Abstract: A processing apparatus comprising a register that stores operand data, a register data reading section that reads operand data stored in the register, a coefficient table set storage section that stores a coefficient table storing Taylor series operation coefficient data, a coefficient data reading section that reads the Taylor series coefficient data from the coefficient table set storage section using the degree information of the Taylor series and the coefficient table identification information and a floating point multiply-adder that executes the Taylor series operation using the coefficient data read by the coefficient data reading section, data read from the register.

Abstract: A cache memory having a sector function, operating in accordance with a set associative system, and performing a cache operation to replace data in a cache block in the cache way corresponding to a replacement cache way determined upon an occurrence of a cache miss comprises: storing sector ID information in association with each of the cache ways in the cache block specified by a memory access request; determining, upon the occurrence of the cache miss, replacement way candidates, in accordance with sector ID information attached to the memory access request and the stored sector ID information; selecting and outputting a replacement way from the replacement way candidates; and updating the stored sector ID information in association with each of the cache ways in the cache block specified by the memory access request, to the sector ID information attached to the memory access request.

Abstract: A priority control register 104 dynamically controls the internal transition state based on the issuability state of a memory request obtained in the memory request issuability signal generation unit 106 and retaining state of the memory request in the REQ_BUF 102 obtained by each of determination circuits 105 #2 through #5. Thus, the jump control of the priorities corresponding to the access regulation of the DRAM module 109 can be realized.

Abstract: A processing unit computes a trigonometric function, for decrease the number of instructions and improve throughput. In a floating point multiply-add circuit, an OR circuit, a selector and an EOR circuit are disposed, and an expansion point and expansion function of the Taylor series expansion of the trigonometric function are computed using a first trigonometric function operation auxiliary instruction for defining the operation of rd=(rs1*rs1)|(rs2 [0]<<63) and a second trigonometric function operation auxiliary instruction for defining the operation of rd=((rs2 [0])? 1.0: rs1)^(rs2 [1]<<63), or a third trigonometric function operation auxiliary instruction for defining the operation of rd=(rs1*rs1)|((˜rs2 [0]<<63) and a fourth trigonometric function operation auxiliary instruction for defining the operation of rd=((rs2 [0])? rs1: 1.0)^((rs2 [1]^rs2 [0])<<63)).

Abstract: A processing unit has an extended register to which instruction extension information indicating an extension of an instruction can be set. An operation unit that, when instruction extension information is set to the extended register, executes a subsequent instruction following a first instruction for writing the instruction extension information into the extended register, extends the subsequent instruction based on the instruction extension information.

Abstract: A priority control register 104 dynamically controls the internal transition state based on the issuability state of a memory request obtained in the memory request issuability signal generation unit 106 and retaining state of the memory request in the REQ_BUF 102 obtained by each of determination circuits 105 #2 through #5. Thus, the jump control of the priorities corresponding to the access regulation of the DRAM module 109 can be realized.

Abstract: A processor equipped with a pre-fetch function comprises: first layer cache memory having a first line size; second layer cache memory that is on the under layer of the first layer cache memory and that has a second line size different from the first line size; and a pre-fetch control unit for issuing a pre-fetch request from the first layer cache memory to the second layer cache memory so as to pre-fetch a block equivalent to the first line size for each second line size.

Abstract: A cache memory for operating in accordance with a multi-way set associative system, the cache memory includes an identification information storage for storing an identification information for identifying a requesting element of a memory access request corresponding to a cache block specified by a received memory access request, a replacement cache block candidate determinator for determining, upon an occurrence of a cache miss corresponding to the memory access request, a candidate of the cache block for replacing, on the basis of the identification information attached to the memory access request and the identification information stored in the identification information storage corresponding to the cache block specified by the memory access request, and a replacement cache block selector for selecting a replacement cache block from the candidate.

