INSTRUCTION CONTROL DEVICE HAVING BRANCHING PREDICTION MECHANISM AND CONTROL METHOD THEREOF

摘要

An instruction control device and control method for suppressing or invalidating an erroneous instruction fetch request or operand request until a re-instruction fetch request is output to a memory when a branching prediction is made incorrectly. In order to achieve this object, an instruction control device fetches an instruction stored in a storage section and executes the instruction in the out-of-order method. The instruction control device includes a branching instruction prediction section for predicting an instruction branching and a branching prediction control section. When the branching prediction control section judges that the branching prediction made by the branching instruction prediction section has been incorrect, the instruction control device suppresses an instruction fetch request which has been output to the storage section and invalidates the instruction already output from the storage section during a period after the branching prediction control section has judged that the branching prediction made by the branching instruction prediction section has been incorrect until a correct instruction is re-fetched from the storage section.