TRACKING DEALLOCATED LOAD INSTRUCTIONS USING A DEPENDENCE MATRIX

摘要

A mechanism is provided for tracking deallocated load instructions. A processor detects whether a load instruction in a set of instructions in an issue queue has missed. Responsive to a miss of the load instruction, an instruction scheduler allocates the load instruction to a load miss queue and deallocates the load instruction from the issue queue. The instruction scheduler determines whether there is a dependence entry for the load instruction in an issue queue portion of a dependence matrix. Responsive to the existence of the dependence entry for the load instruction in the issue queue portion of the dependence matrix, the instruction scheduler reads data from the dependence entry of the issue queue portion of the dependence matrix that specifies a set of dependent instructions that are dependent on the load instruction and writes the data into a new entry in a load miss queue portion of the dependence matrix.