what the meaning of cycle in or1ksim

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what the meaning of cycle in or1ksim

by yueng :: Rate this Message:

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for example
  00002a50: d7e21fb4  l.sw -76(r2),r3 (executed) [cycle 4417245, #121308]
  00002a54: 18800004  l.movhi r4,0x4 (next insn)
            18800004  l.movhi r4,0x4 (executed) [cycle 4417265, #121309]

  why only a mov instruction use 20 cycles? i think this will only cost one cycle.

  thank you

Re: what the meaning of cycle in or1ksim

by Dimitri?s Orfanos :: Rate this Message:

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or1ksim does not count CPI (clocks per instruction) but only simulation
cycles and memory cycles. If you see the sim.cfg in the memory section
has the delay of memory when doing writing or reading. These values are
added with the simulation cycles so far to produce the cycles that you see.

yueng wrote:

> for example
>   00002a50: d7e21fb4  l.sw -76(r2),r3 (executed) [cycle 4417245, #121308]
>   00002a54: 18800004  l.movhi r4,0x4 (next insn)
>             18800004  l.movhi r4,0x4 (executed) [cycle 4417265, #121309]
>
>   why only a mov instruction use 20 cycles? i think this will only cost one
> cycle.
>
>   thank you
>  
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