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Re: [PATCH][ARM] Fix broken shift patterns


> Oh, I forgot to say, I don't understand why the "rotate" operator is
> special cased?
> 
> If I understand it correctly, the effect of the (existing) rotate is
> both to check the constant range, AND to disallow registers as the shift
> amount. This difference has no effect on Thumb, but might cause ARM mode
> some troubles?
> 
> Is this likely to be deliberate, or an oversight? I can't see any reason
> in the ARM ARM why this should be the case.

Deliberate. ARM only has rotatert (which for immediate operands can be 
substituted at assembly generation time).

Paul


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