Pipeline processing apparatus with improved efficiency of branch prediction, and method therefor

A pipeline processing apparatus for executing a branch prediction of a conditional branch instruction based on the history of results of branching, the pipeline processing apparatus comprising:

• a branch prediction status memory unit for storing a branch prediction status of a conditional branch instruction, the stored branch prediction status being read according to a current instruction fetch address;
• a branch prediction execution unit for predicting whether a branch condition of a conditional branch instruction is satisfied or non-satisfied based on the branch prediction status stored in the branch prediction status memory unit, and for instructing that a branch destination address is selected as the instruction fetch address when it has been predicted that the branch condition of the conditional branch instruction is satisfied;
• a branch prediction deciding unit for deciding whether a branch prediction executed by the branch prediction execution unit according to a result of a decision on the branch condition is correct or wrong at the time of the execution of the conditional branch instruction, and for instructing that an address of the instruction to be executed next to the conditional branch instruction is selected as the instruction fetch address when it has been decided that the branch prediction is wrong;
• a branch prediction status updating unit for updating the branch prediction status stored in the branch prediction status memory unit based on a result of a decision on the branch condition;
• a selector for selecting a latest branch prediction status updated by the branch prediction status updating unit, and for supplying the latest branch prediction status to the branch prediction execution unit;
• and
• a bypass controller for comparing a conditional branch instruction address at a preceding pipeline stage with an instruction address at a succeeding pipeline stage, and for controlling to supply the updated latest branch prediction status to the succeeding conditional branch instruction that is the same as the preceding conditional branch instruction when both addresses coincide with each other.