COMPILING DEVICE AND METHOD

A compiling device (100) configured to convert a source code computer program (102) into an object code computer program (106), the compiling device comprising-a processor circuit arranged to-parse (120) the source code computer program and generate a static single assignment (SSA) graph (122) for at least a portion of the source code computer program, and-search for a second subgraph (P) of the SSA graph, wherein a first subgraph (N) is a subgraph of the second subgraph (N⊆P), a sum of the bit sizes associated to incoming edges of the second subgraph being smaller than a sum of the bit sizes associated to incoming edges of the first graph, -implementing the second subgraph of the SSA graph in the object code computer program as a single operation thus omitting the assignments corresponding to edges of the first subgraph.