unikernel/duniverse/ocaml_intrinsics_kernel/test/dune

@@ -0,0 +1,13 @@
+(library
+ (name ocaml_intrinsics_kernel_test)
+ (preprocessor_deps config.h)
+ (libraries ocaml_intrinsics_kernel ppx_bench.runtime-lib ppx_expect.runtime
+   ppx_module_timer.runtime)
+ (preprocess
+  (pps ppx_jane ppx_optcomp)))
+
+(rule
+ (targets config.h)
+ (deps)
+ (action
+  (bash "cp %{lib:jst-config:config.h} .")))

unikernel/duniverse/ocaml_intrinsics_kernel/test/test_clz.ml

@@ -0,0 +1,195 @@
+[%%import "config.h"]
+
+open Base
+open Stdio
+module I = Ocaml_intrinsics_kernel
+
+let test ~op ~op_name ~to_string x = printf "%s %s = %d\n" op_name (to_string x) (op x)
+
+let%expect_test "clz int64" =
+  let open Int64 in
+  let numbers =
+    [ 0L (* Int.num_bits *)
+    ; 1L (* Int.num_bits - 1 *)
+    ; 7L (* Int.num_bits - 3  *)
+    ; max_value
+    ; min_value
+    ; -1L
+    ]
+  in
+  let f =
+    test ~op:I.Int64.count_leading_zeros ~op_name:"clz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    clz 0x0 = 64
+    clz 0x1 = 63
+    clz 0x7 = 61
+    clz 0x7fff_ffff_ffff_ffff = 1
+    clz -0x8000_0000_0000_0000 = 0
+    clz -0x1 = 0
+    |}]
+;;
+
+let%expect_test "clz int32" =
+  let open Int32 in
+  let numbers =
+    [ 0l (* Int.num_bits *)
+    ; 1l (* Int.num_bits - 1 *)
+    ; 7l (* Int.num_bits - 3  *)
+    ; max_value
+    ; min_value
+    ; -1l
+    ]
+  in
+  let f =
+    test ~op:I.Int32.count_leading_zeros ~op_name:"clz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    clz 0x0 = 32
+    clz 0x1 = 31
+    clz 0x7 = 29
+    clz 0x7fff_ffff = 1
+    clz -0x8000_0000 = 0
+    clz -0x1 = 0
+    |}]
+;;
+
+[%%ifdef JSC_ARCH_SIXTYFOUR]
+
+let%expect_test "clz int" =
+  let open Int in
+  let numbers =
+    [ 0 (* Int.num_bits *)
+    ; 1 (* Int.num_bits - 1 *)
+    ; 7 (* Int.num_bits - 3  *)
+    ; max_value
+    ; min_value
+    ; -1
+    ]
+  in
+  let f =
+    test ~op:I.Int.count_leading_zeros ~op_name:"clz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    clz 0x0 = 63
+    clz 0x1 = 62
+    clz 0x7 = 60
+    clz 0x3fff_ffff_ffff_ffff = 1
+    clz -0x4000_0000_0000_0000 = 0
+    clz -0x1 = 0
+    |}];
+  let f =
+    test ~op:I.Int.count_leading_zeros2 ~op_name:"clz2" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    clz2 0x0 = 63
+    clz2 0x1 = 62
+    clz2 0x7 = 60
+    clz2 0x3fff_ffff_ffff_ffff = 1
+    clz2 -0x4000_0000_0000_0000 = 0
+    clz2 -0x1 = 0
+    |}]
+;;
+
+let%expect_test "clz nativeint" =
+  let open Nativeint in
+  let numbers =
+    [ 0n (* Int.num_bits *)
+    ; 1n (* Int.num_bits - 1 *)
+    ; 7n (* Int.num_bits - 3  *)
+    ; max_value
+    ; min_value
+    ; -1n
+    ]
+  in
+  let f =
+    test ~op:I.Nativeint.count_leading_zeros ~op_name:"clz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    clz 0x0 = 64
+    clz 0x1 = 63
+    clz 0x7 = 61
+    clz 0x7fff_ffff_ffff_ffff = 1
+    clz -0x8000_0000_0000_0000 = 0
+    clz -0x1 = 0
+    |}]
+;;
+
+[%%else]
+
+let%expect_test "clz int" =
+  let open Int in
+  let numbers =
+    [ 0 (* Int.num_bits *)
+    ; 1 (* Int.num_bits - 1 *)
+    ; 7 (* Int.num_bits - 3  *)
+    ; max_value
+    ; min_value
+    ; -1
+    ]
+  in
+  let f =
+    test ~op:I.Int.count_leading_zeros ~op_name:"clz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    clz 0x0 = 31
+    clz 0x1 = 30
+    clz 0x7 = 28
+    clz 0x3fff_ffff = 1
+    clz -0x4000_0000 = 0
+    clz -0x1 = 0
+    |}];
+  let f =
+    test ~op:I.Int.count_leading_zeros2 ~op_name:"clz2" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    clz2 0x0 = 31
+    clz2 0x1 = 30
+    clz2 0x7 = 28
+    clz2 0x3fff_ffff = 1
+    clz2 -0x4000_0000 = 0
+    clz2 -0x1 = 0
+    |}]
+;;
+
+let%expect_test "clz nativeint" =
+  let open Nativeint in
+  let numbers =
+    [ 0n (* Int.num_bits *)
+    ; 1n (* Int.num_bits - 1 *)
+    ; 7n (* Int.num_bits - 3  *)
+    ; max_value
+    ; min_value
+    ; -1n
+    ]
+  in
+  let f =
+    test ~op:I.Nativeint.count_leading_zeros ~op_name:"clz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    clz 0x0 = 32
+    clz 0x1 = 31
+    clz 0x7 = 29
+    clz 0x7fff_ffff = 1
+    clz -0x8000_0000 = 0
+    clz -0x1 = 0
+    |}]
+;;
+
+[%%endif]

