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[Bug tree-optimization/30052] [4.2/4.3 Regression] points-to analysis slow and memory hungry
- From: "belyshev at depni dot sinp dot msu dot ru" <gcc-bugzilla at gcc dot gnu dot org>
- To: gcc-bugs at gcc dot gnu dot org
- Date: 11 Sep 2007 19:51:00 -0000
- Subject: [Bug tree-optimization/30052] [4.2/4.3 Regression] points-to analysis slow and memory hungry
- References: <bug-30052-7667@http.gcc.gnu.org/bugzilla/>
- Reply-to: gcc-bugzilla at gcc dot gnu dot org
------- Comment #46 from belyshev at depni dot sinp dot msu dot ru 2007-09-11 19:50 -------
(In reply to comment #45)
> Uh, it's not slow anymore since I committed the patch last month.
Please define "not slow" :)
I stopped compilation of "sipQtGuipart0.cpp" after 2.5+ hours and called
timevar_print (stdout) from gdb:
tree PTA : 7383.90 ( 0%) wall 652668 kB ( 0%) ggc
tree alias analysis : 550.29 ( 0%) wall 1192023 kB ( 0%) ggc
tree operand scan : 178.91 ( 0%) wall 77836 kB ( 0%) ggc
(all other timevars < 10 s)
This is gcc-4.2 r128355. It takes about the same amount of memory (~500 MB) as
4.1 but never finishes.
Unlike 4.2, 4.3 r128377 runs out of memory, and it is much slower than 4.1.
Here is output from timevar_print() from gdb at the time it hit the swap (about
four minutes):
tree find ref. vars : 15.88 ( 0%) wall 990776 kB ( 0%) ggc
tree PTA : 2.22 ( 0%) wall 23052 kB ( 0%) ggc
tree alias analysis : 13.24 ( 0%) wall 8179 kB ( 0%) ggc
tree call clobbering : 52.63 ( 0%) wall 2020 kB ( 0%) ggc
tree flow sensitive alias: 1.28 ( 0%) wall 123311 kB ( 0%) ggc
tree flow insensitive alias: 21.84 ( 0%) wall 0 kB ( 0%) ggc
tree memory partitioning: 61.98 ( 0%) wall 870 kB ( 0%) ggc
...
tree operand scan : 21.86( 0%) wall 128117 kB ( 0%) ggc
For comparison, 4.1 compiles that file in 50 seconds and takes roughly 500 MB.
(note all timings were done with --enable-checking=release compilers).
--
belyshev at depni dot sinp dot msu dot ru changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |belyshev at depni dot sinp
| |dot msu dot ru
Keywords| |memory-hog
Last reconfirmed|2007-03-14 14:21:37 |2007-09-11 19:51:00
date| |
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30052