PR tree-optimization/15784

        * fold-const.c (fold): Fold ~A + 1 to -A.  Fold -A - 1
        and -1 - A to ~A.

        * stmt.c (expand_case): Don't change index_type.  Convert minval
        to the proper type.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@96289 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 82d61aa..8f21dbb 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,12 @@
 2005-03-11  James A. Morrison  <phython@gcc.gnu.org>
 
+        PR tree-optimization/15784
+        * fold-const.c (fold): Fold ~A + 1 to -A.  Fold -A - 1
+        and -1 - A to ~A.
+
+        * stmt.c (expand_case): Don't change index_type.  Convert minval
+        to the proper type.
+
        PR tree-optimization/20130
        * fold-const.c (fold): Fold x * -1 into -x.
 
@@ -722,7 +729,7 @@
        Revert for now:
        2005-03-03  James A. Morrison  <phython@gcc.gnu.org>
        PR tree-optimization/15784
-       * fold-const.c (fold): Fold ~A + 1 to -1.  Fold -A - 1
+       * fold-const.c (fold): Fold ~A + 1 to -A.  Fold -A - 1
        and -1 - A to ~A.
 
 2005-03-04  Ben Elliston  <bje@au.ibm.com>
@@ -756,7 +763,7 @@
 2005-03-03  James A. Morrison  <phython@gcc.gnu.org>
 
        PR tree-optimization/15784
-       * fold-const.c (fold): Fold ~A + 1 to -1.  Fold -A - 1
+       * fold-const.c (fold): Fold ~A + 1 to -A.  Fold -A - 1
        and -1 - A to ~A.
 
 2005-03-03  David Edelsohn  <edelsohn@gnu.org>

diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 9d0a9f0..3fdfb92 100644 (file)
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -7198,6 +7198,11 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1)
       if (TREE_CODE (arg0) == NEGATE_EXPR
          && reorder_operands_p (TREE_OPERAND (arg0, 0), arg1))
        return fold (build2 (MINUS_EXPR, type, arg1, TREE_OPERAND (arg0, 0)));
+      /* Convert ~A + 1 to -A.  */
+      if (INTEGRAL_TYPE_P (type)
+         && TREE_CODE (arg0) == BIT_NOT_EXPR
+         && integer_onep (arg1))
+       return fold (build1 (NEGATE_EXPR, type, TREE_OPERAND (arg0, 0)));
 
       if (TREE_CODE (type) == COMPLEX_TYPE)
        {
@@ -7636,6 +7641,16 @@ fold_binary (enum tree_code code, tree type, tree op0, tree op1)
          && reorder_operands_p (arg0, arg1))
        return fold (build2 (MINUS_EXPR, type, negate_expr (arg1),
                             TREE_OPERAND (arg0, 0)));
+      /* Convert -A - 1 to ~A.  */
+      if (INTEGRAL_TYPE_P (type)
+         && TREE_CODE (arg0) == NEGATE_EXPR
+         && integer_onep (arg1))
+       return fold (build1 (BIT_NOT_EXPR, type, TREE_OPERAND (arg0, 0)));
+
+      /* Convert -1 - A to ~A.  */
+      if (INTEGRAL_TYPE_P (type)
+         && integer_all_onesp (arg0))
+       return fold (build1 (BIT_NOT_EXPR, type, arg1));
 
       if (TREE_CODE (type) == COMPLEX_TYPE)
        {

diff --git a/gcc/stmt.c b/gcc/stmt.c
index a23c23c..9a1df90 100644 (file)
--- a/gcc/stmt.c
+++ b/gcc/stmt.c
@@ -2424,7 +2424,7 @@ expand_case (tree exp)
          if (compare_tree_int (minval, 0) > 0
              && compare_tree_int (maxval, GET_MODE_BITSIZE (word_mode)) < 0)
            {
-             minval = integer_zero_node;
+             minval = fold_convert (index_type, integer_zero_node);
              range = maxval;
            }
          emit_case_bit_tests (index_type, index_expr, minval, range,
@@ -2502,7 +2502,6 @@ expand_case (tree exp)
                            table_label, default_label))
            {
              bool ok;
-             index_type = integer_type_node;
 
              /* Index jumptables from zero for suitable values of
                  minval to avoid a subtraction.  */
@@ -2510,7 +2509,7 @@ expand_case (tree exp)
                  && compare_tree_int (minval, 0) > 0
                  && compare_tree_int (minval, 3) < 0)
                {
-                 minval = integer_zero_node;
+                 minval = fold_convert (index_type, integer_zero_node);
                  range = maxval;
                }