COMPILER ALLOCATING A REGISTER TO A DATA ITEM USED BETWEEN A USE AND STORE OF ANOTHER DATA ITEM PREVIOUSLY ALLOCATED TO THE REGISTER

A compiler includes a register allocation method making use of the concept of assigning temporary items to lifetime holes if such holes exist that are suitable. The compiler includes a front end for converting the input code to an intermediate representation, then this input representation is traversed to identify all of the temporary items, and to find all of the holes in the temporary items. Lists are maintained of the identified temporaries and holes. Register allocation then includes assigning temporaries to registers so long as there are free registers, and if holes are available in already-assigned temporaries then these holes are used in assigning registers. After all the available registers and holes are used, remaining temporaries are unallocated and thus represent memory references.