1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
|
(* TEST *)
let[@inline never] float_unboxing s f =
let x = Sys.opaque_identity (s +. 1.) in
let mw1 = Gc.minor_words () in
let mw2 = Gc.minor_words () in
f x;
let mw3 = Gc.minor_words () in
Printf.printf "unbox: %.0f\n" ((mw3 -. mw2) -. (mw2 -. mw1))
let[@inline never] lifetimes () =
let final = ref false in
let go () =
let r = ref 42 in
Gc.finalise (fun _ -> final := true) r;
let f1 = !final in
Gc.full_major ();
let f2 = !final in
ignore (Sys.opaque_identity r);
(f1, f2) in
let (f1, f2) = go () in
Gc.full_major ();
let f3 = !final in
Printf.printf "lifetime: %b %b %b\n" f1 f2 f3
let[@inline never] dead_alloc a =
let mw1 = Gc.minor_words () in
let mw2 = Gc.minor_words () in
ignore (Sys.opaque_identity (a, a));
let mw3 = Gc.minor_words () in
Printf.printf "dead: %.0f\n" ((mw3 -. mw2) -. (mw2 -. mw1))
let () =
float_unboxing 50. (fun _ -> ());
lifetimes ();
dead_alloc 10
|
