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| author | Richard Guenther <rguenther@suse.de> | 2008-04-23 14:06:02 +0000 |
|---|---|---|
| committer | Richard Biener <rguenth@gcc.gnu.org> | 2008-04-23 14:06:02 +0000 |
| commit | a7a512beff448f28fc2f9f192e19e30cbf971eba (patch) | |
| tree | 92b446ae6c5a7e1732e139eb7761d3c20bb21399 | |
| parent | f3f75f693d12f58acbb37d393280081621eb3f58 (diff) | |
| download | gcc-a7a512beff448f28fc2f9f192e19e30cbf971eba.zip gcc-a7a512beff448f28fc2f9f192e19e30cbf971eba.tar.gz gcc-a7a512beff448f28fc2f9f192e19e30cbf971eba.tar.bz2 | |
alias.c (alias_set_subset_of): Correctly handle asking if zero is a subset of an alias set with zero child.
2008-04-23 Richard Guenther <rguenther@suse.de>
* alias.c (alias_set_subset_of): Correctly handle asking
if zero is a subset of an alias set with zero child.
* tree-ssa-alias.c (have_common_aliases_p): Simplify logic.
(compute_flow_insensitive_aliasing): Correctly walk all
pointers. Do not unnecessarily union sets.
From-SVN: r134597
| -rw-r--r-- | gcc/ChangeLog | 8 | ||||
| -rw-r--r-- | gcc/alias.c | 5 | ||||
| -rw-r--r-- | gcc/tree-ssa-alias.c | 22 |
3 files changed, 18 insertions, 17 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index f0fb840..a774a43 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,13 @@ 2008-04-23 Richard Guenther <rguenther@suse.de> + * alias.c (alias_set_subset_of): Correctly handle asking + if zero is a subset of an alias set with zero child. + * tree-ssa-alias.c (have_common_aliases_p): Simplify logic. + (compute_flow_insensitive_aliasing): Correctly walk all + pointers. Do not unnecessarily union sets. + +2008-04-23 Richard Guenther <rguenther@suse.de> + PR middle-end/36021 * c-common.c (handle_alloc_size_attribute): Use type_num_arguments. diff --git a/gcc/alias.c b/gcc/alias.c index 2e4f5ae..7b14f26 100644 --- a/gcc/alias.c +++ b/gcc/alias.c @@ -305,8 +305,9 @@ alias_set_subset_of (alias_set_type set1, alias_set_type set2) /* Otherwise, check if set1 is a subset of set2. */ ase = get_alias_set_entry (set2); if (ase != 0 - && (splay_tree_lookup (ase->children, - (splay_tree_key) set1))) + && ((ase->has_zero_child && set1 == 0) + || splay_tree_lookup (ase->children, + (splay_tree_key) set1))) return true; return false; } diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c index a9ae29f..eb57010 100644 --- a/gcc/tree-ssa-alias.c +++ b/gcc/tree-ssa-alias.c @@ -2390,9 +2390,7 @@ have_common_aliases_p (bitmap tag1aliases, bitmap tag2aliases) /* This is the old behavior of have_common_aliases_p, which is to return false if both sets are empty, or one set is and the other isn't. */ - if ((tag1aliases == NULL && tag2aliases != NULL) - || (tag2aliases == NULL && tag1aliases != NULL) - || (tag1aliases == NULL && tag2aliases == NULL)) + if (tag1aliases == NULL || tag2aliases == NULL) return false; return bitmap_intersect_p (tag1aliases, tag2aliases); @@ -2490,12 +2488,16 @@ compute_flow_insensitive_aliasing (struct alias_info *ai) if (PTR_IS_REF_ALL (p_map1->var)) continue; - for (j = i + 1; j < ai->num_pointers; j++) + for (j = 0; j < ai->num_pointers; j++) { struct alias_map_d *p_map2 = ai->pointers[j]; tree tag2 = symbol_mem_tag (p_map2->var); bitmap may_aliases2 = may_aliases (tag2); + /* By convention tags don't alias themselves. */ + if (tag1 == tag2) + continue; + if (PTR_IS_REF_ALL (p_map2->var)) continue; @@ -2508,18 +2510,8 @@ compute_flow_insensitive_aliasing (struct alias_info *ai) if (have_common_aliases_p (may_aliases1, may_aliases2)) continue; - if (may_aliases2 && !bitmap_empty_p (may_aliases2)) - { - union_alias_set_into (tag1, may_aliases2); - } - else - { - /* Since TAG2 does not have any aliases of its own, add - TAG2 itself to the alias set of TAG1. */ - add_may_alias (tag1, tag2); - } + add_may_alias (tag1, tag2); } - } timevar_pop (TV_FLOW_INSENSITIVE); } |