addExact intrinsic

Andrew Dinn adinn at
Tue Dec 10 07:31:53 PST 2013

On 10/12/13 15:22, Lindenmaier, Goetz wrote:
> I think the register mask must contain a single register, as you
> can not access the register in the Projection when encoding
> the instruction.  So you need to hard-code it in the ins_encode.
> The register allocation associates the allocated register 
> with the proj.

Ah, that is unfortunate. So, does that explain why x86 also has to use a
dedicated register? I assumed it was a restriction imposed by the x86
instruction the encoding was using.

> One hint: the rule with the immediate seems wrong. Why do you 
> pass the constant into as_Register()?

That is a mistake. The constant needs passing directly.


Andrew Dinn

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