graph based intermediate representation and backend for optimising compilers
C Python C++ Perl 6 Perl CMake Other
Andreas Fried
Andreas Fried Another buildbot test.
Latest commit 78d5337 Jul 17, 2018

libFirm -- A graph based SSA intermediate representation


The Firm library implements the Firm intermediate representation (ir). You can find an old description of Firm in [TLB:99].

libFirm contains algorithms for construction of the SSA form directly from the attributed syntax tree. A set of analyses and optimization phases is provided. This version includes a complete backend for the IA32 and SPARC architecture, as well as unfinished backends for MIPS, ARM, and AMD64.

Building and Installation

Prerequisites for the build:

  • Python (2.7.x or >=3.3 are supported)
  • Perl
  • an ANSI C99 compiler (gcc, clang, icc are known to work)
  • Git

Building with make

Just type 'make' in the source directory. The results are put into a directory called "build". You can override the existing preprocessor, compiler and linker flags by creating a 'config.mak' file.

Building with cmake

libFirm has an additional cmake build system. CMake is a more complex build system than the make based one and most libFirm developers do not use it. However it can adapt the compiler and linker flags to build shared libraries for a wider range of systems, provides an installation target and is often more familiar for people preparing packages for distribution.

Repository Structure

  include/libfirm/   # public API
  ir/                # nearly all the code
  ir/adt/            # containers and other generic data types
  ir/ana/            # analysis (for optimizations)
  ir/be/             # backends (x86, sparc, amd64, etc)
  ir/common/         # utility stuff
  ir/ident/          # identifier data structure
  ir/ir/             # core data types of intermediate representation
  ir/kaps/           # PBQP solver
  ir/libcore/        # utility stuff
  ir/lower/          # lowering phases from high-level to low-level mechanisms
  ir/lpp/            # interface for external ILP solvers
  ir/obstack/        # arena memory allocator
  ir/opt/            # optimization phases
  ir/stat/           # statistics
  ir/tr/             # type representation
  ir/tv/             # target values (architecture-independent arithmetic)
  scripts/           # generator scripts, firm node specification
  unittests/         # unittests
  build/             # build system generates stuff here

Further Information and Contact

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