Browse Prior Art Database

Link Editor for Virtual Control Section Storage

IP.com Disclosure Number: IPCOM000083623D
Original Publication Date: 1975-Jun-01
Included in the Prior Art Database: 2005-Mar-01
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Smith, HF: AUTHOR

Abstract

Control sections (CS) are variable-length segments of data processing program information. A program stream may include valid op-codes and real addresses, and may include invalid op-codes and invalid addresses, which cause a program check interruption. The program check may then be used to obtain address translation and storage segment swapping to effect a virtual memory.

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Link Editor for Virtual Control Section Storage

Control sections (CS) are variable-length segments of data processing program information. A program stream may include valid op-codes and real addresses, and may include invalid op-codes and invalid addresses, which cause a program check interruption. The program check may then be used to obtain address translation and storage segment swapping to effect a virtual memory.

Specifically, a link editor may be provided to create a program stream which will operate as above. The link editor alters object modules to provide a real-load module, which is always resident and virtual load modules of virtual control sections. It further alters the inter-CS and intra-CS address references, respectively, to an invalid address and to an address relative to the beginning of the CS.

The link editor further scans the text of the virtual object modules, to replace all op-codes which store away real addresses for subsequent reference with invalid op-codes. During machine execution, all invalid addresses and op-codes cause program checks which are interpreted to cause the desired operation, but with virtual rather than real addresses.

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