From: Richard Kenner <kenner@gcc.gnu.org>
Date: Sat, 26 Dec 1992 23:11:20 +0000 (-0500)
Subject: (gen_lowpart_for_combine): Allow MODE to be wider than a word in
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=eae957a8b8701537efa1af34a619971e5f81827e;p=gcc.git

(gen_lowpart_for_combine): Allow MODE to be wider than a word in
restricted circumstances.

From-SVN: r2914
---

diff --git a/gcc/combine.c b/gcc/combine.c
index 331e6ce8d07..360c81e5daf 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -7416,7 +7416,14 @@ gen_lowpart_for_combine (mode, x)
   if (GET_MODE (x) == mode)
     return x;
 
-  if (GET_MODE_SIZE (mode) > UNITS_PER_WORD)
+  /* We can only support MODE being wider than a word if X is a
+     constant integer or has a mode the same size.  */
+
+  if (GET_MODE_SIZE (mode) > UNITS_PER_WORD
+      && ! ((GET_MODE (x) == VOIDmode
+	     && (GET_CODE (x) == CONST_INT
+		 || GET_CODE (x) == CONST_DOUBLE))
+	    || GET_MODE_SIZE (GET_MODE (x)) == GET_MODE_SIZE (mode)))
     return gen_rtx (CLOBBER, GET_MODE (x), const0_rtx);
 
   /* X might be a paradoxical (subreg (mem)).  In that case, gen_lowpart