[llvm] r232135 - Updating GettingStarted documentation to reference CMake as the preferred way to build LLVM.
Chris Bieneman
beanz at apple.com
Thu Mar 12 18:58:14 PDT 2015
Author: cbieneman
Date: Thu Mar 12 20:58:14 2015
New Revision: 232135
URL: http://llvm.org/viewvc/llvm-project?rev=232135&view=rev
Log:
Updating GettingStarted documentation to reference CMake as the preferred way to build LLVM.
Reviewers: chandlerc, samsonov, echristo
Reviewed By: samsonov
Subscribers: emaste, joker.eph, llvm-commits
Differential Revision: http://reviews.llvm.org/D8046
Added:
llvm/trunk/docs/BuildingLLVMWithAutotools.rst
Modified:
llvm/trunk/docs/GettingStarted.rst
llvm/trunk/docs/index.rst
Added: llvm/trunk/docs/BuildingLLVMWithAutotools.rst
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/docs/BuildingLLVMWithAutotools.rst?rev=232135&view=auto
==============================================================================
--- llvm/trunk/docs/BuildingLLVMWithAutotools.rst (added)
+++ llvm/trunk/docs/BuildingLLVMWithAutotools.rst Thu Mar 12 20:58:14 2015
@@ -0,0 +1,297 @@
+====================================
+Building LLVM With Autotools
+====================================
+
+.. contents::
+ :local:
+
+Overview
+========
+
+
+Local LLVM Configuration
+------------------------
+
+Once checked out from the Subversion repository, the LLVM suite source code must
+be configured via the ``configure`` script. This script sets variables in the
+various ``*.in`` files, most notably ``llvm/Makefile.config`` and
+``llvm/include/Config/config.h``. It also populates *OBJ_ROOT* with the
+Makefiles needed to begin building LLVM.
+
+The following environment variables are used by the ``configure`` script to
+configure the build system:
+
++------------+-----------------------------------------------------------+
+| Variable | Purpose |
++============+===========================================================+
+| CC | Tells ``configure`` which C compiler to use. By default, |
+| | ``configure`` will check ``PATH`` for ``clang`` and GCC C |
+| | compilers (in this order). Use this variable to override |
+| | ``configure``\'s default behavior. |
++------------+-----------------------------------------------------------+
+| CXX | Tells ``configure`` which C++ compiler to use. By |
+| | default, ``configure`` will check ``PATH`` for |
+| | ``clang++`` and GCC C++ compilers (in this order). Use |
+| | this variable to override ``configure``'s default |
+| | behavior. |
++------------+-----------------------------------------------------------+
+
+The following options can be used to set or enable LLVM specific options:
+
+``--enable-optimized``
+
+ Enables optimized compilation (debugging symbols are removed and GCC
+ optimization flags are enabled). Note that this is the default setting if you
+ are using the LLVM distribution. The default behavior of a Subversion
+ checkout is to use an unoptimized build (also known as a debug build).
+
+``--enable-debug-runtime``
+
+ Enables debug symbols in the runtime libraries. The default is to strip debug
+ symbols from the runtime libraries.
+
+``--enable-jit``
+
+ Compile the Just In Time (JIT) compiler functionality. This is not available
+ on all platforms. The default is dependent on platform, so it is best to
+ explicitly enable it if you want it.
+
+``--enable-targets=target-option``
+
+ Controls which targets will be built and linked into llc. The default value
+ for ``target_options`` is "all" which builds and links all available targets.
+ The "host" target is selected as the target of the build host. You can also
+ specify a comma separated list of target names that you want available in llc.
+ The target names use all lower case. The current set of targets is:
+
+ ``aarch64, arm, arm64, cpp, hexagon, mips, mipsel, mips64, mips64el, msp430,
+ powerpc, nvptx, r600, sparc, systemz, x86, x86_64, xcore``.
+
+``--enable-doxygen``
+
+ Look for the doxygen program and enable construction of doxygen based
+ documentation from the source code. This is disabled by default because
+ generating the documentation can take a long time and producess 100s of
+ megabytes of output.
