1. A computer program product comprising one or more computer storage media having thereon computer-executable instructions that are structured such that, when executed by the one or more processors of a computing system, causes the computing system to perform a method for generating a plurality of overlaid dependency graphs for code that includes a plurality of code portions, the method comprising acts of: accessing a first plurality of nodes that each comprises a data structure corresponding to a code portion of the plurality of code portions represented by the first plurality of nodes; for the first plurality of nodes, generating a higher level dependency graph by performing the following further acts: calculating a dependency for one more nodes of the first plurality of nodes by determining that said one or more nodes are depending nodes that correspond to a depending code portion that depends on an affecting code portion corresponding to an affecting node that is included among the first plurality of nodes; recording the dependency in a manner associated with each node in the first plurality of nodes for which a dependency is calculated; and recording a method of dependency calculation in a manner associated with each calculated dependency for said one or more nodes of the first plurality of nodes; accessing a second plurality of nodes that each comprises a data structure corresponding to a code portion of the plurality of code portions represented by the second plurality of nodes; for the second plurality of nodes, generating a lower level dependency graph by performing the following further acts: calculating a dependency for one more nodes of the second plurality of nodes by determining that said one or more nodes are depending nodes that correspond to a depending code portion that depends on an affecting code portion corresponding to an affecting node that is included among the second plurality of nodes; recording the dependency in a manner associated with each node in the second plurality of nodes for which a dependency is calculated; and recording a method of dependency calculation in a manner associated with each calculated dependency for said one or more nodes of the second plurality of nodes; wherein the lower level dependency graph represents dependency relationships contained within at least one node of the first plurality of nodes, so that the lower level dependency graph is overlaid by the higher level dependency graph; and wherein at least one of the higher or lower level dependency graphs is generated in two phases, and wherein during the first phase the generated dependency graph is first generated prior to runtime and the graph dependencies are calculated based on static analysis, and during the second phase the generated dependency graph is updated based on dependencies calculated using dynamic analysis during a runtime.