Scheduling and inserting NOPs

[Ian Lance Taylor]

Boris Boesler <baembel@gmx.de> writes:

> Hi!
> 
> Am 13.11.2007 um 19:14 schrieb Ian Lance Taylor:
> 
> > Boris Boesler <baembel@gmx.de> writes:
> >
> >>   1) As far as I can see some levels of optimization do not schedule
> >> the code. To generate correct code I have to insert NOP-operations to
> >> fill the delays (the architecture has no interlocks),
> 
>   ...
> 
> > gcc is weak on VLIW support.  The scheduler does not insert NOPs for
> > you.
> 
>   VLIWs? As I mentioned above the processor does not wait till the
> operands are evaluated; this must be done by the programmer/compiler
> by inserting NOPs or other instructions.

It amounts to the same thing: you need to insert NOP instructions.

Ian