LLVM 19.0.0git Release Notes

Warning

These are in-progress notes for the upcoming LLVM 19 release. Release notes for previous releases can be found on the Download Page.

Introduction

This document contains the release notes for the LLVM Compiler Infrastructure, release 19.0.0git. 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 Discourse forums is a good place to ask them.

Note that if you are reading this file from a Git 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

Update on required toolchains to build LLVM

Changes to the LLVM IR

Changes to LLVM infrastructure

Changes to building LLVM

Changes to TableGen

  • We can define type aliases via new keyword deftype.

Changes to Interprocedural Optimizations

Changes to the AArch64 Backend

Changes to the AMDGPU Backend

Changes to the ARM Backend

Changes to the AVR Backend

Changes to the DirectX Backend

Changes to the Hexagon Backend

Changes to the LoongArch Backend

Changes to the MIPS Backend

Changes to the PowerPC Backend

Changes to the RISC-V Backend

  • Added full support for the experimental Zabha (Byte and Halfword Atomic Memory Operations) extension.

  • Added assembler/disassembler support for the experimenatl Zalasr (Load-Acquire and Store-Release) extension.

  • The names of the majority of the S-prefixed (supervisor-level) extension names in the RISC-V profiles specification are now recognised.

  • Codegen support was added for the Zimop (May-Be-Operations) extension.

  • The experimental Ssnpm, Smnpm, Smmpm, Sspm, and Supm 0.8.1 Pointer Masking extensions are supported.

  • The experimental Ssqosid extension is supported.

  • Zacas is no longer experimental.

Changes to the WebAssembly Backend

Changes to the Windows Target

Changes to the X86 Backend

Changes to the OCaml bindings

Changes to the Python bindings

Changes to the C API

  • Added LLVMGetBlockAddressFunction and LLVMGetBlockAddressBasicBlock functions for accessing the values in a blockaddress constant.

Changes to the CodeGen infrastructure

Changes to the Metadata Info

Changes to the Debug Info

Changes to the LLVM tools

  • llvm-nm and llvm-objdump can now print symbol information from linked WebAssembly binaries, using information from exports or the “name” section for functions, globals and data segments. Symbol addresses and sizes are printed as offsets in the file, allowing for binary size analysis. Wasm files using reference types and GC are also supported (but also only for functions, globals, and data, and only for listing symbols and names).

  • llvm-ar now utilizes LLVM_DEFAULT_TARGET_TRIPLE to determine the archive format if it’s not specified with the --format argument and cannot be inferred from input files.

  • llvm-objcopy now supports --set-symbol-visibility and --set-symbols-visibility options for ELF input to change the visibility of symbols.

Changes to LLDB

Changes to Sanitizers

Other Changes

External Open Source Projects Using LLVM 19

  • A project…

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 Git 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.

If you have any questions or comments about LLVM, please feel free to contact us via the Discourse forums.