PR 17961

[pf3gnuchains/gcc-fork.git] / gcc / tree.c

diff --git a/gcc/tree.c b/gcc/tree.c
index 15488fb..2f5f924 100644 (file)
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -4937,9 +4937,16 @@ get_unwidened (tree op, tree for_type)
   while (TREE_CODE (op) == NOP_EXPR
         || TREE_CODE (op) == CONVERT_EXPR)
     {
-      int bitschange
-       = TYPE_PRECISION (TREE_TYPE (op))
-         - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
+      int bitschange;
+
+      /* TYPE_PRECISION on vector types has different meaning
+        (TYPE_VECTOR_SUBPARTS) and casts from vectors are view conversions,
+        so avoid them here.  */
+      if (TREE_CODE (TREE_TYPE (TREE_OPERAND (op, 0))) == VECTOR_TYPE)
+       break;
+
+      bitschange = TYPE_PRECISION (TREE_TYPE (op))
+                  - TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (op, 0)));
 
       /* Truncations are many-one so cannot be removed.
         Unless we are later going to truncate down even farther.  */