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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org> To: gcc-bugs@gcc.gnu.org Subject: [Bug middle-end/52066] New: IRA and reginfo initialization too expensive Date: Tue, 31 Jan 2012 13:21:00 -0000 [thread overview] Message-ID: <bug-52066-4@http.gcc.gnu.org/bugzilla/> (raw) http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52066 Bug #: 52066 Summary: IRA and reginfo initialization too expensive Classification: Unclassified Product: gcc Version: 4.7.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: middle-end AssignedTo: unassigned@gcc.gnu.org ReportedBy: jakub@gcc.gnu.org On compilation of an empty file, we spend almost half of the runtime on IRA and reginfo cost initialization. Inlining reg_class_subset_p and reg_classes_intersect_p gives us at least tiny part of compile time back, at the cost of some small code growth. For --enable-checking=release x86_64-linux cc1: ~/timing --drop 20 -c 2500 ./cc1.vanilla empty.c -quiet Strip out best and worst 500 realtime results minimum: 0.006243475 sec real / 0.000018634 sec CPU maximum: 0.032220578 sec real / 0.000203440 sec CPU average: 0.006542800 sec real / 0.000036352 sec CPU stdev : 0.000050402 sec real / 0.000004406 sec CPU ~/timing --drop 20 -c 2500 ./cc1 empty.c -quiet Strip out best and worst 500 realtime results minimum: 0.006115241 sec real / 0.000017569 sec CPU maximum: 0.033226603 sec real / 0.000197238 sec CPU average: 0.006384943 sec real / 0.000036349 sec CPU stdev : 0.000049180 sec real / 0.000004284 sec CPU readelf -WS cc1{.vanilla,} | grep '\text' [12] .text PROGBITS 00000000004b21a0 0b21a0 78e7b4 00 AX 0 0 16 [12] .text PROGBITS 00000000004b21a0 0b21a0 78ed34 00 AX 0 0 16
next reply other threads:[~2012-01-31 13:02 UTC|newest] Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top 2012-01-31 13:21 jakub at gcc dot gnu.org [this message] 2012-01-31 13:25 ` [Bug middle-end/52066] " jakub at gcc dot gnu.org 2012-01-31 13:57 ` rguenth at gcc dot gnu.org 2012-01-31 15:48 ` jakub at gcc dot gnu.org 2012-10-09 20:46 ` steven at gcc dot gnu.org
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