Abstract: Various systems, apparatuses, processes, and/or products may be used to calculate an SHA-2 hash function in a general-purpose processor. In some implementations, a system, apparatus, process, and/or product may include the ability to calculate at least one SHA-2 sigma function by using an execution unit adapted for performing a processor instruction, the execution unit including an integrated circuit primarily designed for calculating the SHA-2 sigma function(s), and calculating the SHA-2 hash function with general-purpose hardware processing components of the processor based on the sigma function(s). In certain implementations, the calculation of the SHA-2 sigma function(s) can be performed by the integrated circuit within a single instruction, allowing for a faster calculation of the SHA-2 hash function.

Abstract: A fused multiply-adder is disclosed. The fused multiply-adder includes a Booth encoder, a fraction multiplier, a carry corrector, and an adder. The Booth encoder initially encodes a first operand. The fraction multiplier multiplies the Booth-encoded first operand by a second operand to produce partial products, and then reduces the partial products into a set of redundant sum and carry vectors. The carry corrector then generates a carry correction factor for correcting the carry vectors. The adder adds the redundant sum and carry vectors and the carry correction factor to a third operand to yield a final result.

Abstract: A list of input registers and output registers for a circuit design are provided. The circuit design is modified by traversing output connections paths for each input register and replacing any register in the output connection paths with a wire unless the register is a listed output register. An initial total cycle time value for the modified circuit design is determined. A gate level description for the modified circuit design is obtained by a macro synthesis with the initial total cycle time value. The total cycle time value for the modified circuit design is then varied in order to determine the theoretical limit of the modified circuit design. This theoretical limit is realized when negative slacks are present in a macro synthesis of the modified circuit design for a given total cycle time value. Based on this theoretical limit, the minimum pipeline depth of the circuit design is determined.

Abstract: A hardware circuit for returning single precision denormal results to double precision. A hardware circuit component configured to count leading zeros of an unrounded single precision denormal result. A hardware circuit component configured to pre-compute a first exponent and a second exponent for the unrounded single precision denormal result. A hardware circuit component configured to perform a second normalization of the rounded single precision denormal result back to architected format.

Abstract: A hardware circuit for returning single precision denormal results to double precision. A hardware circuit component configured to count leading zeros of an unrounded single precision denormal result. A hardware circuit component configured to pre-compute a first exponent and a second exponent for the unrounded single precision denormal result. A hardware circuit component configured to perform a second normalization of the rounded single precision denormal result back to architected format.

Abstract: Techniques for reducing issue-to-issue latency by reversing processing order in half-pumped single instruction multiple data (SIMD) execution units are described. In one embodiment a processor functional unit is provided comprising a frontend unit, and execution core unit, a backend unit, an execution order control signal unit, a first interconnect coupled between and output and an input of the execution core unit and a second interconnect coupled between an output of the backend unit and an input of the frontend unit. In operation, the execution order control signal unit generates a forwarding order control signal based on the parity of an applied clock signal on reception of a first vector instruction. This control signal is in turn used to selectively forward first and second portions of an execution result of the first vector instruction via the interconnects for use in the execution of a dependent second vector instruction.

Abstract: A hardware circuit component configured to support vector operations in a scalar data path. The hardware circuit component configured to operate in a vector mode configuration and in a scalar mode configuration. The hardware circuit component configured to split the scalar mode configuration into a left half and a right half of the vector mode configuration. The hardware circuit component configured to perform one or more bit shifts over one or more stages of interconnected multiplexers in the vector mode configuration. The hardware circuit component configured to include duplicated coarse shift multiplexers at bit positions that receive data from both the left half and the right half of the vector mode configuration, resulting in one or more coarse shift multiplexers sharing the bit position.

Abstract: A hardware circuit component configured to support vector operations in a scalar data path. The hardware circuit component configured to operate in a vector mode configuration and in a scalar mode configuration. The hardware circuit component configured to split the scalar mode configuration into a left half and a right half of the vector mode configuration. The hardware circuit component configured to perform one or more bit shifts over one or more stages of interconnected multiplexers in the vector mode configuration. The hardware circuit component configured to include duplicated coarse shift multiplexers at bit positions that receive data from both the left half and the right half of the vector mode configuration, resulting in one or more coarse shift multiplexers sharing the bit position.

Abstract: Techniques for reducing issue-to-issue latency by reversing processing order in half-pumped single instruction multiple data (SIMD) execution units are described. In one embodiment a processor functional unit is provided comprising a frontend unit, and execution core unit, a backend unit, an execution order control signal unit, a first interconnect coupled between and output and an input of the execution core unit and a second interconnect coupled between an output of the backend unit and an input of the frontend unit. In operation, the execution order control signal unit generates a forwarding order control signal based on the parity of an applied clock signal on reception of a first vector instruction. This control signal is in turn used to selectively forward first and second portions of an execution result of the first vector instruction via the interconnects for use in the execution of a dependent second vector instruction.

Abstract: Various systems, apparatuses, processes, and programs may be used to calculate a multiply-sum of two carry-less multiplications of two input operands. In particular implementations, a system, apparatus, process, and program may include the ability to use input data busses for the input operands and an output data bus for an overall calculation result, each bus including a width of 2n bits, where n is an integer greater than one. The system, apparatus, process, and program may also calculate the carry-less multiplications of the two input operands for a lower level of a hierarchical structure and calculating the at least one multiply-sum and at least one intermediate multiply-sum for a higher level of the structure based on the carry-less multiplications of the lower level. A certain number of multiply-sums may be output as an overall calculation result dependent on mode of operation using the full width of said output data bus.

