Patent ID: 7941638

Claim:
A method for performing a fast-scanning operation to generate fetch bundles in an instruction fetch unit (IFU) of a processor, comprising: obtaining a cache line containing instructions at the IFU; performing a complete-scanning operation on the cache line in a complete-scanning circuit to identify control transfer instructions (CTIs) by scanning a first set of instructions in the cache line; at the same time that the complete-scanning operation is performed, separately performing the fast-scanning operation in a fast-scanning circuit to identify CTIs in a group of initial instructions in the cache line by scanning a second set of instructions in the cache line, wherein the second set of instructions is a subset of the first set of instructions that consists of a smaller number of instructions than the first set of instructions; obtaining results from the fast-scanning operation before results of the complete-scanning operation are available; using the results from the fast-scanning operation to form an initial fetch bundle containing initial instructions; and sending the initial fetch bundle to an instruction-issue unit.