diff options
Diffstat (limited to 'gcc/tree-ssa-alias.c')
| -rw-r--r-- | gcc/tree-ssa-alias.c | 27 |
1 files changed, 13 insertions, 14 deletions
diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c index eb57010..ecc827a 100644 --- a/gcc/tree-ssa-alias.c +++ b/gcc/tree-ssa-alias.c @@ -2354,7 +2354,6 @@ compute_flow_sensitive_aliasing (struct alias_info *ai) for (i = 0; VEC_iterate (tree, ai->processed_ptrs, i, ptr); i++) { struct ptr_info_def *pi = SSA_NAME_PTR_INFO (ptr); - tree tag = symbol_mem_tag (SSA_NAME_VAR (ptr)); /* Set up aliasing information for PTR's name memory tag (if it has one). Note that only pointers that have been dereferenced will @@ -2362,18 +2361,7 @@ compute_flow_sensitive_aliasing (struct alias_info *ai) if (pi->name_mem_tag && pi->pt_vars) { if (!bitmap_empty_p (pi->pt_vars)) - { - union_alias_set_into (pi->name_mem_tag, pi->pt_vars); - union_alias_set_into (tag, pi->pt_vars); - bitmap_clear_bit (MTAG_ALIASES (tag), DECL_UID (tag)); - - /* It may be the case that this the tag uid was the only - bit we had set in the aliases list, and in this case, - we don't want to keep an empty bitmap, as this - asserts in tree-ssa-operands.c . */ - if (bitmap_empty_p (MTAG_ALIASES (tag))) - BITMAP_FREE (MTAG_ALIASES (tag)); - } + union_alias_set_into (pi->name_mem_tag, pi->pt_vars); } } timevar_pop (TV_FLOW_SENSITIVE); @@ -2860,8 +2848,19 @@ may_alias_p (tree ptr, alias_set_type mem_alias_set, { alias_stats.tbaa_queries++; + /* If the pointed to memory has alias set zero or the pointer + is ref-all, the MEM can alias VAR. */ + if (mem_alias_set == 0 + || PTR_IS_REF_ALL (ptr)) + { + alias_stats.alias_mayalias++; + alias_stats.tbaa_resolved++; + return true; + } + /* If the alias sets don't conflict then MEM cannot alias VAR. */ - if (!alias_sets_conflict_p (mem_alias_set, var_alias_set)) + if (mem_alias_set != var_alias_set + && !alias_set_subset_of (mem_alias_set, var_alias_set)) { alias_stats.alias_noalias++; alias_stats.tbaa_resolved++; |