tree.h (categorize_ctor_elements): Adjust prototype and add descriptive comment...

	* tree.h (categorize_ctor_elements): Adjust prototype and add
	descriptive comment, both in accordance with the interface change
	described below.
	* varasm.c (constructor_static_from_elts_p): New function.
	Whether a constructor node is a valid static constant initializer
	if all its elements are.
	(initializer_constant_valid_p) <CONSTRUCTOR value>: Use it.
	* output.h: Declare it.	
	* expr.c (categorize_ctor_elements_1): Return whether the constructor
	is a valid constant initializer instead of computing the number of
	non-constant elements.  Use constructor_static_from_elts_p for this
	purpose.  Replace the head comment with an indication that this is a
	helper for categorize_ctor_elements.
	(categorize_ctor_elements): Same interface change as for the _1
	helper.  Former head comment from this helper moved here, adjusted to
	account for the interface changes.
	(mostly_zeros_p): Adjust call to categorize_ctor_elements.
	(all_zeros_p): Likewise.	
	* gimplify.c (gimplify_init_constructor): Decide whether we can make
	static versions of the constructor from the categorize_ctor_elements
	return value instead of the formerly computed number of non-constant
	elements.

	* gnat.dg/outer_agg_bitfield_constructor.adb: New test.
	* gnat.dg/nested_agg_bitfield_constructor.adb: New test.

From-SVN: r115553

1 files changed, 10 insertions, 7 deletions

diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index a5e7e66..16e4d3c 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -2940,8 +2940,8 @@ gimplify_init_constructor (tree *expr_p, tree *pre_p,
       {
 	struct gimplify_init_ctor_preeval_data preeval_data;
 	HOST_WIDE_INT num_type_elements, num_ctor_elements;
-	HOST_WIDE_INT num_nonzero_elements, num_nonconstant_elements;
-	bool cleared;
+	HOST_WIDE_INT num_nonzero_elements;
+	bool cleared, valid_const_initializer;
 
 	/* Aggregate types must lower constructors to initialization of
 	   individual elements.  The exception is that a CONSTRUCTOR node
@@ -2949,13 +2949,16 @@ gimplify_init_constructor (tree *expr_p, tree *pre_p,
 	if (VEC_empty (constructor_elt, elts))
 	  break;
 
-	categorize_ctor_elements (ctor, &num_nonzero_elements,
-				  &num_nonconstant_elements,
-				  &num_ctor_elements, &cleared);
+	/* Fetch information about the constructor to direct later processing.
+	   We might want to make static versions of it in various cases, and
+	   can only do so if it known to be a valid constant initializer.  */
+	valid_const_initializer
+	  = categorize_ctor_elements (ctor, &num_nonzero_elements,
+				      &num_ctor_elements, &cleared);
 
 	/* If a const aggregate variable is being initialized, then it
 	   should never be a lose to promote the variable to be static.  */
-	if (num_nonconstant_elements == 0
+	if (valid_const_initializer
 	    && num_nonzero_elements > 1
 	    && TREE_READONLY (object)
 	    && TREE_CODE (object) == VAR_DECL)
@@ -3012,7 +3015,7 @@ gimplify_init_constructor (tree *expr_p, tree *pre_p,
 	   for sparse arrays, though, as it's more efficient to follow
 	   the standard CONSTRUCTOR behavior of memset followed by
 	   individual element initialization.  */
-	if (num_nonconstant_elements == 0 && !cleared)
+	if (valid_const_initializer && !cleared)
 	  {
 	    HOST_WIDE_INT size = int_size_in_bytes (type);
 	    unsigned int align;