re PR tree-optimization/17474 (Compiling at -01 yields different results)

	PR tree-optimization/17474
	* tree-ssa-ccp.c (maybe_fold_offset_to_component_ref): Determine
	offset of the field correctly when DECL_FIELD_BIT_OFFSET != 0.

From-SVN: r88095

gcc/ChangeLog

+2004-09-25  Zdenek Dvorak  <rakdver@atrey.karlin.mff.cuni.cz>
+
+	PR tree-optimization/17474
+	* tree-ssa-ccp.c (maybe_fold_offset_to_component_ref): Determine
+	offset of the field correctly when DECL_FIELD_BIT_OFFSET != 0.
+
 2004-09-25  Jan Hubicka  <jh@suse.cz>
 
-	* predict.c (counts_to_freqs): Make glolbal.
+	* predict.c (counts_to_freqs): Make global.
 	* predict.h (counts_to_freqa): Declare.
 	* profile.c (compute_branch_probabilities): Compute frequencies
 	* tree-profile.c (do_tree_profiling): Refine conditional on when

gcc/tree-ssa-ccp.c

@@ -1395,7 +1395,7 @@ static tree
 maybe_fold_offset_to_component_ref (tree record_type, tree base, tree offset,
 				    tree orig_type, bool base_is_ptr)
 {
-  tree f, t, field_type, tail_array_field;
+  tree f, t, field_type, tail_array_field, field_offset;
 
   if (TREE_CODE (record_type) != RECORD_TYPE
       && TREE_CODE (record_type) != UNION_TYPE
@@ -1415,7 +1415,9 @@ maybe_fold_offset_to_component_ref (tree record_type, tree base, tree offset,
 	continue;
       if (DECL_BIT_FIELD (f))
 	continue;
-      if (TREE_CODE (DECL_FIELD_OFFSET (f)) != INTEGER_CST)
+
+      field_offset = byte_position (f);
+      if (TREE_CODE (field_offset) != INTEGER_CST)
 	continue;
 
       /* ??? Java creates "interesting" fields for representing base classes.
@@ -1428,7 +1430,7 @@ maybe_fold_offset_to_component_ref (tree record_type, tree base, tree offset,
       tail_array_field = NULL_TREE;
 
       /* Check to see if this offset overlaps with the field.  */
-      cmp = tree_int_cst_compare (DECL_FIELD_OFFSET (f), offset);
+      cmp = tree_int_cst_compare (field_offset, offset);
       if (cmp > 0)
 	continue;