+
+To configure LLVM, follow these steps:
+
+#. Change directory into the object root directory:
+
+ .. code-block:: console
+
+ % cd OBJ_ROOT
+
+#. Run the ``configure`` script located in the LLVM source tree:
+
+ .. code-block:: console
+
+ % SRC_ROOT/configure --prefix=/install/path [other options]
+
+Compiling the LLVM Suite Source Code
+------------------------------------
+
+Once you have configured LLVM, you can build it. There are three types of
+builds:
+
+Debug Builds
+
+ These builds are the default when one is using a Subversion checkout and
+ types ``gmake`` (unless the ``--enable-optimized`` option was used during
+ configuration). The build system will compile the tools and libraries with
+ debugging information. To get a Debug Build using the LLVM distribution the
+ ``--disable-optimized`` option must be passed to ``configure``.
+
+Release (Optimized) Builds
+
+ These builds are enabled with the ``--enable-optimized`` option to
+ ``configure`` or by specifying ``ENABLE_OPTIMIZED=1`` on the ``gmake`` command
+ line. For these builds, the build system will compile the tools and libraries
+ with GCC optimizations enabled and strip debugging information from the
+ libraries and executables it generates. Note that Release Builds are default
+ when using an LLVM distribution.
+
+Profile Builds
+
+ These builds are for use with profiling. They compile profiling information
+ into the code for use with programs like ``gprof``. Profile builds must be
+ started by specifying ``ENABLE_PROFILING=1`` on the ``gmake`` command line.
+
+Once you have LLVM configured, you can build it by entering the *OBJ_ROOT*
+directory and issuing the following command:
+
+.. code-block:: console
+
+ % gmake
+
+If the build fails, please `check here <GettingStarted.html#check-here>`_
+to see if you are using a version of GCC that is known not to compile LLVM.
+
+If you have multiple processors in your machine, you may wish to use some of the
+parallel build options provided by GNU Make. For example, you could use the
+command:
+
+.. code-block:: console
+
+ % gmake -j2
+
+There are several special targets which are useful when working with the LLVM
+source code:
+
+``gmake clean``
+
+ Removes all files generated by the build. This includes object files,
+ generated C/C++ files, libraries, and executables.
+
+``gmake dist-clean``
+
+ Removes everything that ``gmake clean`` does, but also removes files generated
+ by ``configure``. It attempts to return the source tree to the original state
+ in which it was shipped.
+
+``gmake install``
+
+ Installs LLVM header files, libraries, tools, and documentation in a hierarchy
+ under ``$PREFIX``, specified with ``./configure --prefix=[dir]``, which
+ defaults to ``/usr/local``.
+
+``gmake -C runtime install-bytecode``
+
+ Assuming you built LLVM into $OBJDIR, when this command is run, it will
+ install bitcode libraries into the GCC front end's bitcode library directory.
+ If you need to update your bitcode libraries, this is the target to use once
+ you've built them.
+
+Please see the `Makefile Guide <MakefileGuide.html>`_ for further details on
+these ``make`` targets and descriptions of other targets available.
+
+It is also possible to override default values from ``configure`` by declaring
+variables on the command line. The following are some examples:
+
+``gmake ENABLE_OPTIMIZED=1``
+
+ Perform a Release (Optimized) build.
+
+``gmake ENABLE_OPTIMIZED=1 DISABLE_ASSERTIONS=1``
+
+ Perform a Release (Optimized) build without assertions enabled.
+
+``gmake ENABLE_OPTIMIZED=0``
+
+ Perform a Debug build.
+
+``gmake ENABLE_PROFILING=1``
+
+ Perform a Profiling build.
+
+``gmake VERBOSE=1``
+
+ Print what ``gmake`` is doing on standard output.
+
+``gmake TOOL_VERBOSE=1``
+
+ Ask each tool invoked by the makefiles to print out what it is doing on
+ the standard output. This also implies ``VERBOSE=1``.
