We use here the command-line, non-interactive CMake interface.
#. `Download <http://www.cmake.org/cmake/resources/software.html>`_ and install
- CMake. Version 2.8 is the minimum required.
+ CMake. Version 2.8.8 is the minimum required.
#. Open a shell. Your development tools must be reachable from this shell
through the PATH environment variable.
environment variable, for instance. You can force CMake to use a given build
tool, see the `Usage`_ section.
+#. After CMake has finished running, proceed to use IDE project files or start
+ the build from the build directory:
+
+ .. code-block:: console
+
+ $ cmake --build .
+
+ The ``--build`` option tells ``cmake`` to invoke the underlying build
+ tool (``make``, ``ninja``, ``xcodebuild``, ``msbuild``, etc).
+
+ The underlying build tool can be invoked directly either of course, but
+ the ``--build`` option is portable.
+
+#. After LLVM has finished building, install it from the build directory:
+
+ .. code-block:: console
+
+ $ cmake --build . --target install
+
+ The ``--target`` option with ``install`` parameter in addition to
+ the ``--build`` option tells ``cmake`` to build the ``install`` target.
+
+ It is possible to set a different install prefix at installation time
+ by invoking the ``cmake_install.cmake`` script generated in the
+ build directory:
+
+ .. code-block:: console
+
+ $ cmake -DCMAKE_INSTALL_PREFIX=/tmp/llvm -P cmake_install.cmake
+
.. _Basic CMake usage:
.. _Usage:
Build in C++1y mode, if available. Defaults to OFF.
**LLVM_ENABLE_ASSERTIONS**:BOOL
- Enables code assertions. Defaults to OFF if and only if ``CMAKE_BUILD_TYPE``
- is *Release*.
+ Enables code assertions. Defaults to ON if and only if ``CMAKE_BUILD_TYPE``
+ is *Debug*.
+
+**LLVM_ENABLE_EH**:BOOL
+ Build LLVM with exception handling support. This is necessary if you wish to
+ link against LLVM libraries and make use of C++ exceptions in your own code
+ that need to propagate through LLVM code. Defaults to OFF.
**LLVM_ENABLE_PIC**:BOOL
Add the ``-fPIC`` flag for the compiler command-line, if the compiler supports
this flag. Some systems, like Windows, do not need this flag. Defaults to ON.
+**LLVM_ENABLE_RTTI**:BOOL
+ Build LLVM with run time type information. Defaults to OFF.
+
**LLVM_ENABLE_WARNINGS**:BOOL
Enable all compiler warnings. Defaults to ON.
**LLVM_ENABLE_PEDANTIC**:BOOL
- Enable pedantic mode. This disable compiler specific extensions, is
+ Enable pedantic mode. This disables compiler specific extensions, if
possible. Defaults to ON.
**LLVM_ENABLE_WERROR**:BOOL
Stop and fail build, if a compiler warning is triggered. Defaults to OFF.
+**LLVM_ABI_BREAKING_CHECKS**:STRING
+ Used to decide if LLVM should be built with ABI breaking checks or
+ not. Allowed values are `WITH_ASSERTS` (default), `FORCE_ON` and
+ `FORCE_OFF`. `WITH_ASSERTS` turns on ABI breaking checks in an
+ assertion enabled build. `FORCE_ON` (`FORCE_OFF`) turns them on
+ (off) irrespective of whether normal (`NDEBUG` based) assertions are
+ enabled or not. A version of LLVM built with ABI breaking checks
+ is not ABI compatible with a version built without it.
+
**LLVM_BUILD_32_BITS**:BOOL
Build 32-bits executables and libraries on 64-bits systems. This option is
available only on some 64-bits unix systems. Defaults to OFF.
**LLVM_USE_SANITIZER**:STRING
Define the sanitizer used to build LLVM binaries and tests. Possible values
- are ``Address``, ``Memory`` and ``MemoryWithOrigins``. Defaults to empty
- string.
+ are ``Address``, ``Memory``, ``MemoryWithOrigins``, ``Undefined``, ``Thread``,
+ and ``Address;Undefined``. Defaults to empty string.
+
+**LLVM_PARALLEL_COMPILE_JOBS**:STRING
+ Define the maximum number of concurrent compilation jobs.
+
+**LLVM_PARALLEL_LINK_JOBS**:STRING
+ Define the maximum number of concurrent link jobs.
**LLVM_BUILD_DOCS**:BOOL
Enables all enabled documentation targets (i.e. Doxgyen and Sphinx targets) to
otherwise this has no effect.
**LLVM_DOXYGEN_QCH_FILENAME**:STRING
- The filename of the Qt Compressed Help file that will be genrated when
- ``-DLLVM_ENABLE_DOXYGEN=ON`` and
+ The filename of the Qt Compressed Help file that will be generated when
+ ``-DLLVM_ENABLE_DOXYGEN=ON`` and
``-DLLVM_ENABLE_DOXYGEN_QT_HELP=ON`` are given. Defaults to
``org.llvm.qch``.
