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 for the nested loops. A steam head register stores data elements next to be supplied to functional units for use as operands. A stream template specifies loop count and loop dimension for each nested loop. A format definition field in the stream template specifies the number of loops and the stream template bits devoted to the loop counts and loop dimensions. This permits the same bits of the stream template to be interpreted differently enabling trade off between the number of loops supported and the size of the loop counts and loop dimensions.

In various examples, a VPU and associated components may be optimized to improve VPU performance and throughput. For example, the VPU may include a min/max collector, automatic store predication functionality, a SIMD data path organization that allows for inter-lane sharing, a transposed load/store with stride parameter functionality, a load with permute and zero insertion functionality, hardware, logic, and memory layout functionality to allow for two point and two by two point lookups, and per memory bank load caching capabilities. In addition, decoupled accelerators may be used to offload VPU processing tasks to increase throughput and performance, and a hardware sequencer may be included in a DMA system to reduce programming complexity of the VPU and the DMA system. The DMA and VPU may execute a VPU configuration mode that allows the VPU and DMA to operate without a processing controller for performing dynamic region based data movement operations.

In various examples, a VPU and associated components may be optimized to improve VPU performance and throughput. For example, the VPU may include a min/max collector, automatic store predication functionality, a SIMD data path organization that allows for inter-lane sharing, a transposed load/store with stride parameter functionality, a load with permute and zero insertion functionality, hardware, logic, and memory layout functionality to allow for two point and two by two point lookups, and per memory bank load caching capabilities. In addition, decoupled accelerators may be used to offload VPU processing tasks to increase throughput and performance, and a hardware sequencer may be included in a DMA system to reduce programming complexity of the VPU and the DMA system. The DMA and VPU may execute a VPU configuration mode that allows the VPU and DMA to operate without a processing controller for performing dynamic region based data movement operations.

A method includes receiving, for metadata processing, a current instruction with associated metadata tags. The metadata processing is performed in a metadata processing domain isolated from a code execution domain including the current instruction. Each respective associated metadata tag represents a respective policy of the composite policy. For each respective metadata tag, the method includes determining, in the metadata processing domain and in accordance with the metadata tag and the current instruction, whether a rule exists for the current instruction in a rules cache. The rules cache may include rules on metadata used by the metadata processing to define allowed instructions. The determination of whether a rule exists results in a respective output, which may include generating a new rule and inserting the new rule in the rules cache. Control Status Registers, and associated tags, may be used to accomplish the metadata processing.

A method for executing an atomic compare and exchange operation, the method may include processing a compare command and a conditional exchange command while considering hardware failures.

A predicated-loop-terminating branch instruction controls, based on whether a loop termination condition is satisfied, whether the processing circuitry should process a further iteration of a predicated loop body or process a following instruction. If at least one unnecessary iteration of the predicated loop body is processed following a mispredicted-non-termination branch misprediction when the loop termination condition is mispredicted as unsatisfied for a given iteration when it should have been satisfied, processing of the at least one unnecessary iteration of the predicated loop body is predicated to suppress an effect of the at least one unnecessary iteration. When the mispredicted-non-termination branch misprediction is detected for the given iteration of the predicated-loop-terminating branch instruction, in response to determining that a flush suppressing condition is satisfied, flushing of the at least one unnecessary iteration of the predicated loop body is suppressed as a response to the mispredicted-non-termination branch misprediction.

In one embodiment of the present invention, a programmable vision accelerator enables applications to collapse multi-dimensional loops into one dimensional loops. In general, configurable components included in the programmable vision accelerator work together to facilitate such loop collapsing. The configurable elements include multi-dimensional address generators, vector units, and load/store units. Each multi-dimensional address generator generates a different address pattern. Each address pattern represents an overall addressing sequence associated with an object accessed within the collapsed loop. The vector units and the load store units provide execution functionality typically associated with multi-dimensional loops based on the address pattern. Advantageously, collapsing multi-dimensional loops in a flexible manner dramatically reduces the overhead associated with implementing a wide range of computer vision algorithms. Consequently, the overall performance of many computer vision applications may be optimized.

A head-mounted device includes a mounted member that is mounted on a head of a user, a sensor unit, which is a detection device, that detects a posture of the mounted member, a control device that switches a control mode according to the posture detected in the sensor unit, and a video output device and an audio output device as output devices that perform output operations according to the control mode in the control device.

In one disclosed embodiment, a processor includes a first execution unit and a second execution unit, a register file, and a data path including a plurality of lanes. The data path and the register file are arranged so that writing to the register file by the first execution unit and by the second execution unit is allowed over the data path, reading from the register file by the first execution unit is allowed over the data path, and reading from the register file by the second execution unit is not allowed over the data path. The processor also includes a power control circuit configured to, when a transfer of data between the register file and either of the first and second execution units uses less than all of the lanes, power down the lanes of the data path not used for the transfer of the data.

A predicated vector load micro-operation specifies a load target address, a destination vector register for which active vector elements of the destination vector register are to be loaded with data associated with addresses identified based on the load target address, and a predicate operand indicative of whether each vector element of the destination vector register is active or inactive. A predetermined type of predicated vector load micro-operation can be issued to the processing circuitry before the predicate operand is determined to meet an availability condition, and if issued in this way memory access circuitry can determine, based on the load target address, whether the predetermined type of predicated vector load micro-operation satisfies a predetermined condition, and if the predetermined condition is unsatisfied, perform a complete vector load assuming all vector elements of the destination vector register are active vector elements, independent of whether the predicate operand when available identifies any inactive vector element of the destination vector register.