From: Richard Kenner <kenner@gcc.gnu.org>
Date: Mon, 16 May 1994 20:16:12 +0000 (-0400)
Subject: (convert_move): When {zero,sign}_extending, allow a wider intermediate
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=930b4e398ec14f8ea10acb0451655802ed4bb134;p=gcc.git

(convert_move): When {zero,sign}_extending, allow a wider intermediate
than to_mode if truncation is a no-op.

From-SVN: r7306
---

diff --git a/gcc/expr.c b/gcc/expr.c
index 38789ffecc9..f6317ee267d 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -1043,8 +1043,10 @@ convert_move (to, from, unsignedp)
 	  /* Search for a mode to convert via.  */
 	  for (intermediate = from_mode; intermediate != VOIDmode;
 	       intermediate = GET_MODE_WIDER_MODE (intermediate))
-	    if ((can_extend_p (to_mode, intermediate, unsignedp)
-		 != CODE_FOR_nothing)
+	    if (((can_extend_p (to_mode, intermediate, unsignedp)
+		  != CODE_FOR_nothing)
+		 || (GET_MODE_SIZE (to_mode) < GET_MODE_SIZE (intermediate)
+		     && TRULY_NOOP_TRUNCATION (to_mode, intermediate)))
 		&& (can_extend_p (intermediate, from_mode, unsignedp)
 		    != CODE_FOR_nothing))
 	      {