Microsoft Corporation
Tracking and communication of direct/indirect source dependencies of producer instructions executed in a processor to source dependent consumer instructions to facilitate processor optimizations

Abstract:

Tracking and communication of direct/indirect source dependencies of producer instructions executed in a processor to source dependent consumer instructions to facilitate processor optimizations. The processor includes instruction processing circuit configured to process and execute fetched instructions in an instruction stream according to a dataflow execution. The instruction processing circuit includes mechanisms to communicate dependencies to dependent, consumer instructions in an instruction pipeline to facilitate processor optimizations, such as replay of consumer instructions. The instruction processing circuit is configured to track producer instructions and consumer instruction dependencies on its producer instructions in the instruction pipeline in a data structure circuit before the instructions are scheduled for execution. These recorded source dependencies in the source dependency indicators can then be communicated to later stages in the instruction pipeline, such as scheduling, to facilitate for example, replay of dependent consumer instructions, if for example, its producer instruction incurs a hazard.