This option is only useful in combination with
for more information. Defaults to "org.llvm". This option is only useful in
combination with ``-DLLVM_ENABLE_DOXYGEN_QT_HELP=ON``; otherwise
this has no effect.
-
+
**LLVM_DOXYGEN_QHP_CUST_FILTER_NAME**:STRING
See `Qt Help Project`_ for
more information. Defaults to the CMake variable ``${PACKAGE_STRING}`` which
is enabled). Currently the only target added is ``docs-llvm-man``. Defaults
to ON.
+**SPHINX_WARNINGS_AS_ERRORS**:BOOL
+ If enabled then sphinx documentation warnings will be treated as
+ errors. Defaults to ON.
+
Executing the test suite
========================
Embedding LLVM in your project
==============================
-The most difficult part of adding LLVM to the build of a project is to determine
-the set of LLVM libraries corresponding to the set of required LLVM
-features. What follows is an example of how to obtain this information:
+From LLVM 3.5 onwards both the CMake and autoconf/Makefile build systems export
+LLVM libraries as importable CMake targets. This means that clients of LLVM can
+now reliably use CMake to develop their own LLVM based projects against an
+installed version of LLVM regardless of how it was built.
+
+Here is a simple example of CMakeLists.txt file that imports the LLVM libraries
+and uses them to build a simple application ``simple-tool``.
.. code-block:: cmake
- # A convenience variable:
- set(LLVM_ROOT "" CACHE PATH "Root of LLVM install.")
+ cmake_minimum_required(VERSION 2.8.8)
+ project(SimpleProject)
- # A bit of a sanity check:
- if( NOT EXISTS ${LLVM_ROOT}/include/llvm )
- message(FATAL_ERROR "LLVM_ROOT (${LLVM_ROOT}) is not a valid LLVM install")
- endif()
+ find_package(LLVM REQUIRED CONFIG)
- # We incorporate the CMake features provided by LLVM:
- set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${LLVM_ROOT}/share/llvm/cmake")
- include(LLVMConfig)
+ message(STATUS "Found LLVM ${LLVM_PACKAGE_VERSION}")
+ message(STATUS "Using LLVMConfig.cmake in: ${LLVM_DIR}")
- # Now set the header and library paths:
- include_directories( ${LLVM_INCLUDE_DIRS} )
- link_directories( ${LLVM_LIBRARY_DIRS} )
- add_definitions( ${LLVM_DEFINITIONS} )
+ # Set your project compile flags.
+ # E.g. if using the C++ header files
+ # you will need to enable C++11 support
+ # for your compiler.
- # Let's suppose we want to build a JIT compiler with support for
- # binary code (no interpreter):
- llvm_map_components_to_libraries(REQ_LLVM_LIBRARIES jit native)
+ include_directories(${LLVM_INCLUDE_DIRS})
+ add_definitions(${LLVM_DEFINITIONS})
- # Finally, we link the LLVM libraries to our executable:
- target_link_libraries(mycompiler ${REQ_LLVM_LIBRARIES})
+ # Now build our tools
+ add_executable(simple-tool tool.cpp)
-This assumes that LLVM_ROOT points to an install of LLVM. The procedure works
-too for uninstalled builds although we need to take care to add an
-`include_directories` for the location of the headers on the LLVM source
-directory (if we are building out-of-source.)
+ # Find the libraries that correspond to the LLVM components
+ # that we wish to use
+ llvm_map_components_to_libnames(llvm_libs support core irreader)
-Alternativaly, you can utilize CMake's ``find_package`` functionality. Here is
-an equivalent variant of snippet shown above:
+ # Link against LLVM libraries
+ target_link_libraries(simple-tool ${llvm_libs})
-.. code-block:: cmake
+The ``find_package(...)`` directive when used in CONFIG mode (as in the above
+example) will look for the ``LLVMConfig.cmake`` file in various locations (see
+cmake manual for details). It creates a ``LLVM_DIR`` cache entry to save the
+directory where ``LLVMConfig.cmake`` is found or allows the user to specify the
+directory (e.g. by passing ``-DLLVM_DIR=/usr/share/llvm/cmake`` to
+the ``cmake`` command or by setting it directly in ``ccmake`` or ``cmake-gui``).
+
+This file is available in two different locations.
+
+* ``<INSTALL_PREFIX>/share/llvm/cmake/LLVMConfig.cmake`` where
+ ``<INSTALL_PREFIX>`` is the install prefix of an installed version of LLVM.
+ On Linux typically this is ``/usr/share/llvm/cmake/LLVMConfig.cmake``.
