============================ LLVM |release| Release Notes ============================ .. contents:: :local: .. only:: PreRelease .. warning:: These are in-progress notes for the upcoming LLVM |version| 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 |release|. 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 ================================================= .. NOTE For small 1-3 sentence descriptions, just add an entry at the end of this list. If your description won't fit comfortably in one bullet point (e.g. maybe you would like to give an example of the functionality, or simply have a lot to talk about), see the `NOTE` below for adding a new subsection. * ... Update on required toolchains to build LLVM ------------------------------------------- Changes to the LLVM IR ---------------------- * Typed pointers are no longer supported. See the `opaque pointers `__ documentation for migration instructions. * The ``nofpclass`` attribute was introduced. This allows more optimizations around special floating point value comparisons. Changes to building LLVM ------------------------ Changes to TableGen ------------------- Changes to Interprocedural Optimizations ---------------------------------------- Changes to the AArch64 Backend ------------------------------ Changes to the AMDGPU Backend ----------------------------- Changes to the ARM Backend -------------------------- - The hard-float ABI is now available in Armv8.1-M configurations that have integer MVE instructions (and therefore have FP registers) but no scalar or vector floating point computation. 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 ----------------------------- * Assembler support for version 1.0.1 of the Zcb extension was added. * Zca, Zcf, and Zcd extensions were upgraded to version 1.0.1. * vsetvli intrinsics no longer have side effects. They may now be combined, moved, deleted, etc. by optimizations. * Adds support for the vendor-defined XTHeadBa (address-generation) extension. * Adds support for the vendor-defined XTHeadBb (basic bit-manipulation) extension. * Adds support for the vendor-defined XTHeadBs (single-bit) extension. * Adds support for the vendor-defined XTHeadCondMov (conditional move) extension. * Adds support for the vendor-defined XTHeadMac (multiply-accumulate instructions) extension. * Added support for the vendor-defined XTHeadMemPair (two-GPR memory operations) extension disassembler/assembler. * Added support for the vendor-defined XTHeadMemIdx (indexed memory operations) extension disassembler/assembler. * Support for the now-ratified Zawrs extension is no longer experimental. * Adds support for the vendor-defined XTHeadCmo (cache management operations) extension. * Adds support for the vendor-defined XTHeadSync (multi-core synchronization instructions) extension. * Added support for the vendor-defined XTHeadFMemIdx (indexed memory operations for floating point) extension. Changes to the WebAssembly Backend ---------------------------------- * ... Changes to the Windows Target ----------------------------- Changes to the X86 Backend -------------------------- Changes to the OCaml bindings ----------------------------- Changes to the C API -------------------- * ``LLVMContextSetOpaquePointers``, a temporary API to pin to legacy typed pointer, has been removed. * Functions for adding legacy passes like ``LLVMAddInstructionCombiningPass`` have been removed. Changes to the FastISel infrastructure -------------------------------------- * ... Changes to the DAG infrastructure --------------------------------- Changes to the Metadata Info --------------------------------- Changes to the Debug Info --------------------------------- * The DWARFv5 feature of attaching ``DW_AT_default_value`` to defaulted template parameters will now be available in any non-strict DWARF mode and in a wider range of cases than previously. (`D139953 `_, `D139988 `_) * The ``DW_AT_name`` on ``DW_AT_typedef``\ s for alias templates will now omit defaulted template parameters. (`D142268 `_) * The experimental ``@llvm.dbg.addr`` intrinsic has been removed (`D144801 `_). IR inputs with this intrinsic are auto-upgraded to ``@llvm.dbg.value`` with ``DW_OP_deref`` appended to the ``DIExpression`` (`D144793 `_). Changes to the LLVM tools --------------------------------- Changes to LLDB --------------------------------- * In the results of commands such as `expr` and `frame var`, type summaries will now omit defaulted template parameters. The full template parameter list can still be viewed with `expr --raw-output`/`frame var --raw-output`. (`D141828 `_) Changes to Sanitizers --------------------- Other Changes ------------- External Open Source Projects Using LLVM 15 =========================================== * 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 `_.