Intermediate language representation and modification

摘要

A system and method for facilitating analysis and modification of a computer program. A directed graph is generated from an intermediate language representation of a computer program function, with a node representing each instruction. Meta-edges or meta-nodes are inserted into the directed graph to facilitate location of instruction nodes. One type of meta-edge is a back edge that identifies branch instruction nodes. Some meta-nodes may identify instructions of a specific type. Some meta-nodes may identify exception blocks and corresponding handlers. Analysis of a program function may include insertion of new instructions prior to execution of the function.

主权项

1. A computer-implemented method for modifying execution of a computer program function having a plurality of instructions, comprising:
a) in response to detecting an invocation of the computer program function, generating a directed graph representing the computer program function, the directed graph including a plurality of instruction nodes, each instruction node representing a corresponding instruction of the plurality of instructions; b) inserting, into the directed graph, one or more meta-nodes, the one or more meta-nodes including a first edge to an instruction node of the directed graph corresponding to an instruction of an exception block and a second edge to an instruction node of the directed graph corresponding to a handler associated with the exception block; and c) employing the one or more meta-nodes to perform at least one of adding or removing at least one other instruction node to the directed graph; and d) translating the directed graph to an intermediate language representation of the computer program function.