diff options
| -rw-r--r-- | gcc/ChangeLog | 6 | ||||
| -rw-r--r-- | gcc/tree-switch-conversion.c | 35 |
2 files changed, 37 insertions, 4 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 788574b5290..60ffb7d9cf4 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,9 @@ +2012-05-03 Steven Bosscher <steven@gcc.gnu.org> + + * tree-switch-conversion.c (gen_inbound_check): Free post-dominance + information as early as possible. Update dominance info instead of + discarding it. + 2012-05-03 Richard Guenther <rguenther@suse.de> * tree-ssa-pre.c (debug_bitmap_sets_for): New function. diff --git a/gcc/tree-switch-conversion.c b/gcc/tree-switch-conversion.c index 3d10750e4dc..4f3d1d30f20 100644 --- a/gcc/tree-switch-conversion.c +++ b/gcc/tree-switch-conversion.c @@ -800,6 +800,14 @@ gen_inbound_check (gimple swtch, struct switch_conv_info *info) location_t loc = gimple_location (swtch); gcc_assert (info->default_values); + + /* Make no effort to update the post-dominator tree. It is actually not + that hard for the transformations we have performed, but it is not + supported by iterate_fix_dominators. + Freeing post-dominance info is dome early to avoid pointless work in + create_basic_block, which is called when we split SWITCH_BB. */ + free_dominance_info (CDI_POST_DOMINATORS); + bb0 = gimple_bb (swtch); tidx = gimple_assign_lhs (info->arr_ref_first); @@ -866,13 +874,32 @@ gen_inbound_check (gimple swtch, struct switch_conv_info *info) bb2->frequency = EDGE_FREQUENCY (e02); bbf->frequency = EDGE_FREQUENCY (e1f) + EDGE_FREQUENCY (e2f); - prune_bbs (bbd, info->final_bb); /* To keep calc_dfs_tree() in dominance.c - happy. */ + /* Tidy blocks that have become unreachable. */ + prune_bbs (bbd, info->final_bb); + /* Fixup the PHI nodes in bbF. */ fix_phi_nodes (e1f, e2f, bbf, info); - free_dominance_info (CDI_DOMINATORS); - free_dominance_info (CDI_POST_DOMINATORS); + /* Fix the dominator tree, if it is available. */ + if (dom_info_available_p (CDI_DOMINATORS)) + { + VEC (basic_block, heap) *bbs_to_fix_dom; + + set_immediate_dominator (CDI_DOMINATORS, bb1, bb0); + set_immediate_dominator (CDI_DOMINATORS, bb2, bb0); + if (! get_immediate_dominator(CDI_DOMINATORS, bbf)) + /* If bbD was the immediate dominator ... */ + set_immediate_dominator (CDI_DOMINATORS, bbf, bb0); + + bbs_to_fix_dom = VEC_alloc (basic_block, heap, 4); + VEC_quick_push (basic_block, bbs_to_fix_dom, bb0); + VEC_quick_push (basic_block, bbs_to_fix_dom, bb1); + VEC_quick_push (basic_block, bbs_to_fix_dom, bb2); + VEC_quick_push (basic_block, bbs_to_fix_dom, bbf); + + iterate_fix_dominators (CDI_DOMINATORS, bbs_to_fix_dom, true); + VEC_free (basic_block, heap, bbs_to_fix_dom); + } } /* The following function is invoked on every switch statement (the current one |