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: In a binary floating point processor, the exponents of each of the various types of operands are recoded into an internal format, by biasing the exponents with the minimum exponent value of the result precision (“Emin”), i.e., the recoded value of the exponent is the represented value of the exponent minus Emin. Emin depends only on the result precision of the instruction that is currently being executed in the binary floating point processor. The exponent computations are then performed in this new format. The underflow check for all result precisions is a check against zero and overflow checks are performed against a positive number that depends on the result precision. The exponent values are in a 2's complement representation, so the underflow check simply becomes a check of the sign bit.

Abstract: A method, system and computer program product 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: A floating point processor unit includes a shift amount calculation circuit within a normalizer portion of the floating point unit, wherein the shift amount calculation circuit is utilized to compute the normalizer shift amount for a log estimate instruction that runs as a pipelinable 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: 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: Various systems and processes may be used to speed up multi-threaded execution. In certain implementations, a system and process may include the ability to write results of a first group of execution units associated with a first register file into the first register file using a first write port of the first register file and write results of a second group of execution units associated with a second register file into the second register file using a first write port of the second register file. The system, apparatus, and process may also include the ability to connect, in a shared register file mode, results of the second group of execution units to a second write port of the first register file and connect, in a split register file mode, results of a part of the first group of execution units to the second write port of the first register file.

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: A floating point processor unit includes a shift amount calculation circuit within a normalizer portion of the floating point unit, wherein the shift amount calculation circuit is utilized to compute the normalizer shift amount for a log estimate instruction that runs as a pipelinable instruction.

Abstract: In a binary floating point processor, the exponents of each of the various types of operands are recoded into an internal format, by biasing the exponents with the minimum exponent value of the result precision (“Emin”), i.e., the recoded value of the exponent is the represented value of the exponent minus Emin. Emin depends only on the result precision of the instruction that is currently being executed in the binary floating point processor. The exponent computations are then performed in this new format. The underflow check for all result precisions is a check against zero and overflow checks are performed against a positive number that depends on the result precision. The exponent values are in a 2's complement representation, so the underflow check simply becomes a check of the sign bit.

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.

Abstract: A method, system and computer program product 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.