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- units
- branch
- integer
- floating point
- on 601
- issue at most one per unit per cycle
- eight entry instruction queue
- can fill queue from cache in one clock cycle
- loads from requested address to end of cache block
- pipeline
- prefetch
- includes ins. cache access cycles
- decode
- execute
- writeback
- fpu
- IQ[3210] → fpu buffer/decode [≥1 cycle] → execute 1 → execute 2 → writeback
- iu
- IQ0/decode → buffer [if exec busy] → execute [hold for dependency] →
- circulate in load/store
- writeback
- bpu
- IQ[3210] → decode/execute → writeback
- notes
- address calculation must complete before stored value enters write buffer
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