[Bug tree-optimization/68128] A huge regression in Parboil v2.5 OpenMP CUTCP test (2.5 times lower performance)

[jakub at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68128

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |ASSIGNED
   Last reconfirmed|                            |2015-11-25
           Assignee|unassigned at gcc dot gnu.org      |jakub at gcc dot gnu.org
     Ever confirmed|0                           |1

--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Created attachment 36838
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=36838&action=edit
gcc6-pr68128.patch

Untested optimization to turn shared clauses of scalar vars into firstprivate
if quickly determined not to be written into in the body (during gimplification
plus tree-nested follow-up).