22.9.1. Load multiple-load-CDP resource hazard
example
In Example 22.10,
the FLDM is executing two transfers to the VFP11 coprocessor.
The FLDS is stalled behind the FLDM until
the FLDM enters the final Execute cycle. The FADDS is
stalled for one cycle until the FLDS begins execution.
Example 22.10. FLDM-FLDS-FADDS resource hazard
FLDM [R2], {S8-S10}
FLDS [R4], S16
FADDS S2, S3, S4
Table 22.12 shows
the pipeline stages for Example 22.10.
Table 22.12. FLDM-FLDS-FADDS resource hazard
| | Instruction cycle number |
|---|
| Instruction | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 |
|---|
FLDM | D | I | E | M1 | M2 | W | W | - | - | - | - | - | - |
FLDS | - | D | D | I | E | M1 | M2 | W | - | - | - | - | - |
FADDS | - | - | - | D | I | E1 | E2 | E3 | E4 | E5 | E6 | E7 | W |
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