Abstract: Processing circuitry is provided for comparing a number of adjacent widths having a common value and extending from a starting position within an input number with a runlength specified by a variable number. The circuitry includes a mask generator for generating a mask value in dependence upon the variable number, combination circuitry for performing a logical combination operation upon respective bits within the input number starting from the starting position and corresponding bits within the mask value so as to generate an intermediate value. Result circuitry then generates a result indicative of whether or not the number of adjacent bits is less than or equal to the run length in dependence upon a determination if any bits within the intermediate value have a predetermined value.

Abstract: An apparatus and method are provided for performing vector processing operations. In particular the apparatus has processing circuitry to perform the vector processing operations and an instruction decoder to decode vector instructions to control the processing circuitry to perform the vector processing operations specified by the vector instructions. The instruction decoder is responsive to a vector generating instruction identifying a scalar start value and wrapping control information, to control the processing circuitry to generate a vector comprising a plurality of elements. In particular, the processing circuitry is arranged to generate the vector such that the first element in the plurality is dependent on the scalar start value, and the values of the plurality of elements follow a regularly progressing sequence that is constrained to wrap as required to ensure that each value is within bounds determined from the wrapping control information.

Abstract: An apparatus and method are provided for efficiently performing arithmetic operations that include at least a multiplication operation. The apparatus comprises processing circuitry to perform data processing operations, and instruction decode circuitry responsive to program instructions to generate control signals to control the processing circuitry to perform the data processing operations. In response to an arithmetic operation with shift instruction specifying performance of an arithmetic operation comprising at least a multiplication operation, and having a field which provides a programmable shift indication, the instruction decode circuitry is configured to control the processing circuitry to perform the arithmetic operation during which an intermediate value is produced, and to select a target portion of the intermediate value based on an output window determined from the programmable shift indication.

Abstract: An apparatus comprises: processing circuitry to perform data processing; and an instruction decoder to control the processing circuitry to perform an anchored-data processing operation to generate an anchored-data element. The anchored-data element has an encoding including type information indicative of whether the anchored-data element represents: a portion of bits of a two's complement number, said portion of bits corresponding to a given range of significance representable using the anchored-data element; or a special value other than said portion of bits of a two's complement number.

Abstract: An apparatus has processing circuitry comprising an L×M multiplier array. An instruction decoder associated with the processing circuitry supports a multiply-and-accumulate-product (MAP) instruction for generating at least one result element corresponding to a sum of respective E×F products of E-bit and F-bit portions of J-bit and K-bit operands respectively, where 1<E<J?L and 1<F<K?M. In response to the MAP instruction, the instruction decoder controls the processing circuitry to rearrange F-bit portions of the second K-bit operand to form a transformed K-bit operand, and to control the L×M multiplier array in dependence on the first J-bit operand and the transformed K-bit operand to add the respective E×F products using a subset of the adders used for accumulating partial products for a conventional multiplication.

Abstract: An apparatus and method are provided for performing multiply-and-accumulate-products (MAP) operations. The apparatus has processing circuitry for performing data processing, the processing circuitry including an adder array having a plurality of adders for accumulating partial products produced from input operands. An instruction decoder is provided that is responsive to a MAP instruction specifying a first J-bit operand and a second K-bit operand, to control the processing circuitry to enable performance of a number of MAP operations, where the number is dependent on a parameter. For each performed MAP operation, the processing circuitry is arranged to generate a corresponding result element representing a sum of respective E×F products of E-bit portions within an X-bit segment of the first operand with F-bit portions within a Y-bit segment of the second operand, where E<X?J and F<Y?K.

Abstract: Area-efficient logic circuitry for checkpointing a register file using a mapper in an “in-order” CPU (central processing unit). A pair of flops with a shared master stage latch circuit implement storage elements in a register file and a checkpointed copy of the same register file.

Abstract: Circuitry comprises: a set of bit processing circuitries to apply two or more successive instances of bitwise processing to an ordered bit array; each bit processing circuitry for a given bit position within the ordered bit array comprising: bit shifting circuitry to selectively apply a bit shift of a respective input bit to a next bit processing circuitry in a first direction relative to the ordered bit array, in response to an active state of a bit shift control signal, the bit shifting circuitry not applying the bit shift in response to an inactive state of the bit shift control signal; and bit shift control circuitry to selectively allow or inhibit a bit shifting operation in response to one or more inhibit control signals; in which: the bit shift control circuitry is configured to selectively propagate an output inhibit control signal, indicating that a bit shifting operation should be inhibited, as an inhibit control signal to bit processing circuitry applying a next instance of the bitwise processing a

Abstract: An in-order processor has a mapping storage element to store current register mapping information identifying, for each of two or more architectural register specifiers, which physical register specifies valid data for that architectural register specifier. At least one checkpoint storage element stores checkpoint register mapping corresponding to a checkpoint of previous architectural state. This enables checkpoints to be saved and restored simply by transferring mapping information between the mapping and checkpoint storage elements, rather than transferring the actual state data.

Abstract: A data processing system includes instruction decoder circuitry responsive to a conversion instruction FCVTJS to convert a double precision floating point number into a 32-bit integer number. Right shifting circuitry performs a right shift upon at least part of the input number and left shifting circuitry performs a left shift of at least part of the input number. Selection circuitry serves to select one of the right shifted number and the left shifted number as a selected shifted number which forms at least part of the output number which is generated.

