Delay Slots
3-15
Instruction Set
SPRU733
Table 3
−
8. Delay Slot and Functional Unit Latency
Instruction Type
Delay
Slots
Functional
Unit Latency
Read Cycles
†
Write
Cycles
†
Single cycle
0
1
i
i
2-cycle DP
1
1
i
i, i + 1
DP compare
1
2
i, i + 1
1 + 1
4-cycle
3
1
i
i + 3
INTDP
4
1
i
i + 3, i + 4
Load
4
1
i
i, i + 4
‡
MPYSP2DP
4
2
i
i + 3, i + 4
ADDDP/SUBDP
6
2
i, i + 1
i + 5, i + 6
MPYSPDP
6
3
i, i + 1
i + 5, i + 6
MPYI
8
4
i, i + 1, 1 + 2, i + 3
i + 8
MPYID
9
4
i, i + 1, 1 + 2, i + 3
i + 8, i + 9
MPYDP
9
4
i, i + 1, 1 + 2, i + 3
i + 8, i + 9
†
Cycle i is in the E1 pipeline phase.
‡
A write on cycle i + 4 uses a separate write port from other .D unit instructions.