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|
(* TEST *)
type t = Leaf of int | Branch of t * t
type floatref = { mutable f : float }
let a = { f = 0.0 }
let rec allocate_lots m = function
| 0 -> Leaf m
| n -> Branch (allocate_lots m (n-1), allocate_lots (m+1) (n-1))
let measure f =
let a = Gc.minor_words () in
f ();
let c = Gc.minor_words () in
c -. a
let () =
let n = measure (fun () -> a.f <- Gc.minor_words ()) in
(* Gc.minor_words should not allocate, although bytecode
generally boxes the floats *)
assert (n < 10.);
if Sys.backend_type = Sys.Native then assert (n = 0.);
let n = measure (fun () -> Sys.opaque_identity (allocate_lots 42 10)) in
(* This should allocate > 3k words (varying slightly by unboxing) *)
assert (n > 3000.);
print_endline "ok"
|
