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Branch instruction without delay slot, Operation of branch instruction without delay slot – FUJITSU MB91460 SERIES FR60 User Manual

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Chapter 7 Branch Instruction

5.Branch Instruction without Delay Slot

5. Branch Instruction without Delay Slot

• Branch instruction without delay slot:

6. Operation of Branch Instruction without Delay Slot

Operation without delay slot executes instructions in the order of instructions and never executes
the instruction located in the next address where a branch instruction exists before branch.

• Example

The number of execution cycles of branch instruction without delay slot is 2 cycles for branch and 1
cycle for no branch.

Unlike the branch instruction with delay slot where NOP is described because appropriate
instruction cannot be entered, it can increase efficiency of instruction code.

Select the operation with delay slot when valid instruction can be set in delay slot. Otherwise select
the operation without delay slot. This selection enables FR60 to satisfy both of execution rate and
code efficiency.

JMP @Ri

CALL label12

CALL @Ri

RET

BRA label9

BNO label9

BEQ label9

BNE label9

BC label9

BNC label9

BN label9

BP label9

BV label9

BNV label9

BLT label9

BGE label9

BLE label9

BGT label9

BLS label9

BHI label9

;

Sequence of instruction

ADD

R1

R2

;

BRA:D

LABEL

; Branch instruction (without delay slot)

MOV

R2

R3

; Not to be executed.

...

LABEL ST

R3

@R4 ; Branched instruction