Abstract: As a processor enters selected low-power modes, a cache is flushed of data by writing data stored at the cache to other levels of a memory hierarchy. The flushing of the cache allows the size of the cache to be reduced without suffering an additional performance penalty of writing the data at the reduced cache locations to the memory hierarchy. Accordingly, when the cache exits the selected low-power modes, it is sized to a minimum size by setting the number of ways of the cache to a minimum number. In response to defined events at the processing system, a cache controller changes the number of ways of each set of the cache.

Abstract: A size of a cache of a processing system is adjusted by ways, such that each set of the cache has the same number of ways. The cache is a set-associative cache, whereby each set includes a number of ways. In response to defined events at the processing system, a cache controller changes the number of ways of each set of the cache. For example, in response to a processor core indicating that it is entering a period of reduced activity, the cache controller can reduce the number of ways available in each set of the cache.

Abstract: There is disclosed, for use in an x86-compatible processor, a translation look-aside buffer (TLB) that stores region configuration bits (or attribute bits) associated with each physical address stored in the TLB and that makes the region configuration bits available at the same time that the physical address is generated/translated by the TLB. The TLB comprises: 1) a tag array capable of storing an untranslated address in one of N tag entries in the tag array; 2) a data array capable of storing a translated physical address corresponding to the untranslated address in one of N data entries in the data array; and 3) a region configuration array capable of storing region configuration bits associated with the translated physical address in one of N region configuration entries in the region configuration array.

Abstract: A scalar/vector processor capable of concurrent scaler and vector operations includes scalar resources to process scalar instructions, and vector resources adapted to be operated concurrently with the scalar resources and with one another to process vector instructions. The scalar resources include scalar registers, and the vector resources include vector registers. Decoding means decodes each of a number of address fields. Each field represents a register address to access alternatively one of the scalar registers or one of the vector registers depending on a value of the register address being above or below a selected moveable address value within a range of addresses encompassed by the address field.

Abstract: An improved high performance hardwired supercomputer data processing apparatus includes instruction means adpated to issue one and two parcel instructions. Instruction fetch means provides an instruction stream of two parcel items in sequence. Instruction decode means is responsive to each two parcel item for determining in one clock cycle whether the two parcel item is a single two parcel instruction or two one parcel instructions, for issuing each two parcel instruction for execution during the one clock cycle, and for issuing one then the other of the two one parcel instructions for execution in sequence during the one clock cycle and the next succeeding clock cycle.

Abstract: A delayed branch mechanism maintains the flow of an instruction pipeline in a scalar/vector processor having an instruction cache and including instruction fetch means, a program counter, and instruction decode/issue means coupled to the instruction cache by means of the instruction pipeline. Conditional branch instructions are rated as likely conditional branch instructions or unlikely conditional branch instructions based on a probability that their branch conditions will be met. A number of pipeline clock periods required for testing the branch conditions are determined. The likely conditional branch instructions are issued and executed including transferring a branch-to-address to the program counter during the number of pipeline clock periods irrespective of a successful meeting of the branch conditions. A number of useful instructions sufficient to issue within the number of pipeline clock periods are placed into the instruction stream following the likely conditional branch instructions.

Abstract: The present invention is an improved high performance scalar/vector processor. In the preferred embodiment, the scalar/vector processor is used in a multiprocessor system. The scalar/vector processor is comprised of a scalar processor for operating on scalar and logical instructions, including a plurality of independent functional units operably connected to the scalar processor, a vector processor for operating on vector instructions, including a plurality of independent functional units operably connected to the vector processor, and an instruction control mechanism for fetching both the scalar and vector instructions from an instruction cache and controlling the operation of those instructions in both the scalar and vector processor. The instruction control mechanism is designed to enhance the performance of the scalar/vector processor by keeping a multiplicity of pipelines substantially filled with a minimum number of gaps.

Abstract: A vector processing system includes a main memory, vector registers, vector resources for accessing memory to transfer vector data between main memory and the vector registers and to perform operations on the vector data. Data words stored in non-consecutive address locations of a segment of main memory are accessed for processing. Offset address values of a number of the data words are stored in consecutive elements of a first vector register. A vector gather instruction is executed which adds each offset address value to a base address value to calculate main memory addresses representing main memory storage locations of the data words, retrieves the data words from the main memory, and stores the data words in consecutive elements of a second vector register in an order corresponding to that in which the offset address values are stored in the first vector register.

Abstract: A sequence of conditional vector IF statements is processed by employing a mask register and a condition register. Each conditional vector IF statement is typically performed on two vector registers, each having vector elements. A first conditional vector IF statement in the sequence is processed for those vector elements corresponding to set bits in the mask register. Bits are set in the condition register to reflect those vector elements which correspond to the set bits in the mask register for which the conditional vector IF statement is satisfied. The contents of the condition register are then moved into the mask register. A next conditional vector IF statement in the sequence is then processed for those vector elements corresponding to the new set bits in the mask register. Bits are then set in the condition register to reflect those vector elements which correspond to the new set bits in the mask register for which the conditional vector IF statement is satisfied.

