Abstract: The present invention provides extended precision in SIMD arithmetic operations in a processor having a register file and an accumulator. A first set of data elements and a second set of data elements are loaded into a first vector register and a second vector register, respectively. Each data element comprises N bits. Next, an arithmetic instruction is fetched from memory. The arithmetic instruction is decoded. Then, a first vector register and a second vector register are read from the register file. The present invention then executes the arithmetic instruction on corresponding data elements in the first and second vector registers. The result of the execution is then written into the accumulator. Then, each element in the accumulator is transformed into an N-bit width element and stored into the memory.

Abstract: An automated processor design tool uses a description of customized processor instruction set extensions in a standardized language to develop a configurable definition of a target instruction set, a Hardware Description Language description of circuitry necessary to implement the instruction set, and development tools such as a compiler, assembler, debugger and simulator which can be used to develop applications for the processor and to verify it. Implementation of the processor circuitry can be optimized for various criteria such as area, power consumption, speed and the like. Once a processor configuration is developed, it can be tested and inputs to the system modified to iteratively optimize the processor implementation. By providing a constrained domain of extensions and optimizations, the process can be automated to a high degree, thereby facilitating fast and reliable development.

Abstract: The present invention provides extended precision in SIMD arithmetic operations in a processor having a register file and an accumulator. A first set of data elements and a second set of data elements are loaded into first and second vector registers, respectively. Each data element comprises N bits. Next, an arithmetic instruction is fetched from memory. The arithmetic instruction is decoded. Then, the first vector register and the second vector register are read from the register file. The present invention executes the arithmetic instruction on corresponding data elements in the first and second vector registers. The resulting element of the execution is then written into the accumulator. Then, the resulting element is transformed into an N-bit width element and written into a third register for further operation or storage in memory. The transformation of the resulting element can include, for example, rounding, clamping, and/or shifting the element.

Abstract: A system for generating processor hardware supports a language for significant extensions to the processor instruction set, where the designer specifies only the semantics of the new instructions and the system generates other logic. The extension language provides for the addition of processor state, including register files, and instructions that operate on that state. The language also provides for new data types to be added to the compiler to represent the state added. It allows separate specification of reference semantics and instruction implementation, and uses this to automate design verification. In addition, the system generates formatted instruction set documentation from the language specification.

Abstract: A system for generating processor hardware supports a language for significant extensions to the processor instruction set, where the designer specifies only the semantics of the new instructions and the system generates other logic. The extension language provides for the addition of processor state, including register files, and instructions that operate on that state. The language also provides for new data types to be added to the compiler to represent the state added. It allows separate specification of reference semantics and instruction implementation, and uses this to automate design verification. In addition, the system generates formatted instruction set documentation from the language specification.

Abstract: An automated processor design tool uses a description of customized processor instruction set extensions in a standardized language to develop a configurable definition of a target instruction set, a Hardware Description Language description of circuitry necessary to implement the instruction set, and development tools such as a compiler, assembler, debugger and simulator which can be used to develop applications for the processor and to verify it. Implementation of the processor circuitry can be optimized for various criteria such as area, power consumption, speed and the like. Once a processor configuration is developed, it can be tested and inputs to the system modified to iteratively optimize the processor implementation. By providing a constrained domain of extensions and optimizations, the process can be automated to a high degree, thereby facilitating fast and reliable development.

Abstract: A system for adding advanced instructions to a microprocessor includes a language for formally capturing the new instructions and a method for generating hardware implementations and software tools for the extended processors. The extension language provides for additions of VLIW instructions, complex load/store instructions, more powerful description styles using functions, more powerful register operands, and a new set of built-in modules. The method is capable of generating fully-pipelined micro-architectural implementations for the new instructions in the form of synthesizable HDL descriptions which can be processed by standard CAD tools. The method is also capable of generating software components for extending software development tools for the microprocessor with new instructions.

Abstract: An MMU provides services at a cost more directly proportional to the needs of the system. According to one aspect, the MMU provides both address translation and sophisticated protection capabilities. Translation and protection are desirable when applications running on the processor are not completely debugged or trustable, for example. According to another aspect, a system for configuring the MMU design according to user specifications and system needs is provided. The MMU configurability aspects enable the system designer to configure MMUs having run-time programmability features that span the range from completely static to completely dynamic. In addition, the MMU can be configured to support variable page sizes, multiple protection and sharing rings, demand paging, and hardware TLB refill, for example.

Abstract: An automated processor design tool uses a description of customized processor instruction set extensions in a standardized language to develop a configurable definition of a target instruction set, a Hardware Description Language description of circuitry necessary to implement the instruction set, and development tools such as a compiler, assembler, debugger and simulator which can be used to develop applications for the processor and to verify it. Implementation of the processor circuitry can be optimized for various criteria such as area, power consumption, speed and the like. Once a processor configuration is developed, it can be tested and inputs to the system modified to iteratively optimize the processor implementation. By providing a constrained domain of extensions and optimizations, the process can be automated to a high degree, thereby facilitating fast and reliable development.

Abstract: An automated processor design tool uses a description of customized processor instruction set extensions in a standardized language to develop a configurable definition of a target instruction set, a Hardware Description Language description of circuitry necessary to implement the instruction set, and development tools such as a compiler, assembler, debugger and simulator which can be used to develop applications for the processor and to verify it. Implementation of the processor circuitry can be optimized for various criteria such as area, power consumption, speed and the like. Once a processor configuration is developed, it can be tested and inputs to the system modified to iteratively optimize the processor implementation. By providing a constrained domain of extensions and optimizations, the process can be automated to a high degree, thereby facilitating fast and reliable development.

