Abstract: Methods of predicting stack pointer values of variables stored in a stack are described. When an instruction is seen which stores a variable in the stack in a position offset from the stack pointer, an entry is added to a data structure which identifies the physical register which currently stores the stack pointer, the physical register which stores the value of the variable and the offset value. Subsequently when an instruction to load a variable from the stack from a position which is identified by reference to the stack pointer is seen, the data structure is searched to see if there is a corresponding entry which includes the same offset and the same physical register storing the stack pointer as the load instruction. If a corresponding entry is found the architectural register in the load instruction is mapped to the physical register storing the value of the variable from the entry.