Abstract:
In an embodiment, a processor includes a plurality of cores, with at least one core including a cancellation monitor unit. The cancellation monitor unit comprises circuitry to: detect an execution of a floating point (FP) instruction in the core, wherein the execution of the FP instruction uses a set of FP inputs and generates an FP output; determine a maximum exponent value associated with the set of FP inputs to the FP instruction; subtract an exponent value of the FP output from the maximum exponent value to obtain an exponent difference; and in response to a determination that the exponent difference meets or exceeds a threshold level, increment a cancellation event count. Other embodiments are described and claimed.
Abstract:
A data processing system supports vector operands on a plurality of elements each representing different bit portions of a single integer number. Processing circuitry performs a processing operation specified by a program instruction in dependence upon a number of elements comprising the bit portions as specified by metadata for the vector.
Abstract:
An apparatus comprises processing circuitry to perform a conversion operation to convert a floating-point value to a vector comprising a plurality of data elements representing respective bit significance portions of a two's complement format fixed point value corresponding to the sign-magnitude format floating-point value.
Abstract:
Apparatus performs various modal interval computations, while accounting for various modal interval operand configurations that are not amenable to ordinary computational operations. Upon detecting an exponent field of all 1's, the apparatus adapts various conventions involving leading bits in the fraction field of the modal interval endpoints to return a result having a useful meaning.
Abstract:
A microprocessor (10) comprises at least one general-purpose-register (12) arranged to store and provide a number of destination bits to a multiply unit (14); a control unit (18) adapted to provide at least a multiply-high instruction (20) and a multiply-high- and- accumulate instruction (22) to the multiply unit. The multiply unit is further arranged to receive at least a first and a second source operand (24, 26), each having an associated number of source bits and a sum of the associated numbers of source bits exceeding the number of destination bits, connected to a register-extension cache (28) comprising at least one cache entry arranged to store and provide a number of precision-enhancement bits, and adapted to store a destination portion of a result operand in the general-purpose- register and a precision-enhancement portion of the result operand in the cache entry. The result operand is generated by a multiply-high operation when or by a multiply-high-and-accumulate operation depending on the recieved instruction.
Abstract:
A processor includes circuitry to decode at least one instruction and an execution unit. The decoded instruction may compute a floating point result. The execution unit includes circuitry to execute the instruction to determine the floating point result, compute the amount of precision lost in a mantissa of the floating point result, compare the amount of precision lost to a numeric accumulation error precision threshold, determine whether a numeric accumulation error occurred based on the comparison, and write a value to a flag. The amount of precision lost corresponds to a plurality of bits lost in the mantissa of the floating point result. The value to be written to the flag may be based on the determination that the numeric accumulation error occurred. The flag may be for notification that the numeric accumulation error occurred.
Abstract:
An apparatus and method are provided for processing floating point values using an intermediate representation which has significand, exponent and shadow sections. A less significant portion of the exponent of the floating point value defines a range of positions within the significand section where the representation of the significand is to be held. The exponent section holds a representation of a more significant portion of the exponent indicating a selected window of multiple contiguous windows spanning a value range of a format of the floating point value. A first portion of the significand section corresponds to the selected window and a second portion corresponds to an overlap into a further window which is adjacent to and lower in the value range. The shadow section holds values for populating the second portion of the significand section when the representation of the significand of the floating point value is moved to a higher window which is adjacent to and higher in the value range than the selected window. The shadow section allows the selected window to be shifted, such that the summation of multiple values produces the same result independent of the order in which the values are summed.
Abstract:
A data processing system uses alignment circuitry to align input operands in accordance with a programmable significance parameter to form aligned input operands. The aligned input operands are supplied to arithmetic circuitry, such as an integer adder or an integer multiplier, where a result value is formed. The result value is stored in an output operand storage element, such as a result register. The programmable significance parameter is independent of the result value.
Abstract:
An apparatus comprises processing circuitry for performing, in response to a vector instruction, a plurality of lanes of processing or respective data elements with at least one operand vector to generate corresponding result data elements of a result vector. The processing circuitry may support performing at least two of the lanes of processing with different rounding modes for generating rounding values for the corresponding result data elements of the result vector. This allows two or more calculations with different rounding modes to be executed in response to a single instruction, to improve performance.