== GDB ==
* Worked on support for cross-platform core file generation.
Posted initial set of patches for comments.
* Created "Toolchain support for kernel debugging" blueprint.
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
Hi,
I made some progress on transforming the hacks I did to get libunwind
working on Android into proper patches that can go upstream. Things learned:
* bionic employs OpenBSD header files that therefore lack some GNU and
ARM specific defines (only small fix needed - plan is to change
libunwind to work with non-patched bionic too)
* Android basically provides all the functionality that is required
for libunwind-ptrace - but...
* no one seems to build libunwind with remote unwind functionality
(including libunwind-ptrace) only
* most of the issues can be avoided by changing libunwind to be more
portable
Regards
Ken
* Still having trouble with using multistrap/pdebuild-cross for
cross-compiling Firefox - it looks like only x86 packages get downloaded,
not armel. I have asked Wookey for advice, and he will try to reproduce the
build.
* Falling back to native compiling until the cross-compiling set up has been
sorted out. I will now take a look at how to pass different compiler options
to the Mozilla build system and how to build different parts of the program.
Best Regards
Åsa
(short week: 4 days)
RAG:
Red:
Amber:
Green: blog started :-) http://translatedcode.wordpress.com/
Current Milestones:
|| || Planned || Estimate || Actual ||
||a15-usermode-support || 2011-11-10 || 2011-11-10 || ||
||upstream-omap3-cleanup || 2011-11-10 || 2011-11-10 || ||
Historical Milestones:
||qemu-linaro-2011-07 || 2011-07-21 || 2011-07-21 || 2011-07-21 ||
||qemu-linaro 2011-08 || 2011-08-18 || 2011-08-18 || 2011-08-18 ||
||qemu-linaro 2011-09 || 2011-09-15 || 2011-09-15 || 2011-09-15 ||
||add-omap3-networking || 2011-10-13 || 2011-10-13 || 2011-10-13 ||
||a15-systemmode-planning || 2011-10-13 || 2011-10-13 || 2011-09-22 ||
== other ==
* upstream patch review, putting together pull requests
* more time spent on qemu on ARM host apparent memory corruption
bug (no luck yet :-(); found a Valgrind bug in the process,
though (KDE:284472). This ate up way too much of this week.
* A15 KVM planning work
* meetings etc
* moved over to patches.linaro for QEMU patch tracking
-- PMM
Hi,
* widening shifts - finally committed upstream
* SLP loads with different offsets and operand swaps - committed upstream
* SLP with multiple types - merged to gcc-linaro-4.6
* vectorizer stuff: patch review, test fixes, discussions, bug fix
* Ramana and I discussed what can be done with VEC_PERM_EXPR for NEON,
and created https://blueprints.launchpad.net/gcc-linaro/+spec/support-vec-perm
for this issue.
Ira
Following on from last night's performance call, I had a look at how
64 bit integer operations are mapped to NEON instructions. The
summary is:
* add - fine
* subtract - fine
* bitwise and - fine
* bitwise or - fine
* bitwise xor - fine
* multiply - can't as the instruction tops out at 32 bits. Might be
able to compose using VMLAL
* div, mod - no instruction
* negate - instruction tops out at 32 bits, but could be turned into
vmov #0, vsub
* left shift constant - missing
* right shift constant - missing
* right arithmetic shift constant - missing
* left shift register - missing
* right shift register - tricky, as you do this as a left shift -register
* not - no instruction, but could be done through a vceq, #0?
* bitwise not - missing
I also noticed that the replicated constants aren't being used. A
pre-increment is load constant pool; vadd but could be done as a vmov,
#-1; vsub. The same with pre-decrement - it could be done as a vmov,
#-1; vadd.
This seems worth blueprinting.
-- Michael
limits-fndefn.c takes an impressively long time to run. On an idle
machine, -O3 -g -c takes 17:31 and -O2 -g -c takes The test already
has a dg-timeout-factor of 4 giving a total timeout of 20 minutes.
Removing the -g brings this down to 30 s. Keeping the -g and adding
-fno-var-tracking brings this down to 45 s.
We could bump the multiplier up to 8 but it's getting a bit
ridiculous. Any thoughts?
-- Michael
== Last week and today ==
* Backported fix for returning std::pair<bool, bool>. Unfortunately
this showed up a regression on 4.5. I couldn't reproduce it cross,
and the testcase itself looks innocuous, so I'm wondering whether
the patch might trigger a miscompilation of cc1plus.
* Committed SMS register-scheduling patches upstream and backported
to Linaro 4.6.
* Most of the week spent on -fsched-pressure. Still trying a few
variations in order to get the right balance. (My local haifa-sched.c
now has about 20 new toggles.) Still feel like I'm making progress,
rather than hitting the point of diminishing returns.
Hope Connect goes well. See everyone in a few weeks' time.
Richard
Completed the 4.5 and 4.6 FSF to Linaro merges.
Spun the Linaro GCC release tarballs, uploaded them to the test farm,
and set off the test builds.
Continued looking at the constant reuse optimization. This time I've
build GCC itself with the new pass to see how many optimization
opportunities there are. This shook out a lot more small bugs, which was
useful.
Backported my negative-shifts patch to Linaro 4.6, pushed it to
Launchpad for testing, and then committed it to 4.6 once in was approved.
Experimented with running SPEC2K on A8 and A9 boards in order to
establish a baseline for the generic tuning tweaks. A short test doesn't
give much clue as to what can be achieved, and a long test takes way too
long. The problem is also complicated by the benchmarks where the A8
tuning works better on A9 than A9 tuning does. :S
Received a bug report (GCC bugzilla 50717) for my widening multiplies
patches. Analysed the problem, developed a patch, and posted it to
gcc-patches.
