spec: bitwise operations (bitwise-and/or/xor/not, arithmetic-shift, bit-count, integer-length)

OCaml: land/lor/lxor/lnot/lsl/asr in sx_primitives.ml
JS: & | ^ ~ << >> with Kernighan popcount and Math.clz32 for integer-length
spec/primitives.sx: stdlib.bitwise module with 7 entries
26 tests, 158 assertions, all pass OCaml+JS

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

hosts/javascript/platform.py

@@ -1309,6 +1309,27 @@ PRIMITIVES_JS_MODULES: dict[str, str] = {
     return NIL;
   };
 ''',
+
+    "stdlib.bitwise": '''
+  // stdlib.bitwise
+  PRIMITIVES["bitwise-and"] = function(a, b) { return (a & b) | 0; };
+  PRIMITIVES["bitwise-or"]  = function(a, b) { return (a | b) | 0; };
+  PRIMITIVES["bitwise-xor"] = function(a, b) { return (a ^ b) | 0; };
+  PRIMITIVES["bitwise-not"] = function(a)    { return ~a; };
+  PRIMITIVES["arithmetic-shift"] = function(a, count) {
+    return count >= 0 ? (a << count) | 0 : a >> (-count);
+  };
+  PRIMITIVES["bit-count"] = function(a) {
+    var n = Math.abs(a) >>> 0;
+    n = n - ((n >> 1) & 0x55555555);
+    n = (n & 0x33333333) + ((n >> 2) & 0x33333333);
+    return (((n + (n >> 4)) & 0x0f0f0f0f) * 0x01010101) >>> 24;
+  };
+  PRIMITIVES["integer-length"] = function(a) {
+    if (a === 0) return 0;
+    return 32 - Math.clz32(Math.abs(a));
+  };
+''',
 }
 # Modules to include by default (all)
 _ALL_JS_MODULES = list(PRIMITIVES_JS_MODULES.keys())

hosts/ocaml/lib/sx_primitives.ml

@@ -2007,4 +2007,49 @@ let () =
     | [rx] ->
       let (_, _, flags) = regex_of_value rx in
       String flags
-    | _ -> raise (Eval_error "regex-flags: (regex)"))
+    | _ -> raise (Eval_error "regex-flags: (regex)"));
+
+  (* Bitwise operations *)
+  register "bitwise-and" (fun args ->
+    match args with
+    | [Integer a; Integer b] -> Integer (a land b)
+    | _ -> raise (Eval_error "bitwise-and: expected (integer integer)"));
+  register "bitwise-or" (fun args ->
+    match args with
+    | [Integer a; Integer b] -> Integer (a lor b)
+    | _ -> raise (Eval_error "bitwise-or: expected (integer integer)"));
+  register "bitwise-xor" (fun args ->
+    match args with
+    | [Integer a; Integer b] -> Integer (a lxor b)
+    | _ -> raise (Eval_error "bitwise-xor: expected (integer integer)"));
+  register "bitwise-not" (fun args ->
+    match args with
+    | [Integer a] -> Integer (lnot a)
+    | _ -> raise (Eval_error "bitwise-not: expected (integer)"));
+  register "arithmetic-shift" (fun args ->
+    match args with
+    | [Integer a; Integer count] ->
+      Integer (if count >= 0 then a lsl count else a asr (-count))
+    | _ -> raise (Eval_error "arithmetic-shift: expected (integer integer)"));
+  register "bit-count" (fun args ->
+    match args with
+    | [Integer a] ->
+      let n = ref (abs a) in
+      let c = ref 0 in
+      while !n <> 0 do
+        c := !c + (!n land 1);
+        n := !n lsr 1
+      done;
+      Integer !c
+    | _ -> raise (Eval_error "bit-count: expected (integer)"));
+  register "integer-length" (fun args ->
+    match args with
+    | [Integer a] ->
+      let n = ref (abs a) in
+      let bits = ref 0 in
+      while !n <> 0 do
+        incr bits;
+        n := !n lsr 1
+      done;
+      Integer !bits
+    | _ -> raise (Eval_error "integer-length: expected (integer)"))

shared/static/scripts/sx-browser.js

@@ -31,7 +31,7 @@
   // =========================================================================
 
   var NIL = Object.freeze({ _nil: true, toString: function() { return "nil"; } });
-  var SX_VERSION = "2026-04-26T18:15:33Z";
+  var SX_VERSION = "2026-04-26T19:02:22Z";
 
   function isNil(x) { return x === NIL || x === null || x === undefined; }
   function isSxTruthy(x) { return x !== false && !isNil(x); }
@@ -697,6 +697,26 @@
   };
 
