Resources Contact Us Home
Fetching all or portion of instructions in memory line up to branch instruction based on branch prediction and size indicator stored in branch target buffer indexed by fetch address

Image Number 7 for United States Patent #8171260.

The invention provides a method and apparatus for branch prediction in a processor. A fetch-block branch target buffer is used in an early stage of pipeline processing before the instruction is decoded, which stores information about a control transfer instruction for a "block" of instruction memory. The block of instruction memory is represented by a block entry in the fetch-block branch target buffer. The block entry represents one recorded control-transfer instruction (such as a branch instruction) and a set of sequentially preceding instructions, up to a fixed maximum length N. Indexing into the fetch-block branch target buffer yields an answer whether the block entry represents memory that contains a previously executed a control-transfer instruction, a length value representing the amount of memory that contains the instructions represented by the block, and an indicator for the type of control-transfer instruction that terminates the block, its target and outcome. Both the decode and execution pipelines include correction capabilities for modifying the block branch target buffer dependent on the results of the instruction decode and execution and can include a mechanism to correct malformed instructions.

  Recently Added Patents
Process for producing .beta.-sialon fluorescent material
Advertising apparatus
Battery-operated massager and soap dispensing wand
Performance metrics processing for anticipating unavailability
Fuel cell stack including ejector and blower for anode recirculation and method for controlling the same
Regulating a supply voltage provided to a load circuit
Load balancing for parallel tasks
  Randomly Featured Patents
No-slack restricted-drum stabilizer for commercial multitrailer combinations
Bicycle suspension-setting adjustor assembly
Adaptive accuracy for enteral feeding pump
Telephony switching apparatus
Beverage bottle
Endotracheal tubes with intubation direction control means
Film bonded fuel cell interface configuration
N-acetylhexosamine oxidase and process for producing the same
Drafting process for preparing a modified polyester fiber