LLVM Weekly - #356, October 26th 2020

Welcome to the three hundred and fifty-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. Subscribe to future issues at https://llvmweekly.org and pass it on to anyone else you think may be interested. Please send any tips or feedback to asb@asbradbury.org, or @llvmweekly or @asbradbury on Twitter.

News and articles from around the web

Renato Golin has blogged about using MLIR for Verona - a research programming language exploring the concept of concurrent ownership.

On the mailing lists

• Hans Wennborg announced that after six years and twelve major releases, he is stepping down as release manager. Tom Stellard has kindly offered to take over. Thank you Hans for performing this vital role for so long!

• Luis Dionne outlined a vision for building the runtimes, noting that currently building the runtimes can be a fairly complex endeavour.

• Paul C. Anagnostopoulos has posted the first of hopefully many irregularly scheduled TableGen update newsletters, outlining recent TableGen enhancements and changes.

• ORC JIT Weekly #25 is out covering the Orc library breakup and an overview of TargetProcessControl.

• Nicolai Hähnle started a design discussion about the recently committed CfgTraits/CfgInterface infrastructure, noting some design concerns that were brought up post-commit.

• Jonas Devlieghere shared an RFC on segmented address space support in LLDB.

• Louis Dionne posted a heads-up on workflow changes for testing header-only libc++ changes.

• Orlando Cazalet-Hyams followed up with notes from the optimised code debugging experience round table at the LLVM Dev Meeting.

• Paul C. Anagnostopoulos is seeking opinions on adding boolean literals to the TableGen language.

• Simon Moll shared notes from a recent vector predication round table.

• Gábor Márton is seeking feedback on a proposal to add attributes to enhance/configure Clang static analyzer's analyses.

• Eric Astor provided an update on the llvm-ml project to add native MASM (Microsoft Macro Assembler) support.

• Maksim Panchenko posted an RFC on adding the BOLT binary optimisation framework to LLVM.

LLVM commits

• The mustprogress attribute was added. 1e55cf7, 595c615.

• A new utility was added to launch tests on a target remotely. dc98923.

• MC layer support for X86 user interrupt instructions was added. be39a6f.

• Orc gained new APIs to support resource tracking and removal and the Kaleidoscope and BuildingAJIT tutorials were updated to OrcV2. 0aec49c, ad92f16.

• The nosync, nofree and willreturn attributes are now set by default for intrinsics. fbfb1c7.

• The CfgTraits abstraction was introduced, aiming to simplify writing algorithms that are generic over the type of CFG. c0cdd22.

• ValueTracking for getelementptr was improved. ee6abef.

• A new post-isel optimisation pass was introduced for AArch64 GlobalISel. 0f0fd38.

Clang commits

• Support was enabled for #pragma STDC FENV_ACCESS. 2e204e2.

• Support was added for passing union types on X86 in the previous (incorrect) manner, for backwards compatibility. 774ab60.

• As part of the C++20 implementation effort, basic frontend support was added for class types as non-type template parameters. ba4768c.

Other project commits

• libFuzzer gained a new -print_full_coverage flag that will print all branches (regardless of coverage status) in an easy-to-parse format. dc62d5e.

• Flang's compiler driver development continues with the addition of infrastructure for file I/O and frontend actions. 4c5906c.

• LLDB's documentation has started to collect links to external resources on how to use LLDB. de6f3d1.

• An converter from the MLIR Async dialect to LLVM coroutines was added. f8fcff5.