unikernel/duniverse/ocaml_intrinsics_kernel/test/test_clz.mli

@@ -0,0 +1 @@
+(*_ This signature is deliberately empty. *)

unikernel/duniverse/ocaml_intrinsics_kernel/test/test_csel.ml

@@ -0,0 +1,197 @@
+open Base
+open Stdio
+module I = Ocaml_intrinsics_kernel.Conditional
+
+let%expect_test "csel int" =
+  let inputs = [ 0; 1; 4; 6; 5 ] in
+  List.iter inputs ~f:(fun a ->
+    let expect = if a % 2 = 0 then a else a + 1 in
+    let actual = I.select_value (a % 2 = 0) a (a + 1) in
+    printf "%d %d\n" expect actual);
+  [%expect {|
+    0 0
+    2 2
+    4 4
+    6 6
+    6 6
+    |}]
+;;
+
+let%expect_test "csel max int value" =
+  let inputs = [ 0, 1; 4, 5 ] in
+  List.iter inputs ~f:(fun (a, b) ->
+    let expect = if a > b then a else b in
+    let actual = I.select_value (a > b) a b in
+    printf "%d %d\n" expect actual);
+  [%expect {|
+    1 1
+    5 5
+    |}]
+;;
+
+let%expect_test "csel max float value" =
+  let inputs = [ 0.5, Float.neg_infinity; 0.0, 0.1; Float.nan, 5.0 ] in
+  List.iter inputs ~f:(fun (a, b) ->
+    let expect = if Float.(a > b) then a else b in
+    let actual = I.select_value Float.(a > b) a b in
+    printf "%f %f\n" expect actual);
+  [%expect {|
+    0.500000 0.500000
+    0.100000 0.100000
+    5.000000 5.000000
+    |}]
+;;
+
+let%expect_test "csel max int untagged" =
+  let inputs = [ 0, 1; 4, 5 ] in
+  List.iter inputs ~f:(fun (a, b) ->
+    let expect = if a > b then a else b in
+    let actual = I.select_int (a > b) a b in
+    printf "%d %d\n" expect actual);
+  [%expect {|
+    1 1
+    5 5
+    |}]
+;;
+
+let%expect_test "csel max int64 unboxed" =
+  let inputs = [ 0L, 1L; 4L, 5L; Int64.max_value, Int64.min_value ] in
+  List.iter inputs ~f:(fun (a, b) ->
+    let expect = if Int64.(a > b) then a else b in
+    let actual = I.select_int64 Int64.(a > b) a b in
+    printf "%Ld %Ld\n" expect actual);
+  [%expect {|
+    1 1
+    5 5
+    9223372036854775807 9223372036854775807
+    |}]
+;;
+
+let%expect_test "csel max int32 unboxed" =
+  let inputs = [ 0l, 1l; 4l, 5l; Int32.max_value, Int32.min_value ] in
+  List.iter inputs ~f:(fun (a, b) ->
+    let expect = if Int32.(a > b) then a else b in
+    let actual = I.select_int32 Int32.(a > b) a b in
+    printf "%ld %ld\n" expect actual);
+  [%expect {|
+    1 1
+    5 5
+    2147483647 2147483647
+    |}]
+;;
+
+[%%import "config.h"]
+[%%ifdef JSC_ARCH_SIXTYFOUR]
+
+let%expect_test "csel max nativeint unboxed" =
+  let inputs = [ 0n, 1n; 4n, 5n; Nativeint.max_value, Nativeint.min_value ] in
+  List.iter inputs ~f:(fun (a, b) ->
