1============================ 2LLVM |release| Release Notes 3============================ 4 5.. contents:: 6 :local: 7 8.. only:: PreRelease 9 10 .. warning:: 11 These are in-progress notes for the upcoming LLVM |version| release. 12 Release notes for previous releases can be found on 13 `the Download Page <https://releases.llvm.org/download.html>`_. 14 15 16Introduction 17============ 18 19This document contains the release notes for the LLVM Compiler Infrastructure, 20release |release|. Here we describe the status of LLVM, including major improvements 21from the previous release, improvements in various subprojects of LLVM, and 22some of the current users of the code. All LLVM releases may be downloaded 23from the `LLVM releases web site <https://llvm.org/releases/>`_. 24 25For more information about LLVM, including information about the latest 26release, please check out the `main LLVM web site <https://llvm.org/>`_. If you 27have questions or comments, the `LLVM Developer's Mailing List 28<https://lists.llvm.org/mailman/listinfo/llvm-dev>`_ is a good place to send 29them. 30 31Note that if you are reading this file from a Git checkout or the main 32LLVM web page, this document applies to the *next* release, not the current 33one. To see the release notes for a specific release, please see the `releases 34page <https://llvm.org/releases/>`_. 35 36Non-comprehensive list of changes in this release 37================================================= 38.. NOTE 39 For small 1-3 sentence descriptions, just add an entry at the end of 40 this list. If your description won't fit comfortably in one bullet 41 point (e.g. maybe you would like to give an example of the 42 functionality, or simply have a lot to talk about), see the `NOTE` below 43 for adding a new subsection. 44 45* ... 46 47Update on required toolchains to build LLVM 48------------------------------------------- 49 50With LLVM 15.x we will raise the version requirements of the toolchain used 51to build LLVM. The new requirements are as follows: 52 53* GCC >= 7.1 54* Clang >= 5.0 55* Apple Clang >= 9.3 56* Visual Studio 2019 >= 16.7 57 58In LLVM 15.x these requirements will be "soft" requirements and the version 59check can be skipped by passing -DLLVM_TEMPORARILY_ALLOW_OLD_TOOLCHAIN=ON 60to CMake. 61 62With the release of LLVM 16.x these requirements will be hard and LLVM developers 63can start using C++17 features, making it impossible to build with older 64versions of these toolchains. 65 66Changes to the LLVM IR 67---------------------- 68 69Changes to building LLVM 70------------------------ 71 72* Omitting ``CMAKE_BUILD_TYPE`` when using a single configuration generator is now 73 an error. You now have to pass ``-DCMAKE_BUILD_TYPE=<type>`` in order to configure 74 LLVM. This is done to help new users of LLVM select the correct type: since building 75 LLVM in Debug mode is very resource intensive, we want to make sure that new users 76 make the choice that lines up with their usage. We have also improved documentation 77 around this setting that should help new users. You can find this documentation 78 `here <https://llvm.org/docs/CMake.html#cmake-build-type>`_. 79 80Changes to TableGen 81------------------- 82 83Changes to the AArch64 Backend 84------------------------------ 85 86Changes to the AMDGPU Backend 87----------------------------- 88 89* ... 90 91Changes to the ARM Backend 92-------------------------- 93 94* Added support for the Armv9-A, Armv9.1-A and Armv9.2-A architectures. 95* Added support for the Armv8.1-M PACBTI-M extension. 96* Added support for the Armv9-A, Armv9.1-A and Armv9.2-A architectures. 97* Added support for the Armv8.1-M PACBTI-M extension. 98* Removed the deprecation of ARMv8-A T32 Complex IT blocks. No deprecation 99 warnings will be generated and -mrestrict-it is now always off by default. 100 Previously it was on by default for Armv8 and off for all other architecture 101 versions. 102 103Changes to the AVR Backend 104-------------------------- 105 106* ... 107 108Changes to the Hexagon Backend 109------------------------------ 110 111* ... 112 113Changes to the MIPS Backend 114--------------------------- 115 116* ... 117 118Changes to the PowerPC Backend 119------------------------------ 120 121* ... 122 123Changes to the RISC-V Backend 124----------------------------- 125 126* The Zvfh extension was added. 127 128Changes to the WebAssembly Backend 129---------------------------------- 130 131* ... 132 133Changes to the X86 Backend 134-------------------------- 135 136* ... 137 138Changes to the OCaml bindings 139----------------------------- 140 141 142Changes to the C API 143-------------------- 144 145* Add ``LLVMGetCastOpcode`` function to aid users of ``LLVMBuildCast`` in 146 resolving the best cast operation given a source value and destination type. 147 This function is a direct wrapper of ``CastInst::getCastOpcode``. 148 149Changes to the Go bindings 150-------------------------- 151 152 153Changes to the FastISel infrastructure 154-------------------------------------- 155 156* ... 157 158Changes to the DAG infrastructure 159--------------------------------- 160 161 162Changes to the Debug Info 163--------------------------------- 164 165During this release ... 166 167Changes to the LLVM tools 168--------------------------------- 169 170Changes to LLDB 171--------------------------------- 172 173Changes to Sanitizers 174--------------------- 175 176 177Other Changes 178------------- 179* The code for the `LLVM Visual Studio integration 180 <https://marketplace.visualstudio.com/items?itemName=LLVMExtensions.llvm-toolchain>`_ 181 has been removed. This had been obsolete and abandoned since Visual Studio 182 started including an integration by default in 2019. 183 184External Open Source Projects Using LLVM 15 185=========================================== 186 187* A project... 188 189Additional Information 190====================== 191 192A wide variety of additional information is available on the `LLVM web page 193<https://llvm.org/>`_, in particular in the `documentation 194<https://llvm.org/docs/>`_ section. The web page also contains versions of the 195API documentation which is up-to-date with the Git version of the source 196code. You can access versions of these documents specific to this release by 197going into the ``llvm/docs/`` directory in the LLVM tree. 198 199If you have any questions or comments about LLVM, please feel free to contact 200us via the `mailing lists <https://llvm.org/docs/#mailing-lists>`_. 201