+
+Every directory in the LLVM object tree includes a ``Makefile`` to build it and
+any subdirectories that it contains. Entering any directory inside the LLVM
+object tree and typing ``gmake`` should rebuild anything in or below that
+directory that is out of date.
+
+This does not apply to building the documentation.
+LLVM's (non-Doxygen) documentation is produced with the
+`Sphinx <http://sphinx-doc.org/>`_ documentation generation system.
+There are some HTML documents that have not yet been converted to the new
+system (which uses the easy-to-read and easy-to-write
+`reStructuredText <http://sphinx-doc.org/rest.html>`_ plaintext markup
+language).
+The generated documentation is built in the ``SRC_ROOT/docs`` directory using
+a special makefile.
+For instructions on how to install Sphinx, see
+`Sphinx Introduction for LLVM Developers
+<http://lld.llvm.org/sphinx_intro.html>`_.
+After following the instructions there for installing Sphinx, build the LLVM
+HTML documentation by doing the following:
+
+.. code-block:: console
+
+ $ cd SRC_ROOT/docs
+ $ make -f Makefile.sphinx
+
+This creates a ``_build/html`` sub-directory with all of the HTML files, not
+just the generated ones.
+This directory corresponds to ``llvm.org/docs``.
+For example, ``_build/html/SphinxQuickstartTemplate.html`` corresponds to
+``llvm.org/docs/SphinxQuickstartTemplate.html``.
+The :doc:`SphinxQuickstartTemplate` is useful when creating a new document.
+
+Cross-Compiling LLVM
+--------------------
+
+It is possible to cross-compile LLVM itself. That is, you can create LLVM
+executables and libraries to be hosted on a platform different from the platform
+where they are built (a Canadian Cross build). To configure a cross-compile,
+supply the configure script with ``--build`` and ``--host`` options that are
+different. The values of these options must be legal target triples that your
+GCC compiler supports.
+
+The result of such a build is executables that are not runnable on on the build
+host (--build option) but can be executed on the compile host (--host option).
+
+Check :doc:`HowToCrossCompileLLVM` and `Clang docs on how to cross-compile in general
+<http://clang.llvm.org/docs/CrossCompilation.html>`_ for more information
+about cross-compiling.
+
+The Location of LLVM Object Files
+---------------------------------
+
+The LLVM build system is capable of sharing a single LLVM source tree among
+several LLVM builds. Hence, it is possible to build LLVM for several different
+platforms or configurations using the same source tree.
+
+This is accomplished in the typical autoconf manner:
+
+* Change directory to where the LLVM object files should live:
+
+ .. code-block:: console
+
+ % cd OBJ_ROOT
+
+* Run the ``configure`` script found in the LLVM source directory:
+
+ .. code-block:: console
+
+ % SRC_ROOT/configure
+
+The LLVM build will place files underneath *OBJ_ROOT* in directories named after
+the build type:
+
+Debug Builds with assertions enabled (the default)
+
+ Tools
+
+ ``OBJ_ROOT/Debug+Asserts/bin``
+
+ Libraries
+
+ ``OBJ_ROOT/Debug+Asserts/lib``
+
+Release Builds
+
+ Tools
+
+ ``OBJ_ROOT/Release/bin``
+
+ Libraries
+
+ ``OBJ_ROOT/Release/lib``
+
+Profile Builds
+
+ Tools
+
+ ``OBJ_ROOT/Profile/bin``
+
+ Libraries
+
+ ``OBJ_ROOT/Profile/lib``
Modified: llvm/trunk/docs/GettingStarted.rst
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/docs/GettingStarted.rst?rev=232135&r1=232134&r2=232135&view=diff
==============================================================================
--- llvm/trunk/docs/GettingStarted.rst (original)
+++ llvm/trunk/docs/GettingStarted.rst Thu Mar 12 20:58:14 2015
@@ -61,7 +61,37 @@ Here's the short story for getting up an
* ``cd llvm/projects``
* ``svn co http://llvm.org/svn/llvm-project/test-suite/trunk test-suite``
-#. Configure and build LLVM and Clang:
+#. Configure and build LLVM and Clang (Recommended process using CMake):
+
+ * ``cd where you want to build llvm``
+ * ``mkdir build``
+ * ``cd build``
+ * ``cmake -G <generator> [options] <path to llvm sources>``
+
+ Some common generators are:
+
+ * ``Unix Makefiles`` --- for generating make-compatible parallel makefiles.
