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Using OCaml's run-time from LLVM-generated native code

Jon Harrop
- Alain Frisch
  - Jon Harrop
    - Alain Frisch
      - Jon Harrop
        
        Alain Frisch
        
        Jon Harrop
        
        Alain Frisch
        
        Florent Monnier

Date:	-- (:)
From:	Florent Monnier <fmonnier@l...>
Subject:	Re: [Caml-list] Using OCaml's run-time from LLVM-generated native code

Hi,

Jon Harrop wrote:
> int apply(int n) {
>   CAMLparam0();
>   CAMLlocal2(nv, fibn);
>   nv = copy_int64(n);
>   fibn = fib(nv);
>   caml_gc_full_major(0);
>   CAMLreturn(Int64_val(fib(nv)));
> }
>
> Is that correct?
>
> Next, this C code is 4x slower than the ocamlopt-generated equivalent. What 
> can be done to improve its performance without leaving C?

I don't know if it is a typo from you, or if it is me that don't understand 
the code, but it seems that fib(nv) is computed twice.
Shouldn't the second one be replaced by fibn, the result of the first one?