All,
During Connect the suggestion was made that each working group should have
its own IRC Channel for discussions and topics relating to the group in
particular (as opposed to #linaro which is 'generic' Linaro conversations).
Therefore I have just set up #linaro-tcwg on Freenode for the Toolchain
Working Group.
This channel is public and open to anyone who wants to talk with the TCWG
group about anything toolchain related.
Thanks,
Matt
--
Matthew Gretton-Dann
Toolchain Working Group, Linaro
== This Week ==
* malloc propagation (4/10)
- Resolved bootstrap comparison failure
- Patch passes validation with and without LTO.
- Working on handling indirect calls.
* type promotion (3/10)
- Created patche for resolving ICE with armv3/armv5t.
- Have got a hack-ish patch to address interference between type promotion and
widening_mul/bswap optimizations, but needs improvement.
* Misc (3/10)
- Meetings
- Visa interview
== Next Week ==
- Continue with malloc propagation, type promotion
# Progress #
* TCWG-1159,New design of GDB/GDBserver target description. [3/10]
Looks people who can review my patches is on holiday, so I committed
7 patches and leave the rest 19 patches there. Need to think about
how to make people more confident on these patches.
* PR 21717, PR 21555, fixed. Pushed to master and 8.0 branch.
[1/10]
* TCWG-1162, Test GDB+OpenOCD with AArch64 boards. [3/10]
I can run gdb regression tests with OpenOCD on HiKey. After I power
cycle the board, the first several tests can run, but the following
tests failed because the board goes to an odd state. Something wrong
in OpenOCD side.
Try GDB aarch64 bare-metal debugging with QEMU, and then find a bug
in newlib which doesn't initialize FPU, so some FPU instruction will
trigger und exception.
* TCWG-561, Handle unavailable memory during frame unwinding. [2/10]
Lear C++ move assignment and move constructor. Finish the code, and
testing the patches.
* Send my GDB target description talk abstract to Linaro SFO17.
* Misc [1/10]
# Plan #
* Mon and Tue off.
* TCWG-561, TCWG-1159.
--
Yao Qi
4 day week.
[TCWG-614] Range Extension Thunks
- Rebased due to upstream refactoring
- Pinged but no upstream review progress
[Compiler-rt]
Clang no longer always uses base PCS for all the builtins it expands
such as the _Complex helpers.
- Added tests to make sure RTABI 4.1.2 Floating Point helpers all use
softfp in Clang D35538 and llvm D35904.
- Reviewer pointed out useful script update_llc_test_checks.py that
can simplify writing of llc tests. Well worth checking out
[LLD]
Looks like lld use in Android may be becoming more likely, major
blocking feature is lack of Cortex-A53 erratum fix 843419.
- I've commented on the upstream PR https://bugs.llvm.org/show_bug.cgi?id=33463
- I've written some test cases and have started a prototype implementation
Submitted Linaro Connect presentation proposal for Functional Safety
and Development tools.
Plans:
In priority order:
- range extension thunks
- Cortex-A53 843419
- Compiler-rt
== Progress ==
* TCWG-1205 - Minor tweaks to Jenkins LLVM jobs [1/10]
- Sent a few patches to make the Jenkins jobs more friendly and/or
fix them for new changes in the upstream release script
* TCWG-1206 - Investigate timeouts on buildbots [1/10]
- Had some mysterious timeouts on some of the buildbots
- Didn't manage to reproduce, will keep an eye out in case it happens again
* TCWG-1199, 1200 - LLVM 5.0.0 for ARM and AArch64 [1/10]
- RC1 is out, there are some failures in some libunwind and
sanitizer tests; reported upstream
* TCWG-1194 - [ARM GlobalISel] Support simple, static globals [4/10]
- Committed some simple stuff and sent a patch for upstream review
* TCWG-1209 - [MIR] Print ARM constant pools [1/10]
- Printing target-specific constant pools is trivial, but testing is
a bit problematic
- All current MIR tests read in and then print out the same MIR,
which means that we'd have to add support for target-specific constant
pools in the parser as well
- This is complicated by the fact that at a first glance the parser
doesn't seem to handle any other target-specific stuff and I'm not
sure it's ok to pull ARMConstantPool into it
* Misc [2/10]
- Mailing lists, code reviews, meetings
== Plan ==
* Figure out what to do about TCWG-1209
* More code reviews and global isel
# Progress #
* TCWG-1159,New design of GDB/GDBserver target description. [1/10]
Commit one patch of v3. No review comments. Usually it means I don't
review patches, so other people don't review my patches.