+ * ``Ninja`` --- for generating `Ninja <http://martine.github.io/ninja/>`
+ build files.
+ * ``Visual Studio`` --- for generating Visual Studio projects and
+ solutions.
+ * ``Xcode`` --- for generating Xcode projects.
+
+ Some Common options:
+
+ * ``-DCMAKE_INSTALL_PREFIX=directory`` --- Specify for *directory* the full
+ pathname of where you want the LLVM tools and libraries to be installed
+ (default ``/usr/local``).
+
+ * ``-DCMAKE_BUILD_TYPE=type`` --- Valid options for *type* are Debug,
+ Release, RelWithDebInfo, and MinSizeRel. Default is Debug.
+
+ * ``-DLLVM_ENABLE_ASSERTIONS=On`` --- Compile with assertion checks enabled
+ (default is Yes for Debug builds, No for all other build types).
+
+ * For more information see `CMake <CMake.html>`_
+
+#. Configure and build LLVM and Clang (Alternate process using configure):
* ``cd where-you-want-to-build-llvm``
* ``mkdir build`` (for building without polluting the source dir)
@@ -87,11 +117,6 @@ Here's the short story for getting up an
* ``make check-all`` --- This run the regression tests to ensure everything
is in working order.
- * It is also possible to use `CMake <CMake.html>`_ instead of the makefiles.
- With CMake it is possible to generate project files for several IDEs:
- Xcode, Eclipse CDT4, CodeBlocks, Qt-Creator (use the CodeBlocks
- generator), KDevelop3.
-
* If you get an "internal compiler error (ICE)" or test failures, see
`below`.
@@ -134,7 +159,8 @@ Windows x64 x86-64
#. Code generation supported for Pentium processors and up
#. Code generation supported for 32-bit ABI only
#. To use LLVM modules on Win32-based system, you may configure LLVM
- with ``--enable-shared``.
+ with ``-DBUILD_SHARED_LIBS=On`` for CMake builds or ``--enable-shared``
+ for configure builds.
#. MCJIT not working well pre-v7, old JIT engine not supported any more.
Note that you will need about 1-3 GB of space for a full LLVM build in Debug
@@ -435,7 +461,7 @@ follows:
* ``cd where-you-want-llvm-to-live``
* Read-Only: ``svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm``
-* Read-Write:``svn co https://user@llvm.org/svn/llvm-project/llvm/trunk llvm``
+* Read-Write: ``svn co https://user@llvm.org/svn/llvm-project/llvm/trunk llvm``
This will create an '``llvm``' directory in the current directory and fully
populate it with the LLVM source code, Makefiles, test directories, and local
@@ -664,66 +690,61 @@ Local LLVM Configuration
------------------------
Once checked out from the Subversion repository, the LLVM suite source code must
-be configured via the ``configure`` script. This script sets variables in the
-various ``*.in`` files, most notably ``llvm/Makefile.config`` and
-``llvm/include/Config/config.h``. It also populates *OBJ_ROOT* with the
-Makefiles needed to begin building LLVM.
