Method for handling 32 bit results for an out-of-order processor with a 64 bit architecture

摘要

The present invention discloses a method and an implementation scheme to handle instructions in an out-of-order processor that write a 32 bit result into a 64-bit wide register. The 64-bit architecture specifies that the 64-bit result has to be constructed from the 32-bit result by leaving the remaining overhanging 32 bits unchanged. To handle the setting of the 32 bits that have to be unchanged here a so-called extract instruction (810) is disclosed which writes the 'overhanging' bit portion not into its own result field but into the result field of the subsequent instruction (for example a Load Address (LA) instruction (510). The invention is illustrated for the write of a 32 bit result into a 64-bit register but it is applicable for other bitwidth as well -like the write of 64 bit result into a 128-bit register.