* PR 21555. [3/10]
Think it again, and fix it with a better approach. Patches are posted.
* PR 21717. [2/10]
Fix a bug on getting/setting FPSCR on VFPv2. I am surprised that we don't
find it before. Testing patches.
* TCWG-1162, Test GDB+OpenOCD with AArch64 boards. [1/10]
Blocked by OpenOCD bugs. Chat with OpenOCD maintainer to make sure
these bugs are opened in the right place.
* TCWG-561, [3/10]
I finish the patches, but not confident because I use copy-and-swap idiom
for the first time. Need more time to bake it, write unit tests, etc. Maybe,
still need to read "More effective C++" further.
* TCWG-1162, Test GDB+OpenOCD with AArch64 boards.
Blocked by OpenOCD bugs. Chat with OpenOCD maintainer to make sure
these bugs are opened in the right place. Matthew (who contributed OpenOCD
AArch64) pinged me on irc, but he lost connection immediately. Probably, he
contact me for the OpenOCD bugs.
* Think about presenting GDB target description work in Linaro SFO17,
may add some SVE stuff if possible, to make it more attractive.
# Plan #
* TCWG-1159,
* PR 21717, 21555,
* TCWG-561,
* Register the presentation for Linaro SFO17,
--
Yao Qi
== Progress ==
* [ARM GlobalISel] Support globals [6/10]
- This is going to be very hairy because of all the different
relocation models (PIC, ROPI etc), differences between ELF and MachO,
and differences between targets with MOVT or without it
- Started adding support for simple, statically linked globals, it
might take me a while to get all the pseudoinstructions right even for
this simple case
* Misc [4/10]
- Meetings, mailing lists, code reviews, buildbots
== Plan ==
* More GlobalISel
* More code reviews
== Progress ==
* Infrastructure/validation:
- minor fixes in the release jobs
* Benchmarking:
- fixes on reporting scripts
- using more iterations didn't produce more stable results (still noise)
- trying to reboot the boards before running the benchs
* GCC upstream validation:
- further reduced noise ("random" pass/failures)
- sent a patch to fix an aarch64 problem with -mstrict-align
* misc (conf-calls, meetings, emails, ....)
== Next ==
Holidays until August 21st
[TCWG-614] Range Thunks
Finally managed to get some review on the entirety of the Range Thunks
patches. Have reorganised the patches and wrote some documentation to
make it easier to review. Responded to all review comments so far.
Compiler-rt
A long tail of frustration.
Managed to get a hello world semi-hosting test case running on the
latest QEMU running newlib-nano. This was much more difficult than I
expected due to:
- The semihosting startup code of newlib does a semi-hosting call for
top of memory regardless of whether the heap and stack location have
been identified in a linker-script.
- The QEMU semihosting response to top of memory is not helpful
leaving the stack location in an invalid memory location (latest QEMU
requires emulation of a board and not a generic machine)
- QEMU doesn't data-abort when writing to a stack location, so my
return address is helpfully read back as 0x0
Worked around by providing a large enough memory size to QEMU that the
semihosting call for top of memory returns 0, allowing newlib to use
the values in the linker script. Will probably need to spend some time
to write my own startup code that just uses the linker script for the
heap and stack.
Building compiler-rt for v6-m and v7-m has been much more difficult
than I expected as well. I've managed to find a configuration that
works, although it relies on some experimental work in moving
compiler-rt to the runtimes directory.
Plans for next week:
- LLD is top priority
- Get testing for compiler-rt working via qemu on v7-m, the recipe
that works for build does not support testing. I've got to either
extract the cmake magic flags or find a way to plumb through the runes
that make the tests work to the recipe I've got.
- On holiday Thursday, Friday and the following Monday