-
-The following environment variables are used by the ``configure`` script to
-configure the build system:
-
-+------------+-----------------------------------------------------------+
-| Variable | Purpose |
-+============+===========================================================+
-| CC | Tells ``configure`` which C compiler to use. By default, |
-| | ``configure`` will check ``PATH`` for ``clang`` and GCC C |
-| | compilers (in this order). Use this variable to override |
-| | ``configure``\'s default behavior. |
-+------------+-----------------------------------------------------------+
-| CXX | Tells ``configure`` which C++ compiler to use. By |
-| | default, ``configure`` will check ``PATH`` for |
-| | ``clang++`` and GCC C++ compilers (in this order). Use |
-| | this variable to override ``configure``'s default |
-| | behavior. |
-+------------+-----------------------------------------------------------+
-
-The following options can be used to set or enable LLVM specific options:
-
-``--enable-optimized``
-
- Enables optimized compilation (debugging symbols are removed and GCC
- optimization flags are enabled). Note that this is the default setting if you
- are using the LLVM distribution. The default behavior of a Subversion
- checkout is to use an unoptimized build (also known as a debug build).
-
-``--enable-debug-runtime``
-
- Enables debug symbols in the runtime libraries. The default is to strip debug
- symbols from the runtime libraries.
-
-``--enable-jit``
-
- Compile the Just In Time (JIT) compiler functionality. This is not available
- on all platforms. The default is dependent on platform, so it is best to
- explicitly enable it if you want it.
-
-``--enable-targets=target-option``
-
- Controls which targets will be built and linked into llc. The default value
- for ``target_options`` is "all" which builds and links all available targets.
- The "host" target is selected as the target of the build host. You can also
- specify a comma separated list of target names that you want available in llc.
- The target names use all lower case. The current set of targets is:
-
- ``aarch64, arm, arm64, cpp, hexagon, mips, mipsel, mips64, mips64el, msp430,
- powerpc, nvptx, r600, sparc, systemz, x86, x86_64, xcore``.
-
-``--enable-doxygen``
-
- Look for the doxygen program and enable construction of doxygen based
- documentation from the source code. This is disabled by default because
- generating the documentation can take a long time and producess 100s of
- megabytes of output.
+be configured before being built. For instructions using autotools please see
+`Building LLVM With Autotools <BuildingLLVMWithAutotools.html>`_. The
+recommended process uses CMake. Unlinke the normal ``configure`` script, CMake
+generates the build files in whatever format you request as well as various
+``*.inc`` files, and ``llvm/include/Config/config.h``.
+
+Variables are passed to ``cmake`` on the command line using the format
+``-D<variable name>=<value>``. The following variables are some common options
+used by people developing LLVM.
+
++-------------------------+----------------------------------------------------+
+| Variable | Purpose |
++=========================+====================================================+
+| CMAKE_C_COMPILER | Tells ``cmake`` which C compiler to use. By |
+| | default, this will be /usr/bin/cc. |
++-------------------------+----------------------------------------------------+
+| CMAKE_CXX_COMPILER | Tells ``cmake`` which C++ compiler to use. By |
+| | default, this will be /usr/bin/c++. |
++-------------------------+----------------------------------------------------+
+| CMAKE_BUILD_TYPE | Tells ``cmake`` what type of build you are trying |
+| | to generate files for. Valid options are Debug, |
+| | Release, RelWithDebInfo, and MinSizeRel. Default |
+| | is Debug. |
++-------------------------+----------------------------------------------------+
+| CMAKE_INSTALL_PREFIX | Specifies the install directory to target when |
+| | running the install action of the build files. |
++-------------------------+----------------------------------------------------+
+| LLVM_TARGETS_TO_BUILD | A semicolon delimited list controlling which |
+| | targets will be built and linked into llc. This is |
+| | equivalent to the ``--enable-targets`` option in |
+| | the configure script. The default list is defined |
