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Re: builtin_bswap plus enhancements


> 
> Chris Lattner <clattner@apple.com> writes:
> 
> > Why not add bswap16 as well?
> 
> It should be unnecessary, since any attempt to express it should be
> picked up by the rot idiom recognizer, and the backends should then
> emit optimal code for constant-8 rots (and if that doesn't actually
> happen, we should rather fix that).

The other reason to add it is that some targets (PPC) actually have
an instruction which loads byte reversed half word (16bits) from memory.

-- Pinski


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