A method and apparatus for predicting load addresses and identifying new threads
of instructions for execution in a multithreaded processor. A load prediction unit
scans an instruction window for load instructions. A load prediction table is searched
for an entry corresponding to a detected load instruction. If an entry is found
in the table, a load address prediction is made for the load instruction and conveyed
to the data cache. If the load address misses in the cache, the data is prefetched.
Subsequently, if it is determined that the load prediction was incorrect, a miss
counter in the corresponding entry in the load prediction table is incremented.
If on a subsequent detection of the load instruction, the miss counter has reached
a threshold, the load instruction is predicted to miss. In response to the predicted
miss, a new thread of instructions is identified for execution.