+| | as ``LLVM_ALL_TARGETS``, and can be set to include |
+| | out-of-tree targets. The default value includes: |
+| | ``AArch64, ARM, CppBackend, Hexagon, |
+| | Mips, MSP430, NVPTX, PowerPC, R600, Sparc, |
+| | SystemZ, X86, XCore``. |
++-------------------------+----------------------------------------------------+
+| LLVM_ENABLE_DOXYGEN | Build doxygen-based documentation from the source |
+| | code This is disabled by default because it is |
+| | slow and generates a lot of output. |
++-------------------------+----------------------------------------------------+
+| LLVM_ENABLE_SPHINX | Build sphinx-based documentation from the source |
+| | code. This is disabled by default because it is |
+| | slow and generates a lot of output. |
++-------------------------+----------------------------------------------------+
+| LLVM_BUILD_LLVM_DYLIB | Generate libLLVM.so. This library contains a |
+| | default set of LLVM components that can be |
+| | overridden with ``LLVM_DYLIB_COMPONENTS``. The |
+| | default contains most of LLVM and is defined in |
+| | ``tools/llvm-shlib/CMakelists.txt``. |
++-------------------------+----------------------------------------------------+
+| LLVM_OPTIMIZED_TABLEGEN | Builds a release tablegen that gets used during |
+| | the LLVM build. This can dramatically speed up |
+| | debug builds. |
++-------------------------+----------------------------------------------------+
To configure LLVM, follow these steps:
@@ -733,47 +754,52 @@ To configure LLVM, follow these steps:
% cd OBJ_ROOT
-#. Run the ``configure`` script located in the LLVM source tree:
+#. Run the ``cmake``:
.. code-block:: console
- % SRC_ROOT/configure --prefix=/install/path [other options]
+ % cmake -G "Unix Makefiles" -DCMAKE_INSTALL_PREFIX=prefix=/install/path
+ [other options] SRC_ROOT
Compiling the LLVM Suite Source Code
------------------------------------
-Once you have configured LLVM, you can build it. There are three types of
-builds:
+Unlike with autotools, with CMake your build type is defined at configuration.
+If you want to change your build type, you can re-run cmake with the following
+invocation:
+
+ .. code-block:: console
+
+ % cmake -G "Unix Makefiles" -DCMAKE_BUILD_TYPE=type SRC_ROOT
+
+Between runs, CMake preserves the values set for all options. CMake has the
+following build types defined:
+
+Debug
+
+ These builds are the default. The build system will compile the tools and
+ libraries unoptimized, with debugging information, and asserts enabled.
+
+Release
+
+ For these builds, the build system will compile the tools and libraries
+ with optimizations enabled and not generate debug info. CMakes default
+ optimization level is -O3. This can be configured by setting the
+ ``CMAKE_CXX_FLAGS_RELEASE`` variable on the CMake command line.
-Debug Builds
+RelWithDebInfo
- These builds are the default when one is using a Subversion checkout and
- types ``gmake`` (unless the ``--enable-optimized`` option was used during
- configuration). The build system will compile the tools and libraries with
- debugging information. To get a Debug Build using the LLVM distribution the
- ``--disable-optimized`` option must be passed to ``configure``.
-
-Release (Optimized) Builds
-
- These builds are enabled with the ``--enable-optimized`` option to
- ``configure`` or by specifying ``ENABLE_OPTIMIZED=1`` on the ``gmake`` command
- line. For these builds, the build system will compile the tools and libraries
- with GCC optimizations enabled and strip debugging information from the
- libraries and executables it generates. Note that Release Builds are default
- when using an LLVM distribution.
-
-Profile Builds
-
- These builds are for use with profiling. They compile profiling information
- into the code for use with programs like ``gprof``. Profile builds must be
- started by specifying ``ENABLE_PROFILING=1`` on the ``gmake`` command line.
+ These builds are useful when debugging. They generate optimized binaries with
+ debug information. CMakes default optimization level is -O2. This can be
+ configured by setting the ``CMAKE_CXX_FLAGS_RELWITHDEBINFO`` variable on the
+ CMake command line.
Once you have LLVM configured, you can build it by entering the *OBJ_ROOT*
directory and issuing the following command:
.. code-block:: console
- % gmake
+ % make
If the build fails, please `check here`_ to see if you are using a version of
GCC that is known not to compile LLVM.
