======================== LLVM 4.0.0 Release Notes ======================== .. contents:: :local: .. warning:: These are in-progress notes for the upcoming LLVM 4.0.0 release. You may prefer the `LLVM 3.9 Release Notes `_. Introduction ============ This document contains the release notes for the LLVM Compiler Infrastructure, release 4.0.0. 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 ================================================= * The C API functions LLVMAddFunctionAttr, LLVMGetFunctionAttr, LLVMRemoveFunctionAttr, LLVMAddAttribute, LLVMRemoveAttribute, LLVMGetAttribute, LLVMAddInstrAttribute and LLVMRemoveInstrAttribute have been removed. * The C API enum LLVMAttribute has been deleted. .. 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. * The definition and uses of LLVM_ATRIBUTE_UNUSED_RESULT in the LLVM source were replaced with LLVM_NODISCARD, which matches the C++17 [[nodiscard]] semantics rather than gcc's __attribute__((warn_unused_result)). * Minimum compiler version to build has been raised to GCC 4.8 and VS 2015. * The Timer related APIs now expect a Name and Description. When upgrading code the previously used names should become descriptions and a short name in the style of a programming language identifier should be added. * ... next change ... .. NOTE If you would like to document a larger change, then you can add a subsection about it right here. You can copy the following boilerplate and un-indent it (the indentation causes it to be inside this comment). Special New Feature ------------------- Makes programs 10x faster by doing Special New Thing. Changes to the LLVM IR ---------------------- 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 ------------------------- During this release ... Changes to the AMDGPU Target ----------------------------- During this release ... Changes to the AVR Target ----------------------------- * The entire backend has been merged in-tree with all tests passing. All of the instruction selection code and the machine code backend has landed recently and is fully usable. Changes to the OCaml bindings ----------------------------- * The attribute API was completely overhauled, following the changes to the C API. External Open Source Projects Using LLVM 4.0.0 ============================================== * 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 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. If you have any questions or comments about LLVM, please feel free to contact us via the `mailing lists `_.