======================
-LLVM 3.4 Release Notes
+LLVM 3.8 Release Notes
======================
.. contents::
:local:
.. warning::
- These are in-progress notes for the upcoming LLVM 3.4 release. You may
- prefer the `LLVM 3.3 Release Notes <http://llvm.org/releases/3.3/docs
+ These are in-progress notes for the upcoming LLVM 3.8 release. You may
+ prefer the `LLVM 3.7 Release Notes <http://llvm.org/releases/3.7.0/docs
/ReleaseNotes.html>`_.
============
This document contains the release notes for the LLVM Compiler Infrastructure,
-release 3.4. Here we describe the status of LLVM, including major improvements
+release 3.8. 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 <http://llvm.org/releases/>`_.
For more information about LLVM, including information about the latest
release, please check out the `main LLVM web site <http://llvm.org/>`_. If you
have questions or comments, the `LLVM Developer's Mailing List
-<http://lists.cs.uiuc.edu/mailman/listinfo/llvmdev>`_ is a good place to send
+<http://lists.llvm.org/mailman/listinfo/llvm-dev>`_ is a good place to send
them.
Note that if you are reading this file from a Subversion checkout or the main
Non-comprehensive list of changes in this release
=================================================
+* With this release, the minimum Windows version required for running LLVM is
+ Windows 7. Earlier versions, including Windows Vista and XP are no longer
+ supported.
-.. 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.
+* With this release, the autoconf build system is deprecated. It will be removed
+ in the 3.9 release. Please migrate to using CMake. For more information see:
+ `Building LLVM with CMake <CMake.html>`_
+
+* The C API function LLVMLinkModules is deprecated. It will be removed in the
+ 3.9 release. Please migrate to LLVMLinkModules2. Unlike the old function the
+ new one
+
+ * Doesn't take an unused parameter.
+ * Destroys the source instead of only damaging it.
+ * Does not record a message. Use the diagnostic handler instead.
-* This is expected to be the last release of LLVM which compiles using a C++98
- toolchain. We expect to start using some C++11 features in LLVM and other
- sub-projects starting after this release. That said, we are committed to
- supporting a reasonable set of modern C++ toolchains as the host compiler on
- all of the platforms. This will at least include Visual Studio 2012 on
- Windows, and Clang 3.1 or GCC 4.7.x on Mac and Linux. The final set of
- compilers (and the C++11 features they support) is not set in stone, but we
- wanted users of LLVM to have a heads up that the next release will involve
- a substantial change in the host toolchain requirements.
+* The C API functions LLVMParseBitcode, LLVMParseBitcodeInContext,
+ LLVMGetBitcodeModuleInContext and LLVMGetBitcodeModule have been deprecated.
+ They will be removed in 3.9. Please migrate to the versions with a 2 suffix.
+ Unlike the old ones the new ones do not record a diagnostic message. Use
+ the diagnostic handler instead.
-* The regression tests now fail if any command in a pipe fails. To disable it in
- a directory, just add ``config.pipefail = False`` to its ``lit.local.cfg``.
- See :doc:`Lit <CommandGuide/lit>` for the details.
+* The deprecated C APIs LLVMGetBitcodeModuleProviderInContext and
+ LLVMGetBitcodeModuleProvider have been removed.
-* Support for exception handling has been removed from the old JIT. Use MCJIT
- if you need EH support.
+* The deprecated C APIs LLVMCreateExecutionEngine, LLVMCreateInterpreter,
+ LLVMCreateJITCompiler, LLVMAddModuleProvider and LLVMRemoveModuleProvider
+ have been removed.
-* The R600 backend is not marked experimental anymore and is built by default.
+* With this release, the C API headers have been reorganized to improve build
+ time. Type specific declarations have been moved to Type.h, and error
+ handling routines have been moved to ErrorHandling.h. Both are included in
+ Core.h so nothing should change for projects directly including the headers,
+ but transitive dependencies may be affected.
-* APFloat::isNormal() was renamed to APFloat::isFiniteNonZero() and
- APFloat::isIEEENormal() was renamed to APFloat::isNormal(). This ensures that
- APFloat::isNormal() conforms to IEEE-754R-2008.
+* llvm-ar now suports thin archives.
-* The library call simplification pass has been removed. Its functionality
- has been integrated into the instruction combiner and function attribute
- marking passes.
+* llvm doesn't produce .data.rel.ro.local or .data.rel sections anymore.
-* Support for building using Visual Studio 2008 has been dropped. Use VS 2010
- or later instead. For more information, see the `Getting Started using Visual
- Studio <GettingStartedVS.html>`_ page.
+* aliases to available_externally globals are now rejected by the verifier.
-* The Loop Vectorizer that was previously enabled for -O3 is now enabled for
- -Os and -O2.
+* the IR Linker has been split into IRMover that moves bits from one module to
+ another and Linker proper that decides what to link.
-* The new SLP Vectorizer is now enabled by default.
+* Support for dematerializing has been dropped.
-* llvm-ar now uses the new Object library and produces archives and
- symbol tables in the gnu format.
+* ``ilist_iterator<T>`` no longer has implicit conversions to and from ``T*``,
+ since ``ilist_iterator<T>`` may be pointing at the sentinel (which is usually
+ not of type ``T`` at all). To convert from an iterator ``I`` to a pointer,
+ use ``&*I``; to convert from a pointer ``P`` to an iterator, use
+ ``P->getIterator()``. Alternatively, explicit conversions via
+ ``static_cast<T>(U)`` are still available.