@@ -784,110 +810,51 @@ command:
.. code-block:: console
- % gmake -j2
+ % make -j2
There are several special targets which are useful when working with the LLVM
source code:
-``gmake clean``
+``make clean``
Removes all files generated by the build. This includes object files,
generated C/C++ files, libraries, and executables.
-``gmake dist-clean``
-
- Removes everything that ``gmake clean`` does, but also removes files generated
- by ``configure``. It attempts to return the source tree to the original state
- in which it was shipped.
-
-``gmake install``
+``make install``
Installs LLVM header files, libraries, tools, and documentation in a hierarchy
- under ``$PREFIX``, specified with ``./configure --prefix=[dir]``, which
+ under ``$PREFIX``, specified with ``CMAKE_INSTALL_PREFIX``, which
defaults to ``/usr/local``.
-``gmake -C runtime install-bytecode``
-
- Assuming you built LLVM into $OBJDIR, when this command is run, it will
- install bitcode libraries into the GCC front end's bitcode library directory.
- If you need to update your bitcode libraries, this is the target to use once
- you've built them.
-
-Please see the `Makefile Guide <MakefileGuide.html>`_ for further details on
-these ``make`` targets and descriptions of other targets available.
-
-It is also possible to override default values from ``configure`` by declaring
-variables on the command line. The following are some examples:
-
-``gmake ENABLE_OPTIMIZED=1``
-
- Perform a Release (Optimized) build.
-
-``gmake ENABLE_OPTIMIZED=1 DISABLE_ASSERTIONS=1``
-
- Perform a Release (Optimized) build without assertions enabled.
-
-``gmake ENABLE_OPTIMIZED=0``
-
- Perform a Debug build.
-
-``gmake ENABLE_PROFILING=1``
-
- Perform a Profiling build.
-
-``gmake VERBOSE=1``
+``make docs-llvm-html``
- Print what ``gmake`` is doing on standard output.
-
-``gmake TOOL_VERBOSE=1``
-
- Ask each tool invoked by the makefiles to print out what it is doing on
- the standard output. This also implies ``VERBOSE=1``.
-
-Every directory in the LLVM object tree includes a ``Makefile`` to build it and
-any subdirectories that it contains. Entering any directory inside the LLVM
-object tree and typing ``gmake`` should rebuild anything in or below that
-directory that is out of date.
-
-This does not apply to building the documentation.
-LLVM's (non-Doxygen) documentation is produced with the
-`Sphinx <http://sphinx-doc.org/>`_ documentation generation system.
-There are some HTML documents that have not yet been converted to the new
-system (which uses the easy-to-read and easy-to-write
-`reStructuredText <http://sphinx-doc.org/rest.html>`_ plaintext markup
-language).
-The generated documentation is built in the ``SRC_ROOT/docs`` directory using
-a special makefile.
-For instructions on how to install Sphinx, see
-`Sphinx Introduction for LLVM Developers
-<http://lld.llvm.org/sphinx_intro.html>`_.
-After following the instructions there for installing Sphinx, build the LLVM
-HTML documentation by doing the following:
-
-.. code-block:: console
-
- $ cd SRC_ROOT/docs
- $ make -f Makefile.sphinx
-
-This creates a ``_build/html`` sub-directory with all of the HTML files, not
-just the generated ones.
-This directory corresponds to ``llvm.org/docs``.
-For example, ``_build/html/SphinxQuickstartTemplate.html`` corresponds to
-``llvm.org/docs/SphinxQuickstartTemplate.html``.
-The :doc:`SphinxQuickstartTemplate` is useful when creating a new document.
+ If configured with ``-DLLVM_ENABLE_SPHINX=On``, this will generate a directory
+ at ``OBJ_ROOT/docs/html`` which contains the HTML formatted documentation.
Cross-Compiling LLVM
--------------------
It is possible to cross-compile LLVM itself. That is, you can create LLVM
executables and libraries to be hosted on a platform different from the platform
-where they are built (a Canadian Cross build). To configure a cross-compile,
-supply the configure script with ``--build`` and ``--host`` options that are
-different. The values of these options must be legal target triples that your
-GCC compiler supports.
