mirror of
https://github.com/RPCS3/llvm-mirror.git
synced 2024-11-22 10:42:39 +01:00
b5ab75c303
As per the very positive feedback from llvm-dev (http://lists.llvm.org/pipermail/llvm-dev/2015-November/092150.html), this commit officially deprecates the LLVM autoconf-based build system. Anyone still using it should switch to CMake. llvm-svn: 252520
339 lines
12 KiB
ReStructuredText
339 lines
12 KiB
ReStructuredText
====================================
|
|
Building LLVM With Autotools
|
|
====================================
|
|
|
|
.. contents::
|
|
:local:
|
|
|
|
.. warning::
|
|
|
|
Building LLVM with autoconf is deprecated as of 3.8. The autoconf build
|
|
system will be removed in 3.9. Please migrate to using CMake. For more
|
|
information see: `Building LLVM with CMake <CMake.html>`_
|
|
|
|
Overview
|
|
========
|
|
|
|
This document details how to use the LLVM autotools based build system to
|
|
configure and build LLVM from source. The normal developer process using CMake
|
|
is detailed `here <GettingStarted.html#check-here>`_.
|
|
|
|
A Quick Summary
|
|
---------------
|
|
|
|
#. Configure and build LLVM and Clang:
|
|
|
|
* ``cd where-you-want-to-build-llvm``
|
|
* ``mkdir build`` (for building without polluting the source dir)
|
|
* ``cd build``
|
|
* ``../llvm/configure [options]``
|
|
Some common options:
|
|
|
|
* ``--prefix=directory`` --- Specify for *directory* the full pathname of
|
|
where you want the LLVM tools and libraries to be installed (default
|
|
``/usr/local``).
|
|
|
|
* ``--enable-optimized`` --- Compile with optimizations enabled (default
|
|
is NO).
|
|
|
|
* ``--enable-assertions`` --- Compile with assertion checks enabled
|
|
(default is YES).
|
|
|
|
* ``make [-j]`` --- The ``-j`` specifies the number of jobs (commands) to run
|
|
simultaneously. This builds both LLVM and Clang for Debug+Asserts mode.
|
|
The ``--enable-optimized`` configure option is used to specify a Release
|
|
build.
|
|
|
|
* ``make check-all`` --- This run the regression tests to ensure everything
|
|
is in working order.
|
|
|
|
* If you get an "internal compiler error (ICE)" or test failures, see
|
|
`here <GettingStarted.html#check-here>`_.
|
|
|
|
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
|
|
|
|
% $LLVM_SRC_DIR/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 ``$LLVM_SRC_DIR/configure --prefix=[dir]``, which
|
|
defaults to ``/usr/local``.
|
|
|
|
``gmake -C runtime install-bytecode``
|
|
|
|
Assuming you built LLVM into $OBJDIR, when this command is run, it will
|
|
install bitcode libraries into the GCC front end's bitcode library directory.
|
|
If you need to update your bitcode libraries, this is the target to use once
|
|
you've built them.
|
|
|
|
Please see the `Makefile Guide <MakefileGuide.html>`_ for further details on
|
|
these ``make`` targets and descriptions of other targets available.
|
|
|
|
It is also possible to override default values from ``configure`` by declaring
|
|
variables on the command line. The following are some examples:
|
|
|
|
``gmake ENABLE_OPTIMIZED=1``
|
|
|
|
Perform a Release (Optimized) build.
|
|
|
|
``gmake ENABLE_OPTIMIZED=1 DISABLE_ASSERTIONS=1``
|
|
|
|
Perform a Release (Optimized) build without assertions enabled.
|
|
|
|
``gmake ENABLE_OPTIMIZED=0``
|
|
|
|
Perform a Debug build.
|
|
|
|
``gmake ENABLE_PROFILING=1``
|
|
|
|
Perform a Profiling build.
|
|
|
|
``gmake VERBOSE=1``
|
|
|
|
Print what ``gmake`` is doing on standard output.
|
|
|
|
``gmake TOOL_VERBOSE=1``
|
|
|
|
Ask each tool invoked by the makefiles to print out what it is doing on
|
|
the standard output. This also implies ``VERBOSE=1``.
|
|
|
|
Every directory in the LLVM object tree includes a ``Makefile`` to build it and
|
|
any subdirectories that it contains. Entering any directory inside the LLVM
|
|
object tree and typing ``gmake`` should rebuild anything in or below that
|
|
directory that is out of date.
|
|
|
|
This does not apply to building the documentation.
|
|
LLVM's (non-Doxygen) documentation is produced with the
|
|
`Sphinx <http://sphinx-doc.org/>`_ documentation generation system.
|
|
There are some HTML documents that have not yet been converted to the new
|
|
system (which uses the easy-to-read and easy-to-write
|
|
`reStructuredText <http://sphinx-doc.org/rest.html>`_ plaintext markup
|
|
language).
|
|
The generated documentation is built in the ``$LLVM_SRC_DIR/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 $LLVM_SRC_DIR/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
|
|
|
|
% $LLVM_SRC_DIR/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``
|