[dart2wasm] JS interop: use dartify functions specific to types being converted

`dartifyRaw` converts based on the runtime type and it's slow. Use
dartify functions specific to the expected Dart types when converting JS
values to Dart.

Benchmarks before:

    WasmJSInterop.call.bool.0Args(RunTimeRaw): 0.023022675490940652 ns.
    WasmJSInterop.call.nullableBool.0Args(RunTimeRaw): 0.02189111747851003 ns.
    WasmJSInterop.call.num.0Args(RunTimeRaw): 0.028148974752406197 ns.
    WasmJSInterop.call.nullableNum.0Args(RunTimeRaw): 0.028181565023670287 ns.
    WasmJSInterop.call.double.0Args(RunTimeRaw): 0.022986874778290176 ns.
    WasmJSInterop.call.nullableDouble.0Args(RunTimeRaw): 0.02907384054925038 ns.
    WasmJSInterop.call.int.0Args(RunTimeRaw): 0.029822888283378746 ns.
    WasmJSInterop.call.nullableInt.0Args(RunTimeRaw): 0.029088963619688168 ns.
    WasmJSInterop.call.string.0Args(RunTimeRaw): 0.020517746991606835 ns.
    WasmJSInterop.call.nullableString.0Args(RunTimeRaw): 0.02004299314157027 ns.
    WasmJSInterop.call.JSArray.0Args(RunTimeRaw): 0.020724174653887113 ns.
    WasmJSInterop.call.nullableJSArray.0Args(RunTimeRaw): 0.020034212115113702 ns.
    WasmJSInterop.call.JSUint8Array.0Args(RunTimeRaw): 0.030711090544501003 ns.
    WasmJSInterop.call.nullableJSUint8Array.0Args(RunTimeRaw): 0.030679086538461537 ns.

Benchmarks after:

    WasmJSInterop.call.bool.0Args(RunTimeRaw): 0.019944312674022892 ns.
    WasmJSInterop.call.nullableBool.0Args(RunTimeRaw): 0.0206124732933157 ns.
    WasmJSInterop.call.num.0Args(RunTimeRaw): 0.024475179056557175 ns.
    WasmJSInterop.call.nullableNum.0Args(RunTimeRaw): 0.02481147236988503 ns.
    WasmJSInterop.call.double.0Args(RunTimeRaw): 0.01829122645842903 ns.
    WasmJSInterop.call.nullableDouble.0Args(RunTimeRaw): 0.024581756014165346 ns.
    WasmJSInterop.call.int.0Args(RunTimeRaw): 0.01788861473387381 ns.
    WasmJSInterop.call.nullableInt.0Args(RunTimeRaw): 0.02333933933933934 ns.
    WasmJSInterop.call.string.0Args(RunTimeRaw): 0.018238532110091743 ns.
    WasmJSInterop.call.nullableString.0Args(RunTimeRaw): 0.019454117647058823 ns.
    WasmJSInterop.call.JSArray.0Args(RunTimeRaw): 0.020055434567412395 ns.
    WasmJSInterop.call.nullableJSArray.0Args(RunTimeRaw): 0.019759825327510916 ns.
    WasmJSInterop.call.JSUint8Array.0Args(RunTimeRaw): 0.030023959269242288 ns.
    WasmJSInterop.call.nullableJSUint8Array.0Args(RunTimeRaw): 0.03057233704292528 ns.

JSValue wrapper type performance (`JSUint8Array`, `JSArray`) does not
change as we had a special case (before this CL) for those types and
directly boxed them.

Issue: #60357
Change-Id: I0ee8e49cf3ed801634e4c6e13b1c597b2e730d59
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/424021
Commit-Queue: Ömer Ağacan <[email protected]>
Reviewed-by: Martin Kustermann <[email protected]>

Author: osa1

pkg/dart2wasm/lib/js/util.dart

@@ -35,6 +35,8 @@ class CoreTypesUtil {
   final Member wasmExternRefNullRef;
   final Class wasmI32Class;
   final Procedure wasmI32ToIntSigned;
+  final Procedure isDartNullTarget;
+  final Procedure throwArgumentNullErrorTarget;
 
   // Dart value to JS converters.
   final Procedure toJSBoolean;
@@ -94,7 +96,7 @@ class CoreTypesUtil {
 
