* Linaro GCC
Continued work on 64-bit shift / extend / etc. in NEON. I have posted an
RFC to the gcc-patches list in the hope of getting some feedback on how
best to fix this. No response yet. Hopefully some of the Linaro guys are
at least looking at it ...
Merged FSF GCC 4.5 and 4.6 into the Linaro GCC release branches prior to
the release next week.
Set more benchmarking work running in my ongoing investigation into
generic tuning.
Did a dry run of the extra release testing Michael normally does. It
failed. Michael says he's fixed it now, but I know how to do my bit, so
fingers crossed.
* Other
Experienced some IT/connectivity outages within Mentor. Resolved now.
==Progress===
* Off sick on Monday
* Systematic testing duty - few Aarch64 issues.
* Linaro patch review duty.
* Tested my vcvt fixed point patch and close to committing.
* Worked on sometime on movw / movt for symbol references rather than
constant pools . While this gives nice benefits it's a code size hog
and needs further investigation.
* PGO patch being tested finally and should go back up for review.
=== Plans ===
* Release week next week.
* Start looking at partial_partial PRE.
* Finish committing by backlog of patches.
Absences.
* Dec 19 - 31st Dec - Tentatively booked
* Feb 6-10 : Linaro Connect Q1.12/
Summary:
* Patch linaro crosstool-ng.
* Windows install package
Details:
* Patch linaro crosstool-ng:
* Back port upstream patches.
* Check-in the zlib/libiconv/expat/ncurses related patches to linaro branch.
* Create reference windows install package for linaro toolchain from
installjammer. The install process works well on Win7.
Plans:
* Investigate test on Windows.
Best regards!
-Zhenqiang
Hi,
OpenEmbedded:
* started on creating a receipts to compile the "core-image-minimal"
using an external prebuilt toolchain (csl arm-2011.03)
* there are still a lot of warnings at the do_package/do_package_qa task
* the good news is that the build process finishes and kernel plus root
file system image gets created
* the bad news is that the rootfs lacks some important libs like libc
and therefore won't run under qemu-system-arm
(since init, busybox, etc. are dynamically linked)
* currently a 3-lines hack on oe-core is required to be able to
overwrite a task of the generic glibc receipt; all other files could go
into a separate layer
Linaro Android:
* had a quick look into the EABI attribute tag issue
Regards
Ken
== String routines ==
* Sent updated memchr to the eglibc list
== 64 bit atomics ==
* Ran a set of timing consistency tests that a colleague had sent me
while I was off; Panda passed those, so time
doesn't appear to be going backwards or anything, so that's not the
problem with membase.
* Pushed the code into linaro-gcc.
== QEmu ==
* Tested Peter's prerelease - all good.
* Started looking at the issues for running in TCG mode on ARM
== Other ==
* Read through the ARMv8 instructions docs that landed on arm.com;
quite interesting. Note that multiple instruction
IT blocks are listed as being deprecated for 32bit mode on v8
(although this will work but it can be put in a mode to fault
you to make it easy to find the uses).
* Some debugging of Panda odd timing issue with Paul Mckenney.
Dave
RAG:
Red:
Amber:
Green:
Current Milestones:
|| || Planned || Estimate || Actual ||
||upstream-omap3-cleanup || 2011-11-10 || 2011-12-15 || ||
||cp15-rework || 2012-01-06 || 2012-01-06 || ||
||initial-a15-system-model || 2012-01-27 || 2012-01-27 || ||
||qemu-kvm-getting-started || 2012-03-04?|| 2012-03-04?|| ||
(for blueprint definitions: https://wiki.linaro.org/PeterMaydell/QemuKVM)
Historical Milestones:
||add-omap3-networking || 2011-10-13 || 2011-10-13 || 2011-10-13 ||
||a15-systemmode-planning || 2011-10-13 || 2011-10-13 || 2011-09-22 ||
||a15-usermode-support || 2011-11-10 || 2011-11-10 || 2011-10-27 ||
== qemu-kvm-getting-started ==
* now reasonably set up to run KVM under Fast Model; howto is here:
https://wiki.linaro.org/PeterMaydell/A15OnFastModels
* rebased kvm patches into qemu-linaro
* fixed bug where we weren't passing cpu number to kvm properly
when delivering an interrupt
* sent some minor patches to upstream qemu that will be needed for
kvm (eg configure script tweaks)
== initial-a15-system-model ==
* started on cleaning up a9/11mpcore private peripheral implementation;
now mostly done and looking much better as a base for a15
== other ==
* preparation for qemu-linaro release (rolled tarball, tested)
* submitted patch to fix buffer overrun in GIC model
* discussion: linux-user mode race conditions, and in particular
how we should handle signals that arrive during syscall emulation
* upstream patch review: imx31 round 3
-- PMM
== GDB ==
* Completed new set of patches to support both "info proc" and
core file generation across the remote protocol, and posted
them to the mailing list for review.