+    let expect = if Nativeint.(a > b) then a else b in
+    let actual = I.select_nativeint Nativeint.(a > b) a b in
+    printf "%nd %nd\n" expect actual);
+  [%expect {|
+    1 1
+    5 5
+    9223372036854775807 9223372036854775807
+    |}]
+;;
+
+[%%else]
+
+let%expect_test "csel max nativeint unboxed" =
+  let inputs = [ 0n, 1n; 4n, 5n; Nativeint.max_value, Nativeint.min_value ] in
+  List.iter inputs ~f:(fun (a, b) ->
+    let expect = if Nativeint.(a > b) then a else b in
+    let actual = I.select_nativeint Nativeint.(a > b) a b in
+    printf "%nd %nd\n" expect actual);
+  [%expect {|
+    1 1
+    5 5
+    2147483647 2147483647
+    |}]
+;;
+
+[%%endif]
+
+let%expect_test "csel sideffects" =
+  let inputs = [ 0, 1; 5, 4 ] in
+  List.iter inputs ~f:(fun (a, b) ->
+    let expect =
+      if a > b
+      then (
+        printf "hello 0\n";
+        a)
+      else (
+        printf "world 0\n";
+        b)
+    in
+    let actual =
+      I.select_value
+        (a > b)
+        (printf "hello 1\n";
+         a)
+        (printf "world 1\n";
+         b)
+    in
+    printf "%d %d\n" expect actual);
+  [%expect
+    {|
+    world 0
+    world 1
+    hello 1
+    1 1
+    hello 0
+    world 1
+    hello 1
+    5 5
+    |}]
+;;
+
+let%expect_test "min extra moves" =
+  (* Currently [min] emits extra moves:
+   *
+   * actual:
+   *
+   * camlT__min_266:
+   *   movq	%rax, %rdi
+   *   movq	%rbx, %rax
+   *   cmpq	%rax, %rdi
+   *   cmovl	%rdi, %rax
+   *   ret
+   *
+   * [min2] is
+   *
+   * camlT__min2_273:
+   *    cmpq	%rax, %rbx
+   *    cmovl	%rbx, %rax
+   * 	ret
+   * ret *)
+  let[@inline never] min (x : int) (y : int) = I.select_value (x < y) x y in
+  let[@inline never] min2 (x : int) (y : int) = I.select_value (y < x) y x in
+  let inputs = [ 0, 1; 5, 4 ] in
+  List.iter inputs ~f:(fun (a, b) ->
+    printf "%d " (min a b);
+    printf "%d\n" (min2 a b));
+  [%expect {|
+    0 0
+    4 4
+    |}]
+;;
+
+let%expect_test "float deadcode" =
+  (* Currently [nop_float] emits extra loads, because there is no dead code elimination
+   *    after register allocation:
+   *
+   *    camlT__nop_float_292:
+   *      movsd	(%rbx), %xmm0
+   *      movsd	(%rax), %xmm1
+   *      ret *)
+  let[@inline never] nop_float (x : float) (y : float) : float =
+    I.select_value Float.(x > y) x x
+  in
+  let inputs =
+    [ 0.5, Float.neg_infinity; 0.0, 0.1; Float.nan, 5.0; Float.infinity, -0.0 ]
+  in
+  List.iter inputs ~f:(fun (a, b) -> printf "%f " (nop_float a b));
+  [%expect {| 0.500000 0.000000 nan inf |}]
+;;

