[llvm-dev] LLVM Weekly - #248, October 1st 2018

[Alex Bradbury via llvm-dev]

LLVM Weekly - #248, October 1st 2018
=====================================

If you prefer, you can read a HTML version of this email at
<http://llvmweekly.org/issue/248>.

Welcome to the two hundred and forty-eighth issue of LLVM Weekly, a weekly
newsletter (published every Monday) covering developments in LLVM, Clang, and
related projects. LLVM Weekly is brought to you by [Alex
Bradbury](https://www.linkedin.com/in/alex-bradbury/). Subscribe to future
issues at <http://llvmweekly.org> and pass it on to anyone else you think may
be interested. Please send any tips or feedback to <asb at asbradbury.org>, or
@llvmweekly or @asbradbury on Twitter.


## News and articles from around the web

The GSoC project to integrate libc++ and OpenMP packages into Debian's
llvm-toolchain package [received a
write-up](http://blog.llvm.org/2018/09/integration-of-libc-and-openmp-packages.html)
by Reshabh Sharma and Sylvestre Ledru.

The Visual C++ team blog has a new post by Stephen Kelly discussing [building
code with
Clang](https://blogs.msdn.microsoft.com/vcblog/2018/09/18/exploring-clang-tooling-part-0-building-your-code-with-clang/#comments),
featuring porting tips and a list of common issues that may be encountered by
MSVC users.

Version 1.4 of the clazy compiler plugin was
[released](https://github.com/KDE/clazy/tree/1.4). clazy provides a range of
over 50 Qt-related compiler warnings. As described in the
[changelog](https://github.com/KDE/clazy/blob/1.4/Changelog), v1.4 adds 10 new
checks.


## On the mailing lists

* Vedant Kumar has authored a new code size analysis tool and wonders if
there's [interest in
upstreaming](http://lists.llvm.org/pipermail/llvm-dev/2018-September/126501.html).

* Armando Montanez proposes a [llvm-tapi
tool](http://lists.llvm.org/pipermail/llvm-dev/2018-September/126472.html),
allowing "dynamic shared object stubbing".

* Fedor Sergeev started discussing [implementing OptBisect in the new pass
manager](http://lists.llvm.org/pipermail/llvm-dev/2018-September/126477.html)
and is seeking suggestions for improving the opt-bisect user experience.

* Dave Greene wonders if there is interest in a
[TrappingDebugCounter](http://lists.llvm.org/pipermail/llvm-dev/2018-September/126410.html)
to aid pass debugging.

* Alexandros Lamprineas is [seeking
feedback](http://lists.llvm.org/pipermail/llvm-dev/2018-September/126498.html)
on an RFC that proposes adding the ability to delay the folding of Phi
operands in InstCombine.

* Eli Friedman provides a helpful [guide to adding a simple backend-specific
intrinsic](http://lists.llvm.org/pipermail/llvm-dev/2018-September/126446.html).

* Andrew Savonichev shared an RFC on [implementing OpenCL builtin functions in
Clang](http://lists.llvm.org/pipermail/cfe-dev/2018-September/059500.html).
Anastasia Stulova responded with [detailed
feedback](http://lists.llvm.org/pipermail/cfe-dev/2018-September/059529.html)
on the proposed approach.

* György Orbán is gauging interest in [tools to convert a GCC compilation
database to Clang's format and convert Plist to
HTML](http://lists.llvm.org/pipermail/cfe-dev/2018-September/059503.html).


## LLVM commits

* AArch64 v8.5A patches have started to land, including MC layer support for
PSTATE manipulation, new FRINT instructions, a speculation barrier, prediction
invalidation instructions, branch target identification instructions, and
more.
[r343187](https://reviews.llvm.org/rL343187),
[r343209](https://reviews.llvm.org/rL343209),
[r343211](https://reviews.llvm.org/rL343211),
[r343214](https://reviews.llvm.org/rL343214),
[r343225](https://reviews.llvm.org/rL343225).

* llvm-exegesis gained support for benchmarking arbitrary user-provided code
snippets. [r342947](https://reviews.llvm.org/rL342947).

* HWASan will now display a list of recent stack frames when tag-mismatch is
detected on a stack address. [r342921](https://reviews.llvm.org/rL342923).

* MachineCopyPropagation's use of internal data structures was reworked in
order to improve compile time. [r342940](https://reviews.llvm.org/rL342940),
[r342942](https://reviews.llvm.org/rL342942).

* The ORC API now provided ThreadSafeModule and ThreadSafeContext wrappers to
support concurrent compilation of IR in the JIT.
[r343055](https://reviews.llvm.org/rL343055),
[r343058](https://reviews.llvm.org/rL343058)..

* LLVM gained support for AArch64 return address signing with DWARF.
[r343112](https://reviews.llvm.org/rL343112).


## Clang commits

* Clangd added initial support for cross-namespace global code completion.
[r343248](https://reviews.llvm.org/rL343248).

* Clang gained support for the OpenMP 5 requires directived and
`unified_address` clause. [r343063](https://reviews.llvm.org/rL343063).


## Other project commits

* The LLD COFF linker can now create range extension thunks for ARM.
[r342962](https://reviews.llvm.org/rL342962).

* The Python-implemented BSD archive parser in the LLDB repository now has an
interactive mode. [r343242](https://reviews.llvm.org/rL343242).