2008-01-16 Richard Guenther <rguenther@suse.de>

	PR tree-optimization/34769
	* tree-data-ref.c (initialize_matrix_A): Revert fix for PR34458.
	* tree.c (int_cst_value): Instead make this function more
	permissive in what it accepts as valid input.  Document this
	function always sign-extends the value.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@131573 138bc75d-0d04-0410-961f-82ee72b054a4

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 909008b..2d4f0c7 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2008-01-16  Richard Guenther  <rguenther@suse.de>
+
+       PR tree-optimization/34769
+       * tree-data-ref.c (initialize_matrix_A): Revert fix for PR34458.
+       * tree.c (int_cst_value): Instead make this function more
+       permissive in what it accepts as valid input.  Document this
+       function always sign-extends the value.
+
 2008-01-16  Jakub Jelinek  <jakub@redhat.com>
        Richard Guenther  <rguenther@suse.de>
 

diff --git a/gcc/tree-data-ref.c b/gcc/tree-data-ref.c
index 1fe7c0a..2f17ed1 100644 (file)
--- a/gcc/tree-data-ref.c
+++ b/gcc/tree-data-ref.c
@@ -1823,21 +1823,12 @@ analyze_siv_subscript_cst_affine (tree chrec_a,
 static HOST_WIDE_INT
 initialize_matrix_A (lambda_matrix A, tree chrec, unsigned index, int mult)
 {
-  tree type;
-
   gcc_assert (chrec);
 
-  type = TREE_TYPE (chrec);
   if (TREE_CODE (chrec) != POLYNOMIAL_CHREC)
-    return tree_low_cst (chrec, TYPE_UNSIGNED (type)
-                               && !(TREE_CODE (type) == INTEGER_TYPE
-                                    && TYPE_IS_SIZETYPE (type)));
-
-  type = TREE_TYPE (CHREC_RIGHT (chrec));
-  A[index][0] = mult * tree_low_cst (CHREC_RIGHT (chrec),
-                                    TYPE_UNSIGNED (type)
-                                    && !(TREE_CODE (type) == INTEGER_TYPE
-                                         && TYPE_IS_SIZETYPE (type)));
+    return int_cst_value (chrec);
+
+  A[index][0] = mult * int_cst_value (CHREC_RIGHT (chrec));
   return initialize_matrix_A (A, CHREC_LEFT (chrec), index + 1, mult);
 }
 

diff --git a/gcc/tree.c b/gcc/tree.c
index 02570b7..21121b2 100644 (file)
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -8036,21 +8036,26 @@ find_compatible_field (tree record, tree orig_field)
   return orig_field;
 }
 
-/* Return value of a constant X.  */
+/* Return value of a constant X and sign-extend it.  */
 
 HOST_WIDE_INT
 int_cst_value (const_tree x)
 {
   unsigned bits = TYPE_PRECISION (TREE_TYPE (x));
   unsigned HOST_WIDE_INT val = TREE_INT_CST_LOW (x);
-  bool negative = ((val >> (bits - 1)) & 1) != 0;
 
-  gcc_assert (bits <= HOST_BITS_PER_WIDE_INT);
+  /* Make sure the sign-extended value will fit in a HOST_WIDE_INT.  */
+  gcc_assert (TREE_INT_CST_HIGH (x) == 0
+             || TREE_INT_CST_HIGH (x) == -1);
 
-  if (negative)
-    val |= (~(unsigned HOST_WIDE_INT) 0) << (bits - 1) << 1;
-  else
-    val &= ~((~(unsigned HOST_WIDE_INT) 0) << (bits - 1) << 1);
+  if (bits < HOST_BITS_PER_WIDE_INT)
+    {
+      bool negative = ((val >> (bits - 1)) & 1) != 0;
+      if (negative)
+       val |= (~(unsigned HOST_WIDE_INT) 0) << (bits - 1) << 1;
+      else
+       val &= ~((~(unsigned HOST_WIDE_INT) 0) << (bits - 1) << 1);
+    }
 
   return val;
 }