diff options
Diffstat (limited to 'gcc/tree-ssa-alias.c')
| -rw-r--r-- | gcc/tree-ssa-alias.c | 50 |
1 files changed, 36 insertions, 14 deletions
diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c index 52ca86b48df..1ff3821ed5a 100644 --- a/gcc/tree-ssa-alias.c +++ b/gcc/tree-ssa-alias.c @@ -364,7 +364,7 @@ add_to_worklist (tree alias, VEC (tree, heap) **worklist, static void mark_aliases_call_clobbered (tree tag, VEC (tree, heap) **worklist, VEC (int, heap) **worklist2, - bitmap on_worklist) + bitmap on_worklist, bitmap queued) { bitmap aliases; bitmap_iterator bi; @@ -387,13 +387,7 @@ mark_aliases_call_clobbered (tree tag, VEC (tree, heap) **worklist, in order to allow C/C++ tricks that involve pointer arithmetic to work. */ if (TREE_CODE (entry) == STRUCT_FIELD_TAG) - { - subvar_t svars; - svars = get_subvars_for_var (SFT_PARENT_VAR (entry)); - for (; svars; svars = svars->next) - if (!unmodifiable_var_p (entry)) - mark_call_clobbered (svars->var, ta->escape_mask); - } + bitmap_set_bit (queued, DECL_UID (SFT_PARENT_VAR (entry))); else if (!unmodifiable_var_p (entry)) { add_to_worklist (entry, worklist, worklist2, ta->escape_mask, @@ -401,6 +395,18 @@ mark_aliases_call_clobbered (tree tag, VEC (tree, heap) **worklist, mark_call_clobbered (entry, ta->escape_mask); } } + if (!bitmap_empty_p (queued)) + { + EXECUTE_IF_SET_IN_BITMAP (queued, 0, i, bi) + { + subvar_t svars; + svars = get_subvars_for_var (referenced_var (i)); + for (; svars; svars = svars->next) + if (!unmodifiable_var_p (svars->var)) + mark_call_clobbered (svars->var, ta->escape_mask); + } + bitmap_clear (queued); + } } /* Tags containing global vars need to be marked as global. @@ -508,6 +514,11 @@ set_initial_properties (struct alias_info *ai) referenced_var_iterator rvi; tree var; tree ptr; + bitmap queued; + + /* Temporary bitmap to avoid quadratic behavior in marking + call clobbers. */ + queued = BITMAP_ALLOC (&alias_bitmap_obstack); FOR_EACH_REFERENCED_VAR (var, rvi) { @@ -557,15 +568,22 @@ set_initial_properties (struct alias_info *ai) in order to allow C/C++ tricks that involve pointer arithmetic to work. */ if (TREE_CODE (alias) == STRUCT_FIELD_TAG) + bitmap_set_bit (queued, DECL_UID (SFT_PARENT_VAR (alias))); + else if (!unmodifiable_var_p (alias)) + mark_call_clobbered (alias, pi->escape_mask); + } + /* Process variables we need to clobber all parts of. */ + if (!bitmap_empty_p (queued)) + { + EXECUTE_IF_SET_IN_BITMAP (queued, 0, j, bi) { subvar_t svars; - svars = get_subvars_for_var (SFT_PARENT_VAR (alias)); + svars = get_subvars_for_var (referenced_var (j)); for (; svars; svars = svars->next) - if (!unmodifiable_var_p (alias)) + if (!unmodifiable_var_p (svars->var)) mark_call_clobbered (svars->var, pi->escape_mask); } - else if (!unmodifiable_var_p (alias)) - mark_call_clobbered (alias, pi->escape_mask); + bitmap_clear (queued); } } } @@ -600,6 +618,8 @@ set_initial_properties (struct alias_info *ai) MTAG_GLOBAL (tag) = true; } } + + BITMAP_FREE (queued); } /* Compute which variables need to be marked call clobbered because @@ -611,10 +631,11 @@ compute_call_clobbered (struct alias_info *ai) { VEC (tree, heap) *worklist = NULL; VEC (int,heap) *worklist2 = NULL; - bitmap on_worklist; + bitmap on_worklist, queued; timevar_push (TV_CALL_CLOBBER); on_worklist = BITMAP_ALLOC (NULL); + queued = BITMAP_ALLOC (NULL); set_initial_properties (ai); init_transitive_clobber_worklist (&worklist, &worklist2, on_worklist); @@ -626,11 +647,12 @@ compute_call_clobbered (struct alias_info *ai) bitmap_clear_bit (on_worklist, DECL_UID (curr)); mark_call_clobbered (curr, reason); mark_aliases_call_clobbered (curr, &worklist, &worklist2, - on_worklist); + on_worklist, queued); } VEC_free (tree, heap, worklist); VEC_free (int, heap, worklist2); BITMAP_FREE (on_worklist); + BITMAP_FREE (queued); compute_tag_properties (); timevar_pop (TV_CALL_CLOBBER); } |