llvm dev - Jan 2018 - wasm: Bad codegen for i8 comparison

(Currently using a build from november but I didn't see any commit that 
could fix this for wasm); With the wasm backend,


  %2 = icmp sgt i8 %0, -1

becomes:
         i32.const       $4=, 255
         i32.const       $2=, 255
         i32.and         $3=, $0, $2
         i32.const       $5=, 255
         i32.and         $6=, $4, $5
         i32.gt_s        $7=, $3, $6

Which essentially does (arg & 0xff) > (0xff & 0xff) (if I read it 
correctly) and seems to always result in false.

Full testcase:
https://gist.github.com/carlokok/579b7793465cd0299cf4c609c569f559

Hello,

Can you check whether your build includes r317710
<https://llvm.org/svn/llvm-project/llvm/trunk at 317710>?

Thanks,

Dan


On Thu, Jan 11, 2018 at 12:51 AM, Carlo Kok via llvm-dev <
llvm-dev at lists.llvm.org> wrote:
> (Currently using a build from november but I didn't see any commit that
> could fix this for wasm); With the wasm backend,
>
>
>  %2 = icmp sgt i8 %0, -1
>
> becomes:
>         i32.const       $4=, 255
>         i32.const       $2=, 255
>         i32.and         $3=, $0, $2
>         i32.const       $5=, 255
>         i32.and         $6=, $4, $5
>         i32.gt_s        $7=, $3, $6
>
> Which essentially does (arg & 0xff) > (0xff & 0xff) (if I read
it
> correctly) and seems to always result in false.
>
> Full testcase:
> https://gist.github.com/carlokok/579b7793465cd0299cf4c609c569f559
> _______________________________________________
> LLVM Developers mailing list
> llvm-dev at lists.llvm.org
> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-dev
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL:
<http://lists.llvm.org/pipermail/llvm-dev/attachments/20180111/c929cb7a/attachment.html>

On 2018-01-11 18:53, Dan Gohman wrote:
> Hello,
> 
> Can you check whether your build includes r317710 [3]?
> 
> Thanks,
> 
> Dan
> 
Hi,

thanks I missed that one. I'll update and see if that fixes it.

Op 11-1-2018 om 18:53 schreef Dan Gohman:
> Hello,
> 
> Can you check whether your build includes r317710 
<https://llvm.org/svn/llvm-project/llvm/trunk at 317710>?
> 
> Thanks,
> 
> Dan
This completely fixes it. Thanks!