-* FileCheck now allows specifing -check-prefix multiple times. This
- helps reduce duplicate check lines when using multiple RUN lines.
+* ``ilist_node<T>::getNextNode()`` and ``ilist_node<T>::getPrevNode()`` now
+ fail at compile time when the node cannot access its parent list.
+ Previously, when the sentinel was was an ``ilist_half_node<T>``, this API
+ could return the sentinal instead of ``nullptr``. Frustrated callers should
+ be updated to use ``iplist<T>::getNextNode(T*)`` instead. Alternatively, if
+ the node ``N`` is guaranteed not to be the last in the list, it is safe to
+ call ``&*++N->getIterator()`` directly.
+
+.. 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.
* ... next change ...
Makes programs 10x faster by doing Special New Thing.
+Changes to the ARM Backend
+--------------------------
+
+ During this release ...
+
+
+Changes to the MIPS Target
+--------------------------
+
+During this release the MIPS target has:
+
+* Significantly extended support for the Integrated Assembler. See below for
+ more information
+* Added support for the ``P5600`` processor.
+* Added support for the ``interrupt`` attribute for MIPS32R2 and later. This
+ attribute will generate a function which can be used as a interrupt handler
+ on bare metal MIPS targets using the static relocation model.
+* Added support for the ``ERETNC`` instruction found in MIPS32R5 and later.
+* Added support for OpenCL. See http://portablecl.org/.
-External Open Source Projects Using LLVM 3.4
+ * Address spaces 1 to 255 are now reserved for software use and conversions
+ between them are no-op casts.
+
+* Removed the ``mips16`` value for the -mcpu option since it is an :abbr:`ASE
+ (Application Specific Extension)` and not a processor. If you were using this,
+ please specify another CPU and use ``-mips16`` to enable MIPS16.
+* Removed ``copy_u.w`` from 32-bit MSA and ``copy_u.d`` from 64-bit MSA since
+ they have been removed from the MSA specification due to forward compatibility
+ issues. For example, 32-bit MSA code containing ``copy_u.w`` would behave
+ differently on a 64-bit processor supporting MSA. The corresponding intrinsics
+ are still available and may expand to ``copy_s.[wd]`` where this is
+ appropriate for forward compatibility purposes.
+* Relaxed the ``-mnan`` option to allow ``-mnan=2008`` on MIPS32R2/MIPS64R2 for
+ compatibility with GCC.
+* Made MIPS64R6 the default CPU for 64-bit Android triples.
+
+The MIPS target has also fixed various bugs including the following notable
+fixes:
+
+* Fixed reversed operands on ``mthi``/``mtlo`` in the DSP :abbr:`ASE
+ (Application Specific Extension)`.
+* The code generator no longer uses ``jal`` for calls to absolute immediate
+ addresses.
+* Disabled fast instruction selection on MIPS32R6 and MIPS64R6 since this is not
+ yet supported.
+* Corrected addend for ``R_MIPS_HI16`` and ``R_MIPS_PCHI16`` in MCJIT
+* The code generator no longer crashes when handling subregisters of an 64-bit
+ FPU register with undefined value.
+* The code generator no longer attempts to use ``$zero`` for operands that do
+ not permit ``$zero``.
+* Corrected the opcode used for ``ll``/``sc`` when using MIPS32R6/MIPS64R6 and
+ the Integrated Assembler.
+* Added support for atomic load and atomic store.
+* Corrected debug info when dynamically re-aligning the stack.
+
+Integrated Assembler
+^^^^^^^^^^^^^^^^^^^^
+We have made a large number of improvements to the integrated assembler for
+MIPS. In this release, the integrated assembler isn't quite production-ready
+since there are a few known issues related to bare-metal support, checking
+immediates on instructions, and the N32/N64 ABI's. However, the current support
+should be sufficient for many users of the O32 ABI, particularly those targeting
+MIPS32 on Linux or bare-metal MIPS32.
+
+If you would like to try the integrated assembler, please use
+``-fintegrated-as``.
+
+Changes to the PowerPC Target
+-----------------------------
+
+ During this release ...
+
+
+Changes to the X86 Target
+-----------------------------
+
+ During this release ...
+
+* TLS is enabled for Cygwin as emutls.
+
+
+Changes to the OCaml bindings
+-----------------------------
+
+ During this release ...
+
+* The ocaml function link_modules has been replaced with link_modules' which
+ uses LLVMLinkModules2.
+
+
+External Open Source Projects Using LLVM 3.8
============================================
An exciting aspect of LLVM is that it is used as an enabling technology for
a lot of other language and tools projects. This section lists some of the
-projects that have already been updated to work with LLVM 3.4.
+projects that have already been updated to work with LLVM 3.8.
+
+LDC - the LLVM-based D compiler
+-------------------------------
+
+`D <http://dlang.org>`_ is a language with C-like syntax and static typing. It
+pragmatically combines efficiency, control, and modeling power, with safety and
+programmer productivity. D supports powerful concepts like Compile-Time Function
+Execution (CTFE) and Template Meta-Programming, provides an innovative approach
+to concurrency and offers many classical paradigms.
+
+`LDC <http://wiki.dlang.org/LDC>`_ uses the frontend from the reference compiler
+combined with LLVM as backend to produce efficient native code. LDC targets
+x86/x86_64 systems like Linux, OS X and Windows and also PowerPC (32/64 bit)
+and ARM. Ports to other architectures like AArch64 and MIPS64 are underway.
Additional Information
projects / oota-llvm.git / blobdiff