Andrew Stubbs

  • Item 1
  • Item 2

Chung-Lin Tang

Dave Gilbert

String routines

  • Wrote a hybrid ARM/Neon memcpy - it uses Neon for non-aligned cases or large (>=128k) cases

  • polished up and sent out write up of workload analysis of denbench and spec
  • Ran denbench with all memcpy and memset varients, graphed up results - SPEC 2k6 is now cooking with the memcpy set - it'll take all weekend.

64 bit atomics

  • Started looking through the Gcc code at the existing non-64bit atomic code; I need to understand how registers work in DI mode and what's going to be needed in terms of temporaries.

Ira Rosen

This week

  • bug fixes: PRs 49222, 49199, 49239, 49093
  • widening multiplication: submitted a patch to support widen-mul for unsigned types and constants in the vectorizer's pattern recognizer. Now considering to move optimize_widening_mul pass before loop optimizations and improve it to support unsigned and constants

abscense

  • Next week: holiday on Tuesday (half day) and Wednesday.

Ken Werner

This week

absence

  • I'll be out of office for the rest of the week (public holiday + vacation)

Marcin Juszkiewicz

Michael Hope

Mounir Bsaibes

Peter Maydell

Planned

Estimate

Actual

qemu-linaro-2011-06

2011-06-16

2011-06-16

Historical Milestones:

finish qemu-cont-integn

2011-01-25

2011-01-25

handed off

first qemu-linaro release

2011-02-08

2011-02-08

2011-02-08

qemu-linaro 2011-03

2011-03-08

2011-03-08

2011-03-08

qemu-linaro 2011-04

2011-04-21

2011-04-21

2011-04-21

qemu-linaro 2011-05

2011-05-19

2011-05-19

n/a

close out 1105 blueprints

2011-05-28

2011-05-28

2011-05-19

complete 1111 planning

2011-05-28

2011-05-28

2011-05-27

upstream-omap3-patches

  • started on disentangling the patchstack: submitted patches upstream for a few standalone fixes. First few steps in a big job...

omap3-usb-model

  • added QEMU's USB OHCI model to the omap3/beagle; the kernel detects the USB controller and hub but not any attached devices; more debugging required

other

  • discussions about Android emulator
  • office move
  • QEMU 0.15 is not too far in the future: need to make sure all the ARM stuff we want is in it
  • Meetings: standup, GSoC student
  • Current qemu patch status is tracked here: https://wiki.linaro.org/PeterMaydell/QemuPatchStatus

Absences

  • 1-5 August: Linaro sprint 1111
  • (maybe) 15-16 August: QEMU/KVM strand at LinuxCon NA, Vancouver [LinuxCon proper follows on 17-19th]

Ramana Radhakrishnan

Revital Eres

This week

  • Fixed an SMS patch following comments received in the gcc@ ml. While testing the fix I discovered another issue-- latest mainline ICEs with SMS flags while building libgcc on ARM configured with --with-arch=armv7-a. This new failure does not seem to be related to the above fix and I'm now investigating it.
  • Looked at code generated for spec2006's libquantum, hmmer and cactusADM_base benchmarks.

Richard Sandiford

This week

  • Spent about half of the week on auto increment/decrement. There are two execution failures left.
  • Looked at assembly comparisons between the old pass and various forms of the new pass. The results look reasonable.
  • Ran DENbench and my libav microbenchmarks to measure the difference in performance. Saw that some tests were repeatably worse.
  • Looked into those tests and realised that they were being hit by the lack of an address writeback model in the scheduler (a known limitation). Dependent stores were being scheduled in a block at the end of the loop because we said that the dependencies had 0 latency.
  • Spent most of the rest of the week on fixing that limitation. One of the difficulties is that define_bypass currently requires a complete list of instruction reservations. This is difficult for things like writeback because the result could in principle be used by many different instructions. Decided to generalise define_bypass so that it can handle filename-style globs.
  • Wrote a patch to model writeback in NEON.
  • Wrote a patch to model writeback in core instructions. However, while doing this, I noticed that the behaviour I'm seeing on out Cortex-A8 doesn't match what I'd expected from GCC's A8 scheduler description (or the documentation). Talked with Ramana about it. Distilled a benchmark.
  • These scheduler changes didn't improve the DENbench and libav scores much by themselves, but the combination of the scheduler and auto inc/dec changes did produce noticeable improvements in some libav benchmarks and rather smaller improvements in some DENbench ones.

Next week

  • Finish scheduler work, in light of observed behaviour.
  • More testing prior to submission.

Abscense

  • I'm away the week of 13th June.

Ulrich Weigand

WorkingGroups/ToolChain/ActivityReports/2011-06-03 (last modified 2011-06-08 19:45:26)