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Re: RFA: another patch to solve PR49154
Hans-Peter Nilsson <hp@bitrange.com> writes:
> Index: tm.texi.in
> ===================================================================
> --- tm.texi.in (revision 174376)
> +++ tm.texi.in (working copy)
> @@ -2327,6 +2327,11 @@ constraints is through machine-dependent
> You can define such letters to correspond to various classes, then use
> them in operand constraints.
>
> +You must define the narrowest register class for a register so that
> +class either has no subclasses, or that for some mode, the move cost
> +between registers within the class are cheaper than moving a register
> +in the class to or from memory (@pxref{Costs}).
> +
I fear this isn't true for some MIPS classes.
Richard