[ACTIVITY] report week ending 18 May

[Peter Maydell]

Progress: [short week, 3 days]
* VIRT-65 [QEMU upstream maintainership]
+ code review
- make system registers visible via gdbstub
- Richard's patches to fix various softfloat issues
* VIRT-164 [improve Cortex-M emulation]
+ MPC emulation:
- rebased and fixed up conflicts with a different series that
touched the same parts of the memory system
- realised that passing txattrs to IOMMUs means we need to
change the notifier API; came up with a plan to handle this
by using "IOMMU indexes" analogous to our existing TCG MMU
indexes. Updated everything to the new API that comes out
of that approach.
- started on tidying up the final loose ends; hope to have
something I can send to the list early next week

thanks
-- PMM

[Peter Smith]

[Activity]

[TCWG-1319] Link AOSP with LLD.
Closed this out as I've gone as far as I can profitably go without
being an Android expert.
- With trunk LLD I can now link and boot AOSP with LLD without any
use_clang_lld=false on both Arm and AArch64 emulators. I also managed
to get it to boot on a Hikey960 (aarch64).
- Communicated recent additions to LLD in aid of building AOSP, and
extra command line options needed to the Google team.

Landed support for GCC inline assembly constraint S in LLVM.

Some comments on LTO + linker script proposal on llvm-dev mailing list.

Started thinking in more detail about ICF=safe.
- Decided that LLVM was a better place to do this than clang after
attempting to use libtooling.
- There is an existing LLVM pass called merge functions that does what
ICF does but at the LLVM IR level
-- This is off by default, maybe worth looking at as part of LTO and
code-size reductions.
- Started to write a prototype pass that uses
Function::isAddressTaken() although I think that this may give me too
pessimistic a result.

Peter