[Bug rtl-optimization/50101] GCC 4.5 and 4.6 generate suboptimal code on ppc for countdown loops when the CTR register cannot be used

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50101 --- Comment #9 from Jeffrey A. Law 2011-08-19 15:35:36 UTC --- -BEGIN PGP SIGNED MESSAGE- Hash: SHA1 On 08/19/11 08:05, meissner at linux dot vnet.ibm.com wrote: > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50101 > > --- Comment #8 fro

[Bug rtl-optimization/50101] GCC 4.5 and 4.6 generate suboptimal code on ppc for countdown loops when the CTR register cannot be used

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50101 --- Comment #8 from Michael Meissner 2011-08-19 14:05:51 UTC --- On Thu, Aug 18, 2011 at 08:58:28AM +, rguenth at gcc dot gnu.org wrote: > Did you try pessimizing the non-ctr reg alternatives (and the memory > alternative even more)? Like ad

[Bug rtl-optimization/50101] GCC 4.5 and 4.6 generate suboptimal code on ppc for countdown loops when the CTR register cannot be used

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50101 --- Comment #7 from Richard Guenther 2011-08-18 08:58:28 UTC --- (In reply to comment #3) > (In reply to comment #2) > > I suppose the CTR is introduced after RA in machine-dependent reorg? In > > which > > case can the issue be fixed on branch

[Bug rtl-optimization/50101] GCC 4.5 and 4.6 generate suboptimal code on ppc for countdown loops when the CTR register cannot be used

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50101 --- Comment #5 from Michael Meissner 2011-08-17 15:45:08 UTC --- Created attachment 25035 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25035 IRA rtl dump file

[Bug rtl-optimization/50101] GCC 4.5 and 4.6 generate suboptimal code on ppc for countdown loops when the CTR register cannot be used

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50101 --- Comment #4 from Michael Meissner 2011-08-17 15:44:20 UTC --- Created attachment 25034 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25034 Sched1 rtl dump file

[Bug rtl-optimization/50101] GCC 4.5 and 4.6 generate suboptimal code on ppc for countdown loops when the CTR register cannot be used

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50101 --- Comment #6 from Michael Meissner 2011-08-17 15:45:59 UTC --- Created attachment 25036 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25036 Postreload rtl dump file

[Bug rtl-optimization/50101] GCC 4.5 and 4.6 generate suboptimal code on ppc for countdown loops when the CTR register cannot be used

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50101 --- Comment #3 from Michael Meissner 2011-08-17 15:43:00 UTC --- (In reply to comment #2) > I suppose the CTR is introduced after RA in machine-dependent reorg? In which > case can the issue be fixed on branches by adjusting register cost of the

[Bug rtl-optimization/50101] GCC 4.5 and 4.6 generate suboptimal code on ppc for countdown loops when the CTR register cannot be used

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50101 --- Comment #2 from Richard Guenther 2011-08-17 08:10:03 UTC --- I suppose the CTR is introduced after RA in machine-dependent reorg? In which case can the issue be fixed on branches by adjusting register cost of the CTR?

[Bug rtl-optimization/50101] GCC 4.5 and 4.6 generate suboptimal code on ppc for countdown loops when the CTR register cannot be used

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=50101 --- Comment #1 from Michael Meissner 2011-08-16 20:57:01 UTC --- Created attachment 25026 --> http://gcc.gnu.org/bugzilla/attachment.cgi?id=25026 Example test case