Abstract: An automated processor design tool uses a description of customized processor instruction set extensions in a standardized language to develop a configurable definition of a target instruction set, a Hardware Description Language description of circuitry necessary to implement the instruction set, and development tools such as a compiler, assembler, debugger and simulator which can be used to develop applications for the processor and to verify it. Implementation of the processor circuitry can be optimized for various criteria such as area, power consumption, speed and the like. Once a processor configuration is developed, it can be tested and inputs to the system modified to iteratively optimize the processor implementation. By providing a constrained domain of extensions and optimizations, the process can be automated to a high degree, thereby facilitating fast and reliable development.

Abstract: An automated processor design tool uses a description of customized processor instruction set extensions in a standardized language to develop a configurable definition of a target instruction set, a Hardware Description Language description of circuitry necessary to implement the instruction set, and development tools such as a compiler, assembler, debugger and simulator which can be used to develop applications for the processor and to verify it. Implementation of the processor circuitry can be optimized for various criteria such as area, power consumption, speed and the like. Once a processor configuration is developed, it can be tested and inputs to the system modified to iteratively optimize the processor implementation. By providing a constrained domain of extensions and optimizations, the process can be automated to a high degree, thereby facilitating fast and reliable development.

Abstract: An automated processor design tool uses a description of customized processor instruction set extensions in a standardized language to develop a configurable definition of a target instruction set, a Hardware Description Language description of circuitry necessary to implement the instruction set, and development tools such as a compiler, assembler, debugger and simulator which can be used to develop applications for the processor and to verify it. The standardized language is capable of handling instruction set extensions which modify processor state or use configurable processors. By providing a constrained domain of extensions and optimizations, the process can be automated to a high degree, thereby facilitating fast and reliable development.

Abstract: Instruction prediction based upon confidence and priority levels. A filtering effect is achieved by providing for prediction of an instruction by one of a plurality of predictors having (1) a confidence level satisfying a predetermined threshold value and (2) the highest priority level among the plurality of predictors. A default predictor is provided should no predictor satisfy this criteria. Efficient use of predictor memory is achieved through selective updating of predictors.

Abstract: The present invention provides extended precision in SIMD arithmetic operations in a processor having a register file and an accumulator. A first set of data elements and a second set of data elements are loaded into a first vector register and a second vector register, respectively. Each data element comprises N bits. Next, an arithmetic instruction is fetched from memory. The arithmetic instruction is decoded. Then, a first vector register and a second vector register are read from the register file. The present invention then executes the arithmetic instruction on corresponding data elements in the first and second vector registers. The result of the execution is then written into the accumulator. Then, each element in the accumulator is transformed into an N-bit width element and stored into the memory.

Abstract: A RISC processor implements an instruction set which, in addition to optimizing a relationship between the number of instructions required for execution of a program, clock period and average number of clocks per instruction, also is designed to optimize the equation S=IS * BI, where S is the size of program instructions in bits, IS is the static number of instructions required to represent the program (not the number required by an execution) and BI is the average number of bits per instruction. Compared to conventional RISC architectures, this processor lowers both BI and IS with minimal increases in clock period and average number of clocks per instruction. The processor provides good code density in a fixed-length high-performance encoding based on RISC principles, including a general register with load/store architecture. Further, the processor implements a simple variable-length encoding that maintains high performance.

Abstract: The present invention provides alignment and ordering of vector elements for SIMD processing. In the alignment of vector elements for SIMD processing, one vector is loaded from a memory unit into a first register and another vector is loaded from the memory unit into a second register. The first vector contains a first byte of an aligned vector to be generated. Then, a starting byte specifying the first byte of an aligned vector is determined. Next, a vector is extracted from the first register and the second register beginning from the first bit in the first byte of the first register continuing through the bits in the second register. Finally, the extracted vector is replicated into a third register such that the third register contains a plurality of elements aligned for SIMD processing. In the ordering of vector elements for SIMD processing, a first vector is loaded from a memory unit into a first register and a second vector is loaded from the memory unit into a second register.

Abstract: Instruction prediction based upon confidence and priority levels. A filtering effect is achieved by providing for prediction of an instruction by one of a plurality of predictors having (1) a confidence level satisfying a predetermined threshold value and (2) the highest priority level among the plurality of predictors. A default predictor is provided should no predictor satisfy this criteria. Efficient use of predictor memory is achieved through selective updating of predictors.

Abstract: The present invention provides alignment and ordering of vector elements for SIMD processing. In the alignment of vector elements for SIMD processing, one vector is loaded from a memory unit into a first register and another vector is loaded from the memory unit into a second register. The first vector contains a first byte of an aligned vector to be generated. Then, a starting byte specifying the first byte of an aligned vector is determined. Next, a vector is extracted from the first register and the second register beginning from the first bit in the first byte of the first register continuing through the bits in the second register. Finally, the extracted vector is replicated into a third register such that the third register contains a plurality of elements aligned for SIMD processing. In the ordering of vector elements for SIMD processing, a first vector is loaded from a memory unit into a first register and a second vector is loaded from the memory unit into a second register.

Abstract: The present invention provides extended precision in SIMD arithmetic operations in a processor having a register file and an accumulator. A first set of data elements and a second set of data elements are loaded into a first vector register and a second vector register, respectively. Each data element comprises N bits. Next, an arithmetic instruction is fetched from memory. The arithmetic instruction is decoded. Then, a first vector register and a second vector register are read from the register file. The present invention then executes the arithmetic instruction on corresponding data elements in the first and second vector registers. The result of the execution is then written into the accumulator. Then, each element in the accumulator is transformed into an N-bit width element and stored into the memory.