ON THE CALL: Shin-ming Liu (HP), Vladimir Makarov (Red Hat), Diego
Novillo (Red Hat), Mark Smith (Gelato), Bob Kidd (UIUC), Andrey
Belevantsev (RAS), Arutyun Avetisyan (RAS), Mark Davis (Intel)
We spent some time up front discussing the GCC track at the upcoming
Gelato ICE conference (www.gelato.org/meeting). Confirmed
topics/speakers include:
* LLVM - Chris Lattner
* LTO - Mark Mitchell
* Aliasing update - Dan Berlin
* Parallel programming with GCC - Diego Novillo
* ORC back end for GCC - Shin-Ming Liu
* Superblock work - Bob Kidd
* Russian Academy of Science scheduler improvement update - Andrey
Belevantsev and Arutyun Avetisyan
* Intel micro-architecture talk - Cameron McNairy
* Spec2006 - Gerolf Hoflehner (provided Spec2006 has
been release at conference time)
* GCC IP issues - Dan Berlin
Updates from call participants can be found below.
NEXT MEETING: March 16th, 2006. Details will be emailed out prior to
the call.
Andrey Belevantsev:
-------------------
We've fixed the alias propagation patch according to Dan Berlin's
suggestions and sent it to the list. Namely, bitmaps are now used
instead of varrays for storing points-to information; global flags are
moved to 'struct function' to be function local and avoid interference
with PA passes; coding style issues are fixed. Now we are looking for
further feedback from Dan and Diego.
Vladimir Makarov has approved one patch from the set of speculation
patches. Vlad has asked us to wait with committing until he'll review
all the rest. That's better because the separate patches don't allow
to use speculation. We've also slightly improved the probability patch
originally submitted by Peter Steinmetz and committed it (the thread
is at http://gcc.gnu.org/ml/gcc-patches/2006-01/msg02223.html).
We've implemented code motion routines of the new scheduler we're
working on. The routines perform DAG traversal in search of the
original forms of the operation being scheduled. When original
operation is found, it is either deleted or changed into a simple copy
operation. If the operation should be moved through a join point, a
bookkeeping copy should be added on all other paths. This logic is
implemented in a slightly different way depending on the type of the
operation we are moving (sequential or conditional branch). Now we
have focused on adapting the scheduling loop routines and the logic of
choosing the best instruction from the set of available ones from the
Haifa scheduler. The code motion part will be fully tested only after
implementation of these "scheduler frontend" routines.
Bob Kidd:
---------
There's not much new on the superblock work. I will check the
superblock patch into the ia64-improvements tree later today. After
mainline is merged into the tree, I'll run some performance numbers.
Vladimir Makarov:
-----------------
I was brief on the last teleconference.
I told that it is good to have some info about SPEC2006 and comparison
of Itanium gcc and icc on this benchmark. Some discussion about
MMU->address bypass for Montecito.
Diego Novillo:
--------------
Mostly working on getting the OpenMP implementation in mainline. So
far the C and Fortran front end changes have been incorporated. The
C++ changes are being reviewed. It will be released with GCC 4.2.
I have also been working on changes to the aliasing infrastructure to
avoid some of the penalties we pay for representing alias relations
directly in the IL.
Other than that, it's been the usual maintenance work.
