From: Richard Stallman <rms@gnu.org>
Date: Sat, 31 Oct 1992 21:16:47 +0000 (+0000)
Subject: (simplify_shift_const):
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=f9e67232ef84bdb81faf1f70359c5d6f2ffcc2e9;p=gcc.git

(simplify_shift_const):

For a subreg, require subreg_lowpart_p and not paradoxical.

From-SVN: r2664
---

diff --git a/gcc/combine.c b/gcc/combine.c
index 51835084b9a..3f90edb926d 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -6792,7 +6792,9 @@ simplify_shift_const (x, code, result_mode, varop, count)
 	  /* If VAROP is a SUBREG, strip it as long as the inner operand has
 	     the same number of words as what we've seen so far.  Then store
 	     the widest mode in MODE.  */
-	  if (SUBREG_WORD (varop) == 0
+	  if (subreg_lowpart_p (varop)
+	      && (GET_MODE_SIZE (GET_MODE (SUBREG_REG (varop)))
+		  > GET_MODE_SIZE (GET_MODE (varop)))
 	      && (((GET_MODE_SIZE (GET_MODE (SUBREG_REG (varop)))
 		    + (UNITS_PER_WORD - 1)) / UNITS_PER_WORD)
 		  == mode_words))