[llvm-dev] LLVM Weekly - #235, July 2nd 2018

[Alex Bradbury via llvm-dev]

LLVM Weekly - #235, July 2nd 2018
=================================

If you prefer, you can read a HTML version of this email at
<http://llvmweekly.org/issue/235>.

Welcome to the two hundred and thirty-fifth 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 [call for
papers](http://lists.llvm.org/pipermail/llvm-dev/2018-June/124370.html) has
been issued for the 2018 LLVM Developers' Meeting. Deadline for submission is
July 30th.

LLVM 6.0.1-final [has been
tagged](http://lists.llvm.org/pipermail/llvm-dev/2018-June/124318.html).

The next London LLVM social will be held on [Thursday July
19th](http://lists.llvm.org/pipermail/llvm-dev/2018-June/124364.html) at
6.30pm.


## On the mailing lists

* Zachary Turner has started an RFC on
[libtrace](http://lists.llvm.org/pipermail/lldb-dev/2018-June/013826.html), a
lightweight LLVM-based ptracer. The thread details how it has a much narrower
focus than LLDB, although obviously having some overlap.

* Clement Courbet
[proposes](http://lists.llvm.org/pipermail/llvm-dev/2018-June/124343.html)
extending superword-level parallelism to vectorize bit-parallel operations
using general purpose registers. All discussion on this idea so far is [on
phabricator](https://reviews.llvm.org/D48725).

* Hideki Saito has started an RFC discussion on [legalizing veclib
calls](http://lists.llvm.org/pipermail/llvm-dev/2018-June/124357.html).


## LLVM commits

* Debug locations are no longer attached to ConstantSDNode and ConstandSDFPNode.
This change was
[discussed](http://lists.llvm.org/pipermail/llvm-dev/2018-June/124164.html) on
the mailing list.
[r335497](https://reviews.llvm.org/rL335497).

* FileCheck now supports a CHECK-EMPTY directive for checking blank lines.
[r335613](https://reviews.llvm.org/rL335613).

* The RISC-V backend gained a machine function pass to merge base+offset in
global address references. This replaces the previous peephole in
RISCVISelDAGToDAG. [r335786](https://reviews.llvm.org/rL335786).

* The X86 backend gained further support for the x86-64 large and medium PIC
code models. [r335508](https://reviews.llvm.org/rL335508).

* The new loop unswitching pass now handles nontrivial unswitching, bringing
it roughly on par with the previous pass.
[r335553](https://reviews.llvm.org/rL335553).

* ARM gained a pass to pattern-match IR in order to select ACLE DSP
intrinsics. [r333850](https://reviews.llvm.org/rL333850).

* Very initial enablement for Armv8.4-A has landed.
[r335953](https://reviews.llvm.org/rL335953),
[r335962](https://reviews.llvm.org/rL335962).


## Clang commits

* Clang now supports control-flow integrity for indirect calls via a member
function pointer. [r335569](https://reviews.llvm.org/rL335569).

* Informative diagnostics for missing template keywords are given in more
cases. [r335687](https://reviews.llvm.org/rL335687),
[r335699](https://reviews.llvm.org/rL335699).


## Other project commits

* The Harris Corner Detection kernel was added to the LLVM test suite.
[r335611](https://reviews.llvm.org/rL335611).

* LLD gained support for OVERLAYs in linker scripts.
[r335714](https://reviews.llvm.org/rL335714).