 
+  // stdlib.bitwise
+  PRIMITIVES["bitwise-and"] = function(a, b) { return (a & b) | 0; };
+  PRIMITIVES["bitwise-or"]  = function(a, b) { return (a | b) | 0; };
+  PRIMITIVES["bitwise-xor"] = function(a, b) { return (a ^ b) | 0; };
+  PRIMITIVES["bitwise-not"] = function(a)    { return ~a; };
+  PRIMITIVES["arithmetic-shift"] = function(a, count) {
+    return count >= 0 ? (a << count) | 0 : a >> (-count);
+  };
+  PRIMITIVES["bit-count"] = function(a) {
+    var n = Math.abs(a) >>> 0;
+    n = n - ((n >> 1) & 0x55555555);
+    n = (n & 0x33333333) + ((n >> 2) & 0x33333333);
+    return (((n + (n >> 4)) & 0x0f0f0f0f) * 0x01010101) >>> 24;
+  };
+  PRIMITIVES["integer-length"] = function(a) {
+    if (a === 0) return 0;
+    return 32 - Math.clz32(Math.abs(a));
+  };
+
+
   function isPrimitive(name) { return name in PRIMITIVES; }
   function getPrimitive(name) { return PRIMITIVES[name]; }
 

spec/primitives.sx

@@ -805,3 +805,47 @@
   :doc "Create a new empty mutable string buffer for O(1) amortised append.")
 
 (define-module :stdlib.coroutines)
+
+(define-module :stdlib.bitwise)
+
+(define-primitive
+  "bitwise-and"
+  :params (((a :as number) (b :as number)))
+  :returns "number"
+  :doc "Bitwise AND of two integers.")
+
+(define-primitive
+  "bitwise-or"
+  :params (((a :as number) (b :as number)))
+  :returns "number"
+  :doc "Bitwise OR of two integers.")
+
+(define-primitive
+  "bitwise-xor"
+  :params (((a :as number) (b :as number)))
+  :returns "number"
+  :doc "Bitwise XOR of two integers.")
+
+(define-primitive
+  "bitwise-not"
+  :params ((a :as number))
+  :returns "number"
+  :doc "Bitwise NOT (one's complement) of an integer.")
+
+(define-primitive
+  "arithmetic-shift"
+  :params (((a :as number) (count :as number)))
+  :returns "number"
+  :doc "Arithmetic shift: left if count > 0, right if count < 0.")
+
+(define-primitive
+  "bit-count"
+  :params ((a :as number))
+  :returns "number"
+  :doc "Count set bits (popcount) in a non-negative integer.")
+
+(define-primitive
+  "integer-length"
+  :params ((a :as number))
+  :returns "number"
+  :doc "Number of bits needed to represent integer a (excluding sign).")

