Patent ID: 8291196
Filing Date: 2012-10-16
Classification: G06F

Abstract:
1. An apparatus comprising: an instruction buffer to store an instruction stream having a single entry point and a single exit point, the instruction buffer including a plurality of instruction buffer entry locations; and a dead instruction identifier to identify dead instructions in the instruction stream based on a forward pass through the instruction stream, the dead instruction identifier including a destination table to store, for each destination at which data is to be stored in the instruction stream, one of a plurality of index values, each of the plurality of index values corresponding to exactly one of the plurality of instruction buffer entry locations, to identify which instruction in the instruction stream is to produce the data to be stored at the destination, the dead instruction identifier also including a producer table to track, for each consumer instruction in the instruction stream, all instructions that are to produce data to be used by the consumer instruction, by storing indicators to indicate whether each other instruction in the producer table produces data for the consumer instruction, the storing indicators including storing the result of a logical OR operation using indicators stored for at least two of the other instructions in the producer table that produce data for the consumer instruction.