[llvm-dev] LLVM Weekly - #346, August 17th 2020

[Alex Bradbury via llvm-dev]

LLVM Weekly - #346, August 17th 2020
====================================

If you prefer, you can read a HTML version of this email at
<http://llvmweekly.org/issue/346>.

Welcome to the three hundred and forty-sixth 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 submission deadline for the LLVM-HPC2020 workshop at SC20 is approaching,
with proposals [due by September
1](http://lists.llvm.org/pipermail/llvm-dev/2020-August/144325.html).

A new talk from Nick Desaulniers provides an
[introduction to the architecture of
LLVM](https://www.youtube.com/watch?v=bUTXhcf_aNc).


## On the mailing lists

* Carlos Enciso [proposed llvm-diva for inclusion in
LLVM](http://lists.llvm.org/pipermail/llvm-dev/2020-August/144174.html). The
Debug Information Visual Analyzer was developed at Sony to help visualise
debug info at a high level. It also provides a comparison mode.

* Jeroen Dobbelaere reports that the previously discussed full restrict
patches are [now almost ready for
review](http://lists.llvm.org/pipermail/llvm-dev/2020-August/144332.html), and
seeks feedback on the current plan for moving forwards.

* Discussion continued on support for zeroing caller saved regs with David
Chisnall [further discussing its security
properties](http://lists.llvm.org/pipermail/llvm-dev/2020-August/144182.html).

* David Spickett posted an RFC on [supporting AArch64's tagging extension in
LLDB](http://lists.llvm.org/pipermail/lldb-dev/2020-August/016402.html).

* OT JIT Weekly #20 [is
out](http://lists.llvm.org/pipermail/llvm-dev/2020-August/144368.html), with
the headline item being that llvm-jitlink moved to the TargetProcessControl
API for memory allocation and access.


## LLVM commits

* Initial backend infrastructure was added for `-mtune`, represented as a
"tune-cpu" function attribute.
[c7a0b26](https://reviews.llvm.org/rGc7a0b2684f7).

* Support was added for emitting the GNU `.debug_macro` extension.
[e2f3240](https://reviews.llvm.org/rGe2f32404727).

* UpdateTestChecks was modified to match most uses of temporary named values
in the IR via regular expressions.
[97ce7fd](https://reviews.llvm.org/rG97ce7fd89fc).

* BranchProbabilityInfo's static heuristics for integer comparisons were
improved, matching GCC's. [385c9d6](https://reviews.llvm.org/rG385c9d673f2).

* ORC gained a JITLink-compatible remote memory-manager.
[30c4561](https://reviews.llvm.org/rG30c4561e36e).

* The tablegen asm matcher backend will now allow mnemonics with uppercase
letters to be matched. [3cf7efe](https://reviews.llvm.org/rG3cf7efec986).


## Clang commits

* clang-tidy's modernize-user-trailing-return-type gained support for C++20
concepts and decltype. [3450533](https://reviews.llvm.org/rG345053390ac).

* Support was added for `-fno-eliminate-unused-debug-types`.
[4f2ad15](https://reviews.llvm.org/rG4f2ad15db53).

* Clang will now default to using /usr/bin/ld on Solaris.
[f59bec7](https://reviews.llvm.org/rGf59bec7acb8).


## Other project commits

* An OpenACC MLIR dialect was introduced.
[4225e7f](https://reviews.llvm.org/rG4225e7fa34f).

* LLVM's libc gained `strtok` and `strtok_r` implementations.
[667843c](https://reviews.llvm.org/rG667843cc07c).

* std::visit benchmarks were added to libcxx and its implementation was
optimised. [c6f5137](https://reviews.llvm.org/rGc6f51377e12),
[a175a96](https://reviews.llvm.org/rGa175a96517c).

* lld-macho continues development with support for dynamic linking of
thread-locals, `-force_load`, and other features.
[3c9100f](https://reviews.llvm.org/rG3c9100fb785),
[437e6bd](https://reviews.llvm.org/rG437e6bd286a).

* MLIR's pattern rewrite infrastructure was documented.
[f7a1347](https://reviews.llvm.org/rGf7a13479b80).

* A libomptarget host plugin for amdgpu was added.
[d0b3129](https://reviews.llvm.org/rGd0b312955f1).