Abstract: A method for verification of a vector execution unit design. The method includes issuing an instruction into a first instance and a second instance of a vector execution unit. The method includes issuing a random operand into a first lane of the first instance of the vector execution unit and into a second lane of the second instance of the vector execution unit. The method further includes receiving results from execution of the instruction and the random operand in both the first and the second instance of the vector execution unit and comparing the received results.

Abstract: A method for verification of a vector execution unit design. The method includes issuing an instruction into a first instance and a second instance of a vector execution unit. The method includes issuing a random operand into a first lane of the first instance of the vector execution unit and into a second lane of the second instance of the vector execution unit. The method further includes receiving results from execution of the instruction and the random operand in both the first and the second instance of the vector execution unit and comparing the received results.

Abstract: A fused multiply-adder is disclosed. The fused multiply-adder includes a Booth encoder, a fraction multiplier, a carry corrector, and an adder. The Booth encoder initially encodes a first operand. The fraction multiplier multiplies the Booth-encoded first operand by a second operand to produce partial products, and then reduces the partial products into a set of redundant sum and carry vectors. The carry corrector then generates a carry correction factor for correcting the carry vectors. The adder adds the redundant sum and carry vectors and the carry correction factor to a third operand to yield a final result.

Abstract: Techniques for reducing issue-to-issue latency by reversing processing order in half-pumped single instruction multiple data (SIMD) execution units are described. In one embodiment a processor functional unit is provided comprising a frontend unit, and execution core unit, a backend unit, an execution order control signal unit, a first interconnect coupled between and output and an input of the execution core unit and a second interconnect coupled between an output of the backend unit and an input of the frontend unit. In operation, the execution order control signal unit generates a forwarding order control signal based on the parity of an applied clock signal on reception of a first vector instruction. This control signal is in turn used to selectively forward first and second portions of an execution result of the first vector instruction via the interconnects for use in the execution of a dependent second vector instruction.

Abstract: A method detects active power dissipation in an integrated circuit. The method includes receiving a hardware design for the integrated circuit having one or more clock domains, wherein the hardware design comprises a local clock buffer for a clock domain, wherein the local clock buffer is configured to receive a clock signal and an actuation signal. The method includes adding instrumentation logic to the design for the clock domain, wherein the instrumentation logic is configured to compare a first value of the actuation signal determined at a beginning point of a test period to a second value of the actuation signal determined at a time when the clock domain is in an idle condition. The method includes detecting the clock domain includes unintended active power dissipation, in response to the first value of the actuation signal not being equal to the second value of the actuation signal.

Abstract: A fused multiply-adder is disclosed. The fused multiply-adder includes a Booth encoder, a fraction multiplier, a carry corrector, and an adder. The Booth encoder initially encodes a first operand. The fraction multiplier multiplies the Booth-encoded first operand by a second operand to produce partial products, and then reduces the partial products into a set of redundant sum and carry vectors. The carry corrector then generates a carry correction factor for correcting the carry vectors. The adder adds the redundant sum and carry vectors and the carry correction factor to a third operand to yield a final result.

Abstract: A method and system for reducing power consumption when processing mathematical operations. Power may be reduced in processor hardware devices that receive one or more operands from an execution unit that executes instructions. A circuit detects when at least one operand of multiple operands is a zero operand, prior to the operand being forwarded to an execution component for completing a mathematical operation. When at least one operand is a zero operand or at least one operand is “unordered”, a flag is set that triggers a gating of a clock signal. The gating of the clock signal disables one or more processing stages and/or devices, which perform the mathematical operation. Disabling the stages and/or devices enables computing the correct result of the mathematical operation on a reduced data path. When a device(s) is disabled, the device may be powered off until the device is again required by subsequent operations.

Abstract: Techniques for reducing issue-to-issue latency by reversing processing order in half-pumped single instruction multiple data (SIMD) execution units are described. In one embodiment a processor functional unit is provided comprising a frontend unit, and execution core unit, a backend unit, an execution order control signal unit, a first interconnect coupled between and output and an input of the execution core unit and a second interconnect coupled between an output of the backend unit and an input of the frontend unit. In operation, the execution order control signal unit generates a forwarding order control signal based on the parity of an applied clock signal on reception of a first vector instruction. This control signal is in turn used to selectively forward first and second portions of an execution result of the first vector instruction via the interconnects for use in the execution of a dependent second vector instruction.

Abstract: A floating point processor unit executes a floating point compare instruction with two operands of the same or different precision by comparing the two operands in integer format, which speeds up the execution of the floating point compare instruction significantly. The floating point processor now executes the floating point compare instruction at least twice as fast or faster (e.g., two clock cycles instead of five clock cycles in the prior art) for nearly most operand cases (e.g., 99% of all cases). Only the rare corner cases require additional operations on one of the operands and thus require additional cycles of execution time because the integer compare operation will not work for these corner cases. This is due to the fact that one operand is a single precision subnormal number in an unnormalized representation (i.e., has two representations) and the other operand is in the SP subnormal range such that the integer compare operation will fail.

Abstract: The forcing of the result or output of a rounder portion of a floating point processor occurs only in a fraction non-increment data path within the rounder and not in the fraction increment data path within the rounder. The fraction forcing is active on a corner case such as a disabled overflow exception. A disabled overflow exception may be detected by inspecting the normalized exponent. If a disabled overflow exception is detected, the round mode is selected to execute only in the non-increment data path thereby preventing the fraction increment data path from being selected.