Integer pipeline stages of pentium processor
Answers
Pentium processor uses a five stage pipeline. The stages are as follows:
i. Prefetch stage - The instructions are of variable length and stored in a prefetch buffer. A 256 bit path exists from the instruction cache to the prefetch buffer.
ii. Decode 1 stage - The processor decodes the instruction. It finds the opcode and addressing information. It checks which information can be paired for simultaneous execution. It participates in branch address prediction.
iii. Decode 2 stage - In this stage it finds the addresses for memory reference.
iv. Execute stage - Data cache fetch or ALU or FPU operation is carried out. Two operations can be carried out at this stage.
v. Write back stage - In this stage the registers and flags are updated on the basis of the results of execution.