   // NB. We rely on iteration ordering being insertion order to handle subtypes
   // before supertypes to convert as `int` and `double` before `num`.
-  late final Map<Class, Procedure> _externRefConverterMap = {
+  late final Map<Class, Procedure> _jsifyMap = {
     coreTypes.boolClass: toJSBoolean,
     coreTypes.intClass: jsifyInt,
     coreTypes.doubleClass: toJSNumber,
@@ -127,6 +129,44 @@ class CoreTypesUtil {
     coreTypes.functionClass: jsifyFunction,
   };
 
+  late final Map<Class, Procedure> _dartifyMap = {
+    coreTypes.boolClass:
+        coreTypes.index.getTopLevelProcedure('dart:_js_helper', 'toDartBool'),
+    coreTypes.intClass:
+        coreTypes.index.getTopLevelProcedure('dart:_js_helper', 'dartifyInt'),
+    coreTypes.doubleClass:
+        coreTypes.index.getTopLevelProcedure('dart:_js_helper', 'toDartNumber'),
+    coreTypes.numClass:
+        coreTypes.index.getTopLevelProcedure('dart:_js_helper', 'toDartNumber'),
+    coreTypes.stringClass:
+        coreTypes.index.getProcedure('dart:_string', 'JSStringImpl', 'fromRef'),
+    coreTypes.listClass:
+        coreTypes.index.getTopLevelProcedure('dart:_js_helper', 'toDartList'),
+    coreTypes.index.getClass('dart:typed_data', 'Int8List'): coreTypes.index
+        .getProcedure('dart:_js_types', 'JSInt8ArrayImpl', 'fromRef'),
+    coreTypes.index.getClass('dart:typed_data', 'Uint8List'): coreTypes.index
+        .getProcedure('dart:_js_types', 'JSUint8ArrayImpl', 'fromRef'),
+    coreTypes.index.getClass('dart:typed_data', 'Uint8ClampedList'): coreTypes
+        .index
+        .getProcedure('dart:_js_types', 'JSUint8ClampedArrayImpl', 'fromRef'),
+    coreTypes.index.getClass('dart:typed_data', 'Int16List'): coreTypes.index
+        .getProcedure('dart:_js_types', 'JSInt16ArrayImpl', 'fromRef'),
+    coreTypes.index.getClass('dart:typed_data', 'Uint16List'): coreTypes.index
+        .getProcedure('dart:_js_types', 'JSUint16ArrayImpl', 'fromRef'),
+    coreTypes.index.getClass('dart:typed_data', 'Int32List'): coreTypes.index
+        .getProcedure('dart:_js_types', 'JSInt32ArrayImpl', 'fromRef'),
+    coreTypes.index.getClass('dart:typed_data', 'Uint32List'): coreTypes.index
+        .getProcedure('dart:_js_types', 'JSUint32ArrayImpl', 'fromRef'),
+    coreTypes.index.getClass('dart:typed_data', 'Float32List'): coreTypes.index
+        .getProcedure('dart:_js_types', 'JSFloat32ArrayImpl', 'fromRef'),
+    coreTypes.index.getClass('dart:typed_data', 'Float64List'): coreTypes.index
+        .getProcedure('dart:_js_types', 'JSFloat64ArrayImpl', 'fromRef'),
+    coreTypes.index.getClass('dart:typed_data', 'ByteBuffer'): coreTypes.index
+        .getProcedure('dart:_js_types', 'JSArrayBufferImpl', 'fromRef'),
+    coreTypes.index.getClass('dart:typed_data', 'ByteData'): coreTypes.index
+        .getProcedure('dart:_js_types', 'JSDataViewImpl', 'fromRef'),
+  };
+
   CoreTypesUtil(this.coreTypes, this.extensionIndex)
       : allowInteropTarget = coreTypes.index
             .getTopLevelProcedure('dart:js_util', 'allowInterop'),
@@ -272,7 +312,11 @@ class CoreTypesUtil {
         byteBufferClass =
             coreTypes.index.getClass('dart:typed_data', 'ByteBuffer'),
         jsArrayBufferImplClass =
-            coreTypes.index.getClass('dart:_js_types', 'JSArrayBufferImpl');
+            coreTypes.index.getClass('dart:_js_types', 'JSArrayBufferImpl'),
+        isDartNullTarget = coreTypes.index
+            .getTopLevelProcedure('dart:_js_helper', 'isDartNull'),
+        throwArgumentNullErrorTarget = coreTypes.index.getTopLevelProcedure(
+            'dart:_error_utils', '_throwArgumentNullError');
 
