ffi: validate fast 32-bit integer argument ranges

Add i32, int32, u32, and uint32 to Fast API integer validation so
optimized calls reject invalid values instead of allowing V8 to
coerce or truncate them.

Signed-off-by: Kamat, Trivikram <16024985+trivikr@users.noreply.github.com>
Assisted-by: openai:gpt-5.6-sol

Author: trivikr

lib/internal/ffi/fast-api.js

@@ -50,6 +50,10 @@ const fastIntegerTypeInfo = {
   int16: { kind: 'number', min: -32768, max: 32767, label: 'an int16' },
   u16: { kind: 'number', min: 0, max: 65535, label: 'a uint16' },
   uint16: { kind: 'number', min: 0, max: 65535, label: 'a uint16' },
+  i32: { kind: 'number', min: -2147483648, max: 2147483647, label: 'an int32' },
+  int32: { kind: 'number', min: -2147483648, max: 2147483647, label: 'an int32' },
+  u32: { kind: 'number', min: 0, max: 4294967295, label: 'a uint32' },
+  uint32: { kind: 'number', min: 0, max: 4294967295, label: 'a uint32' },
   i64: { kind: 'bigint', min: I64_MIN, max: I64_MAX, label: 'an int64' },
   int64: { kind: 'bigint', min: I64_MIN, max: I64_MAX, label: 'an int64' },
   u64: { kind: 'bigint', min: 0n, max: U64_MAX, label: 'a uint64' },

src/ffi/fast.cc

@@ -164,7 +164,8 @@ bool SignatureNeedsFastIntegerValidation(const FFIFunction& fn) {
   for (const std::string& name : fn.arg_type_names) {
     if (name == "bool" || name == "char" || name == "i8" || name == "int8" ||
         name == "u8" || name == "uint8" || name == "i16" || name == "int16" ||
-        name == "u16" || name == "uint16" || name == "i64" || name == "int64" ||
+        name == "u16" || name == "uint16" || name == "i32" || name == "int32" ||
+        name == "u32" || name == "uint32" || name == "i64" || name == "int64" ||
         name == "u64" || name == "uint64") {
       return true;
     }

test/ffi/test-ffi-fast-integer-validation.js

@@ -28,6 +28,10 @@ test('fast FFI validates integer argument ranges', () => {
 
     function callU16(value) { return functions.add_u16(value, 0); }
 
+    function callI32(value) { return functions.add_i32(value, 0); }
+
+    function callU32(value) { return functions.add_u32(value, 0); }
+
     function callI64(value) { return functions.add_i64(value, 0n); }
 
     function callU64(value) { return functions.add_u64(value, 0n); }
@@ -37,6 +41,8 @@ test('fast FFI validates integer argument ranges', () => {
       [callU8, 0],
       [callI16, 0],
       [callU16, 0],
+      [callI32, 0],
+      [callU32, 0],
       [callI64, 0n],
       [callU64, 0n],
     ]) {
@@ -48,6 +54,14 @@ test('fast FFI validates integer argument ranges', () => {
     assert.throws(() => callU8(256), expect);
     assert.throws(() => callI16(32768), expect);
     assert.throws(() => callU16(65536), expect);
+    assert.throws(() => callI32(2147483648), expect);
+    assert.throws(() => callI32(-2147483649), expect);
+    assert.throws(() => callI32(1.5), expect);
+    assert.throws(() => callI32('1'), expect);
+    assert.throws(() => callU32(4294967296), expect);
+    assert.throws(() => callU32(-1), expect);
+    assert.throws(() => callU32(1.5), expect);
+    assert.throws(() => callU32('1'), expect);
     assert.throws(() => callI64(2n ** 63n), expect);
     assert.throws(() => callU64(2n ** 64n), expect);
   } finally {