Abstract: A system and a method is described for freeing renaming registers that have been allocated to architectural registers prior to another instruction redefining the architectural register. Renaming registers are used by a processor to dynamically execute instructions out-of-order. The present invention may be employed by any single or multi-threaded processor that executes instructions out-of-order. A mechanism is described for freeing renaming registers that consists of a set of instructions, used by a compiler, to indicate to the processor when it can free the physical (renaming) register that is allocated to a particular architectural register. This mechanism permits the renaming register to be reassigned or reallocated to store another value as soon as the renaming register is no longer needed for allocation to the architectural register.

Abstract: A system and a method is described for freeing renaming registers that have been allocated to architectural registers prior to another instruction redefining the architectural register. Renaming registers are used by a processor to dynamically execute instructions out-of-order. The present invention may be employed by any single or multi-threaded processor that executes instructions out-of-order. A mechanism is described for freeing renaming registers that consists of a set of instructions, used by a compiler, to indicate to the processor when it can free the physical (renaming) register that is allocated to a particular architectural register. This mechanism permits the renaming register to be reassigned or reallocated to store another value as soon as the renaming register is no longer needed for allocation to the architectural register.

Abstract: A method and organization for implementing the registers required in a computer system supporting multithreading and dynamic out-of-order execution. Multithreaded computer systems are those in which the processor supports multiple contexts (threads), and either rapid context switching from thread to thread or scheduling of instructions from different threads within a single cycle. An important component of processors for such systems is the register file; the processor needs a large register file or resource to provide the registers used for the threads. One form of the invention maintains a set of private architecturally specified registers, and a set of private renaming register for each different thread. In the other three embodiments, sharing of renaming registers between different threads is permitted, to enable a reduction in the total number of registers required.