A method is provided that includes receiving, in a permute network, a plurality of data elements for a vector instruction from a streaming engine, and mapping, by the permute network, the plurality of data elements to vector locations for execution of the vector instruction by a vector functional unit in a vector data path of a processor.

Methods and apparatus for a low energy accelerator processor architecture with short parallel instruction word. An integrated circuit includes a system bus having a data width N, where N is a positive integer; a central processor unit coupled to the system bus and configured to execute instructions retrieved from a memory coupled to the system bus; and a low energy accelerator processor coupled to the system bus and configured to execute instruction words retrieved from a low energy accelerator code memory, the low energy accelerator processor having a plurality of execution units including a load store unit, a load coefficient unit, a multiply unit, and a butterfly/adder ALU unit, each of the execution units configured to perform operations responsive to op-codes decoded from the retrieved instruction words, wherein the width of the instruction words is equal to the data width N. Additional methods and apparatus are disclosed.

Software instructions are executed on a processor within a computer system to configure a steaming engine with stream parameters to define a multidimensional array. The stream parameters define a size for each dimension of the multidimensional array and a specified width for two selected dimensions of the array. Data is fetched from a memory coupled to the streaming engine responsive to the stream parameters. A stream of vectors is formed for the multidimensional array responsive to the stream parameters from the data fetched from memory. When either selected dimension in the stream of vectors exceeds a respective specified width, the streaming engine inserts null elements into each portion of a respective vector for the selected dimension that exceeds the specified width in the stream of vectors. Stream vectors that are completely null are formed by the streaming engine without accessing the system memory for respective data.

A chaining bit decoder of a computer processor receives an instruction stream. The chaining bit decoder selects a group of instructions from the instruction stream. The chaining bit decoder extracts a designated bit from each instruction of the instruction stream to produce a sequence of chaining bits. The chaining bit decoder decodes the sequence of chaining bits. The chaining bit decoder identifies zero or more instruction stream dependencies among the selected group of instructions in view of the decoded sequence of chaining bits. The chaining bit decoder outputs control signals to cause one or more pipelines stages of the processor to execute the selected group of instructions in view of the identified zero or more instruction stream dependencies among the group sequence of instructions.

A computing device determines that a current software thread of a plurality of software threads having an issuing sequence does not have a first instruction waiting to be issued to a hardware thread during a clock cycle. The computing device identifies one or more alternative software threads in the issuing sequence having instructions waiting to be issued. The computing device selects, during the clock cycle by the computing device, a second instruction from a second software thread among the one or more alternative software threads in view of determining that the second instruction has no dependencies with any other instructions among the instructions waiting to be issued. Dependencies are identified by the computing device in view of the values of a chaining bit extracted from each of the instructions waiting to be issued. The computing device issues the second instruction to the hardware thread.

A microprocessor is shown, in which a branch predictor and an instruction cache are decoupled by a fetch-target queue (FTQ). The FTQ stores at least an instruction address whose branch prediction has been finished by the branch predictor. The instruction addresses queued in the FTQ is to be read out later as an instruction-fetching address for the instruction cache. The instruction address that is input into the branch predictor and used for branch prediction leads the instruction-fetching address.

In one embodiment, a system includes a memory and a processor core. The processor core includes functional units and an instruction decode unit configured to determine whether an execute packet of instructions received by the processing core includes a first instruction that is designated for execution by a first functional unit of the functional units and a second instruction that is a condition code extension instruction that includes a plurality of sets of condition code bits, wherein each set of condition code bits corresponds to a different one of the functional units, and wherein the sets of condition code bits include a first set of condition code bits that corresponds to the first functional unit. When the execute packet includes the first and second instructions, the first functional unit is configured to execute the first instruction conditionally based upon the first set of condition code bits in the second instruction.

A stream of data is accessed from a memory system using a stream of addresses generated in a first mode of operating a streaming engine in response to executing a first stream instruction. A block cache management operation is performed on a cache in the memory using a block of addresses generated in a second mode of operating the streaming engine in response to executing a second stream instruction.

Techniques related to executing instructions by a processor comprising receiving a first instruction for execution, determining a first latency value based on an expected amount of time needed for the first instruction to be executed, storing the first latency value in a writeback queue, beginning execution of the first instruction on the instruction execution pipeline, adjusting the latency value based on an amount of time passed since beginning execution of the first instruction, outputting a first result of the first instruction based on the latency value, receiving a second instruction, determining that the second instruction is a variable latency instruction, storing a ready value indicating that a second result of the second instruction is not ready in the writeback queue, beginning execution of the second instruction on the instruction execution pipeline, updating the ready value to indicate that the second result is ready, and outputting the second result.

A streaming engine employed in a digital data processor specifies a fixed read only data stream defined by plural nested loops. An address generator produces address of data elements. A steam head register stores data elements next to be supplied to functional units for use as operands. An element duplication unit optionally duplicates data element an instruction specified number of times. A vector masking unit limits data elements received from the element duplication unit to least significant bits within an instruction specified vector length. If the vector length is less than a stream head register size, the vector masking unit stores all 0's in excess lanes of the stream head register (group duplication disabled) or stores duplicate copies of the least significant bits in excess lanes of the stream head register.