Functional Unit Constraints
4-47PipelineSPRU733
Table 4−31 shows the instruction constraints for MPYSP2DP instructions
executing on the .M unit.
Table 4−31. MPYSP2DP .M-Unit Instruction Constraints
Instruction Execution
Cycle 1 2 3 4 5
MPYSP2DP R R W W
Instruction Type
Subsequent Same-Unit Instruction Executable
16 × 16 multiply Xw Xw
MPYDP
Xu
MPYI
Xu
MPYID
Xu
MPYSP
Xw
MPYSPDP
Xu
MPYSP2DP
Xw
Instruction Type
Same Side, Different Unit, Both Using Cross Path Executable
Single-cycle Xr
Load Xr
Store
Xr
DP compare
Xr
2-cycle DP
Xr
Branch
Xr
4-cycle
Xr
INTDP
Xr
ADDDP/SUBDP
Xr
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; Xr = Next instruction cannot enter E1 during cycle−read/
decode constraint; Xw = Next instruction cannot enter E1 during cycle−write constraint; Xu = Next instruction cannot
enter E1 during cycle−other resource conflict