Operand Fetch

• Check the ROBmap entry first

  • If valid bit is False, then this register is not renamed and we need to fetch value from the register file
    • Operand is READY!

• If ROBmap valid bit is TRUE, then operand has been renamed! Look at ROB entry status

  • If ROB status is FINISHED_VALID or FINISHED_INVALID, then ROB destination field has operand value and operand is ready
  • If ROB status is ISSUED_VALID or ISSUED_INVALID, then operand value is not ready (instruction still in execution).

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