docs/ReleaseNotes.rst - llvm - Git at Google

 ======================
 LLVM 3.8 Release Notes
 ======================

 .. contents::
     :local:


 Introduction
 ============

 This document contains the release notes for the LLVM Compiler Infrastructure,
 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.llvm.org/mailman/listinfo/llvm-dev>`_ is a good place to send
 them.

 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.

 * 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>`_

 * We have documented our C API stability guarantees for both development and
   release branches, as well as documented how to extend the C API. Please see
   the `developer documentation <DeveloperPolicy.html#c-api-changes>`_ for more
   information.

 * 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.

 * 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 deprecated C APIs ``LLVMGetBitcodeModuleProviderInContext`` and
   ``LLVMGetBitcodeModuleProvider`` have been removed.

 * The deprecated C APIs ``LLVMCreateExecutionEngine``, ``LLVMCreateInterpreter``,
   ``LLVMCreateJITCompiler``, ``LLVMAddModuleProvider`` and ``LLVMRemoveModuleProvider``
   have been removed.

 * 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.

 * llvm-ar now supports thin archives.

 * llvm doesn't produce ``.data.rel.ro.local`` or ``.data.rel`` sections anymore.

 * Aliases to ``available_externally`` globals are now rejected by the verifier.

 * The IR Linker has been split into ``IRMover`` that moves bits from one module to
   another and Linker proper that decides what to link.

 * Support for dematerializing has been dropped.

 * ``RegisterScheduler::setDefault`` was removed. Targets that used to call into the
   command line parser to set the ``DAGScheduler``, and that don't have enough
   control with ``setSchedulingPreference``, should look into overriding the
   ``SubTargetHook`` "``getDAGScheduler()``".

 * ``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.

 * ``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 sentinel 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.

 * The `Kaleidoscope tutorials <tutorial/index.html>`_ have been updated to use
   the ORC JIT APIs.

 * ORC now has a basic set of C bindings.

 * Optional support for linking clang and the LLVM tools with a single libLLVM
   shared library. To enable this, pass ``-DLLVM_LINK_LLVM_DYLIB=ON`` to CMake.
   See `Building LLVM with CMake`_ for more details.

 * The optimization to move the prologue and epilogue of functions in colder
   code path (shrink-wrapping) is now enabled by default.

 * A new target-independent gcc-compatible emulated Thread Local Storage mode
   is added.  When ``-femultated-tls`` flag is used, all accesses to TLS
   variables are converted to calls to ``__emutls_get_address`` in the runtime
   library.

 * MSVC-compatible exception handling has been completely overhauled. New
   instructions have been introduced to facilitate this:
   `New exception handling instructions <ExceptionHandling.html#new-exception-handling-instructions>`_.
   While we have done our best to test this feature thoroughly, it would
   not be completely surprising if there were a few lingering issues that
   early adopters might bump into.


 Changes to the ARM Backends
 ---------------------------

 During this release the AArch64 target has:

 * Added support for more sanitizers (MSAN, TSAN) and made them compatible with
   all VMA kernel configurations (currently tested on 39 and 42 bits).
 * Gained initial LLD support in the new ELF back-end
 * Extended the Load/Store optimiser and cleaned up some of the bad decisions
   made earlier.
 * Expanded LLDB support, including watchpoints, native building, Renderscript,
   LLDB-server, debugging 32-bit applications.
 * Added support for the ``Exynos M1`` chip.

 During this release the ARM target has:

 * Gained massive performance improvements on embedded benchmarks due to finally
   running the stride vectorizer in full form, incrementing the performance gains
   that we already had in the previous releases with limited stride vectorization.
 * Expanded LLDB support, including watchpoints, unwind tables
 * Extended the Load/Store optimiser and cleaned up some of the bad decisions
   made earlier.
 * Simplified code generation for global variable addresses in ELF, resulting in
   a significant (4% in Chromium) reduction in code size.
 * Gained some additional code size improvements, though there's still a long road
   ahead, especially for older cores.
 * Added some EABI floating point comparison functions to Compiler-RT
 * Added support for Windows+GNU triple, ``+features`` in ``-mcpu``/``-march`` options.


