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From: "ubizjak at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/53346] [4.6/4.7/4.8 Regression] Bad vectorization in the proc cptrf2 of rnflow.f90
Date: Fri, 18 May 2012 17:46:00 -0000 [thread overview]
Message-ID: <bug-53346-4-ef11EYcYfH@http.gcc.gnu.org/bugzilla/> (raw)
In-Reply-To: <bug-53346-4@http.gcc.gnu.org/bugzilla/>
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53346
Uros Bizjak <ubizjak at gmail dot com> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |hjl.tools at gmail dot com
--- Comment #14 from Uros Bizjak <ubizjak at gmail dot com> 2012-05-18 17:17:45 UTC ---
Compile and execute slow assembly:
gfortran rnflow.s && time ./a.out
real 0m24.454s
user 0m24.167s
sys 0m0.231s
Apply following patch that changes cmove in very fast loops (cptrf2) to jumps:
--cut here--
--- rnflow.s 2012-05-18 19:00:22.314102061 +0200
+++ rnflow1.s 2012-05-18 19:10:59.363428625 +0200
@@ -1305,7 +1305,9 @@
movslq %edx, %rbx
movss -4(%rdi,%rbx,4), %xmm0
ucomiss (%r9), %xmm0
- cmova %ecx, %edx
+ jbe .L183x
+ movl %ecx, %edx
+.L183x:
subl $1, %ecx
subq $4, %r9
cmpl %r10d, %ecx
@@ -1329,7 +1331,9 @@
movslq %ecx, %r10
movss -4(%rdi,%r10,4), %xmm0
ucomiss (%r9), %xmm0
- cmova %r11d, %ecx
+ jbe .L192x
+ movl %r11d, %ecx
+.L192x:
subl $1, %r11d
subq $4, %r9
cmpl %eax, %r11d
@@ -1485,7 +1489,9 @@
movslq %edx, %r10
movss -4(%rdi,%r10,4), %xmm0
ucomiss (%r9), %xmm0
- cmova %ecx, %edx
+ jbe .L179x
+ movl %ecx, %edx
+.L179x:
subq $4, %r9
subl $1, %ecx
jne .L179
--cut here--
gfortran rnflow.s && time ./a.out
real 0m18.170s
user 0m17.907s
sys 0m0.223s
WTF happened here?!
Relevant part of my /proc/cpuinfo:
vendor_id : GenuineIntel
cpu family : 6
model : 42
Adding CC.
next prev parent reply other threads:[~2012-05-18 17:46 UTC|newest]
Thread overview: 27+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-05-14 15:44 [Bug tree-optimization/53346] New: " dominiq at lps dot ens.fr
2012-05-15 9:54 ` [Bug tree-optimization/53346] " rguenth at gcc dot gnu.org
2012-05-15 12:55 ` dominiq at lps dot ens.fr
2012-05-17 18:35 ` ubizjak at gmail dot com
2012-05-17 20:47 ` ubizjak at gmail dot com
2012-05-18 11:49 ` rguenth at gcc dot gnu.org
2012-05-18 14:28 ` rguenth at gcc dot gnu.org
2012-05-18 14:32 ` rguenth at gcc dot gnu.org
2012-05-18 14:49 ` ubizjak at gmail dot com
2012-05-18 14:52 ` dominiq at lps dot ens.fr
2012-05-18 15:13 ` ubizjak at gmail dot com
2012-05-18 17:32 ` ubizjak at gmail dot com
2012-05-18 17:34 ` ubizjak at gmail dot com
2012-05-18 17:46 ` ubizjak at gmail dot com [this message]
2012-05-18 17:48 ` ubizjak at gmail dot com
2012-05-18 17:56 ` pinskia at gcc dot gnu.org
2012-05-18 18:27 ` ubizjak at gmail dot com
2012-05-18 18:27 ` hjl.tools at gmail dot com
2012-05-18 19:45 ` dominiq at lps dot ens.fr
2012-05-19 23:50 ` dominiq at lps dot ens.fr
2012-09-07 11:59 ` [Bug target/53346] " rguenth at gcc dot gnu.org
2012-11-14 22:19 ` hubicka at gcc dot gnu.org
2012-11-14 22:38 ` hubicka at gcc dot gnu.org
2012-12-31 9:20 ` [Bug target/53346] [4.6/4.7/4.8 Regression] Bad if conversion in " pinskia at gcc dot gnu.org
2012-12-31 9:41 ` pinskia at gcc dot gnu.org
2022-09-26 3:22 ` cvs-commit at gcc dot gnu.org
2022-09-26 3:24 ` crazylht at gmail dot com
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