Hubexec instruction fetching and REP
evanh
Posts: 15,187
in Propeller 2
Take the following example that I've tacked to the end of test program:
I'm thinking hubexec and cogexec will take exactly the same number of sysclock cycles per loop because instruction fetching triggers a fifo refill while the WAITX is still executing.
Any long executing instruction at the end of the loop will benefit from this. Possibly even a RDLONG although there may be congestion on that one. Admittedly, most are going to be waiting type instructions but a cordic command can take advantage of it.
rep @.rend,#0 drvnot #33 drvnot #56 waitx ##clock_freq .rend
I'm thinking hubexec and cogexec will take exactly the same number of sysclock cycles per loop because instruction fetching triggers a fifo refill while the WAITX is still executing.
Any long executing instruction at the end of the loop will benefit from this. Possibly even a RDLONG although there may be congestion on that one. Admittedly, most are going to be waiting type instructions but a cordic command can take advantage of it.
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