From: ian <ian@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Fri, 2 Feb 2007 19:16:04 +0000 (+0000)
Subject: 	* expmed.c (expand_divmod): Add comment.
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=3d77819c1e9c627bb0c283cafbd88acfd77e87e4;p=thirdparty%2Fgcc.git

	* expmed.c (expand_divmod): Add comment.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@121519 138bc75d-0d04-0410-961f-82ee72b054a4
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 95987efeb569..38dd30edfe18 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,7 @@
+2007-02-02  Ian Lance Taylor  <iant@google.com>
+
+	* expmed.c (expand_divmod): Add comment.
+
 2007-02-02  Kazu Hirata  <kazu@codesourcery.com>
 
 	* emit-rtl.c (renumber_insns): Remove.
diff --git a/gcc/expmed.c b/gcc/expmed.c
index fea859a18c1e..8e8a63917a19 100644
--- a/gcc/expmed.c
+++ b/gcc/expmed.c
@@ -4176,6 +4176,9 @@ expand_divmod (int rem_flag, enum tree_code code, enum machine_mode mode,
 		HOST_WIDE_INT d = INTVAL (op1);
 		unsigned HOST_WIDE_INT abs_d;
 
+		/* Since d might be INT_MIN, we have to cast to
+		   unsigned HOST_WIDE_INT before negating to avoid
+		   undefined signed overflow.  */
 		abs_d = (d >= 0
 			 ? (unsigned HOST_WIDE_INT) d
 			 : - (unsigned HOST_WIDE_INT) d);