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Re: impact of -minsert-sched-nops


Darit,
   The question I have is how portable is the code generated if I do
the following...

1) On a G5 (Power4) based machine, compile code with 
-minsert-sched-nops=scheme (which I assume will result in 
the default with scheme="regroup_exact" being used). 
2) Move the compiled binaries over to a G4 and try to
run them. Will the use of this scheme in the binary
cause problems on a G4?

I guess I am still a bit confused. If the scheme="regroup_exact"
doesn't cause problems on a G4 but is useful on a G5, it would
seem appropriate to allow users to effectively 'cross-compile'
for the G5 on a G4. That is you ought to be able to do a 
compile with...

-minsert-sched-nops="regroup_exact"

...on a G4 and move that code over to a G5 and have the
scheme "regroup_exact" still function. Again the point is
to be able to access this option for the G5 without resorting
to the -mcpu=670 flag that would make the code use G5-specific
instructions and not run on a G4.
                Jack


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