Fujitsu Corporation

Atsushi Fusejima

Takashi Suzuki

Toshio Yoshida

Yasunobu Akizuki

Norihito Gomyo

A prefetch request circuit is provided in a processor device. The processor device has hierarchized storage areas and can prefetch data of address to be used between appropriate storage areas among the storage areas, when executing respective instruction flows obtained by multi-flow expansion for one instruction at a time of decoding of the instruction. The prefetch request circuit includes a latch unit to hold, when a state in which the respective instruction flows to access the storage area are executed with a maximum specifiable data transfer volume is specified, the state during a time period of the multi-flow expansion; and a prefetch request signal output unit to output a prefetch request signal to request the prefetch every time when the instruction flow is executed, based on an output signal of the latch unit and a signal indicating an execution timing of the respective instruction flows.

Prefetch request circuit

A priority circuit is connected to a reservation station and a plurality of arithmetic units that processes different operations and dispatches, when it is determined that an executable flag indicating that an instruction can be executed by only a specific arithmetic unit is on, an instruction to an arithmetic unit that is different from the specific arithmetic unit and of which a queue is vacant in accordance with the input performed by an instruction decoder and the reservation station.

Dispatching instruction from reservation station to vacant instruction queue of alternate arithmetic unit

A processing unit includes a plurality of thread execution units each provided with a performance analysis circuit for measuring various types of events resulting from execution of instructions and a commit stack entry unit for controlling the completion of executed instructions and each executing a thread having a plurality of instructions, a commit scope register for storing instructions of completion candidates stored in each commit stack entry unit by execution by each thread execution unit and performing processing for completion of instructions included in the thread, and a thread selecting means for sending commit events of the instructions to a performance analysis circuit provided in each thread execution unit corresponding to the instructions when performing commit processing for instructions stored in the commit scope register.

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Kawasaki, Japan

Atsushi Fusejima