Abstract: A processing unit computes a trigonometric function, for decrease the number of instructions and improve throughput. In a floating point multiply-add circuit, an OR circuit, a selector and an EOR circuit are disposed, and an expansion point and expansion function of the Taylor series expansion of the trigonometric function are computed using a first trigonometric function operation auxiliary instruction for defining the operation of rd=(rs1*rs1)|(rs2 [0]<<63) and a second trigonometric function operation auxiliary instruction for defining the operation of rd=((rs2 [0])? 1.0: rs1)?(rs2 [1]<<63), or a third trigonometric function operation auxiliary instruction for defining the operation of rd=(rs1*rs1)|((˜rs2 [0]<<63) and a fourth trigonometric function operation auxiliary instruction for defining the operation of rd=((rs2 [0])? rs1: 1.0)?((rs2 [1]?rs2 [0])<<63)).

Abstract: A branch prediction apparatus reads out a branch history table 15 by an index calculated by the output of a branch history register 14 containing a plurality of the latest branch result of a branch instruction. The branch prediction apparatus comprises frequency detection units 18-20 for detecting the appearance frequency of a branch instruction with a different address and data width modification units 16 and 21 for modifying the number of valid bits of the branch history register, based on the detected appearance frequency. Even a program in which a branch result strongly depends on the latest branch history or even a program having a plenty of branch instructions can maintain high prediction accuracy with a small capacity of the branch history table.

Abstract: A processing unit has an extended register to which instruction extension information indicating an extension of an instruction can be set. An operation unit that, when instruction extension information is set to the extended register, executes a subsequent instruction following a first instruction for writing the instruction extension information into the extended register, extends the subsequent instruction based on the instruction extension information.

Abstract: A cache memory having a sector function, operating in accordance with a set associative system, and performing a cache operation to replace data in a cache block in the cache way corresponding to a replacement cache way determined upon an occurrence of a cache miss comprises: storing sector ID information in association with each of the cache ways in the cache block specified by a memory access request; determining, upon the occurrence of the cache miss, replacement way candidates, in accordance with sector ID information attached to the memory access request and the stored sector ID information; selecting and outputting a replacement way from the replacement way candidates; and updating the stored sector ID information in association with each of the cache ways in the cache block specified by the memory access request, to the sector ID information attached to the memory access request.

Abstract: A processor equipped with a pre-fetch function comprises: first layer cache memory having a first line size; second layer cache memory that is on the under layer of the first layer cache memory and that has a second line size different from the first line size; and a pre-fetch control unit for issuing a pre-fetch request from the first layer cache memory to the second layer cache memory so as to pre-fetch a block equivalent to the first line size for each second line size.

Abstract: A processing apparatus comprising a register that stores operand data, a register data reading section that reads operand data stored in the register, a coefficient table set storage section that stores a coefficient table storing Taylor series operation coefficient data, a coefficient data reading section that reads the Taylor series coefficient data from the coefficient table set storage section using the degree information of the Taylor series and the coefficient table identification information and a floating point multiply-adder that executes the Taylor series operation using the coefficient data read by the coefficient data reading section, data read from the register.

Abstract: A branch prediction apparatus reads out a branch history table 15 by an index calculated by the output of a branch history register 14 containing a plurality of the latest branch result of a branch instruction. The branch prediction apparatus comprises frequency detection units 18-20 for detecting the appearance frequency of a branch instruction with a different address and data width modification units 16 and 21 for modifying the number of valid bits of the branch history register, based on the detected appearance frequency. Even a program in which a branch result strongly depends on the latest branch history or even a program having a plenty of branch instructions can maintain high prediction accuracy with a small capacity of the branch history table.

Abstract: An instruction issuing device comprises a plurality of issue controlling circuits which run in parallel, and perform a control for preferentially issuing an instruction to a particular arithmetic unit. An optimum issue controlling circuit is selected according to the empty quantity of instruction slots for each arithmetic unit or a result of learning of the number of previously issued instructions, and an issue destination is determined based on the direction of the selected circuit.

Abstract: An instruction issuing device comprises a plurality of issue controlling circuits which run in parallel, and perform a control for preferentially issuing an instruction to a particular arithmetic unit. An optimum issue controlling circuit is selected according to the empty quantity of instruction slots for each arithmetic unit or a result of learning of the number of previously issued instructions, and an issue destination is determined based on the direction of the selected circuit.