From: Jakub Jelinek <jakub@redhat.com>
Date: Tue, 17 Dec 2002 13:52:38 +0000 (+0100)
Subject: re PR rtl-optimization/8794 (optimization improperly eliminates certain expressions)
X-Git-Tag: releases/gcc-3.2.2~171
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a9d164caa08e6d11e68ae8ce761348a99b4a8640;p=thirdparty%2Fgcc.git

re PR rtl-optimization/8794 (optimization improperly eliminates certain expressions)

	PR opt/8794
	* combine.c (force_to_mode) [MINUS]: Only replace with (not Y) if all
	bits in fuller_mask (not just mask) are set in C.

	* gcc.c-torture/execute/20021118-3.c: New test.

From-SVN: r60210
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 624ff10ef13a..49962b81341d 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,9 @@
+2002-12-17  Jakub Jelinek  <jakub@redhat.com>
+
+	PR opt/8794
+	* combine.c (force_to_mode) [MINUS]: Only replace with (not Y) if all
+	bits in fuller_mask (not just mask) are set in C.
+
 2002-12-12  John David Anglin  <dave@hiauly1.hia.nrc.ca>
 
 	* pa.h (BIGGEST_ALIGNMENT): Change 32-bit value to 64 bits.
diff --git a/gcc/combine.c b/gcc/combine.c
index 65564d98310d..5e8ad1ac3a28 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -6857,10 +6857,10 @@ force_to_mode (x, mode, mask, reg, just_select)
 	  return force_to_mode (x, mode, mask, reg, next_select);
 	}
 
-      /* Similarly, if C contains every bit in the mask, then we may
+      /* Similarly, if C contains every bit in the fuller_mask, then we may
 	 replace with (not Y).  */
       if (GET_CODE (XEXP (x, 0)) == CONST_INT
-	  && ((INTVAL (XEXP (x, 0)) | (HOST_WIDE_INT) mask)
+	  && ((INTVAL (XEXP (x, 0)) | (HOST_WIDE_INT) fuller_mask)
 	      == INTVAL (XEXP (x, 0))))
 	{
 	  x = simplify_gen_unary (NOT, GET_MODE (x),
diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 09d09e28fcaf..bb479eca3dc0 100644
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,3 +1,7 @@
+2002-12-17  Jakub Jelinek  <jakub@redhat.com>
+
+	* gcc.c-torture/execute/20021118-3.c: New test.
+
 2002-12-12  Eric Botcazou  <ebotcazou@libertysurf.fr>
 
 	* gcc.c-torture/compile/20021212-1.c: New test.