unikernel/duniverse/ocaml_intrinsics_kernel/test/test_csel.mli

@@ -0,0 +1 @@
+(* blank *)

unikernel/duniverse/ocaml_intrinsics_kernel/test/test_ctz.ml

@@ -0,0 +1,144 @@
+[%%import "config.h"]
+
+open Base
+open Stdio
+module I = Ocaml_intrinsics_kernel
+
+let test ~op ~op_name ~to_string x = printf "%s %s = %d\n" op_name (to_string x) (op x)
+let numbers = [ 0 (* Int.num_bits *); 1; 7; 2; 4; 12; 18; -1 ]
+
+let%expect_test "ctz int64" =
+  let open Int64 in
+  let numbers = List.map numbers ~f:of_int in
+  let f =
+    test ~op:I.Int64.count_trailing_zeros ~op_name:"ctz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f (max_value :: min_value :: numbers);
+  [%expect
+    {|
+    ctz 0x7fff_ffff_ffff_ffff = 0
+    ctz -0x8000_0000_0000_0000 = 63
+    ctz 0x0 = 64
+    ctz 0x1 = 0
+    ctz 0x7 = 0
+    ctz 0x2 = 1
+    ctz 0x4 = 2
+    ctz 0xc = 2
+    ctz 0x12 = 1
+    ctz -0x1 = 0
+    |}]
+;;
+
+let%expect_test "ctz int32" =
+  let open Int32 in
+  let numbers = List.map numbers ~f:of_int_trunc in
+  let f =
+    test ~op:I.Int32.count_trailing_zeros ~op_name:"ctz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f (max_value :: min_value :: numbers);
+  [%expect
+    {|
+    ctz 0x7fff_ffff = 0
+    ctz -0x8000_0000 = 31
+    ctz 0x0 = 32
+    ctz 0x1 = 0
+    ctz 0x7 = 0
+    ctz 0x2 = 1
+    ctz 0x4 = 2
+    ctz 0xc = 2
+    ctz 0x12 = 1
+    ctz -0x1 = 0
+    |}]
+;;
+
+[%%ifdef JSC_ARCH_SIXTYFOUR]
+
+let%expect_test "ctz int" =
+  let open Int in
+  let f =
+    test ~op:I.Int.count_trailing_zeros ~op_name:"ctz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f (max_value :: min_value :: numbers);
+  [%expect
+    {|
+    ctz 0x3fff_ffff_ffff_ffff = 0
+    ctz -0x4000_0000_0000_0000 = 62
+    ctz 0x0 = 63
+    ctz 0x1 = 0
+    ctz 0x7 = 0
+    ctz 0x2 = 1
+    ctz 0x4 = 2
+    ctz 0xc = 2
+    ctz 0x12 = 1
+    ctz -0x1 = 0
+    |}]
+;;
+
+let%expect_test "ctz nativeint" =
+  let open Nativeint in
+  let numbers = List.map numbers ~f:of_int in
+  let f =
+    test ~op:I.Nativeint.count_trailing_zeros ~op_name:"ctz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f (max_value :: min_value :: numbers);
+  [%expect
+    {|
+    ctz 0x7fff_ffff_ffff_ffff = 0
+    ctz -0x8000_0000_0000_0000 = 63
+    ctz 0x0 = 64
+    ctz 0x1 = 0
+    ctz 0x7 = 0
+    ctz 0x2 = 1
+    ctz 0x4 = 2
+    ctz 0xc = 2
+    ctz 0x12 = 1
+    ctz -0x1 = 0
+    |}]
+;;
+
+[%%else]
+
+let%expect_test "ctz int" =
+  let open Int in
+  let f =
+    test ~op:I.Int.count_trailing_zeros ~op_name:"ctz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f (max_value :: min_value :: numbers);
+  [%expect
+    {|
+    ctz 0x3fff_ffff = 0
+    ctz -0x4000_0000 = 30
+    ctz 0x0 = 31
+    ctz 0x1 = 0
+    ctz 0x7 = 0
+    ctz 0x2 = 1
+    ctz 0x4 = 2
+    ctz 0xc = 2
+    ctz 0x12 = 1
+    ctz -0x1 = 0
+    |}]
+;;
+
+let%expect_test "ctz nativeint" =
+  let open Nativeint in
+  let numbers = List.map numbers ~f:of_int in
+  let f =
+    test ~op:I.Nativeint.count_trailing_zeros ~op_name:"ctz" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f (max_value :: min_value :: numbers);
+  [%expect
+    {|
+    ctz 0x7fff_ffff = 0
+    ctz -0x8000_0000 = 31
+    ctz 0x0 = 32
+    ctz 0x1 = 0
+    ctz 0x7 = 0
+    ctz 0x2 = 1
+    ctz 0x4 = 2
+    ctz 0xc = 2
+    ctz 0x12 = 1
+    ctz -0x1 = 0
+    |}]
+;;
+
+[%%endif]