 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/.

 * 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.

 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
 -----------------------------

 There are numerous improvements to the PowerPC target in this release:

 * Shrink wrapping optimization has been enabled for PowerPC Little Endian

 * Direct move instructions are used when converting scalars to vectors

 * Thread Sanitizer (TSAN) is now supported for PowerPC

 * New MI peephole pass to clean up redundant XXPERMDI instructions

 * Add branch hints to highly biased branch instructions (code reaching
   unreachable terminators and exceptional control flow constructs)

 * Promote boolean return values to integer to prevent excessive usage of
   condition registers

 * Additional vector APIs for vector comparisons and vector merges have been
   added to altivec.h

 * Many bugs have been identified and fixed


 Changes to the X86 Target
 -----------------------------

 * TLS is enabled for Cygwin as emutls.

 * Smaller code for materializing 32-bit 1 and -1 constants at ``-Os``.

 * More efficient code for wide integer compares. (E.g. 64-bit compares
   on 32-bit targets.)

 * Tail call support for ``thiscall``, ``stdcall``, ``vectorcall``, and
   ``fastcall`` functions.

 Changes to the Hexagon Target
 -----------------------------

 In addition to general code size and performance improvements, Hexagon target
 now has basic support for Hexagon V60 architecture and Hexagon Vector
 Extensions (HVX).

 Changes to the AVR Target
 -------------------------

 Slightly less than half of the AVR backend has been merged in at this point. It is still
 missing a number large parts which cause it to be unusable, but is well on the
 road to being completely merged and workable.

 Changes to the OCaml bindings
 -----------------------------

 * 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 3.8.

 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
 ======================

 A wide variety of additional information is available on the `LLVM web page
 <http://llvm.org/>`_, in particular in the `documentation
 <http://llvm.org/docs/>`_ 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 <http://llvm.org/docs/#maillist>`_.
	======================
	LLVM 3.8 Release Notes
	======================

	.. contents::
	:local:


	Introduction
	============

	This document contains the release notes for the LLVM Compiler Infrastructure,
	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.llvm.org/mailman/listinfo/llvm-dev>`_ is a good place to send
	them.

	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.

	* 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>`_

	* We have documented our C API stability guarantees for both development and
	release branches, as well as documented how to extend the C API. Please see
	the `developer documentation <DeveloperPolicy.html#c-api-changes>`_ for more
	information.

	* 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.

	* 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 deprecated C APIs ``LLVMGetBitcodeModuleProviderInContext`` and
	``LLVMGetBitcodeModuleProvider`` have been removed.

	* The deprecated C APIs ``LLVMCreateExecutionEngine``, ``LLVMCreateInterpreter``,
	``LLVMCreateJITCompiler``, ``LLVMAddModuleProvider`` and ``LLVMRemoveModuleProvider``
	have been removed.

	* 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.

	* llvm-ar now supports thin archives.

	* llvm doesn't produce ``.data.rel.ro.local`` or ``.data.rel`` sections anymore.

	* Aliases to ``available_externally`` globals are now rejected by the verifier.

	* The IR Linker has been split into ``IRMover`` that moves bits from one module to
	another and Linker proper that decides what to link.

	* Support for dematerializing has been dropped.

	* ``RegisterScheduler::setDefault`` was removed. Targets that used to call into the
	command line parser to set the ``DAGScheduler``, and that don't have enough
	control with ``setSchedulingPreference``, should look into overriding the
	``SubTargetHook`` "``getDAGScheduler()``".

	* ``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.

	* ``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 sentinel 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.

	* The `Kaleidoscope tutorials <tutorial/index.html>`_ have been updated to use
	the ORC JIT APIs.

	* ORC now has a basic set of C bindings.

