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-rw-r--r--gcc/tree-ssa-alias.c121
1 files changed, 104 insertions, 17 deletions
diff --git a/gcc/tree-ssa-alias.c b/gcc/tree-ssa-alias.c
index 17bf8c5cb76..de39ed128f4 100644
--- a/gcc/tree-ssa-alias.c
+++ b/gcc/tree-ssa-alias.c
@@ -371,7 +371,7 @@ struct tree_opt_pass pass_may_alias =
PROP_alias, /* properties_provided */
0, /* properties_destroyed */
0, /* todo_flags_start */
- TODO_dump_func | TODO_rename_vars
+ TODO_dump_func | TODO_update_ssa
| TODO_ggc_collect | TODO_verify_ssa
| TODO_verify_stmts, /* todo_flags_finish */
0 /* letter */
@@ -407,7 +407,7 @@ count_ptr_derefs (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED, void *data)
*NUM_DEREFS_P respectively. *IS_STORE_P is set to 'true' if at
least one of those dereferences is a store operation. */
-static void
+void
count_uses_and_derefs (tree ptr, tree stmt, unsigned *num_uses_p,
unsigned *num_derefs_p, bool *is_store)
{
@@ -770,7 +770,7 @@ compute_points_to_and_addr_escape (struct alias_info *ai)
/* Mark variables in V_MAY_DEF operands as being written to. */
FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_VIRTUAL_DEFS)
{
- tree var = SSA_NAME_VAR (op);
+ tree var = DECL_P (op) ? op : SSA_NAME_VAR (op);
var_ann_t ann = var_ann (var);
bitmap_set_bit (ai->written_vars, ann->uid);
}
@@ -855,7 +855,7 @@ create_name_tags (struct alias_info *ai)
needs to be removed from the IL, so we mark it for
renaming. */
if (old_name_tag && old_name_tag != pi->name_mem_tag)
- bitmap_set_bit (vars_to_rename, var_ann (old_name_tag)->uid);
+ mark_sym_for_renaming (old_name_tag);
}
else if (pi->pt_malloc)
{
@@ -875,7 +875,7 @@ create_name_tags (struct alias_info *ai)
|= TREE_THIS_VOLATILE (TREE_TYPE (TREE_TYPE (ptr)));
/* Mark the new name tag for renaming. */
- bitmap_set_bit (vars_to_rename, var_ann (pi->name_mem_tag)->uid);
+ mark_sym_for_renaming (pi->name_mem_tag);
}
}
@@ -1000,7 +1000,11 @@ compute_flow_insensitive_aliasing (struct alias_info *ai)
|| bitmap_bit_p (ai->written_vars, v_ann->uid);
if (!tag_stored_p && !var_stored_p)
continue;
-
+
+ if ((unmodifiable_var_p (tag) && !unmodifiable_var_p (var))
+ || (unmodifiable_var_p (var) && !unmodifiable_var_p (tag)))
+ continue;
+
if (may_alias_p (p_map->var, p_map->set, var, v_map->set))
{
subvar_t svars;
@@ -1449,9 +1453,10 @@ setup_pointers_and_addressables (struct alias_info *ai)
&& !is_global_var (var))
{
bool okay_to_mark = true;
+
/* Since VAR is now a regular GIMPLE register, we will need
to rename VAR into SSA afterwards. */
- bitmap_set_bit (vars_to_rename, v_ann->uid);
+ mark_sym_for_renaming (var);
if (var_can_have_subvars (var)
&& (svars = get_subvars_for_var (var)))
@@ -1463,15 +1468,15 @@ setup_pointers_and_addressables (struct alias_info *ai)
var_ann_t svann = var_ann (sv->var);
if (bitmap_bit_p (ai->addresses_needed, svann->uid))
okay_to_mark = false;
- bitmap_set_bit (vars_to_rename, svann->uid);
+ mark_sym_for_renaming (sv->var);
}
}
+
/* The address of VAR is not needed, remove the
addressable bit, so that it can be optimized as a
regular variable. */
if (okay_to_mark)
mark_non_addressable (var);
-
}
else
{
@@ -1496,7 +1501,7 @@ setup_pointers_and_addressables (struct alias_info *ai)
if (may_be_aliased (var))
{
create_alias_map_for (var, ai);
- bitmap_set_bit (vars_to_rename, var_ann (var)->uid);
+ mark_sym_for_renaming (var);
}
/* Add pointer variables that have been dereferenced to the POINTERS
@@ -1519,7 +1524,13 @@ setup_pointers_and_addressables (struct alias_info *ai)
afterwards. Note that we cannot do this inside
get_tmt_for because aliasing may run multiple times
and we only create type tags the first time. */
- bitmap_set_bit (vars_to_rename, t_ann->uid);
+ mark_sym_for_renaming (tag);
+
+ /* Similarly, if pointer VAR used to have another type
+ tag, we will need to process it in the renamer to
+ remove the stale virtual operands. */