* Tested GDB trunk in preparation for 7.4 release branch point
on multiple platforms; analyzed and fixed a couple of problems,
some also present on ARM in remote testing. Patches checked
in to mainline.
Mit freundlichen Gruessen / Best Regards
Ulrich Weigand
--
Dr. Ulrich Weigand | Phone: +49-7031/16-3727
STSM, GNU compiler and toolchain for Linux on System z and Cell/B.E.
IBM Deutschland Research & Development GmbH
Vorsitzender des Aufsichtsrats: Martin Jetter | Geschäftsführung: Dirk
Wittkopp
Sitz der Gesellschaft: Böblingen | Registergericht: Amtsgericht
Stuttgart, HRB 243294
== This week ==
* More on -fsched-pressure. Testing on POWER7 showed a degenerate case
that I'd failed to handle well. Fixed that. Saw that part of the
problem on POWER7 was that IRA was using a combination of GENERAL_REGS
and CR_REGS as a single pressure class, so there appeared to be 39
registers available for storing integers. Fixed (or worked around) that.
Tweaked a few other things too. The only denbench result that I
wasn't happy with was RSA, where both forms of -fsched-pressure are
significantly worse than -fno-sched-pressure. Tracked down the cause
of that. We had a block BB1:
A: (set (reg:DI X) Y)
B: (clobber (reg:DI Z))
C: (set (subreg:SI (reg:DI Z) 0) (... X ...))
D: (set (subreg:SI (reg:DI Z) 4) (...))
where B makes sure that Z is treated as dead before C. Interblock
motion causes B to be scheduled in an earlier block, but none of
the other instructions can be. This means that, when we schedule BB1,
it still contains A, C and D, and Z now appears to be live on entry to
the block. C therefore appears to reduce register pressure, because
it contains the last use of X, and appears to leave Z's liveness
unaffected. In reality it should be treated as increasing register
pressure by 1 (-1 for the death of X, +2 for the birth of Z).
I "fixed" this by moving C's dependencies to B, a bit like we do
for scheduling groups (although none of the other handling of
scheduling groups should apply). This made a big difference,
so that the new code is a win on RSA.
There's still one SPEC2006 degradation on POWER7 that I want
to look at.
* Caught up on a lot of mail. gcc-patches backlog has gone down
from ~4900 when I got back to ~500.
* Briefly looked at x86's drap support, to see what would be needed
for ARM. Didn't look for long though: the overhead seems excessive
for optional alignment, and the agreement seemed to be that 128-bit
alignment wouldn't really make much of a difference anyway.
Richard
Hi!
* Continued with running eembc, coremark, denbench and spec2k on the ursas
with the latest of the Linaro and FSF series. The variants used were
o3-neon and o3-neon-novect. Something went wrong with the variants the
first time, so I had to rerun the tests once.
Discussed draft report with Michael, next week I will share with the rest
of the team.
* Did a rerun SPEC2K runs with "train" and "ref" data sets. I did -o2 and
-o3 runs on a panda with the two data sets. Asked for a sanity check of the
numbers.
* Prepared and held a presentation about the tcwg internally.
* Will be tied up with internal work for the most of w49.
Best regards
Åsa
Hi,
- Ran eon with gcc 4.7: there are much more loops similar to the one
in lp#831094 that get vectorized (due to some data ref analysis
improvement), so the impact of disabling peeling for such loops (i.e.
loops with low loop bound) is even bigger than for 4.6, and
vectorization improves the performance by 2.5%.
I prefer to understand the peeling/alignment situation better and not
just commit this patch (and I spent some time trying to do that).
- Fixed PR 51301 - a bug in over-promotion pattern. Proposed for merge
to gcc-linaro-4.6.
- Merged the last SLP patch to gcc-linaro-4.6.
Ira
