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Re: [PATCH] PR target/68991: Add vector_memory_operand and "Bm" constraint


On Mon, Jan 04, 2016 at 03:25:48PM -0800, H.J. Lu wrote:
> LRA is fine.  I should use
> 
> (define_memory_constraint "Bm"
>   "@internal Vector memory operand."
>   (match_operand 0 "vector_memory_operand"))
> 
> instead of
> 
> (define_constraint "Bm"
>   "@internal Vector memory operand."
>   (match_operand 0 "vector_memory_operand"))

I don't think so.  At least the documentation says that
define_memory_constraint is for MEM constraints where if they are not
satisfied they can be made to satisfy by forcing the address into a
register.  But that is not the case here, if a MEM is misaligned, no
equivalent changes to the XEXP (mem, 0) will make it aligned.

	Jakub


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