x86: inline an LLVM IR function?

Sorry for what may possibly be a rather stupid question, but how on earth do you make LLC inline a function? I’ve got this code:

   attributes 0 = { alwaysinline nounwind }

   define internal i32 @lambda(i32 %a, i32 %x) #0 {
      %1 = add i32 %a, %x
      ret i32 %1

   define i32 @foo(i32 %a) nounwind {
      %1 = call i32 @lambda(i32 %a, i32 10)
      ret i32 %1

And no matter what I do, the function @lambda ends up being called with a call instruction.  I've tried with -O2, -O3, and with and without the alwaysinline attribute.
How do I get LLC or Clang to inline the above @lambda function?
Thanks in advance!

-- Mikael

You should use “opt” with -inline, or -O2/3 to optimise this.
llc only runs backend optimisations.

Thank you!

– Mikael