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Special Instruction to Initiate and Supplement Program Trace Functions

IP.com Disclosure Number: IPCOM000091147D
Original Publication Date: 1969-Nov-01
Included in the Prior Art Database: 2005-Mar-05
Document File: 2 page(s) / 36K

Publishing Venue

IBM

Related People

Ruzicka, H: AUTHOR

Abstract

These special computer instructions are useful in program trace activities. When appropriately inserted at strategic places in a string of ordinary program instructions, the special instructions efficiently flag and supplement program tracing, debugging, or other monitoring functions, without degrading normal productivity of the computer.

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Special Instruction to Initiate and Supplement Program Trace Functions

These special computer instructions are useful in program trace activities. When appropriately inserted at strategic places in a string of ordinary program instructions, the special instructions efficiently flag and supplement program tracing, debugging, or other monitoring functions, without degrading normal productivity of the computer.

Special instructions Hook and Handle are treated as NotOps during normal operation of the computer. Thus, when Normal-Trace Trigger is in Normal state, execution of either special instruction terminates instantly following logical recognition, i.e., decoding, of the instruction operation code OP Code = Bits 0...7.

However, in Trace Mode, Trigger in Trace state, the special instructions are employed to initiate, flag, and supplement tracing operations. The tracing operations can be performed either by the computer or by monitor equipment physically separate from the computer. Thus, when a special instruction is encountered in Trace Mode, the supplemental information, ID Code = Bits 8...15 of the instruction, is presented for examination in the tracing operation. This information is useful, for example, to distinguish between multiple special instructions in a program string e.g., multiple subprograms or loops.

Handle provides additional functions associated with its code fields B1, D1, B2, D2. These designate relative addresses of upper and lower limit positio...