+where they are built (a Canadian Cross build). To generate build files for
+cross-compiling CMake provides a variable ``CMAKE_TOOLCHAIN_FILE`` which can
+define compiler flags and variables used during the CMake test operations.
The result of such a build is executables that are not runnable on on the build
-host (--build option) but can be executed on the compile host (--host option).
+host but can be executed on the target. As an example the following CMake
+invocation can generate build files targeting iOS. This will work on Mac OS X
+with the latest Xcode:
+
+.. code-block:: console
+
+ % cmake -G "Ninja" -DCMAKE_OSX_ARCHITECTURES=âarmv7;armv7s;arm64"
+ -DCMAKE_TOOLCHAIN_FILE=<PATH_TO_LLVM>/cmake/platforms/iOS.cmake
+ -DCMAKE_BUILD_TYPE=Release -DLLVM_BUILD_RUNTIME=Off -DLLVM_INCLUDE_TESTS=Off
+ -DLLVM_INCLUDE_EXAMPLES=Off -DLLVM_ENABLE_BACKTRACES=Off [options]
+ <PATH_TO_LLVM>
+
+Note: There are some additional flags that need to be passed when building for
+iOS due to limitations in the iOS SDK.
Check :doc:`HowToCrossCompileLLVM` and `Clang docs on how to cross-compile in general
<http://clang.llvm.org/docs/CrossCompilation.html>`_ for more information
@@ -908,44 +875,25 @@ This is accomplished in the typical auto
% cd OBJ_ROOT
-* Run the ``configure`` script found in the LLVM source directory:
+* Run ``cmake``:
.. code-block:: console
- % SRC_ROOT/configure
-
-The LLVM build will place files underneath *OBJ_ROOT* in directories named after
-the build type:
+ % cmake -G "Unix Makefiles" SRC_ROOT
-Debug Builds with assertions enabled (the default)
+The LLVM build will create a structure underneath *OBJ_ROOT* that matches the
+LLVM source tree. At each level where source files are present in the source
+tree there will be a corresponding ``CMakeFiles`` directory in the *OBJ_ROOT*.
+Underneath that directory there is another directory with a name ending in
+``.dir`` under which you'll find object files for each source.
- Tools
+For example:
- ``OBJ_ROOT/Debug+Asserts/bin``
-
- Libraries
-
- ``OBJ_ROOT/Debug+Asserts/lib``
-
-Release Builds
-
- Tools
-
- ``OBJ_ROOT/Release/bin``
-
- Libraries
-
- ``OBJ_ROOT/Release/lib``
-
-Profile Builds
-
- Tools
-
- ``OBJ_ROOT/Profile/bin``
-
- Libraries
-
- ``OBJ_ROOT/Profile/lib``
+ .. code-block:: console
+
+ % cd llvm_build_dir
+ % find lib/Support/ -name APFloat*
+ lib/Support/CMakeFiles/LLVMSupport.dir/APFloat.cpp.o
Optional Configuration Items
----------------------------
Modified: llvm/trunk/docs/index.rst
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/docs/index.rst?rev=232135&r1=232134&r2=232135&view=diff
==============================================================================
--- llvm/trunk/docs/index.rst (original)
+++ llvm/trunk/docs/index.rst Thu Mar 12 20:58:14 2015
@@ -70,6 +70,7 @@ representation.
CommandGuide/index
GettingStarted
GettingStartedVS
+ BuildingLLVMWithAutotools
FAQ
Lexicon
HowToAddABuilder
@@ -105,6 +106,10 @@ representation.
An addendum to the main Getting Started guide for those using Visual Studio
on Windows.
+:doc:`BuildingLLVMWithAutotools`
+ An addendum to the Getting Started guide with instructions for building LLVM
+ with the Autotools build system.
+
:doc:`tutorial/index`
Tutorials about using LLVM. Includes a tutorial about making a custom
language with LLVM.
More information about the llvm-commits
mailing list