unikernel/duniverse/ocaml_intrinsics_kernel/test/test_ctz.mli

@@ -0,0 +1 @@
+(*_ This signature is deliberately empty. *)

unikernel/duniverse/ocaml_intrinsics_kernel/test/test_float.ml

@@ -0,0 +1,41 @@
+open! Base
+open! Stdio
+module I = Ocaml_intrinsics_kernel.Float
+
+let%expect_test "min and max" =
+  let args =
+    [ 0., 1.
+    ; 1., 0.
+    ; Float.neg_infinity, Float.infinity
+    ; Float.infinity, Float.neg_infinity
+    ; -0., 0.
+    ; 0., -0.
+    ; Float.nan, 0.
+    ; 0., Float.nan
+    ]
+  in
+  List.iter args ~f:(fun (x, y) -> printf "min %.19g %.19g = %.19g\n" x y (I.min x y));
+  [%expect
+    {|
+    min 0 1 = 0
+    min 1 0 = 0
+    min -inf inf = -inf
+    min inf -inf = -inf
+    min -0 0 = 0
+    min 0 -0 = -0
+    min nan 0 = 0
+    min 0 nan = nan
+    |}];
+  List.iter args ~f:(fun (x, y) -> printf "max %.19g %.19g = %.19g\n" x y (I.max x y));
+  [%expect
+    {|
+    max 0 1 = 1
+    max 1 0 = 1
+    max -inf inf = inf
+    max inf -inf = inf
+    max -0 0 = 0
+    max 0 -0 = -0
+    max nan 0 = 0
+    max 0 nan = nan
+    |}]
+;;

unikernel/duniverse/ocaml_intrinsics_kernel/test/test_float.mli

@@ -0,0 +1 @@
+(*_ This signature is deliberately empty. *)