Abstract: A vector processor includes functional unit paths, each having an input and an output, and with at least one functional unit path including a plurality of pipelined functional elements coupled to the respective path input and output in parallel. The functional elements have different pipeline lengths to complete processing of operands applied to the path input. Program instruction initiation means responds to a first instruction to initiate processing of first operand data in a first of the functional elements, and responds to a second instruction to initiate the processing of second operand data in a second of the functional elements dependent upon completion of the first instruction but only if the second functional element has a pipeline length equal to or greater than the pipeline length of the first functional element.

Abstract: A method of accessing common memory in a cluster architecture for a highly parallel multiprocessor scaler/factor computer system using a plurality of segment registers in which is first determined whether a logical address is within a start and end range as defined by the segment registers and then relocating the logical address to a physical address using a displacement value in another segment register.

Abstract: The present invention is an improved high performance scalar/vector processor. In the preferred embodiment, the scalar/vector processor is used in a multiprocessor system. The scalar/vector processor is comprised of a scalar processor for operating on scalar and logical instructions, including a plurality of independent functional units operably connected to the scalar processor, a vector processor for operating on vector instructions, including a plurality of independent functional units operably connected to the vector processor, and an instruction control mechanism for fetching both the scalar and vector instructions from an instruction cache and controlling the operation of those instructions in both the scalar and vector processor. The instruction control mechanism is designed to enhance the performance of the scalar/vector processor by keeping a multiplicity of pipelines substantially filled with a minimum number of gaps.

Abstract: A global register system provides communication and coordination among a plurality of processors sharing a common memory in a multiprocessor system which access one or more registers within a shared resource circuit that is separate from the common memory and is symmetrically accessible by the plurality of processors in the multiprocessor system. The global register system is accessed by direct addresses determined by the processor from a previously assigned indirect address and an instruction accessing the data stored in global registers. Arithmetic or logic operation on a data value stored in a selected one of the registers are performed by the global register system independent from the processors or the common memory in order to modify the data value in the selected global register as part of an atomic operation performed in response to a single read-and-modify instruction received from one of the processors.

Abstract: The present invention is an improved high performance scalar/vector processor. In the preferred embodiment, the scalar/vector processor is used in a multiprocessor system. The scalar/vector processor is comprised of a scalar processor for operating on scalar and logical instructions, including a plurality of independent functional units operably connected to the scalar processor, a vector processor for operating on vector instructions, including a plurality of independent functional units operably connected to the vector processor, and an instruction control mechanism for fetching both the scalar and vector instructions from an instruction cache and controlling the operation of those instructions in both the scalar and vector processor. The instruction control mechanism is designed to enhance the performance of the scalar/vector processor by keeping a multiplicity of pipelines substantially filled with a minimum number of gaps.

Abstract: A unified parallel processing architecture connects together an extendible number of clusters of multiple numbers of processors to create a high performance parallel processing computer system. Multiple processors are grouped together into four or more physically separable clusters, each cluster having a common cluster shared memory that is symmetrically accessible by all of the processors in that cluster; however, only some of the clusters are adjacently interconnected. Clusters are adjacently interconnected to form a floating shared memory if certain memory access conditions relating to relative memory latency and relative data locality can create an effective shared memory parallel programming environment. A shared memory model can be used with programs that can be executed in the cluster shared memory of a single cluster, or in the floating shared memory that is defined across an extended shared memory space comprised of the cluster shared memories of any set of adjacently interconnected clusters.

Abstract: Methods and apparatus for a maintenance and control system for sensing and controlling the numerous sections of a highly parallel multiprocessor system. The control and maintenance system communicates with all processors, all peripheral systems, all user interfaces to the multiprocessor system, a system console, and the power and environmental control subsystems.

Abstract: A signaling mechanism for sending and receiving signals to and from any one of all of a plurality of devices, including peripheral controllers and processors, in a multiprocessor system. The signaling mechanism includes two switches, a first switch routing a signal command generated by the device to a signal dispatch logic and a second switch for receiving signals generated by the signal dispatch logic and routing the signals to the selected device. The signal dispatch logic receiving the signal command, decodes the destination select value and generates a signal to be sent to the selected device. The signal command includes a destination select value representing a device selectably determined by the device. The signaling mechanism also includes an arbitration mechanism connected to the signal dispatch logic and the first switch for resolving simultaneous conflicting signal commands issued by two or more devices.

Abstract: A method and apparatus for non-sequential access to shared resources in a multiple requestor system uses a variety of tags to effectively re-order the data at its destination. In simplest form, the tag directs switching logic to where in a buffer to locate another tag for direction information or where in a buffer or processor (register) to put the response associated with the tag. For example, loading data from memory requires that the requestor provide a request signal, an address, and a request tag. The request signal validates the address and request tag. The address specifies the location of the requested data in memory. The request tag specifies where to put the data when it is returned to the processor.

Abstract: A cluster architecture for a highly parallel multiprocessor computer processing system is comprised of one or more clusters of tightly-coupled, high-speed processors capable of both vector and scalar parallel processing that can symmetrically access shared resources associated with the cluster, as well as the shared resources associated with other clusters.

Abstract: A special purpose arithmetic boolean unit is capable of performing extremely parallel bit-level boolean operations, particularly bit matrix manipulations. The special purpose arithmetic boolean unit is especially adapted for use in traditional vector processors, thereby enabling a vector processor to effectively solve extremely parallel MIMD or SIMD boolean problems without requiring an array processor or massively parallel supercomputer.