[LLVMdev] disabling combining load/stores in optimizer.

[Owen Anderson]

On Aug 4, 2009, at 12:19 AM, Alireza.Moshtaghi at microchip.com wrote:
> Well, for one thing, our port has no native operation other than 8-bit
> so it does not make sense to promote operations to higher precisions.
> Eventually all those operations will be lowered and the resulting code
> is most likely worse than if it was not promoted in the first place.  
> So
> I think it should be at the discretion of port to enable or disable  
> such
> optimizations as needed.

While that it a valid approach in general, it is completely at odds  
with the approach that the LLVM codebase has taken.  The general LLVM  
philosophy is that all optimizations should be as aggressive as  
possible at whatever they do, and it is then the responsibility of the  
target to lower what the optimizers produce into something legal for  
that machine.

Contravention of that design philosophy in a major portion of the  
optimization suite is unlikely at best, to be honest.

--Owen
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