Hitachi, Ltd.

Hitachi Vlsi Engineering Corp.

Fujio Yamamoto

Hiroshi Nishida

Takeshi Wada

Susumu Hatano

Yasushi Takahashi

Jun Naruse

Masayasu Kawamura

Shin'ichi Ikenaga

Makoto Satoh

Jun Kitano

Kenji Nishimoto

Kiyomi Umehara

Mikio Higashi

Michihiro Mishima

A computation partitioning method is arranged to automatically convert a sequential source program for a single processor into a partitioned computation for a distributed memory machines containing plural processors. The method is executed to analyze a syntax of a source program described in a high-level language containing at least one loop having plural assignment statements, each assignment having an array, distribute the array element in the source program and at least one loop and allocate the partitioned parts of the array element to the processors. For each processor, then, the method is further executed to derive a loop iteration set corresponding to an array element distributed to the processor for plural assignment statements in at least one loop and generate a new array having the sum set of the derived loop iteration set as its array elements. By using the new generated array index as the loop iteration set of the assignment statements in at least one loop, the partitioned computation to be executed by each processor is generated.

Method for partitioning computation

Herein disclosed is a semiconductor integrated circuit for testing test data of two kinds of non-inverted and inverted statuses of all bits by itself with a prospective data of one kind to compress and output the test results. The semiconductor integrated circuit includes a decide circuit 25 for deciding a first status, in which the prospective data latched by a pattern register and the read data of a memory cell array are coincident, a second status, in which the read data is coincident with the logically inverted data of the prospective data, and a third statuses other than the first and second statuses through an exclusive OR gate to generate signals of 2 bits capable of discriminating the individual statuses. These statuses are informed to the outside of the semiconductor integrated circuit in accordance with high- and low-levels and a high-impedance.

Semiconductor memory device

For candidates of a plurality of data dividing patterns which are expressed by using a data dividing pattern library, in a case where data and program are allocated to each processor by a method which has been predetermined in correspondence to each data dividing pattern and are executed, an evaluating program to measure an amount about the processing time is produced. By executing the evaluating program by a sequential computer, a plurality of data division candidates are compared and evaluated and the optimum data division is selected. Distributed memory parallel programs are produced in accordance with the optimum data division.

Evaluating method of data division patterns and a program execution time

A spindle assembly for magnetic disks of both-end support type has a hub for fixing the disks, a shaft to which the hub is fixed, a pair of bearings which are spaced in vertical or horizontal direction, a pre-loading spring for pre-loading one of the bearings, and a housing composed of housing parts which accommodates the hub, shaft, bearings and the pre-loading spring. The spindle assembly further has an axial reference surface formed on the hub at a right angle with respect to the shaft, and another axial reference surface formed on one of the housing parts at a right angle with respect to the vertical portion of the bearing associated with the one of the housing parts. When the shaft is mounted in the one of the housing parts with the hub and the pre-loading spring fitted therearound, the hub is axially urged by the spring such that the axial reference surface thereon is brought into abutment with the axial reference surface on the one of the housing parts. As a result, the axis of the spindle assembly is determined by the abutment between the reference surfaces and by the bearing in the one of the housing parts. The bearing in the other of the housing parts is axially aligned with the thus determined axis of the spindle assembly.

Spindle assembly for magnetic disks

Growing community of inventors

Higashiyamato, Japan

Fujio Yamamoto