+ if (v_ann->type_mem_tag)
+ mark_sym_for_renaming (v_ann->type_mem_tag);
/* Associate the tag with pointer VAR. */
v_ann->type_mem_tag = tag;
@@ -1555,7 +1566,7 @@ setup_pointers_and_addressables (struct alias_info *ai)
tree tag = ann->type_mem_tag;
if (tag)
{
- bitmap_set_bit (vars_to_rename, var_ann (tag)->uid);
+ mark_sym_for_renaming (tag);
ann->type_mem_tag = NULL_TREE;
}
}
@@ -1661,11 +1672,11 @@ maybe_create_global_var (struct alias_info *ai)
{
subvar_t sv;
for (sv = svars; sv; sv = sv->next)
- bitmap_set_bit (vars_to_rename, var_ann (sv->var)->uid);
+ mark_sym_for_renaming (sv->var);
}
}
- bitmap_set_bit (vars_to_rename, var_ann (var)->uid);
+ mark_sym_for_renaming (var);
}
}
@@ -1802,7 +1813,7 @@ set_pt_anything (tree ptr)
disassociated from PTR. */
if (pi->name_mem_tag)
{
- bitmap_set_bit (vars_to_rename, var_ann (pi->name_mem_tag)->uid);
+ mark_sym_for_renaming (pi->name_mem_tag);
pi->name_mem_tag = NULL_TREE;
}
}
@@ -2358,7 +2369,7 @@ create_global_var (void)
TREE_ADDRESSABLE (global_var) = 0;
add_referenced_tmp_var (global_var);
- bitmap_set_bit (vars_to_rename, var_ann (global_var)->uid);
+ mark_sym_for_renaming (global_var);
}
@@ -2673,6 +2684,83 @@ may_be_aliased (tree var)
return true;
}
+
+/* Add VAR to the list of may-aliases of PTR's type tag. If PTR
+ doesn't already have a type tag, create one. */
+
+void
+add_type_alias (tree ptr, tree var)
+{
+ varray_type aliases;
+ tree tag;
+ var_ann_t ann = var_ann (ptr);
+
+ if (ann->type_mem_tag == NULL_TREE)
+ {
+ size_t i;
+ tree q = NULL_TREE;
+ tree tag_type = TREE_TYPE (TREE_TYPE (ptr));
+ HOST_WIDE_INT tag_set = get_alias_set (tag_type);
+
+ /* PTR doesn't have a type tag, create a new one and add VAR to
+ the new tag's alias set.
+
+ FIXME, This is slower than necessary. We need to determine
+ whether there is another pointer Q with the same alias set as
+ PTR. This could be sped up by having type tags associated
+ with types. */
+ for (i = 0; i < num_referenced_vars; i++)
+ {
+ q = referenced_var (i);
+
+ if (POINTER_TYPE_P (TREE_TYPE (q))
+ && tag_set == get_alias_set (TREE_TYPE (TREE_TYPE (q))))
+ {
+ /* Found another pointer Q with the same alias set as
+ the PTR's pointed-to type. If Q has a type tag, use
+ it. Otherwise, create a new memory tag for PTR. */
+ var_ann_t ann1 = var_ann (q);
+ if (ann1->type_mem_tag)
+ ann->type_mem_tag = ann1->type_mem_tag;
+ else
+ ann->type_mem_tag = create_memory_tag (tag_type, true);
+ goto found_tag;
+ }
+ }
+
+ /* Couldn't find any other pointer with a type tag we could use.
+ Create a new memory tag for PTR. */
+ ann->type_mem_tag = create_memory_tag (tag_type, true);
+ }
+
+found_tag:
+ /* If VAR is not already PTR's type tag, add it to the may-alias set
+ for PTR's type tag. */
+ gcc_assert (var_ann (var)->type_mem_tag == NOT_A_TAG);
+ tag = ann->type_mem_tag;
+ add_may_alias (tag, var);
+
+ /* TAG and its set of aliases need to be marked for renaming. */
+ mark_sym_for_renaming (tag);
+ if ((aliases = var_ann (tag)->may_aliases) != NULL)
+ {
+ size_t i;
+ for (i = 0; i < VARRAY_ACTIVE_SIZE (aliases); i++)
+ mark_sym_for_renaming (VARRAY_TREE (aliases, i));
+ }
+
+ /* If we had grouped aliases, VAR may have aliases of its own. Mark
+ them for renaming as well. Other statements referencing the
+ aliases of VAR will need to be updated. */
+ if ((aliases = var_ann (var)->may_aliases) != NULL)
+ {
+ size_t i;
+ for (i = 0; i < VARRAY_ACTIVE_SIZE (aliases); i++)
+ mark_sym_for_renaming (VARRAY_TREE (aliases, i));
+ }
+}
+
+
/* This structure is simply used during pushing fields onto the fieldstack
to track the offset of the field, since bitpos_of_field gives it relative
to its immediate containing type, and we want it relative to the ultimate
@@ -3168,4 +3256,3 @@ struct tree_opt_pass pass_create_structure_vars =
TODO_dump_func, /* todo_flags_finish */
0 /* letter */
};
-
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