Branch prediction apparatus and method
AssigneeFujitsu Limited
InventorMasaki Ukai
Life of this patent
Estimating the term…
Abstract
A branch prediction apparatus has a configuration such that a predicted branch target address and an offset are obtained by referring to a branch history, an instruction fetch address and the offset are added to obtain a branch instruction address, the branch instruction address is subtracted from the predicted branch target address to obtain a predicted displacement, and this predicted displacement is compared with a displacement cut-out from an instruction by an instruction decoder, to judge whether the predicted branch target address is correct or not.
Claims20
A branch prediction apparatus that predicts a branch target address of a branch instruction, and makes a judgment whether a predicted branch target address agrees with an actual branch target address, the branch prediction apparatus comprising:
- a predicted relative address generation unit that generates a predicted relative address from the predicted branch target address and a reference address;
- and
- a prediction judgment unit that makes the judgment by comparing the generated predicted relative address with an actual relative address of the branch instruction.
A branch prediction method of predicting a target address of a branch instruction, and making a judgment whether a predicted branch target address agrees with an actual branch target address, the branch prediction method comprising steps of:
- generating a predicted relative address from the predicted branch target address and a reference address;
- and
- making the judgment by comparing the generated predicted relative address with the actual relative address of the branch instruction.
Dependencies are inferred from the claim text.