIBUTE_UNUSE dump_sbitmap_vector (file, "earliest", "", earliest, num_edges); #endif - sbitmap_vector_free (antout); - sbitmap_vector_free (antin); - sbitmap_vector_free (avout); - later = sbitmap_vector_alloc (num_edges, n_exprs); /* Allocate an extra element for the exit block in the laterin vector. */ @@ -462,6 +458,32 @@ pre_edge_lcm (FILE *file ATTRIBUTE_UNUSE } #endif +#if 1 + { + sbitmap *avout_check; + sbitmap *insert_ = *insert; + int x; + + avout_check = sbitmap_vector_alloc (num_edges, n_exprs); + sbitmap_vector_zero (avout_check, num_edges); + + for (x = 0; x < num_edges; x++) + { + basic_block bb = INDEX_EDGE_PRED_BB (edge_list, x); + if (bb->index < 0) + continue; + sbitmap_copy (avout_check[x], avout[bb->index]); + sbitmap_a_and_b (avout_check[x], avout_check[x], insert_[x]); + if (sbitmap_first_set_bit (avout_check[x]) >= 0) + abort (); + } + } +#endif + + sbitmap_vector_free (antout); + sbitmap_vector_free (antin); + sbitmap_vector_free (avout); + return edge_list; } -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=16967