LLVM 5.0.0 Release Notes


These are in-progress notes for the upcoming LLVM 5 release. Release notes for previous releases can be found on the Download Page.


This document contains the release notes for the LLVM Compiler Infrastructure, release 5.0.0. Here we describe the status of LLVM, including major improvements from the previous release, improvements in various subprojects of LLVM, and some of the current users of the code. All LLVM releases may be downloaded from the LLVM releases web site.

For more information about LLVM, including information about the latest release, please check out the main LLVM web site. If you have questions or comments, the LLVM Developer’s Mailing List is a good place to send them.

Note that if you are reading this file from a Subversion checkout or the main LLVM web page, this document applies to the next release, not the current one. To see the release notes for a specific release, please see the releases page.

Non-comprehensive list of changes in this release

  • LLVM’s WeakVH has been renamed to WeakTrackingVH and a new WeakVH has been introduced. The new WeakVH nulls itself out on deletion, but does not track values across RAUW.
  • A new library named BinaryFormat has been created which holds a collection of code which previously lived in Support. This includes the file_magic structure and identify_magic functions, as well as all the structure and type definitions for DWARF, ELF, COFF, WASM, and MachO file formats.
  • The tool llvm-pdbdump has been renamed llvm-pdbutil to better reflect its nature as a general purpose PDB manipulation / diagnostics tool that does more than just dumping contents.
  • The BBVectorize pass has been removed. It was fully replaced and no longer used back in 2014 but we didn’t get around to removing it. Now it is gone. The SLP vectorizer is the suggested non-loop vectorization pass.

Changes to the LLVM IR

  • The datalayout string may now indicate an address space to use for the pointer type of alloca rather than the default of 0.
  • Added speculatable attribute indicating a function which does has no side-effects which could inhibit hoisting of calls.

Changes to the ARM Backend

During this release ...

Changes to the MIPS Target

During this release ...

Changes to the PowerPC Target

During this release ...

Changes to the X86 Target

  • Added initial AMD Ryzen (znver1) scheduler support.
  • Added support for Intel Goldmont CPUs.
  • Add support for avx512vpopcntdq instructions.
  • Added heuristics to convert CMOV into branches when it may be profitable.
  • More aggressive inlining of memcmp calls.
  • Improve vXi64 shuffles on 32-bit targets.
  • Improved use of PMOVMSKB for any_of/all_of comparision reductions.
  • Improved Silvermont, Sandybridge, and Jaguar (btver2) schedulers.
  • Improved support for AVX512 vector rotations.
  • Added support for AMD Lightweight Profiling (LWP) instructions.

Changes to the AMDGPU Target

  • Initial gfx9 support

Changes to the AVR Target

During this release ...

Changes to the OCaml bindings

During this release ...

Changes to the C API

  • Deprecated the LLVMAddBBVectorizePass interface since the BBVectorize pass has been removed. It is now a no-op and will be removed in the next release. Use LLVMAddSLPVectorizePass instead to get the supported SLP vectorizer.

Additional Information

A wide variety of additional information is available on the LLVM web page, in particular in the documentation section. The web page also contains versions of the API documentation which is up-to-date with the Subversion version of the source code. You can access versions of these documents specific to this release by going into the llvm/docs/ directory in the LLVM tree.

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