[Bug rtl-optimization/38518] Excessive compile time with -O3

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=38518

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |ra
             Status|ASSIGNED                    |NEW
                 CC|                            |vmakarov at gcc dot gnu.org
           Assignee|rguenth at gcc dot gnu.org         |unassigned at gcc dot gnu.org

--- Comment #11 from Richard Biener <rguenth at gcc dot gnu.org> ---
With 4.9.0

-O1: 5s
-O2: 7s
-O3: 41s

the profile at -O3 is mostly flat, worst offender is LRA hard-reg assignment
which may also contribute to the high DF time.

Execution times (seconds)
 phase opt and generate  :  41.00 (100%) usr   0.68 (94%) sys  41.75 (100%)
wall  451991 kB (99%) ggc
 df reaching defs        :   5.87 (14%) usr   0.03 ( 4%) sys   5.82 (14%) wall 
     0 kB ( 0%) ggc
 dominance frontiers     :   2.52 ( 6%) usr   0.00 ( 0%) sys   2.51 ( 6%) wall 
     0 kB ( 0%) ggc
 LRA hard reg assignment :   4.94 (12%) usr   0.04 ( 6%) sys   4.96 (12%) wall 
     0 kB ( 0%) ggc
 TOTAL                 :  41.05             0.72            41.84            
456534 kB

It's now a RA issue, I'm out of here (though I'd even consider closing this
as fixed - I've added the testcase to daily monitoring).