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- FP arithmetic generally consists of several stages.
E.g. FP Addition (H&P pp.A-23)
- Unpack FP operands, deal with signs
- Shift so mantissae are aligned according to exponents
- Add
- Renormalise, accommodating carries
- Round
- Compute sign of result
- Some are functionally distinct from one another and are
therefore efficient to pipeline
- Some units are not easy to pipeline, leading to structural hazards
- Some stages are used in more than one instruction, leading to
potential structural hazards
Paul H J Kelly
Mon Dec 1 20:07:28 GMT 1997