(fold): Avoid the normal STRIP_NOPS on arg of NOP_EXPR.

From-SVN: r1959

diff --git a/gcc/fold-const.c b/gcc/fold-const.c
index 44933bf686916a686c136e214391053fc9d15385..e23683e2dcb8586af79e747a6fedc653c55dfc88 100644 (file)
--- a/gcc/fold-const.c
+++ b/gcc/fold-const.c
@@ -2849,7 +2849,27 @@ fold (expr)
     }
   
   kind = TREE_CODE_CLASS (code);
-  if (kind == 'e' || kind == '<' || kind == '1' || kind == '2' || kind == 'r')
+  if (code == NOP_EXPR || code == FLOAT_EXPR || code == CONVERT_EXPR)
+    {
+      /* Special case for conversion ops that can have fixed point args.  */
+      arg0 = TREE_OPERAND (t, 0);
+
+      /* Don't use STRIP_NOPS, because signedness of argument type matters.  */
+      if (arg0 != 0)
+       STRIP_TYPE_NOPS (arg0);
+
+      if (arg0 != 0 && TREE_CODE (arg0) != INTEGER_CST
+#if ! defined (REAL_IS_NOT_DOUBLE) || defined (REAL_ARITHMETIC)
+         && TREE_CODE (arg0) != REAL_CST
+#endif /* not REAL_IS_NOT_DOUBLE, or REAL_ARITHMETIC */
+         )
+       /* Note that TREE_CONSTANT isn't enough:
+          static var addresses are constant but we can't
+          do arithmetic on them.  */
+       wins = 0;
+    }
+  else if (kind == 'e' || kind == '<'
+          || kind == '1' || kind == '2' || kind == 'r')
     {
       register int len = tree_code_length[(int) code];
       register int i;