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Re: Canonicalising truncated shift counts

> I don't think that'd be the right approach.  It seems odd for
> simplify_binary_operand to return null for a pair of operands
> if simplify_gen_subreg would keep one operand and change the
> value of the other.  This canonicalisation seems more in the
> spirit of things like
>
>       (minus ... (const_int X)) -> (plus ... (const_int -X))
>   and (mult ... (const_int 2<<X)) -> (ashift ... (const_int X))
>
> (especially the first).

Agreed.  Patch is OK if you rename the label to 'canonicalize_*' and put the 
new code either after the first affected case or the last affected case.

-- 
Eric Botcazou
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