Abstract: A method and apparatus are disclosed for staggering execution of an instruction. According to one embodiment of the invention, a single macro instruction is received wherein the single macro instruction specifies at least two logical registers and wherein the two logical registers respectively store a first and second packed data operands having corresponding data elements. An operation specified by the single macro instruction is then performed independently on a first and second plurality of the corresponding data elements from said first and second packed data operands at different times using the same circuit to independently generate a first and second plurality of resulting data elements. The first and second plurality of resulting data elements are stored in a single logical register as a third packed data operand.

Abstract: A method, apparatus, and system are provided for early data return indication mechanism. According to one embodiment, data cache is accessed for data in response to a request for the data, the request received from an instruction source, and the request waits for the data to be retrieved from memory if the data is not located in the data cache, and an early data ready indication is received at a resource scheduler, the early data ready indication being received prior to receiving a data ready indication referring to the data being ready to be retrieved from the memory.

Abstract: A filtering system for instruction segments determines whether a new instruction segment satisfies a predetermined filtering condition prior to storage. If the instruction segment fails the filtering condition, the new instruction segment is not stored. Various filtering conditions are available; but all filtering conditions test to determine whether it is more likely than not that a new instruction segment will be reused by the execution unit in the future.

Abstract: A page table walk is performed in response to a data translation lookaside buffer miss based on a speculative memory instruction. In the event of a data translation lookaside buffer miss, a page miss handler determines whether the memory micro-instruction causing the miss is a speculative or non-speculative micro-instruction. If non-speculative, the page miss handler performs a non-speculative page table walk. If the memory micro-instruction causing the miss is a speculative micro-instruction, the page miss handler initiates a speculative page table walk. While performing the speculative page table walk, the page miss handler determines whether page table memory accessed during the page table walk is speculateable or non-speculateable memory. If non-speculateable, the speculative page table walk is aborted. A micro-instruction assisted page table walk is performed whenever access or dirty bits must be set for the pages accessed in the page table walk.

Abstract: A plurality of global registers are provided on the microprocessor chip. One of a global registers is a frame pointer register containing the current frame pointer, and the remainder of the global registers are available to a current process as general registers. A plurality of floating point registers are also provided for use by the current process in execution of floating point arithmetic operations. A register set pool made up of a plurality of register sets is provided, each register set being comprised of a number of local registers. When a call instruction is decoded, a register set of local registers from the register set pool is allocated to the called procedure, and the frame pointer register is initialized. When a return instruction is decoded, the register set is freed for allocation to another procedure called by a subsequent call instruction.