spec/tests/test-bitwise.sx

@@ -0,0 +1,157 @@
+(defsuite
+  "bitwise-operations"
+  (deftest
+    "bitwise-and basic"
+    (do
+      (assert= 0 (bitwise-and 0 0))
+      (assert= 1 (bitwise-and 3 1))
+      (assert= 0 (bitwise-and 5 2))
+      (assert= 4 (bitwise-and 12 6))))
+  (deftest
+    "bitwise-and identity and zero"
+    (do
+      (assert= 255 (bitwise-and 255 255))
+      (assert= 0 (bitwise-and 255 0))))
+  (deftest
+    "bitwise-or basic"
+    (do
+      (assert= 0 (bitwise-or 0 0))
+      (assert= 3 (bitwise-or 1 2))
+      (assert= 7 (bitwise-or 5 3))
+      (assert= 15 (bitwise-or 9 6))))
+  (deftest
+    "bitwise-or identity"
+    (do
+      (assert= 255 (bitwise-or 255 0))
+      (assert= 255 (bitwise-or 0 255))))
+  (deftest
+    "bitwise-xor basic"
+    (do
+      (assert= 0 (bitwise-xor 0 0))
+      (assert= 3 (bitwise-xor 1 2))
+      (assert= 6 (bitwise-xor 3 5))
+      (assert= 0 (bitwise-xor 255 255))))
+  (deftest
+    "bitwise-xor toggle bits"
+    (do
+      (assert= 14 (bitwise-xor 10 4))
+      (assert= 10 (bitwise-xor 14 4))))
+  (deftest
+    "bitwise-not zero"
+    (do (assert= -1 (bitwise-not 0))))
+  (deftest
+    "bitwise-not positive"
+    (do
+      (assert= -2 (bitwise-not 1))
+      (assert= -5 (bitwise-not 4))
+      (assert= -256 (bitwise-not 255))))
+  (deftest
+    "bitwise-not negative"
+    (do
+      (assert= 0 (bitwise-not -1))
+      (assert= 1 (bitwise-not -2))
+      (assert= 4 (bitwise-not -5))))
+  (deftest
+    "bitwise-not double negation"
+    (do
+      (assert= 42 (bitwise-not (bitwise-not 42)))
+      (assert= 0 (bitwise-not (bitwise-not 0)))))
+  (deftest
+    "arithmetic-shift left"
+    (do
+      (assert= 2 (arithmetic-shift 1 1))
+      (assert= 4 (arithmetic-shift 1 2))
+      (assert= 16 (arithmetic-shift 1 4))
+      (assert= 8 (arithmetic-shift 2 2))))
+  (deftest
+    "arithmetic-shift right"
+    (do
+      (assert= 1 (arithmetic-shift 2 -1))
+      (assert= 1 (arithmetic-shift 4 -2))
+      (assert= 5 (arithmetic-shift 10 -1))
+      (assert= 2 (arithmetic-shift 16 -3))))
+  (deftest
+    "arithmetic-shift by zero"
+    (do
+      (assert= 42 (arithmetic-shift 42 0))
+      (assert= 0 (arithmetic-shift 0 5))))
+  (deftest
+    "arithmetic-shift negative value right preserves sign"
+    (do
+      (assert= -1 (arithmetic-shift -1 -1))
+      (assert= -2 (arithmetic-shift -4 -1))))
+  (deftest
+    "bit-count zero"
+    (do (assert= 0 (bit-count 0))))
+  (deftest
+    "bit-count powers of two"
+    (do
+      (assert= 1 (bit-count 1))
+      (assert= 1 (bit-count 2))
+      (assert= 1 (bit-count 4))
+      (assert= 1 (bit-count 128))))
+  (deftest
+    "bit-count all-ones values"
+    (do
+      (assert= 8 (bit-count 255))
+      (assert= 4 (bit-count 15))
+      (assert= 2 (bit-count 3))))
+  (deftest
+    "bit-count mixed"
+    (do
+      (assert= 3 (bit-count 7))
+      (assert= 2 (bit-count 5))
+      (assert= 3 (bit-count 11))
+      (assert= 4 (bit-count 30))))
+  (deftest
+    "integer-length zero"
+    (do (assert= 0 (integer-length 0))))
+  (deftest
+    "integer-length powers of two"
+    (do
+      (assert= 1 (integer-length 1))
+      (assert= 2 (integer-length 2))
+      (assert= 3 (integer-length 4))
+      (assert= 4 (integer-length 8))
+      (assert= 8 (integer-length 128))))
+  (deftest
+    "integer-length non-powers"
+    (do
+      (assert= 2 (integer-length 3))
+      (assert= 3 (integer-length 5))
+      (assert= 3 (integer-length 7))
+      (assert= 8 (integer-length 255))
+      (assert= 9 (integer-length 256))))
+  (deftest
+    "bitwise ops compose"
+    (do
+      (assert=
+        5
+        (bitwise-and
+          (bitwise-or 5 3)
+          (bitwise-xor 7 2)))
+      (assert= 0 (bitwise-and 170 85))))
+  (deftest
+    "arithmetic-shift round-trip"
+    (do
+      (assert=
+        10
+        (arithmetic-shift (arithmetic-shift 10 3) -3))))
+  (deftest
+    "extract bits with mask"
+    (do
+      (let
+        ((x 52))
+        (assert=
+          5
+          (bitwise-and (arithmetic-shift x -2) 7)))))
+  (deftest
+    "clear low bits with bitwise-not mask"
+    (do
+      (assert= 252 (bitwise-and 255 (bitwise-not 3)))))
+  (deftest
+    "integer-length after shift"
+    (do
+      (assert=
+        4
+        (integer-length (arithmetic-shift 1 3))))))