[llvm-commits] [PATCH] ARM: Custom lower scalar ctpop

[Pete Couperus]

Hello,

I think you are right, probably vcnt and a couple of vaddl's.  I will verify, and resubmit shortly.

Pete


Evan Cheng <evan.cheng at apple.com> wrote:

>This seems wrong to me. I think a scalar popcount should be 3-4 instructions. Owen, I believe you know the right code sequence for popcount with vcnt. What do you suggest?
>
>Evan
>
>On Dec 8, 2012, at 9:06 AM, Pete Couperus <pjcoup at gmail.com> wrote:
>
>> Hello,
>> 
>> Forgot the test case.  Reattached with test case.
>> 
>> Pete
>> 
>> 
>> On Sat, Dec 8, 2012 at 8:39 AM, Pete Couperus <pjcoup at gmail.com> wrote:
>>> Hello,
>>> 
>>> This patch builds on the vector support for ARM/NEON ctpop lowering
>>> (r169325) to give i32/i64 custom lowering.
>>> It does not tie into the ctpop idiom recognition, as that patch seems
>>> to being discussed right now.
>>> Please review!
>>> Thanks!
>>> 
>>> Pete
>> <0001-scalar-ctpop.diff>