	* Optional support for linking clang and the LLVM tools with a single libLLVM
	shared library. To enable this, pass ``-DLLVM_LINK_LLVM_DYLIB=ON`` to CMake.
	See `Building LLVM with CMake`_ for more details.

	* The optimization to move the prologue and epilogue of functions in colder
	code path (shrink-wrapping) is now enabled by default.

	* A new target-independent gcc-compatible emulated Thread Local Storage mode
	is added. When ``-femultated-tls`` flag is used, all accesses to TLS
	variables are converted to calls to ``__emutls_get_address`` in the runtime
	library.

	* MSVC-compatible exception handling has been completely overhauled. New
	instructions have been introduced to facilitate this:
	`New exception handling instructions <ExceptionHandling.html#new-exception-handling-instructions>`_.
	While we have done our best to test this feature thoroughly, it would
	not be completely surprising if there were a few lingering issues that
	early adopters might bump into.


	Changes to the ARM Backends
	---------------------------

	During this release the AArch64 target has:

	* Added support for more sanitizers (MSAN, TSAN) and made them compatible with
	all VMA kernel configurations (currently tested on 39 and 42 bits).
	* Gained initial LLD support in the new ELF back-end
	* Extended the Load/Store optimiser and cleaned up some of the bad decisions
	made earlier.
	* Expanded LLDB support, including watchpoints, native building, Renderscript,
	LLDB-server, debugging 32-bit applications.
	* Added support for the ``Exynos M1`` chip.

	During this release the ARM target has:

	* Gained massive performance improvements on embedded benchmarks due to finally
	running the stride vectorizer in full form, incrementing the performance gains
	that we already had in the previous releases with limited stride vectorization.
	* Expanded LLDB support, including watchpoints, unwind tables
	* Extended the Load/Store optimiser and cleaned up some of the bad decisions
	made earlier.
	* Simplified code generation for global variable addresses in ELF, resulting in
	a significant (4% in Chromium) reduction in code size.
	* Gained some additional code size improvements, though there's still a long road
	ahead, especially for older cores.
	* Added some EABI floating point comparison functions to Compiler-RT
	* Added support for Windows+GNU triple, ``+features`` in ``-mcpu``/``-march`` options.


	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/.

	* 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.

	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
	-----------------------------

	There are numerous improvements to the PowerPC target in this release:

	* Shrink wrapping optimization has been enabled for PowerPC Little Endian

	* Direct move instructions are used when converting scalars to vectors

	* Thread Sanitizer (TSAN) is now supported for PowerPC

	* New MI peephole pass to clean up redundant XXPERMDI instructions

	* Add branch hints to highly biased branch instructions (code reaching
	unreachable terminators and exceptional control flow constructs)

	* Promote boolean return values to integer to prevent excessive usage of
	condition registers

	* Additional vector APIs for vector comparisons and vector merges have been
	added to altivec.h

	* Many bugs have been identified and fixed


	Changes to the X86 Target
	-----------------------------

	* TLS is enabled for Cygwin as emutls.

	* Smaller code for materializing 32-bit 1 and -1 constants at ``-Os``.

	* More efficient code for wide integer compares. (E.g. 64-bit compares
	on 32-bit targets.)

	* Tail call support for ``thiscall``, ``stdcall``, ``vectorcall``, and
	``fastcall`` functions.

	Changes to the Hexagon Target
	-----------------------------

	In addition to general code size and performance improvements, Hexagon target
	now has basic support for Hexagon V60 architecture and Hexagon Vector
	Extensions (HVX).

	Changes to the AVR Target
	-------------------------

	Slightly less than half of the AVR backend has been merged in at this point. It is still
	missing a number large parts which cause it to be unusable, but is well on the
	road to being completely merged and workable.

	Changes to the OCaml bindings
	-----------------------------

	* 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 3.8.

	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
	======================

	A wide variety of additional information is available on the `LLVM web page
	<http://llvm.org/>`_, in particular in the `documentation
	<http://llvm.org/docs/>`_ 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 <http://llvm.org/docs/#maillist>`_.