Andrew Stubbs

  • Worked on the ARM 16 -> 64-bit multiply-and-accumulate problem. Bernd kindly provided a prototype patch to help. I've tried to understand what needs to be done, but I didn't have enough time to get to the bottom of it. So far, I think I know why the existing code doesn't work, and I think I have a way forward. It does appear that the real problem ought to be solved in the tree optimizers, though.

  • Committed the FSF GCC 4.5.3 merge to the Linaro 4.5 branch. Testing did not show any trouble.
  • Matthias requested an additional 4.5 merge to pick up a new bug fix, so I've done the merge, and submitted the merge request for testing.
  • Committed Maxim's compound conditionals optimization patch - a merge from Linaro GCC 4.5.
  • There was some confusion caused by the lp:gcc-linaro/4.6 branch history accidentally getting re-written. After some discussion on #bzr I managed to figure out what happened, posted a warning to linaro-toolchain mailing list, and changed the branch configuration to prevent it happening again.
  • Committed Mark Shinwell's BRANCH_COST patch to Linaro GCC 4.6 - another merge from GCC 4.5.
  • Merged from FSF GCC 4.6 to Linaro 4.6 and submitted the patch for testing.
  • Richard Earnshaw approved my recent Thumb2 constants patch, but only if I modify it slightly. I've begun work on the changes, but I still need to test them. I won't be able to commit them until the ADDW/SUBW patch has been approved.
  • Ramana has reviewed my EABI half-precision function names patch, and discovered that the return types are wrong. I have no idea how this happened - the changes are deliberate so they must have been based on something, but I no longer have the same documents I had when I did the work, and it clearly doesn't match my current ones. In any case, the changes make no practical difference as function return values are always as wide a register anyway.

Chung-Lin Tang

Last week

  • Launchpad #748138: "ICE in redirect_jump, at jump.c:1443". Related to shrink-wrap, discussed a bit with Bernd off-list. Sent fix today (Mon.) to gnu-internal; will need to merge to Linaro.
  • CoreMark combine canonicalize compares patch set: bootstrapped and tested with clean results on powerpc, added comments and updated upstream submission. Machine independent parts okayed by Jeff Law, now committed upstream. ARM parts still pending review.

  • Compiled back-list of upstream patches, and sent to patches@linaro.org

  • Traveled to Budapest, Hungary for Linaro Developer Summit on Saturday.

This week

  • Linaro Developer Summit at Budapest all week.

Dave Gilbert

Bug fighting

  • Tracked bug 774175 (apt segfault on armel on oneiric) down to the

cortex-a8 branch erratum bug that we found as part of the bug jam a few weeks ago (affecting the more obscure vtk package) - Richard's existing binutils fix should fix this.

String routines

  • Struggled to get 'perf' to get sane results from profiling spec; some of the samples are obviously being associated with the wrong process somewhere along the process (e.g. it's showing significant samples in the sh process but in a library that's used by the actual benchmark.
  • latrace on spec still running on ursa2
  • Wrote a non-neon memcpy; as expected it's aligned performance is very similar to libc/kernel - it's a bit faster in some places but slower in some odd places (e.g. n*32+1 bytes is a lot slower for some

reason). It's also really bad on mis-aligned cases, I tried to take advantage of the v7's ability to do misaligned loads - but they really are quite slow.

Ira Rosen

  • backported vzip fix to GCC 4.5 and 4.6 (PR 48252)
  • merged auto-detection of vector size patch to gcc-linaro 4.6
  • started looking into vectorization of ffmpeg

Ken Werner

  • finished libunwind support of detection and handling of signal frames on ARM Linux. RT and non-RT signal frames are handled for both >=2.6.18 and <2.6.18 kernels. The *test-resume-sig testcases are passing now.

  • briefly looked into what needs to be done in order to add 64bit sync_* ops

  • prepared for LDS

Marcin Juszkiewicz

Michael Hope

Mounir Bsaibes

Peter Maydell

merge-correctness-fixes

  • some minor patches committed: SPARC build issues, Neon UNDEFs, restore base reg properly for Thumb LDMs that abort midway
  • v2 of configure patch to print list of valid targets
  • some work on fixing QEMU FPSCR status flags (last remaining item in this blueprint); submitted a patchset fixing everything except the various VCVT instructions (which have trickier softfloat bugs)
  • submitted patch fixing NaN behaviour in VMLA/VMLS/VNMLA/VNMLS

other

  • the Google Summer of Code QEMU project to work on upstreaming some of the Android emulator has been approved; I will be mentoring Patrick Jackson, who is the student who will be doing this work
  • qemu-linaro 2011-05 is unlikely to have any code changes since 2011-04; we might release it anyway just because it's the final one of the cycle Current qemu patch status is tracked here: https://wiki.linaro.org/PeterMaydell/QemuPatchStatus

Absences

  • 13-19 May: UDS, Budapest
  • (maybe but unlikely) 15-16 August: QEMU/KVM strand at LinuxCon NA,

  • Vancouver [LinuxCon proper follows on 17-19th]

Ramana Radhakrishnan

Revital Eres

Richard Sandiford

This week

  • Committed interleaved load/store vectorisation changes upstream.
  • Merged the vldN and vstN intrinsic improvements into Linaro 4.5 and 4.6. (Thanks for the quick reviews here.)
  • Backported the interleaved load/store vectorisation changes to Linaro 4.5 and 4.6. This took a while because the patch series touches turbulent code. Submitted merge requests.
  • Merged Sergey Grechanik's NEON reload improvement into Linaro 4.5 and 4.6.
  • Got ready for summit.

Ulrich Weigand

GDB

  • Committed support for NEON registers in core dumps (bug #615972) to Linaro GDB (not yet in mainline).
  • Investigated root cause of bug #615996 (gdb.cp/templates.exp) and started exploring ways to fix it.

GCC

  • Committed fix for bug #759409 (Profiled bootstrap fails in GCC 4.5) to FSF GCC 4.5 branch and Linaro GCC 4.5.

WorkingGroups/ToolChain/ActivityReports/2011-05-06 (last modified 2011-05-16 18:51:41)