[LLVMdev] Questions about instruction selection and instruction definitions

Chris Lattner sabre at nondot.org
Thu Oct 5 09:46:36 PDT 2006


On Thu, 5 Oct 2006, Roman Levenstein wrote:
>> Check out how the sparc or powerpc backends handle this.  They lower
>> to a
>> select_cc pseudo-op that expands to an if/then/else control flow.
>
> Thanks! The hint about a pseudo-op was really good. After I realized how 
> it works, I started the implementation of SELECT_CC using this approach. 
> Hopefully, I can finish it today.

Great.

> Chris, may be you could provide some feedback about other questions
> from the original mail? In particular about the register classes and
> subclasses and about restrictions related to multiclasses? I'd be very
> grateful.

Can you resend it?  I apparently didn't get it or deleted it or something. 
I just saw the response to it.  Thanks,

-Chris

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