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Re: powerpc & unaligned block moves with fp registers


>>>>> Mark Mitchell writes:

Mark> I would prefer to see GCC just ask the back end "How do you want to
Mark> perform a memory-to-memory copy of thus and such many bits, knowing
Mark> thus and such about the current alignment of the memory?"

	And I consider BLKmode move (movstrsi, etc.) the way to do that.
It already provides an alignment and number of bytes.  On PowerPC, BLKmove
chooses the most efficient method, including using DImode.

	One could call BLKmode move always, but my model was using
SLOW_UNALIGNED_ACCESS to determine when the backend considred things
"complicated" or "non-obvious" that the common code should punt to BLKmode
move.

David


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