libFIRM provides a graph-based intermediate representation (IR), which
operates exclusively in SSA-form, starting at IR construction until
assembler code emission.  It offers many analyses and optimizations,
provides extensive debug support and includes a backend framework.

* analyses: dominance, loop tree, execution frequency, control
  dependencies, call graph, rapid type, def-use, alias analysis,
  class hierarchy analysis
* optimizations: dead code elimination (happens implicitly), constant
  folding, local common subexpression elimination, arithmetic identities
  (happens on the fly), unreachable code elimination, global common
  subexpression elimination, code placement, strength reduction,
  scalar replacement, if-conversion, load/store optimization, control
  flow optimizations, reassociation, partial condition evaluation,
  tail recursion elimination, inlining, procedure cloning
* enhanced debugging support: extensive checkers, breakpoints on node
  creation, entity creation, graph dumping
* lowering of intrinsics, double word arithmetics, bitfields
* generic backend features:
  * novel SSA based register allocator
  * several SSA copy coalescing and spilling algorithms
  * algorithms for instruction and basic block scheduling
* working ia32 backend, unfinished backends for MIPS, ARM, PPC32
* handwritten recursive descent C89/C99 frontend available (lang/cparser)

Homepage:
https://libfirm.sourceforge.net/
