Abstract: A multithread pipelined instruction decoder to clock, clear and stall an instruction decode pipeline of a multi-threaded machine to maximize performance and minimize power. A shadow pipeline shadows the instruction decode pipeline maintaining a the thread-identification and instruction-valid bits for each pipestage of the instruction decoder. The thread-id and valid bits are used to control the clear, clock, and stall of each pipestage of the instruction decoder. Instructions of one thread can be cleared without impacting instructions of another thread in the decode pipeline. In some cases, instructions of one thread can be stalled without impacting instructions of another thread in the decode pipeline. In the present invention, pipestages are clocked only when a valid instruction needs to advance in order to conserve power and to minimize stalling.

Abstract: A method of linear space target address generation for a relative branch is described. The method includes generating a selection signal, and generating a linear space target address using the selection signal by generating a plurality of corrected target addresses and selecting the linear space target address from the plurality of corrected target addresses using the selection signal.

Abstract: A method and circuit for linear space target address generation for a relative branch is described. A selection signal is generated to be used in generating a linear space target address. The generation of the linear space target address includes generating multiple corrected target addresses and selecting the linear space target address from the multiple corrected target addresses using the selection signal. The process of generating multiple corrected target addresses includes generating first, second, and third corrected target addresses. The first corrected target address is generated using an address and a displacement. The second corrected target address is generated using the address, displacement, and a second adder correction value. The third corrected target address is generated using the address, displacement, and a third adder correction value. A multiplexer outputs the first, second, or third corrected target address using the selection signal.