   DartType get nonNullableObjectType =>
       coreTypes.objectRawType(Nullability.nonNullable);
@@ -322,11 +366,11 @@ class CoreTypesUtil {
         functionType: greaterThanOrEqualToTarget.getterType as FunctionType,
       );
 
-  /// Cast the [invocation] if needed to conform to the expected [returnType].
+  /// Cast the [invocation] if needed to conform to the expected [expectedType].
   Expression castInvocationForReturn(
-      Expression invocation, DartType returnType) {
+      Expression invocation, DartType expectedType) {
     Expression expression;
-    if (returnType is VoidType) {
+    if (expectedType is VoidType) {
       // Technically a `void` return value can still be used, by casting the
       // return type to `dynamic` or `Object?`. However this case should be
       // extremely rare, and `dartifyRaw` overhead for return values that should
@@ -336,27 +380,42 @@ class CoreTypesUtil {
           Block([ExpressionStatement(invocation)]), NullLiteral());
     }
 
-    if (isJSValueType(returnType)) {
+    if (isJSValueType(expectedType)) {
       // TODO(joshualitt): Expose boxed `JSNull` and `JSUndefined` to Dart
       // code after migrating existing users of js interop on Dart2Wasm.
       // expression = _createJSValue(invocation);
       // Casts are expensive, so we stick to a null-assertion if needed. If
       // the nullability can't be determined, cast.
       expression = invokeOneArg(jsValueBoxTarget, invocation);
-      final nullability = returnType.extensionTypeErasure.nullability;
+      final nullability = expectedType.extensionTypeErasure.nullability;
       if (nullability == Nullability.nonNullable) {
         expression = NullCheck(expression);
       } else if (nullability == Nullability.undetermined) {
-        expression = AsExpression(expression, returnType);
+        expression = AsExpression(expression, expectedType);
       }
     } else {
-      // Because we simply don't have enough information, we leave all JS
-      // numbers as doubles. However, in cases where we know the user expects
-      // an `int` we check that the double is an integer, and then insert a
-      // cast. We also let static interop types flow through without
-      // conversion, both as arguments, and as the return type.
-      expression = convertAndCast(
-          returnType, invokeOneArg(dartifyRawTarget, invocation));
+      final expectedTypeExtensionTypeErasure =
+          expectedType.extensionTypeErasure;
+      final expectNullable =
+          expectedTypeExtensionTypeErasure.isPotentiallyNullable;
+      final conversionProcedure =
+          _dartConversionProcedure(expectedTypeExtensionTypeErasure);
+      final invocationValueVar = VariableDeclaration('#jsInvocation',
+          initializer: invocation,
+          type: nullableWasmExternRefType,
+          isSynthesized: true);
+      expression = Let(
+        invocationValueVar,
+        ConditionalExpression(
+          StaticInvocation(
+              isDartNullTarget, Arguments([VariableGet(invocationValueVar)])),
+          expectNullable
+              ? NullLiteral()
+              : StaticInvocation(throwArgumentNullErrorTarget, Arguments([])),
+          invokeOneArg(conversionProcedure, VariableGet(invocationValueVar)),
+          expectedType,
+        ),
+      );
     }
     return expression;
   }
@@ -419,7 +478,7 @@ class CoreTypesUtil {
   /// non-nullable. This function does not check the nullability of [valueType]
   /// and assume that the argument passed to the conversion function won't be
   /// `null`.
-  Procedure? _conversionProcedure(
+  Procedure? _jsConversionProcedure(
       DartType valueType, DartType expectedType, TypeEnvironment typeEnv) {
     if (expectedType == coreTypes.doubleNonNullableRawType) {
       assert(valueType is InterfaceType &&
@@ -430,7 +489,7 @@ class CoreTypesUtil {
     assert(expectedType == nullableWasmExternRefType,
         'Unexpected expected type: $expectedType');
 
-    for (final entry in _externRefConverterMap.entries) {
+    for (final entry in _jsifyMap.entries) {
       if (typeEnv.isSubtypeOf(
           valueType,
           InterfaceType(entry.key, Nullability.nonNullable),
@@ -442,6 +501,21 @@ class CoreTypesUtil {
     // `dynamic` or `Object?`, convert based on runtime type.
     return jsifyRawTarget;
   }
+
+  /// Return the function to convert a value returned by an interop procedure
+  /// generated by [_Specializer.getRawInteropProcedure] to the expected Dart
+  /// type.
+  ///
+  /// The value passed to the returned conversion function should be an
+  /// `externref` and should be tested for `null` and `undefined`. The returned
+  /// procedures do not handle `null`s and `undefined`s.
+  Procedure _dartConversionProcedure(DartType expectedType) {
+    Procedure? conversionProcedure;
+    if (expectedType is InterfaceType) {
+      conversionProcedure = _dartifyMap[expectedType.classNode];
+    }
+    return conversionProcedure ?? dartifyRawTarget;
+  }
 }
 
