The invention relates to a method of designing a processor core arrangement which comprises a first processor core for operation at a first operation frequency and having an associated first leakage and a second processor core for operation at a second operation frequency lower than the first operation frequency and having an associated second leakage lower than the associated first leakage. The processor core arrangement is capable of switching from the first processor core to the second processor core and vice versa.

Apparatus and methods are disclosed for controlling execution of memory access instructions in a block-based processor architecture using a hardware structure that indicates a relative ordering of memory access instruction in an instruction block. In one example of the disclosed technology, a method of executing an instruction block having a plurality of memory load and/or memory store instructions includes selecting a next memory load or memory store instruction to execute based on dependencies encoded within the block, and on a store vector that stores data indicating which memory load and memory store instructions in the instruction block have executed. The store vector can be masked using a store mask. The store mask can be generated when decoding the instruction block, or copied from an instruction block header. Based on the encoded dependencies and the masked store vector, the next instruction can issue when its dependencies are available.

An apparatus and method for performing high performance instruction emulation. One embodiment of the invention includes a processor to process an instruction set including high-power and standard instructions comprising: an analysis module to determine whether a number of high-power instructions within a specified window are above or below a specified threshold; an execution mode selection module to select a native execution of the high-power instructions if the number of high-power instructions are above the specified threshold or to select an emulated execution of the high-power instructions if the number of high-power instructions are below the specified threshold.

Embodiments of methods and apparatuses for restricted speculative execution are disclosed. In an embodiment, a processor includes configuration storage, an execution circuit, and a controller. The configuration storage is to store an indicator to enable a restricted speculative execution mode of operation of the processor, wherein the processor is to restrict speculative execution when operating in restricted speculative execution mode. The execution circuit is to perform speculative execution. The controller to restrict speculative execution by the execution circuit when the restricted speculative execution mode is enabled.

Embodiments of the present disclosure support hardware based thread switching in a multithreading environment. The tread switching is implemented on a multithread microprocessor by utilizing thread mailbox registers and other auxiliary registers that can be pre-programmed for hardware based thread switching. A set of mailbox registers can be allocated to each thread of a plurality of threads that can be executed in the microprocessor. A mailbox register in the set of mailbox registers comprises an identifier of a next thread of the plurality of threads to which an active thread switches based on a thread switch condition further indicated in the mailbox register. The auxiliary registers in the microprocessor can be used to configure a number of threads for simultaneous execution in the microprocessor, a priority for thread switching, and to store a program counter of each thread and states of registers of each thread.

An approach is provided for enabling power reduction in floating-point operations. In one example, a system receives floating-point numbers of a fused multiply-add instruction. The system determines the fused multiply-add instruction does not require compliance with a standard of precision for floating-point numbers. The system generates gating signals for an integrated circuit that is configured to perform operations of the fused multiply-add instruction. The system then sends the gating signals to the integrated circuit to turn off a plurality of logic gates included in the integrated circuit.

An enhanced security of multiple software processes executing on a computer system is provided by isolating those processes from each other and from access to system hardware resources. Embodiments provide such isolation by executing kernel software that manages hardware and controls physical address space on a separate hardware thread (e.g., in an isolation domain) from the process threads executing application programs (e.g., in execution domains). This renders the software executing in the isolation domain safe from privilege escalation attacks and permits implementation of enforceable isolation between execution systems. A multithreaded processor having switch-on-event multithreading is used to provide software isolation and hardware-controlled handling of a subset of system services by a different hardware thread than the one requesting the service.

Techniques are provided for data management across a persistent memory tier and a file system tier. A block within a persistent memory tier of a node is determined to have up-to-date data compared to a corresponding block within a file system tier of the node. The corresponding block may be marked as a dirty block within the file system tier. Location information of a location of the block within the persistent memory tier is encoded into a container associated with the corresponding block. In response to receiving a read operation, the location information is obtained from the container. The up-to-date data is retrieved from the block within the persistent memory tier using the location information for processing the read operation.

Disclosed embodiments relate to systems and methods for performing 16-bit floating-point vector dot product instructions. In one example, a processor includes fetch circuitry to fetch an instruction having fields to specify an opcode and locations of first source, second source, and destination vectors, the opcode to indicate execution circuitry is to multiply N pairs of 16-bit floating-point formatted elements of the specified first and second sources, and accumulate the resulting products with previous contents of a corresponding single-precision element of the specified destination, decode circuitry to decode the fetched instruction, and execution circuitry to respond to the decoded instruction as specified by the opcode.

Data processing apparatuses, methods of data processing, and non-transitory computer-readable media on which computer-readable code is stored defining logical configurations of processing devices are disclosed. In an apparatus, fetch circuitry retrieves a sequence of instructions and execution circuitry performs data processing operations with respect to data values in a set of registers. An auxiliary execution circuitry interface and a coprocessor interface to provide a connection to a coprocessor outside the apparatus are provided. Decoding circuitry generates control signals in dependence on the instructions of the sequence of instructions, wherein the decoding circuitry is responsive to instructions in a first subset of an instruction encoding space to generate the control signals to control the execution circuitry to perform the first data processing operations, and the decoding circuitry is responsive to instructions in a second subset of the instruction encoding space to generate the control signals in dependence on a configuration condition: to generate the control signals for the auxiliary execution circuitry interface when the configuration condition has a first state; and to generate the control signals for the coprocessor interface when the configuration condition has a second state.