Patent
1995-09-11
1998-10-06
Teska, Kevin J.
G06F 900
Patent
active
058190635
ABSTRACT:
A method and data processing system for emulating a program are disclosed. According to the present invention, the data processing system runs under a first operating system and emulates the execution of a program under a second operating system within a second data processing system. The data processing system includes a memory which stores at least a portion of the first operating system and an emulator comprising a plurality of routines which each emulate an instruction utilized by the first operating system. The memory further includes a simulated mass storage data area which stores at least a portion of the program and a simulated main memory data area. The data processing system further includes a processor which executes instructions within the program under the first operating system by emulation. According to the present invention, the emulator accesses instructions of the program directly from the simulated mass storage data area to minimize emulation overhead. According to a second aspect of the present invention, the data processing system further includes a cache memory comprising a number of cache lines. The routines are stored within main memory such that when the routines are mapped into the cache, a first instruction within each of the emulation routines is aligned with a different one of the cache lines. According to a third aspect of the present invention, when executing instructions within a routine of a first emulated instruction, the processor prefetches a second emulated instruction prior to completion of the first emulated instruction.
REFERENCES:
patent: 4638423 (1987-01-01), Ballard
patent: 4755933 (1988-07-01), Teshima et al.
patent: 4839797 (1989-06-01), Katori et al.
patent: 4841476 (1989-06-01), Mitchell et al.
patent: 5226164 (1993-07-01), Nadas et al.
patent: 5280593 (1994-01-01), Bullions, III et al.
patent: 5301302 (1994-04-01), Blackard et al.
patent: 5313614 (1994-05-01), Goettelmann et al.
patent: 5317754 (1994-05-01), Blandy et al.
patent: 5408624 (1995-04-01), Raasch et al.
patent: 5479616 (1995-12-01), Garibay, Jr. et al.
patent: 5560013 (1996-09-01), Scalzi et al.
patent: 5598560 (1997-01-01), Benson
Dahl Stephen A.
Endicott John C.
Heyrman Peter J.
Kirkman R. Karl
Mustain Richard G.
Dillon Andrew J.
International Business Machines - Corporation
Loppnow Matthew Clay
Teska Kevin J.
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