 StaticInvocation invokeOneArg(Procedure target, Expression arg) =>
@@ -467,7 +541,7 @@ Expression jsifyValue(VariableDeclaration variable, DartType expectedType,
     conversionProcedure = coreTypes.jsValueUnboxTarget;
   } else {
     conversionProcedure =
-        coreTypes._conversionProcedure(variable.type, expectedType, typeEnv);
+        coreTypes._jsConversionProcedure(variable.type, expectedType, typeEnv);
   }
 
   final conversion = conversionProcedure == null

pkg/dart2wasm/lib/target.dart

@@ -169,6 +169,7 @@ class WasmTarget extends Target {
         'dart:_boxed_double',
         'dart:_boxed_int',
         'dart:_compact_hash',
+        'dart:_error_utils',
         'dart:_js_helper',
         'dart:_js_types',
         'dart:_list',

sdk/lib/_internal/wasm/lib/error_utils.dart

@@ -161,6 +161,13 @@ Never _throwNegativeOrZeroError(int value, [String? name]) {
   throw RangeError.range(value, 1, null, name);
 }
 
+@pragma("wasm:never-inline")
+@pragma("wasm:entry-point")
+Never _throwArgumentNullError() {
+  if (minify) throw _nullErrorWithoutDetails;
+  throw ArgumentError.notNull();
+}
+
 const _indexErrorWithoutDetails = _ErrorWithoutDetails(
   'IndexError (details omitted due to --minify)',
 );
@@ -176,6 +183,9 @@ const _negativeValueErrorWithoutDetails = _ErrorWithoutDetails(
 const _negativeOrZeroValueErrorWithoutDetails = _ErrorWithoutDetails(
   'Value was negative or zero (details omitted due to --minify)',
 );
+const _nullErrorWithoutDetails = _ErrorWithoutDetails(
+  'Value must not be null (details omitted due to --minify)',
+);
 
 class _ErrorWithoutDetails implements Error {
   final String _message;

sdk/lib/_internal/wasm/lib/js_helper.dart

@@ -92,6 +92,7 @@ extension JSAnyToExternRef on JSAny? {
 
 // For `dartify` and `jsify`, we match the conflation of `JSUndefined`, `JSNull`
 // and `null`.
+@pragma('wasm:entry-point')
 bool isDartNull(WasmExternRef? ref) => ref.isNull || isJSUndefined(ref);
 
 class JSArrayIteratorAdapter<T> implements Iterator<T> {
@@ -165,6 +166,7 @@ double toDartNumber(WasmExternRef? o) => JS<double>("o => o", o);
 @pragma('wasm:entry-point')
 WasmExternRef? toJSNumber(double o) => JS<WasmExternRef?>("o => o", o);
 
+@pragma('wasm:entry-point')
 bool toDartBool(WasmExternRef? o) => JS<bool>("o => o", o);
 
 WasmExternRef? toJSBoolean(bool b) => JS<WasmExternRef?>("b => !!b", b);
@@ -529,6 +531,18 @@ Object? dartifyRaw(WasmExternRef? ref, [int? refType]) {
   };
 }
 
+@pragma('wasm:entry-pint')
+int dartifyInt(WasmExternRef? ref) {
+  final dartDouble = toDartNumber(ref);
+  if (dartDouble.isFinite) {
+    final dartInt = dartDouble.toInt();
+    if (dartInt.toDouble() == dartDouble) {
+      return dartInt;
+    }
+  }
+  throw ArgumentError('JS value is not integer');
+}
+
 List<double> jsFloatTypedArrayToDartFloatTypedData(
   WasmExternRef? ref,
   List<double> makeTypedData(int size),
@@ -603,6 +617,7 @@ JSArray<T> toJSArray<T extends JSAny?>(List<T> list) {
   return result;
 }
 
+@pragma('wasm:entry-point')
 List<Object?> toDartList(WasmExternRef? ref) => List<Object?>.generate(
   objectLength(ref),
   (int n) => dartifyRaw(objectReadIndex(ref, n)),