[llvm-dev] LLVM Weekly - #232, June 11th 2018

[Alex Bradbury via llvm-dev]

LLVM Weekly - #232, June 11th 2018
==================================

If you prefer, you can read a HTML version of this email at
<http://llvmweekly.org/issue/232>.

Welcome to the two hundred and thirty-second 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 ISO C++ Committee meeting recently took place in Rapperswil, Switzerland.
Several committee members have shared a
[detailed write-up](https://old.reddit.com/r/cpp/comments/8prqzm/2018_rapperswil_iso_c_committee_trip_report/)
on Reddit.

The next LLVM Social in Shanghai has been
[announced](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123775.html)
for July 1st.

[Zig](https://ziglang.org/) is an interesting LLVM-based language which has
been mentioned in LLVM Weekly previously, and aims to be a better C. The
author is moving to working full-time on Zig and is [seeking
donations](https://andrewkelley.me/post/full-time-zig.html).


## On the mailing lists

* Johannes Doerfert proposes [abstract parallel IR
optimisations](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123841.html)
in a new RFC.

* Hans Wennborg has proposed the [schedule for the 7.0.0
release](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123843.html). This
would see the branch taking place on 1st August with RC1 soon after, RC2
coming on the 22nd August, and the final tag on 5th September.

* Graham Hunter has shared an [updated
RFC](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123780.html) on
supporting SIMD instruction sets with variable vector lengths (e.g. SVE).
There is also a sub-thread discussing support for the RISC-V vector extension.

* Tanya Lattner is
[looking](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123781.html) for
booth volunteers for the Grace Hopper Conference in Houston in September.

* Brian Gesiak
[queries](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123769.html) the
current state of LLD support for Mach-O. The thread received a number of
responses from active LLD developers.

* Robin Eklind has created a [BNF grammar for LLVM IR
assembly](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123851.html).

* Chijun Sima has shared an RFC on [a new dominator tree updater
API](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123883.html).

* Fedor Sergeev has authored an RFC on [a new pass execution instrumentation
interface](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123835.html).
This aims to allow the easy implementation of facilities such as
`-print-after`, `-opt-bisect-limit`, etc. Importantly, it aims to be
compatible with the new pass manager.

* Masaki Arai is looking for feedback on an [RFC to port MachinePipeliner to
AArch64+SVE](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123884.html).

* Nicolai Hähnle is [drawing
attention](http://lists.llvm.org/pipermail/llvm-dev/2018-June/123915.html) to
recent work which generalizes the "searchable tables" backend of TableGen.


## LLVM commits

* An initial set of optimisation remarks has been added to the shrink-wrapping
pass. [r333972](https://reviews.llvm.org/rL333972).

* The SETCCE SelectionDAG node has been removed in favour of SETCCCARRY.
[r333939](https://reviews.llvm.org/rL333939).

* The semantics of NAME in TableGen have been streamlined.
[r333900](https://reviews.llvm.org/rL333900).

* Documentation was added for masked vector expanding load and compressing
store intrinsics. [r334075](https://reviews.llvm.org/rL334075).

* The 'li' pseudo instruction is now supported by the RISC-V MC assembly
parser. [r334203](https://reviews.llvm.org/rL334203).


## Clang commits

* Implementation of clang-doc continues with the introduction of the 'reducer'
portion of the frontend framework.
[r333932](https://reviews.llvm.org/rL333932).

* Bittest intrinsics have been implemented generically for non-x86 platforms.
[r334059](https://reviews.llvm.org/rL334059).


## Other project commits

* libFuzzer gained an initial implementation of `-data_flow_trace`.
[r334058](https://reviews.llvm.org/rL334058).

* LLD now supports multi-GOT for MIPS. This allows large applications such as
LLVM+Clang to be linked. [r334390](https://reviews.llvm.org/rL334390).