Abstract: Circuitry comprises: a set of bit processing circuitries to apply two or more successive instances of bitwise processing to an ordered bit array; each bit processing circuitry for a given bit position within the ordered bit array comprising: bit shifting circuitry to selectively apply a bit shift of a respective input bit to a next bit processing circuitry in a first direction relative to the ordered bit array, in response to an active state of a bit shift control signal, the bit shifting circuitry not applying the bit shift in response to an inactive state of the bit shift control signal; and bit shift control circuitry to selectively allow or inhibit a bit shifting operation in response to one or more inhibit control signals; in which: the bit shift control circuitry is configured to selectively propagate an output inhibit control signal, indicating that a bit shifting operation should be inhibited, as an inhibit control signal to bit processing circuitry applying a next instance of the bitwise processing a

Abstract: An apparatus and method are provided for performing arithmetic operations to accumulate floating-point numbers. The apparatus comprises execution circuitry to perform arithmetic operations, and decoder circuitry to decode a sequence of instructions. A convert and accumulate instruction is provided, and the decoder circuitry is responsive to decoding the convert and accumulate instruction to generate one or more control signals to control the execution circuitry to convert at least one floating-point operand identified by the convert and accumulate instruction into a corresponding N-bit fixed-point operand having M fraction bits, where M is less than N and M is dependent on a format of the floating-point operand. The execution circuitry accumulates each corresponding N bit fixed-point operand and a P bit fixed-point operand identified by the convert and accumulate instruction in order to generate a P bit fixed-point result value, where P is greater than N and also has M fraction bits.

Abstract: An apparatus has processing circuitry comprising an L×M multiplier array. An instruction decoder associated with the processing circuitry supports a multiply-and-accumulate-product (MAP) instruction for generating at least one result element corresponding to a sum of respective E×F products of E-bit and F-bit portions of J-bit and K-bit operands respectively, where 1<E<J?L and 1<F<K?M. In response to the MAP instruction, the instruction decoder controls the processing circuitry to rearrange F-bit portions of the second K-bit operand to form a transformed K-bit operand, and to control the L×M multiplier array in dependence on the first J-bit operand and the transformed K-bit operand to add the respective E×F products using a subset of the adders used for accumulating partial products for a conventional multiplication.

Abstract: An apparatus and method are provided for performing multiply-and-accumulate-products (MAP) operations. The apparatus has processing circuitry for performing data processing, the processing circuitry including an adder array having a plurality of adders for accumulating partial products produced from input operands. An instruction decoder is provided that is responsive to a MAP instruction specifying a first J-bit operand and a second K-bit operand, to control the processing circuitry to enable performance of a number of MAP operations, where the number is dependent on a parameter. For each performed MAP operation, the processing circuitry is arranged to generate a corresponding result element representing a sum of respective E×F products of E-bit portions within an X-bit segment of the first operand with F-bit portions within a Y-bit segment of the second operand, where E<X?J and F<Y?K.

Abstract: An apparatus and method are provided for processing input operand values. The apparatus has a set of vector data storage elements, each vector data storage element providing a plurality of sections for storing data values. A plurality of lanes are considered to be provided within the set of storage elements, where each lane comprises a corresponding section from each vector data storage element. Processing circuitry is arranged to perform an arithmetic operation on an input operand value comprising a plurality of portions, by performing an independent arithmetic operation on each of the plurality of portions, in order to produce a result value comprising a plurality of result portions. Storage circuitry is arranged to store the result value within a selected lane of the plurality of lanes, such that each result portion is stored in a different vector data storage element within the corresponding section for the selected lane.

Abstract: An apparatus and method are provided for performing arithmetic operations to accumulate floating-point numbers. The apparatus comprises execution circuitry to perform arithmetic operations, and decoder circuitry to decode a sequence of instructions in order to generate control signals to control the arithmetic operations performed by the execution circuitry. A convert and accumulate instruction is provided, and the decoder circuitry is responsive to decoding such a convert and accumulate instruction within the sequence of instructions to generate one or more control signals to control the execution circuitry. In particular, the execution circuitry is responsive to such control signals to convert at least one floating-point operand identified by the convert and accumulate instruction into a corresponding N-bit fixed-point operand having M fraction bits, where M is less than N and M is dependent on a format of the floating-point operand.

Abstract: Processing circuitry is provided to perform an overlap propagating operation on a first data value to generate a second data value, the first and second data values having a redundant representation representing a P-bit numeric value using an M-bit data value comprising a plurality of N-bit portions, where M>P>N. In the redundant representation, each N-bit portion other than a most significant N-bit portion includes a plurality of overlap bits having a same significance as a plurality of least significant bits of a following N-bit portion. Each N-bit portion of the second data value other than a least significant N-bit portion is generated by adding non-overlap bits of a corresponding N-bit portion of the first data value to the overlap bits of a preceding N-bit portion of the first data value. This provides a faster technique for reducing the chance of overflow during addition of the redundantly represented M-bit 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.

Abstract: Data processing apparatus comprises processing circuitry to selectively apply vector processing operations to one or more data items of one or more data vectors each comprising an ordered plurality of data items at respective vector positions in the data vector, according to the state of respective predicate indicators associated with the vector positions; predicate generation circuitry to apply a processing operation to generate an ordered set of predicate indicators, each associated with a respective one of the vector positions, the ordered set of predicate indicators being associated with an ordered set of active indicators each having an active or an inactive state; and a detector to detect a status flag indicative of whether a predicate indicator at a position, in the ordered set of predicate indicators, corresponding to the position of an outermost active indicator having the active state, has a given state; in which the detector comprises: first and second circuitry to combine the ordered set of predic

Abstract: Data processing apparatus comprises: processing circuitry to selectively apply vector processing operations to one or more data items of one or more data vectors each comprising a plurality of data items at respective vector positions in the data vector, according to the state of respective predicate indicators associated with the vector positions; a predicate store; and predicate generation circuitry to apply a processing operation to generate a set of predicate indicators, each associated with a respective one of the vector positions, to generate a count value indicative of the number of predicate indicators in the set having a given state, and to store the generated set of predicate indicators and the count value in the predicate store.