[LLVMdev] [PATCH] Emit rbit, clz on ARM for __builtin_ctz

Eli Friedman eli.friedman at gmail.com
Mon Jan 18 18:29:51 PST 2010

On Mon, Jan 18, 2010 at 5:10 PM, Jakob Stoklund Olesen <stoklund at 2pi.dk> wrote:
> On Jan 15, 2010, at 10:03 AM, Chris Lattner wrote:
>> When/if another target wants this, we could add a ISD::RBIT operation,
>> it doesn't need to be added at the llvm ir level,
> Blackfin can add with backwards carry, essentially doing
> (rbit (add (rbit a), (rbit b)))
> This is used for FFTs.
> I wasn't hoping to be able to pattern-match something so complicated.

Feel free to add target intrinsics where appropriate...


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