gimple-fold.c (fold_gimple_assign): Remove operand swapping.

2011-07-14  Richard Guenther  <rguenther@suse.de>

	* gimple-fold.c (fold_gimple_assign): Remove operand swapping.
	(fold_stmt_1): Do it here directly on gimple and as a first thing.

From-SVN: r176273

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 61b45357296095cfcabf4607103674e76f02a07a..869214d5836f48388e5c9ea8f7fb54bc1bf50a9a 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2011-07-14  Richard Guenther  <rguenther@suse.de>
+
+       * gimple-fold.c (fold_gimple_assign): Remove operand swapping.
+       (fold_stmt_1): Do it here directly on gimple and as a first thing.
+
 2011-07-14  Richard Guenther  <rguenther@suse.de>
 
        * fold-const.c (fold_binary_loc): Convert the !bool_var result,

diff --git a/gcc/gimple-fold.c b/gcc/gimple-fold.c
index 6b3b275eeee652a25277a609424712f8a12f1b3f..bf00a0f04604013a2c3205b04fd9b1bcf4f2993d 100644 (file)
--- a/gcc/gimple-fold.c
+++ b/gcc/gimple-fold.c
@@ -817,26 +817,15 @@ fold_gimple_assign (gimple_stmt_iterator *si)
 
       if (!result)
         result = fold_binary_loc (loc, subcode,
-                              TREE_TYPE (gimple_assign_lhs (stmt)),
-                              gimple_assign_rhs1 (stmt),
-                              gimple_assign_rhs2 (stmt));
+                                 TREE_TYPE (gimple_assign_lhs (stmt)),
+                                 gimple_assign_rhs1 (stmt),
+                                 gimple_assign_rhs2 (stmt));
 
       if (result)
         {
           STRIP_USELESS_TYPE_CONVERSION (result);
           if (valid_gimple_rhs_p (result))
            return result;
-
-         /* Fold might have produced non-GIMPLE, so if we trust it blindly
-            we lose canonicalization opportunities.  Do not go again
-            through fold here though, or the same non-GIMPLE will be
-            produced.  */
-          if (commutative_tree_code (subcode)
-              && tree_swap_operands_p (gimple_assign_rhs1 (stmt),
-                                       gimple_assign_rhs2 (stmt), false))
-            return build2 (subcode, TREE_TYPE (gimple_assign_lhs (stmt)),
-                           gimple_assign_rhs2 (stmt),
-                           gimple_assign_rhs1 (stmt));
         }
       break;
 
@@ -852,18 +841,6 @@ fold_gimple_assign (gimple_stmt_iterator *si)
           STRIP_USELESS_TYPE_CONVERSION (result);
           if (valid_gimple_rhs_p (result))
            return result;
-
-         /* Fold might have produced non-GIMPLE, so if we trust it blindly
-            we lose canonicalization opportunities.  Do not go again
-            through fold here though, or the same non-GIMPLE will be
-            produced.  */
-          if (commutative_ternary_tree_code (subcode)
-              && tree_swap_operands_p (gimple_assign_rhs1 (stmt),
-                                       gimple_assign_rhs2 (stmt), false))
-            return build3 (subcode, TREE_TYPE (gimple_assign_lhs (stmt)),
-                          gimple_assign_rhs2 (stmt),
-                          gimple_assign_rhs1 (stmt),
-                          gimple_assign_rhs3 (stmt));
         }
       break;
 
@@ -1576,8 +1553,22 @@ fold_stmt_1 (gimple_stmt_iterator *gsi, bool inplace)
     case GIMPLE_ASSIGN:
       {
        unsigned old_num_ops = gimple_num_ops (stmt);
-       tree new_rhs = fold_gimple_assign (gsi);
+       enum tree_code subcode = gimple_assign_rhs_code (stmt);
        tree lhs = gimple_assign_lhs (stmt);
+       tree new_rhs;
+       /* First canonicalize operand order.  This avoids building new
+          trees if this is the only thing fold would later do.  */
+       if ((commutative_tree_code (subcode)
+            || commutative_ternary_tree_code (subcode))
+           && tree_swap_operands_p (gimple_assign_rhs1 (stmt),
+                                    gimple_assign_rhs2 (stmt), false))
+         {
+           tree tem = gimple_assign_rhs1 (stmt);
+           gimple_assign_set_rhs1 (stmt, gimple_assign_rhs2 (stmt));
+           gimple_assign_set_rhs2 (stmt, tem);
+           changed = true;
+         }
+       new_rhs = fold_gimple_assign (gsi);
        if (new_rhs
            && !useless_type_conversion_p (TREE_TYPE (lhs),
                                           TREE_TYPE (new_rhs)))