[LLVMdev] CodeGen fails for CallInst with label

Edward Lee eslee3 at uiuc.edu
Sat Apr 19 12:04:13 PDT 2008

On Sat, Apr 19, 2008 at 1:27 PM, Chris Lattner <sabre at nondot.org> wrote:
> On Apr 19, 2008, at 1:30 AM, Edward Lee wrote:
>  > It seems like LLVM happily creates function calls that pass in labels
>  > but doesn't know how to emit them.
>  Yep, this isn't supported.  We can't quite enforce it as invalid at
>  this moment, but don't expect it to work.
That's a little bit disappointing for me. Is there some way in LLVM to
get the address of a label and put it in a register for use within
that function?

I'm using a special instruction that effectively branches to the value
in that register.

%tmp = label %label
br label %tmp

Except it doesn't behave like a (un)conditional branch of course;
otherwise, I would just use the standard LLVM BranchInst.


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