Method of splitting register live ranges

A computer program product for splitting live register ranges includes a computer readable storage medium and program instructions stored on the computer readable storage medium, the program instructions include instructions for identifying one or more H pathways comprising one or more H nodes having high register pressure using a backwards data flow in the graph, identifying an L pathway consisting of two or more L nodes using a depth first search, and inserting register splitting instructions for each symbolic register that is live in both the one or more H pathways and the L pathway. The register splitting instructions are inserted at a starting node of the one or more H pathways. Register merging instructions are inserted at an ending node of the one or more H pathways.