Alex Bradbury via llvm-dev
2016-Sep-19 12:17 UTC
[llvm-dev] LLVM Weekly - #142, Sep 19th 2016
LLVM Weekly - #142, Sep 19th 2016 ================================ If you prefer, you can read a HTML version of this email at <http://llvmweekly.org/issue/142>. Welcome to the one hundred and forty-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](http://asbradbury.org). 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 new board of directors for the LLVM Foundation has [been announced](http://lists.llvm.org/pipermail/llvm-foundation/2016-September/000129.html). It consists of 8 members (5 continuing and 3 new members). Congratulations to all those elected. Dean Michael Berris is [organising another LLVM developer meet-up in Sydney](http://lists.llvm.org/pipermail/llvm-dev/2016-September/104839.html). This will take place on October 11th. Neil Henning has shared the [next installment](http://www.duskborn.com/adding-type-identifiers-mpc-llvm-for-the-neil-language-3/) of his blog series on compiling the toy 'Neil' language using LLVM. ## On the mailing lists * Chris Lattner has [restarted](http://lists.llvm.org/pipermail/llvm-dev/2016-September/104778.html) the discussion on moving LLVM projects to the Apache license. The current proposal involves an exception to allow use of LLVM code with GPLv2 software. * Hemant Kulkarni has posted an RFC on [disassembling mixed ARM and thumb in a single ELF](http://lists.llvm.org/pipermail/llvm-dev/2016-September/104942.html) by making use of information in the `.ARM.attributes` section. * Can def-use chains be used for static data dependency analysis? As John Criswell [explains](http://lists.llvm.org/pipermail/llvm-dev/2016-September/104919.html), yes as long as everything is in virtual registers. Otherwise you'll want to use a iterative data-flow analysis and alias analysis. * Chris Lattner is [not convinced](http://lists.llvm.org/pipermail/llvm-dev/2016-September/104828.html) on the proposal to add support for specifying named regex patterns in FileCheck. He proposes instead just having several baked-in 'modes', that expose some predefined patterns. * Many people are not aware of this limitation so I thought it was worth signal-boosting this post. [Comments on patch sent by email won't always be picked up by Phabricator](http://lists.llvm.org/pipermail/llvm-dev/2016-September/104881.html). Specifically, Phabricator will drop email responses with an inline response. Top-posting seems to mostly work. * Vivek Pandya has posted an RFC on [an extension to existing register rematerialisation support](http://lists.llvm.org/pipermail/llvm-dev/2016-September/104881.html). ## LLVM commits * MCInstrDesc gained a new field, `isAdd`. For Hexagon, this is used to identify loop induction statements. [r281304](http://reviews.llvm.org/rL281304). * llvm-objdump gained the `--start-address` and `--stop-address` options. [r281232](http://reviews.llvm.org/rL281232). * There is now a new metadata representation for global variables. [r281284](http://reviews.llvm.org/rL281284). * All functions related to branch analysis have been renamed to conform to the LLVM coding style. [r281535](http://reviews.llvm.org/rL281535). * The documentation on compiling CUDA with Clang has been updated to discuss STL support and the differences between nvcc and clang. [r281573](http://reviews.llvm.org/rL281573). ## Clang commits * A new command-line option, `-fdiagnostics-show-hotness` was added. This means any optimisation remarks will also include hotness information if available from PGO. [r281276](http://reviews.llvm.org/rL281276). * clang-tblgen gained a model to generate reference documentation for warning and remark flags. [r281192](http://reviews.llvm.org/rL281192). * A new clang-tidy check, 'misc-use-after-move' has been introduced. This warns if an object is used after it has been moved. [r281453](http://reviews.llvm.org/rL281453). ## Other project commits * Work in the direction of supporting breakpoint save and restore in LLDB has been committed. [r281273](http://reviews.llvm.org/rL281273). * Work has started to use lit for the LLDB test suite. [r281651](http://reviews.llvm.org/rL281651).