+
+* ``<LLVM_BUILD_ROOT>/share/llvm/cmake/LLVMConfig.cmake`` where
+ ``<LLVM_BUILD_ROOT>`` is the root of the LLVM build tree. **Note this only
+ available when building LLVM with CMake**
+
+If LLVM is installed in your operating system's normal installation prefix (e.g.
+on Linux this is usually ``/usr/``) ``find_package(LLVM ...)`` will
+automatically find LLVM if it is installed correctly. If LLVM is not installed
+or you wish to build directly against the LLVM build tree you can use
+``LLVM_DIR`` as previously mentioned.
+
+The ``LLVMConfig.cmake`` file sets various useful variables. Notable variables
+include
- find_package(LLVM)
+``LLVM_CMAKE_DIR``
+ The path to the LLVM CMake directory (i.e. the directory containing
+ LLVMConfig.cmake).
- if( NOT LLVM_FOUND )
- message(FATAL_ERROR "LLVM package can't be found. Set CMAKE_PREFIX_PATH variable to LLVM's installation prefix.")
- endif()
+``LLVM_DEFINITIONS``
+ A list of preprocessor defines that should be used when building against LLVM.
- include_directories( ${LLVM_INCLUDE_DIRS} )
- link_directories( ${LLVM_LIBRARY_DIRS} )
+``LLVM_ENABLE_ASSERTIONS``
+ This is set to ON if LLVM was built with assertions, otherwise OFF.
- llvm_map_components_to_libraries(REQ_LLVM_LIBRARIES jit native)
+``LLVM_ENABLE_EH``
+ This is set to ON if LLVM was built with exception handling (EH) enabled,
+ otherwise OFF.
- target_link_libraries(mycompiler ${REQ_LLVM_LIBRARIES})
+``LLVM_ENABLE_RTTI``
+ This is set to ON if LLVM was built with run time type information (RTTI),
+ otherwise OFF.
+
+``LLVM_INCLUDE_DIRS``
+ A list of include paths to directories containing LLVM header files.
+
+``LLVM_PACKAGE_VERSION``
+ The LLVM version. This string can be used with CMake conditionals. E.g. ``if
+ (${LLVM_PACKAGE_VERSION} VERSION_LESS "3.5")``.
+
+``LLVM_TOOLS_BINARY_DIR``
+ The path to the directory containing the LLVM tools (e.g. ``llvm-as``).
+
+Notice that in the above example we link ``simple-tool`` against several LLVM
+libraries. The list of libraries is determined by using the
+``llvm_map_components_to_libnames()`` CMake function. For a list of available
+components look at the output of running ``llvm-config --components``.
+
+Note that for LLVM < 3.5 ``llvm_map_components_to_libraries()`` was
+used instead of ``llvm_map_components_to_libnames()``. This is now deprecated
+and will be removed in a future version of LLVM.
.. _cmake-out-of-source-pass:
-Developing LLVM pass out of source
-----------------------------------
+Developing LLVM passes out of source
+------------------------------------
-It is possible to develop LLVM passes against installed LLVM. An example of
-project layout provided below:
+It is possible to develop LLVM passes out of LLVM's source tree (i.e. against an
+installed or built LLVM). An example of a project layout is provided below.
.. code-block:: none
.. code-block:: cmake
- find_package(LLVM)
-
- # Define add_llvm_* macro's.
- include(AddLLVM)
+ find_package(LLVM REQUIRED CONFIG)
add_definitions(${LLVM_DEFINITIONS})
include_directories(${LLVM_INCLUDE_DIRS})
- link_directories(${LLVM_LIBRARY_DIRS})
add_subdirectory(<pass name>)
Contents of ``<project dir>/<pass name>/CMakeLists.txt``:
+.. code-block:: cmake
+
+ add_library(LLVMPassname MODULE Pass.cpp)
+
+Note if you intend for this pass to be merged into the LLVM source tree at some
+point in the future it might make more sense to use LLVM's internal
+add_llvm_loadable_module function instead by...
+
+
+Adding the following to ``<project dir>/CMakeLists.txt`` (after
+``find_package(LLVM ...)``)
+
+.. code-block:: cmake
+
+ list(APPEND CMAKE_MODULE_PATH "${LLVM_CMAKE_DIR}")
+ include(AddLLVM)
+
+And then changing ``<project dir>/<pass name>/CMakeLists.txt`` to
+
.. code-block:: cmake
add_llvm_loadable_module(LLVMPassname
#. Adding ``add_subdirectory(<pass name>)`` line into
``<LLVM root>/lib/Transform/CMakeLists.txt``.
-Compiler/Platform specific topics
+Compiler/Platform-specific topics
=================================
Notes for specific compilers and/or platforms.
projects / oota-llvm.git / blobdiff