Alex Bradbury via llvm-dev
2018-Apr-23 19:18 UTC
[llvm-dev] LLVM Weekly - #225, Apr 23rd 2018
LLVM Weekly - #225, Apr 23rd 2018 ================================ If you prefer, you can read a HTML version of this email at <http://llvmweekly.org/issue/225>. Welcome to the two hundred and twenty-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. For those of you attending the Barcelona RISC-V Workshop May 7th-10th, be sure to come along to [my short tutorial session on RISC-V LLVM](https://riscv.org/2018/04/risc-v-workshop-in-barcelona-agenda/). ## News and articles from around the web As usual, EuroLLVM was a huge success. The LLVM community is again indebted to the organisers and presenters for their efforts. Talks were recorded, and I will of course update you when they are available. The LLVM Foundation Board have put together a status and overview page of the [LLVM Relicensing effort](http://llvm.org/foundation/relicensing/). This includes a list of next steps and schedule estimate. ## On the mailing lists * Manoj Gupta kicked off an RFC discussion on [implementing -fno-delete-null-pointer-checks in Clang](http://lists.llvm.org/pipermail/llvm-dev/2018-April/122632.html). This flag is used wen building the Linux kernel. This flag has the semantics "Assume that programs cannot safely dereference null pointers, and that no code or data element resides at address zero". The proposal has triggered quite a lot of discussion so far. * Jessica Paquette [proposes](http://lists.llvm.org/pipermail/llvm-dev/2018-April/122705.html) turning the MachineOutliner on by default in AArch64 under `-Oz`. As Jessica explains, the hope is that the same outlining algorithm and interface can be used for the proposed IR-level outlining pass. On CTMark, outlining is giving an extra 4.4% geomean text size reduction for the cost of a geomean 1.1% compile-time overhead. * Alex L [announces](http://lists.llvm.org/pipermail/cfe-dev/2018-April/057668.html) that Apple have decided to switch focus from the libclang-based tooling infrastructure in order to join forces on Clangd development. They intend to contribute towards making Clangd faster, more capable, and more efficient. * Pavel Labath [suggests](http://lists.llvm.org/pipermail/lldb-dev/2018-April/013550.html) making use of LLD in LLDB tests in order to make them host independent. * John Brawn has shared an RFC on [making GVN (Global Value Numbering) able to visit the same block more than once](http://lists.llvm.org/pipermail/llvm-dev/2018-April/122628.html). Daniel Berlin [suggests](http://lists.llvm.org/pipermail/llvm-dev/2018-April/122656.html) that GVN might not be the right place for the transformation John is trying to achieve, but recognises there aren't particularly good alternative options currently. ## LLVM commits * A new `update_mca_test_checks.py` script has been added, to aid regenerating llvm-mca tests. [r330246](http://reviews.llvm.org/rL330246). * MC layer support for AArch64 SVE continues to develop. [r330108](http://reviews.llvm.org/rL330108), [r330116](http://reviews.llvm.org/rL330116), and more. * The X86 backend gained support for new X86 'WaitPKG' instructions: umonitor, umwait, and tpause. [r330462](http://reviews.llvm.org/rL330462). ## Clang commits * The `-falign-functions` flag is now supported. [r330378](http://reviews.llvm.org/rL330378). * The ARM Clang driver will now add target features explicitly rather than rewriting the triple. [r330169](http://reviews.llvm.org/rL330169). ## Other project commits * LLD now supports profile-guided section layout using the Call-Chain Clustering heuristic. [r330234](http://reviews.llvm.org/rL330234). * libcxxabi now uses `__libcpp_atomic_*` function calls rather than `__sync_*`. [r330162](http://reviews.llvm.org/rL330162). * The LLDB test suite is now run using Lit. [r330275](http://reviews.llvm.org/rL330275).
Apparently Analagous Threads
- [LLVMdev] To APR Or Not To APR. That is the question.
- [LLVMdev] To APR Or Not To APR. That is the question.
- [LLVMdev] To APR Or Not To APR. That is the question.
- [LLVMdev] To APR Or Not To APR. That is the question.
- [LLVMdev] To APR Or Not To APR. That is the question.