Method and system for processing logic blocks in a data processing system

• US 5,640,557 A
• Filed: 11/18/1994
• Issued: 06/17/1997
• Est. Priority Date: 11/18/1994
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: McKiel, Frank Albert Jr.
• Primary Examiner(s): Black, Thomas G.
• Assistant Examiner(s): Lintz, Paul R.
• Application Number:
  US08/342,072
• Time in Patent Office: 942 Days
• Field of Search: 395/600, 395/650, 395/375, 395/611, 395/726, 364/578, 379/223
• US Class Current: 1/1
• CPC Class Codes: G06F 2111/12 Symbolic schematics
• CPC Class Codes: G06F 30/20 Design optimisation, verification or simulation optimisation, verification or simulation of circuit designs G06F30/30

Abstract

A method and apparatus for evaluating a plurality of logical elements connected to each other by a plurality of connectors, wherein a change of state may occur in at least one of the plurality of logical elements. A state data field is established for each of the plurality of connectors. State data is used within each connection to compare and asserted output of one node with the acknowledged input of another node. Logical elements that require reevaluation are identified from the plurality of elements. By searching for discrepancies within the state data field(s).

Claims

1. A method in a data processing system for evaluating a plurality of logical elements connected to each other by a plurality of connectors, each of said plurality of connectors beinq associated with a source logical element and a destination logical element, wherein a change of state may occur in at least one of said plurality of logical elements, said method comprising:

establishing a state data field associated with each of said plurality of connectors by storing a hiqh byte and a low byte for each of said plurality of connectors;

changing said state data field in response to a change of state in a logical element to reflect said change of state in said logical element by alterinq said high byte associated with a connector in response to a change in state which occurs in a source logical element and altering said low byte associated with a connector when a destination node associated with said connector acknowledges said change of state in said source logical element;

identifying logical elements from said plurality of logical elements that require evaluation by utilizing said state data field;

evaluating said identified logical elements in response to an identification of said identified logical elements.

2. The method of claim 1, wherein said step of identifying comprises identifying logical elements from said plurality of logical elements that require evaluation by comparing a high byte associated with a connector to a low byte associated with said connector.

3. A data processing system for evaluating a plurality logical elements connected to each other by a plurality of connectors each of said plurality of connectors being associated with a source logical element and a destination logical element, wherein a change of state may occur in at least one of said plurality of logical elements, said data processing system comprising:

establishment means for establishing a state data field associated with each of said plurality of connectors by storing a high byte and a low byte for each of said plurality of connectors;

alteration means for changing said state data field in response to a change of state in a logical element to reflect said change of state in said logical element by altering said high byte associated with a connector in response to a change in state which occurs in a source logical element and altering said low byte associated with a connector when a destination node associated with said connector acknowledges said change of state in said source logical element;

identification means for identifying logical elements from said plurality of logical elements that require evaluation by utilizing said state data field;

evaluation means for evaluating said identified logical elements in response to an identification of said identified logical elements.

4. The data processing system of claim 3, wherein identification means for identifying logical elements from said plurality of logical elements that require evaluation by comparing a high byte associated with a connector to a low byte associated with said connector.