> On Wed, Dec 11, 2013 at 1:21 AM, Martin Liška <marxin.li...@gmail.com> wrote: > > Hello, > > I prepared a collection of systemtap graphs for GIMP. > > > > 1) just my profile-based function reordering: 550 pages > > 2) just -freorder-blocks-and-partitions: 646 pages > > 3) just -fno-reorder-blocks-and-partitions: 638 pages > > > > Please see attached data. > > Thanks for the data. A few observations/questions: > > With both 1) (your (time-based?) reordering) and 2) > (-freorder-blocks-and-partitions) there are a fair amount of accesses > out of the cold section. I'm not seeing so many accesses out of the > cold section in the apps I am looking at with splitting enabled. In
I see you already comitted the patch, so perhaps Martin's measurement assume the pass is off by default? I rebuilded GCC with profiledboostrap and with the linkerscript unmapping text.unlikely. I get ICE in: (gdb) bt #0 diagnostic_set_caret_max_width(diagnostic_context*, int) () at ../../gcc/diagnostic.c:108 #1 0x0000000000f68457 in diagnostic_initialize (context=0x18ae000 <global_diagnostic_context>, n_opts=n_opts@entry=1290) at ../../gcc/diagnostic.c:135 #2 0x000000000100050e in general_init (argv0=<optimized out>) at ../../gcc/toplev.c:1110 #3 toplev_main(int, char**) () at ../../gcc/toplev.c:1922 #4 0x00007ffff774cbe5 in __libc_start_main () from /lib64/libc.so.6 #5 0x0000000000f7898d in _start () at ../sysdeps/x86_64/start.S:122 That is relatively early in startup process. The function seems inlined and it fails only on second invocation, did not have time to investigate further, yet while without -fprofile-use it starts... On our periodic testers I see off-noise improvement in crafty 2200->2300 and regression on Vortex, 2900->2800, plus code size increase. Honza
