http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50182
--- Comment #11 from Oleg Smolsky 2011-08-26
00:48:02 UTC ---
Also, I have just built the same suite with GCC version 4.7 that came from
ftp://gcc.gnu.org/pub/gcc/snapshots/4.7-20110820/gcc-4.7-20110820.tar.bz2 and
the performance degradation rem
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50182
--- Comment #10 from Oleg Smolsky 2011-08-25
22:08:49 UTC ---
BTW, the uint16_t test also got slower for the same very reason. Here is the
inner-most loop generated by g++4.6:
text:00400DA0 loc_400DA0:
.text:00400DA0
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50182
--- Comment #9 from Oleg Smolsky 2011-08-25
16:26:05 UTC ---
AFAIK it's a production processor, a couple of years old. From x86info:
Family: 6 Model: 15 Stepping: 4 Type: 0 Brand: 0
CPU Model: Core 2 Duo E6600 Original OEM
Feature flags:
fpu vm
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50182
--- Comment #6 from Oleg Smolsky 2011-08-25
15:25:49 UTC ---
Oh, the settings and things were discussed the mail thread... Here is the
digest:
I have compiled and run a set of C++ benchmarks on a CentOS4/64 box using the
following compilers:
a)
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50182
--- Comment #5 from Oleg Smolsky 2011-08-25
15:19:57 UTC ---
Created attachment 25103
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25103
The same test preprocessed with g++ 4.1
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50182
--- Comment #1 from Oleg Smolsky 2011-08-24
22:13:26 UTC ---
Created attachment 25097
--> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25097
The test case
This is the preprocessed source for the test discussed in the mail thread.
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50182
Bug #: 50182
Summary: Performance degradation from gcc 4.1 (x86_64)
Classification: Unclassified
Product: gcc
Version: 4.6.0
Status: UNCONFIRMED
Severity: normal
Prio
