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>

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))))))