Module Llvmcfg

module Llvmcfg: sig .. end

Ocamlgraph persistent overlay for llvm.

This module allows to extract and manipulate a graph representing an llvm function with nodes representing the basicblocks.

The graph is persistent so that it's possible to transform the representation to perform analysis without modifying Llvm's IR.

type vertex_ = private {

	`id : int;`
	`block : Llvm.llbasicblock;`
	`phi : Llvm.llvalue list;`
	`instr : Llvm.llvalue list;`

}

include Graph.Sig.P

val vertex : block:Llvm.llbasicblock ->
       phi:Llvm.llvalue list -> instr:Llvm.llvalue list -> V.t

val of_llfunction : Llvm.llvalue -> (Llvm.llbasicblock -> vertex) * t

Create the graph representing an llvm function.

Returns a couple (f, g) where g is the graph and f associate an llvm basic bloc to a node in the graph.

Misc functions

val basicblocks_to_vertices : t -> Llvm.llbasicblock list -> vertex list

Get the vertices associated to some basicblocks.

Dot export

module Dot: sig .. end

Pretty print to dot graphviz format.

Cycle breaking

exception Not_reducible of t

val break_graph : ?start:vertex -> t -> Llvm.llbasicblock list * t

Break all the cycle in a graph, effectively returning a DAG. Also returns the list of broken basicblocks.

Each broken node is separated in two parts:

A phi node which contains only the phis and receives the input edges.
An instruction node which contains only the instruction and emit the output edges.

This implementation breaks the minimal amount of block possible.

A graph must be reducible for the algorithm to apply (which should be the case for all llvm's graphs) and the function will raise Llvmcfg.Not_reducible otherwise.

val break_by_list : t -> vertex list -> t

Similar to Llvmcfg.break_graph, but allows the user to provide the list of node to be broken.
Raises Invalid_argument if one of the node is not in the graph.