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From: "pinskia at gcc dot gnu dot org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/41868] cell microcode instruction (addic.) is generated for a trivial loop with -O2 optimizations, hurting performance badly
Date: Mon, 02 Nov 2009 17:09:00 -0000	[thread overview]
Message-ID: <20091102170854.11224.qmail@sourceware.org> (raw)
In-Reply-To: <bug-41868-14457@http.gcc.gnu.org/bugzilla/>



------- Comment #5 from pinskia at gcc dot gnu dot org  2009-11-02 17:08 -------
In fact doing the following diff to the -Os assembly:
--- t5.Os.s     2009-11-02 23:18:52.000000000 +0900
+++ t5.Os.dot.s 2009-11-02 23:20:19.000000000 +0900
@@ -29,9 +29,9 @@ x:
 .L4:
        bl y
 .L3:
-       cmpwi 7,31,0
-       addi 31,31,-1
-       bne 7,.L4
+#      cmpwi 7,31,0
+       addic. 31,31,-1
+       bne .L4
        addi 11,1,16
        b _restgpr_31_x
        .size   x,.-x

produces the same result as -Os on the trunk.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41868


  parent reply	other threads:[~2009-11-02 17:09 UTC|newest]

Thread overview: 10+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-10-29 15:16 [Bug target/41868] New: cell microcode instruction " siarhei dot siamashka at gmail dot com
2009-10-29 15:21 ` [Bug target/41868] cell microcode instruction (addic.) " siarhei dot siamashka at gmail dot com
2009-11-02 16:51 ` pinskia at gcc dot gnu dot org
2009-11-02 16:56 ` pinskia at gcc dot gnu dot org
2009-11-02 17:05 ` pinskia at gcc dot gnu dot org
2009-11-02 17:09 ` pinskia at gcc dot gnu dot org [this message]
2009-11-02 17:10 ` pinskia at gcc dot gnu dot org
2009-11-03 20:09 ` siarhei dot siamashka at gmail dot com
     [not found] <bug-41868-4@http.gcc.gnu.org/bugzilla/>
2011-11-29 23:21 ` pinskia at gcc dot gnu.org
2011-11-29 23:28 ` pinskia at gcc dot gnu.org

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