Abstract: The decomposition of instructions into separate sequential and branch instruction code sections. In one embodiment, a system including a first store to store a first code section including only branch instructions and a second store to store a second code section including only sequential instructions. In another embodiment, the system also includes a processor having a first engine to process the branch instructions, and a second engine to process the sequential instructions.

Abstract: A method and apparatus for prefetching data in a computer system that inces a processor. A prefetch instruction is executed and, in response, data is prefetched from a memory location. It is determined if a memory exception occurred during the prefetching of the data. If a memory exception occurred, the exception is handled if the prefetch instruction indicates to do so.

Abstract: An apparatus for use in a computer system comprises a first storage area and a circuit, coupled to the first storage area, configured to perform a comparison of a data element A with a data element B. In response to a single instruction, the circuit performs the comparison and outputs a condition field of at least one bits when the comparison of A and B is TRUE, or else the circuit outputs the ones-complement of the condition field when the comparison of A and B is FALSE. The circuit may be used in conjunction with a sequence of instructions to select bits from a first data element and bits from a second data element using the one or more condition field bits.

Abstract: A method and apparatus for prefetching data in a computer system that includes a processor. A prefetch instruction is executed and, in response, data is prefetched from a memory location. It is determined if a memory exception occurred during the prefetching of the data. If a memory exception occurred, the exception is handled if the prefetch instruction indicates to do so.

Abstract: The inventive system and method allows for software control of hardware drral of exceptions in speculative operations, and comprises three components. The first component is processor stored information which reflects the code generation strategy of applications and is used by hardware and the operating system to control exception deferral. The second component is processor stored information set by the operating system to specify to hardware which type of faults should be automatically deferred. The third component is further processor stored information which indicates to the hardware to defer certain exception causing aspects of the speculative operation, while performing other non excepting aspects of the speculative operation. The stored information is set after the operating system exception handler has unsuccessfully attempted fault resolution.

Abstract: In a processor where separate integer and floating point units are utilized, conditions generated in the integer unit are transferred and made compatible for use in the floating point unit by floating point conditional branch and move operations. Conversely, conditions generated in the floating point unit are transferred and made compatible for use in the integer unit by integer conditional branch and move operations. By providing semantic compatibility of conditions with conditional operations in both integer and floating point units, conditions can be generated in one numeric unit and operated in the other.

Abstract: The present invention provides a method and apparatus for restoring a predicate register set. One embodiment of the invention includes decoding a first instruction which specifies a restoring operation to be performed on a predicate register set. In response to the first instruction, a mask is used to select a plurality of the predicate registers that are to be restored. The mask of the present invention consists of a first set of bits, with each bit of the first set of bits corresponding to a register in the predicate register set. When a bit of the first set of bits is set to one, the predicate register corresponding to that bit is restored. In one embodiment, the mask further includes one bit corresponding to a plurality of registers in the predicate register set, wherein when that bit is set to one, the plurality of registers corresponding to that bit are restored.

Abstract: An apparatus and method for improving the performance of superscalar pipelined computers using branch prediction and verification that the predicted branch is correct. A predicted branch may be resolved in one of two distinct pipeline stages, and a method is provided for handling branches that are resolved in either of the pipeline stages. A branch verification method is provided that verifies that the architecturally correct instructions are in the decode and execution stages. Furthermore, two sets of prefetch buffers are provided to allow branch prediction when multiple clock decoding is required by a multi-clock instruction.

Abstract: An interleaved cache is used for multiple data accesses per clock in a microprocessor. The cache includes a storage array having multiple banks of single-ported memory cells for storing data, a bank selector for selecting banks in the storage array simultaneously according to the multiple data accesses, and a datapath for transfering data between execution units in the microprocessor and the storage array. The cache of the present invention also includes contention logic for prioritizing the multiple data accesses when multiple data accesses are to be same bank.

Abstract: An apparatus and method for improving the performance of superscalar pipelined computers using branch prediction and verification that the predicted branch is correct. A predicted branch may be resolved in one of two distinct pipeline stages, and a method is provided for handling branches that are resolved in either of the pipeline stages. A branch verification method is provided that verifies that the architecturally correct instructions are in the decode and execution stages. Furthermore, two sets of prefetch buffers are provided to allow branch prediction when multiple clock decoding is required by a multi-clock instruction.