From: Richard Stallman <rms@gnu.org>
Date: Wed, 26 Aug 1992 06:04:35 +0000 (+0000)
Subject: (fold): Avoid the normal STRIP_NOPS on arg of NOP_EXPR.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=1b81aa149386d6b086c0a55837e9c34331f3bb27;p=gcc.git

(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 44933bf6869..e23683e2dcb 100644
--- 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;