tree-ssa-forwprop.c (simplify_bitwise_binary): Improve type sinking.

2011-06-28  Kai Tietz  <ktietz@redhat.com>

        * tree-ssa-forwprop.c (simplify_bitwise_binary): Improve
        type sinking.

From-SVN: r175589

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 23997c43a41bbad0e7645a052ff0b9442385f660..60bc9c65b9a73b43851ff447f77a5cb53ac67368 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2011-06-28  Kai Tietz  <ktietz@redhat.com>
+
+       * tree-ssa-forwprop.c (simplify_bitwise_binary): Improve
+       type sinking.
+
 2011-06-28  Ramana Radhakrishnan  <ramana.radhakrishnan@linaro.org>
 
        * config/arm/vfp.md ("*divsf3_vfp"): Replace '+' constraint modifier

diff --git a/gcc/tree-ssa-forwprop.c b/gcc/tree-ssa-forwprop.c
index 86f45021229501a808bc9f1c3e97c200c8232bf0..27453dd9720e023128fe52075172c8c5dbbdadfe 100644 (file)
--- a/gcc/tree-ssa-forwprop.c
+++ b/gcc/tree-ssa-forwprop.c
@@ -1676,16 +1676,39 @@ simplify_bitwise_binary (gimple_stmt_iterator *gsi)
        }
     }
 
+  /* Try to fold (type) X op CST -> (type) (X op ((type-x) CST)).  */
+  if (TREE_CODE (arg2) == INTEGER_CST
+      && CONVERT_EXPR_CODE_P (def1_code)
+      && INTEGRAL_TYPE_P (def1_arg1)
+      && int_fits_type_p (arg2, TREE_TYPE (def1_arg1)))
+    {
+      gimple newop;
+      tree tem = create_tmp_reg (TREE_TYPE (def1_arg1), NULL);
+      newop =
+        gimple_build_assign_with_ops (code, tem, def1_arg1,
+                                     fold_convert_loc (gimple_location (stmt),
+                                                       TREE_TYPE (def1_arg1),
+                                                       arg2));
+      tem = make_ssa_name (tem, newop);
+      gimple_assign_set_lhs (newop, tem);
+      gsi_insert_before (gsi, newop, GSI_SAME_STMT);
+      gimple_assign_set_rhs_with_ops_1 (gsi, NOP_EXPR,
+                                       tem, NULL_TREE, NULL_TREE);
+      update_stmt (gsi_stmt (*gsi));
+      return true;
+    }
+
   /* For bitwise binary operations apply operand conversions to the
      binary operation result instead of to the operands.  This allows
      to combine successive conversions and bitwise binary operations.  */
   if (CONVERT_EXPR_CODE_P (def1_code)
       && CONVERT_EXPR_CODE_P (def2_code)
       && types_compatible_p (TREE_TYPE (def1_arg1), TREE_TYPE (def2_arg1))
-      /* Make sure that the conversion widens the operands or that it
-        changes the operation to a bitfield precision.  */
+      /* Make sure that the conversion widens the operands, or has same
+        precision,  or that it changes the operation to a bitfield
+        precision.  */
       && ((TYPE_PRECISION (TREE_TYPE (def1_arg1))
-          < TYPE_PRECISION (TREE_TYPE (arg1)))
+          <= TYPE_PRECISION (TREE_TYPE (arg1)))
          || (GET_MODE_CLASS (TYPE_MODE (TREE_TYPE (arg1)))
              != MODE_INT)
          || (TYPE_PRECISION (TREE_TYPE (arg1))