[LLVMdev] problem with sgt's on Sparc machine

[Bruno Cardoso Lopes]

Hi,

On Thu, Sep 15, 2011 at 3:15 PM, Christine Cheng <clcheng at stanford.edu> wrote:
> Hi guys,
>
> Thanks for the input. However, it seems that the code still produces the
> wrong output on a Sparc machine.
>
> My current llvm_print.bc code is:
> --------------------------------------------------------------------------------------------------
> ; MduleID = '<stdin>'
> target datalayout =
> "e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-n32"
> target triple = "sparc-unknown-linux"
>
> @P = global i32 1
> @dP = global i32 1
>
> @.str = private constant [4 x i8] c"%d\0A\00", align 1
>
> define i32 @main() nounwind {
>
> entry:
>     %. = load i32* @P, align 4
>     %t1 = tail call i32 (i8*, ...)* @printf(i8* noalias getelementptr
> inbounds ([4 x i8]* @.str, i32 0, i32 0), i32 %. ) nounwind
>     %d. = load i32* @dP, align 4
>     %t2 = tail call i32 (i8*, ...)* @printf(i8* noalias getelementptr
> inbounds ([4 x i8]* @.str, i32 0, i32 0), i32 %d. ) nounwind
>     %0 = icmp sgt i32 %., 0
>   %1 = tail call i32 (i8*, ...)* @printf(i8* noalias getelementptr inbounds
> ([4 x i8]* @.str, i32 0, i32 0), i1 %0 ) nounwind
>     %2 = icmp sgt i32 %d., 0
>     %3 = tail call i32 (i8*, ...)* @printf(i8* noalias getelementptr
> inbounds ([4 x i8]* @.str, i32 0, i32 0), i1 %2 ) nounwind
>     %t3 = icmp eq i32 %d., %d.
>     %t4 = tail call i32 (i8*, ...)* @printf(i8* noalias getelementptr
> inbounds ([4 x i8]* @.str, i32 0, i32 0), i1 %t3 ) nounwind
>     %4 = icmp sgt i32 1, 0
>     %5 = icmp sgt i32 1, 0
>     %6 = tail call i32 (i8*, ...)* @printf(i8* noalias getelementptr
> inbounds ([4 x i8]* @.str, i32 0, i32 0), i1 %4 ) nounwind
>     %7 = tail call i32 (i8*, ...)* @printf(i8* noalias getelementptr
> inbounds ([4 x i8]* @.str, i32 0, i32 0), i1 %5 ) nounwind
>   ret i32 undef
> }
>
> declare i32 @printf(i8* nocapture, ...) nounwind
>
> --------------------------------------------------------------------------------------------------
>
> The output is still:
>
> 1
> 1
> 0
> 0
> 1
> 1
> 1
>
> which should be all ones. Is there a sign error somewhere?

Please file a bug to llvm.org/bugs
I don't know of anyone working on Sparc right now, so if you could dig
and find out what llvm is generating wrong, someone may provide a fix
faster. Or if you're willing to right a patch that would be even
better! :)

-- 
Bruno Cardoso Lopes
http://www.brunocardoso.cc