re PR tree-optimization/46349 (incorrect scalarization)

2010-11-15  Martin Jambor  <mjambor@suse.cz>

	PR tree-optimization/46349
	* tree-sra.c (contains_bitfld_comp_ref_p): New function.
	(contains_vce_or_bfcref_p): Likewise.
	(sra_modify_assign): Use them.

	* testsuite/gnat.dg/opt9.adb: New file.
	* testsuite/gnat.dg/opt9_pkg.ads: Likewise

From-SVN: r166759

gcc/ChangeLog

+2010-11-15  Martin Jambor  <mjambor@suse.cz>
+
+	PR tree-optimization/46349
+	* tree-sra.c (contains_bitfld_comp_ref_p): New function.
+	(contains_vce_or_bfcref_p): Likewise.
+	(sra_modify_assign): Use them.
+
 2010-11-15  Richard Guenther  <rguenther@suse.de>
 
 	PR tree-optimization/46467

gcc/testsuite/ChangeLog

+2010-11-15  Martin Jambor  <mjambor@suse.cz>
+
+	PR tree-optimization/46349
+	* gnat.dg/opt9.adb: New file.
+	* gnat.dg/opt9_pkg.ads: Likewise
+
 2010-11-15  Richard Guenther  <rguenther@suse.de>
 
 	PR lto/44989

gcc/testsuite/gnat.dg/opt9.adb

+-- { dg-do compile }
+-- { dg-options "-gnatws -O" }
+
+with Opt9_Pkg; use Opt9_Pkg;
+
+procedure Opt9 is
+
+   type Array_T is array (1 .. N) of Integer;
+
+   type Clock_T is record
+      N_Ticks : Integer := 0;
+   end record;
+
+   type Rec is record
+      Values : Array_T;
+      Valid  : Boolean;
+      Tstamp : Clock_T;
+   end record;
+
+   pragma Pack (Rec);
+
+   Data : Rec;
+
+begin
+   null;
+end;

gcc/testsuite/gnat.dg/opt9_pkg.ads

+package Opt9_Pkg is
+
+  N : integer := 15;
+
+end Opt9_Pkg;

gcc/tree-sra.c

@@ -2626,6 +2626,41 @@ get_repl_default_def_ssa_name (struct access *racc)
   return repl;
 }
 
+/* Return true if REF has a COMPONENT_REF with a bit-field field declaration
+   somewhere in it.  */
+
+static inline bool
+contains_bitfld_comp_ref_p (const_tree ref)
+{
+  while (handled_component_p (ref))
+    {
+      if (TREE_CODE (ref) == COMPONENT_REF
+          && DECL_BIT_FIELD (TREE_OPERAND (ref, 1)))
+        return true;
+      ref = TREE_OPERAND (ref, 0);
+    }
+
+  return false;
+}
+
+/* Return true if REF has an VIEW_CONVERT_EXPR or a COMPONENT_REF with a
+   bit-field field declaration somewhere in it.  */
+
+static inline bool
+contains_vce_or_bfcref_p (const_tree ref)
+{
+  while (handled_component_p (ref))
+    {
+      if (TREE_CODE (ref) == VIEW_CONVERT_EXPR
+	  || (TREE_CODE (ref) == COMPONENT_REF
+	      && DECL_BIT_FIELD (TREE_OPERAND (ref, 1))))
+	return true;
+      ref = TREE_OPERAND (ref, 0);
+    }
+
+  return false;
+}
+
 /* Examine both sides of the assignment statement pointed to by STMT, replace
    them with a scalare replacement if there is one and generate copying of
    replacements if scalarized aggregates have been used in the assignment.  GSI
@@ -2694,6 +2729,7 @@ sra_modify_assign (gimple *stmt, gimple_stmt_iterator *gsi)
 	     ???  This should move to fold_stmt which we simply should
 	     call after building a VIEW_CONVERT_EXPR here.  */
 	  if (AGGREGATE_TYPE_P (TREE_TYPE (lhs))
+	      && !contains_bitfld_comp_ref_p (lhs)
 	      && !access_has_children_p (lacc))
 	    {
 	      lhs = build_ref_for_offset (loc, lhs, 0, TREE_TYPE (rhs),
@@ -2701,7 +2737,7 @@ sra_modify_assign (gimple *stmt, gimple_stmt_iterator *gsi)
 	      gimple_assign_set_lhs (*stmt, lhs);
 	    }
 	  else if (AGGREGATE_TYPE_P (TREE_TYPE (rhs))
-		   && !contains_view_convert_expr_p (rhs)
+		   && !contains_vce_or_bfcref_p (rhs)
 		   && !access_has_children_p (racc))
 	    rhs = build_ref_for_offset (loc, rhs, 0, TREE_TYPE (lhs),
 					gsi, false);
@@ -2751,8 +2787,8 @@ sra_modify_assign (gimple *stmt, gimple_stmt_iterator *gsi)
      This is what the first branch does.  */
 
   if (gimple_has_volatile_ops (*stmt)
-      || contains_view_convert_expr_p (rhs)
-      || contains_view_convert_expr_p (lhs))
+      || contains_vce_or_bfcref_p (rhs)
+      || contains_vce_or_bfcref_p (lhs))
     {
       if (access_has_children_p (racc))
 	generate_subtree_copies (racc->first_child, racc->base, 0, 0, 0,