unikernel/duniverse/ocaml_intrinsics_kernel/test/test_popcnt.ml

@@ -0,0 +1,159 @@
+[%%import "config.h"]
+
+open Base
+open Stdio
+module I = Ocaml_intrinsics_kernel
+
+let test ~op ~op_name ~to_string x = printf "%s %s = %d\n" op_name (to_string x) (op x)
+
+let%expect_test "popcnt int64" =
+  let open Int64 in
+  let numbers = [ 0L; 1L; 7L; max_value; min_value; -1L ] in
+  let f =
+    test ~op:I.Int64.count_set_bits ~op_name:"popcnt" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    popcnt 0x0 = 0
+    popcnt 0x1 = 1
+    popcnt 0x7 = 3
+    popcnt 0x7fff_ffff_ffff_ffff = 63
+    popcnt -0x8000_0000_0000_0000 = 1
+    popcnt -0x1 = 64
+    |}]
+;;
+
+let%expect_test "popcnt int32" =
+  let open Int32 in
+  let numbers = [ 0l; 1l; 7l; max_value; min_value; -1l ] in
+  let f =
+    test ~op:I.Int32.count_set_bits ~op_name:"popcnt" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    popcnt 0x0 = 0
+    popcnt 0x1 = 1
+    popcnt 0x7 = 3
+    popcnt 0x7fff_ffff = 31
+    popcnt -0x8000_0000 = 1
+    popcnt -0x1 = 32
+    |}]
+;;
+
+[%%ifdef JSC_ARCH_SIXTYFOUR]
+
+let%expect_test "popcnt int" =
+  let open Int in
+  let numbers =
+    [ 0
+    ; 1
+    ; 7
+    ; max_value (* Int.num_bits - 1 *)
+    ; min_value (* 1 *)
+    ; -1 (* Int.num_bits *)
+    ]
+  in
+  let f = test ~op:I.Int.count_set_bits ~op_name:"popcnt" ~to_string:Hex.to_string_hum in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    popcnt 0x0 = 0
+    popcnt 0x1 = 1
+    popcnt 0x7 = 3
+    popcnt 0x3fff_ffff_ffff_ffff = 62
+    popcnt -0x4000_0000_0000_0000 = 1
+    popcnt -0x1 = 63
+    |}];
+  let f =
+    test ~op:I.Int.count_set_bits2 ~op_name:"popcnt2" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    popcnt2 0x0 = 0
+    popcnt2 0x1 = 1
+    popcnt2 0x7 = 3
+    popcnt2 0x3fff_ffff_ffff_ffff = 62
+    popcnt2 -0x4000_0000_0000_0000 = 1
+    popcnt2 -0x1 = 63
+    |}]
+;;
+
+let%expect_test "popcnt nativeint" =
+  let open Nativeint in
+  let numbers = [ 0n; 1n; 7n; max_value; min_value; -1n ] in
+  let f =
+    test ~op:I.Nativeint.count_set_bits ~op_name:"popcnt" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    popcnt 0x0 = 0
+    popcnt 0x1 = 1
+    popcnt 0x7 = 3
+    popcnt 0x7fff_ffff_ffff_ffff = 63
+    popcnt -0x8000_0000_0000_0000 = 1
+    popcnt -0x1 = 64
+    |}]
+;;
+
+[%%else]
+
+let%expect_test "popcnt int" =
+  let open Int in
+  let numbers =
+    [ 0
+    ; 1
+    ; 7
+    ; max_value (* Int.num_bits - 1 *)
+    ; min_value (* 1 *)
+    ; -1 (* Int.num_bits *)
+    ]
+  in
+  let f = test ~op:I.Int.count_set_bits ~op_name:"popcnt" ~to_string:Hex.to_string_hum in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    popcnt 0x0 = 0
+    popcnt 0x1 = 1
+    popcnt 0x7 = 3
+    popcnt 0x3fff_ffff = 30
+    popcnt -0x4000_0000 = 1
+    popcnt -0x1 = 31
+    |}];
+  let f =
+    test ~op:I.Int.count_set_bits2 ~op_name:"popcnt2" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    popcnt2 0x0 = 0
+    popcnt2 0x1 = 1
+    popcnt2 0x7 = 3
+    popcnt2 0x3fff_ffff = 30
+    popcnt2 -0x4000_0000 = 1
+    popcnt2 -0x1 = 31
+    |}]
+;;
+
+let%expect_test "popcnt nativeint" =
+  let open Nativeint in
+  let numbers = [ 0n; 1n; 7n; max_value; min_value; -1n ] in
+  let f =
+    test ~op:I.Nativeint.count_set_bits ~op_name:"popcnt" ~to_string:Hex.to_string_hum
+  in
+  List.iter ~f numbers;
+  [%expect
+    {|
+    popcnt 0x0 = 0
+    popcnt 0x1 = 1
+    popcnt 0x7 = 3
+    popcnt 0x7fff_ffff = 31
+    popcnt -0x8000_0000 = 1
+    popcnt -0x1 = 32
+    |}]
+;;
+
+[%%endif]

unikernel/duniverse/ocaml_intrinsics_kernel/test/test_popcnt.mli

@@ -0,0 +1 @@
+(*_ This signature is deliberately empty. *)