In gcc/ada/

2005-03-12  Daniel Berlin <dberlin@dberlin.org>

	* misc.c (gnat_post_options): Turn off structural
	aliasing for now.
In gcc/
2005-03-12  Daniel Berlin  <dberlin@dberlin.org>

	* tree-flow-inline.h (ref_contains_array_ref): New function.
	(lookup_subvars_for_var): Ditto.
	(get_subvars_for_var): Ditto.
	(var_can_have_subvars): Ditto.

	* tree-flow.h (mem_tag_kind): Add STRUCT_FIELD.
	(struct subvar): New type.

	* tree-dfa.c (okay_component_ref_for_subvars): New function.

	* tree-optimize.c (init_tree_optimization_passes): Call
	pass_create_structure_vars.

	* tree-ssa-alias.c: Include vec.h.
	(init_alias_info): Don't auto-clear call clobbered on struct-field
	tags.
	(compute_flow_insensitive_aliasing): Handle subvars.
	(group_aliases): Handle STRUCT_FIELD aliases.
	(setup_pointers_and_addressables): Ditto.
	Don't mark variables non-addressable if they still have
	addressable subvars.
	Also mark subvars addressable when the real variable is marked
	addressable.
	(add_pointed_to_var): Try to prune the pointed-to set by only
	pointing to subvars when possible.
	Otherwise, make sure we set addresses_needed and pt_vars to
	properly include subvars.
	(bitpos_of_field): New function.
	(push_fields_onto_fieldstack): Ditto.
	(get_or_create_used_part_for): Ditto.
	(create_overlap_variables_for): Ditto.
	(find_used_portions): Ditto.
	(create_structure_vars): Ditto.
	(pass_create_structure_vars): New structure.

	* tree-ssa-operands.c (finalize_ssa_v_must_defs): Remove assert.
	(get_expr_operands): Handle subvars.  Also try to turn
	COMPONENT_REF accesses into must-defs now that we can accurately
	portray it.
	(note_addressable): Try to only mark as addressable those subvars
	we know a COMPONENT_REF touches.
	(overlap_subvar): New function.

	* tree-vect-analyze.c (vect_object_analysis): Add new parameter.
	Handle subvar storing.
	(vect_address_analysis): Update caller of vect_object_analysis.

	* tree-vect-transform.c (vect_create_data_ref_ptr): Copy subvars.

	* tree-vectorizer.h (struct _stmt_vec_info): Add subvars member.
	(STMT_VINFO_SUBVARS): New macro.

	* common.opts: add flag_tree_salias.

	* opts.c (decode_options): flag_tree_salias defaults to on.

	* doc/invoke.texi: Document fdump-tree-svars and -ftree-salias.

	* doc/tree-ssa.texi: Document structural alias analysis.


git-svn-id: https://gcc.gnu.org/svn/gcc/trunk@96362 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 43 insertions, 0 deletions

diff --git a/gcc/tree-dfa.c b/gcc/tree-dfa.c
index 630ee4cbf8d..6bbec8f8d1e 100644
--- a/gcc/tree-dfa.c
+++ b/gcc/tree-dfa.c
@@ -1053,3 +1053,46 @@ mark_call_clobbered_vars_to_rename (void)
       bitmap_set_bit (vars_to_rename, var_ann (var)->uid);
     }
 }
+
+/* If REF is a COMPONENT_REF for a structure that can have sub-variables, and
+   we know where REF is accessing, return the variable in REF that has the
+   sub-variables.  If the return value is not NULL, POFFSET will be the
+   offset, in bits, of REF inside the return value, and PSIZE will be the
+   size, in bits, of REF inside the return value.  */
+
+tree
+okay_component_ref_for_subvars (tree ref, HOST_WIDE_INT *poffset,
+				HOST_WIDE_INT *psize)
+{
+  tree result = NULL;
+  HOST_WIDE_INT bitsize;
+  HOST_WIDE_INT bitpos;
+  tree offset;
+  enum machine_mode mode;
+  int unsignedp;
+  int volatilep;
+
+  gcc_assert (!SSA_VAR_P (ref));
+  *poffset = 0;  
+  *psize = (unsigned int) -1;
+  
+  if (ref_contains_array_ref (ref))
+    return result;
+  ref = get_inner_reference (ref, &bitsize, &bitpos, &offset, &mode,
+			     &unsignedp, &volatilep, false);
+  if (TREE_CODE (ref) == INDIRECT_REF)
+    return result;
+  else if (offset == NULL && bitsize != -1 && SSA_VAR_P (ref))
+    {
+      *poffset = bitpos;      
+      *psize = bitsize;
+      if (get_subvars_for_var (ref) != NULL)
+	return ref;
+    }
+  else if (SSA_VAR_P (ref))
+    {
+      if (get_subvars_for_var (ref) != NULL)
+	return ref;
+    }
+  return NULL_TREE;
+}