Functional Unit Constraints
Pipeline
4-34
SPRU733
4.3.1 .S-Unit Constraints
Table 4
−
18 shows the instruction constraints for single-cycle instructions
executing on the .S unit.
Table 4
−
18. Single-Cycle .S-Unit Instruction Constraints
Instruction Execution
Cycle
1
2
Single-cycle
RW
Instruction Type
Subsequent Same-Unit Instruction Executable
Single-cycle
DP compare
2-cycle DP
ADDDP/SUBDP
ADDSP/SUBSP
Branch
Instruction Type
Same Side, Different Unit, Both Using Cross Path Executable
Single-cycle
Load
Store
INTDP
ADDDP/SUBDP
16
×
16 multiply
4-cycle
MPYI
MPYID
MPYDP
Legend:
= E1 phase of the single-cycle instruction; R = Sources read for the instruction; W = Destinations written for the
instruction;
= Next instruction can enter E1 during cycle