Fujitsu Corporation

Noriko Takagi

Yuki Kamikubo

Yasunobu Akizuki

Takahito Hirano

Kenichi Kitamura

Hideki Okawara

Mikio Hondo

An arithmetic processing apparatus includes an arithmetic circuit configured to perform an arithmetic operation on data having a first data width and perform an instruction in parallel on each element of data having a second data width, and a cache memory configured to store data, wherein the cache memory includes a tag circuit storing tags for respective ways, a data circuit storing data for the respective ways, a determination circuit that determines a type of an instruction with respect to whether data accessed by the instruction has the first data width or the second data width, and a control circuit that performs either a first pipeline operation where the tag circuit and the data circuit are accessed in parallel or a second pipeline operation where the data circuit is accessed in accordance with a tag result after accessing the tag circuit, based on a result determined by the determination circuit.

Arithmetic processing apparatus and memory apparatus

An arithmetic processing device includes a memory access request issuance unit and a cache including a cache memory for tags and data and a move-in buffer control unit for issuing a move-in request for data on the memory access request when a cache miss occurs. The move-in buffer control unit, when the cache miss occurs, determines to acquire a move-in buffer and issue the move-in request when the memory access request has the same index as an index of any move-in request registered in the move-in buffer and the number of move-in requests of the same index registered in the move-in buffer is less than the number of ways, and determines not to acquire the move-in buffer and does not issue the move-in request when the memory access request has the same index and the number of the move-in requests of the same index reaches the number of the ways.

Arithmetic processing device having a move-in buffer control unit that issues a move-in request in shorter time upon a memory access request, information apparatus including the same and method for controlling the arithmetic processing device

A processor includes a cache memory, an issuing unit that issues, with respect to all element data as a processing object of a load instruction, a cache request to the cache memory for each of a plurality of groups which are divided to include element data, a comparing unit that compares addresses of the element data as the processing object of the load instruction, and determines whether element data in a same group are simultaneously accessible, and a control unit that accesses the cache memory according to the cache request registered in a load queue registering one or more cache requests issued from the issuing unit. The control unit processes by one access whole element data determined to be simultaneously accessible by the comparing unit.

Processor and control method of processor

An arithmetic processing unit includes a cache including a cache memory for storing states of data and data in a block at an index of the memory access request, a move-in buffer control unit that issues a move-in request when cache miss, and move-in buffers for registering the move-in request. The move-in buffer control unit, in response to cache miss, (a) secures a vacant move-in buffer when the vacant move-in buffer exists, (b) issues a move-in request when a move-in request having a same index as the memory access request is not registered in the move-in buffers, (c) issues the move-in request when the move-in request having the same index is registered in the move-in buffers and all ways are not used by the move-in request having the same index in the move-in buffers, and (d) releases the secured move-in buffer when all the ways are used.

Arithmetic processing unit and method for controlling arithmetic processing unit

An arithmetic processing apparatus includes a cache memory to store data in cache lines, an error detecting unit to detect an error occurring in one of the cache lines, a way comparing unit to compare way identification information of a cache line to be accessed with error-way identification information, a word comparing unit to compare a word address of the cache line to be accessed with an error word address, a column comparing unit to compare a column address of the cache line to be accessed with an error column address, and a control unit to disable all cache lines sharing a failed word line in response to results of comparisons made by the way comparing unit, the word comparing unit, and the column comparing unit when the error detecting unit detects a second error occurring in any one of the cache lines after the occurrence of the first error.

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Kawasaki, Japan

Noriko Takagi