v0.9.9

1. Graphlib library

   Graphlib is a generic library that extends a well known
   OCamlGraph library. Graphlib uses its own, more reach and modern,
   Graph interface that is isomorphic to OCamlGraph's Sigs.P
   signature for persistant graphs. This interface is developed
   according to the Janestreet's style guidlines and depends on
   Core_kernel library. Other than the new interface, Graphlib
   provides several graph implementations, and generic algorithms. To
   make our algorithms polymorphic over chosen graph representation we
   use first-class modules, instead of functors, that makes library
   syntactically more light weight.

2. Refined IR.

   phi and arg terms were refined. a phi term now is a discriminated
   set of expressions, and arguments are made more like a defintions.

3. SSA form

   A transformation to a semipruned SSA form was added to a library

4. Changed Var interface.

   Variables can now be versioned, that plays well with SSA form. A
   version is used to represent the same variable but at different
   point of time.

5. Extended and fixed Trie data structure

   Several bug-fixes to a Trie data structure were made. Added
   walk function, that allows to perform generic queries over a trie.
   Also added prefix and suffix variants of String tries, as well as
   provided a functor to create tries with an array keys.

6. Redesigned abi interface.

   Now abi works on an IR level.

7. Added argument reconstruction algorithms.

   Two argument reconstructions algorithm, based on a new abi
   interface, were added - for ARM gnueabi ABI and System V amd64 ABI.
   Currently only parameters passed via registers are reconstructed.

8. Added free_vars algorithm to BIL and BIR terms.