Build CFG for various JS() foreign methods

pkg/compiler/lib/src/ssa/builder_kernel.dart

 // Copyright (c) 2016, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 import 'package:kernel/ast.dart' as ir;
 
 import '../common.dart';
 import '../common/codegen.dart' show CodegenRegistry, CodegenWorkItem;
 import '../common/names.dart';
 import '../common/tasks.dart' show CompilerTask;
 import '../compiler.dart';
+import '../constants/values.dart' show StringConstantValue;
 import '../dart_types.dart';
 import '../elements/elements.dart';
 import '../io/source_information.dart';
+import '../js/js.dart' as js;
 import '../js_backend/backend.dart' show JavaScriptBackend;
 import '../kernel/kernel.dart';
+import '../native/native.dart' as native;
 import '../resolution/tree_elements.dart';
 import '../tree/dartstring.dart';
 import '../types/masks.dart';
 import '../universe/selector.dart';
+import '../universe/side_effects.dart' show SideEffects;
 import 'graph_builder.dart';
 import 'kernel_ast_adapter.dart';
 import 'kernel_string_builder.dart';
 import 'locals_handler.dart';
 import 'loop_handler.dart';
 import 'nodes.dart';
 import 'ssa_branch_builder.dart';
 
 class SsaKernelBuilderTask extends CompilerTask {
   final JavaScriptBackend backend;
@@ skipping 529 matching lines @@
   @override
   void visitMapEntry(ir.MapEntry mapEntry) {
     // Visit value before the key because each will push an expression to the
     // stack, so when we pop them off, the key is popped first, then the value.
     mapEntry.value.accept(this);
     mapEntry.key.accept(this);
   }
 
   @override
   void visitStaticGet(ir.StaticGet staticGet) {
-    var staticTarget = staticGet.target;
+    ir.Member staticTarget = staticGet.target;
     if (staticTarget is ir.Procedure &&
         staticTarget.kind == ir.ProcedureKind.Getter) {
       // Invoke the getter
       _pushStaticInvocation(staticTarget, const <HInstruction>[],
           astAdapter.returnTypeOf(staticTarget));
+    } else if (staticTarget is ir.Field && staticTarget.isConst) {
+      assert(staticTarget.initializer != null);
+      stack.add(graph.addConstant(
+          astAdapter.getConstantFor(staticTarget.initializer), compiler));
     } else {
       Element element = astAdapter.getElement(staticTarget).declaration;
       push(new HStatic(element, astAdapter.inferredTypeOf(staticTarget)));
     }
   }
 
   @override
   void visitStaticSet(ir.StaticSet staticSet) {
     staticSet.value.accept(this);
     HInstruction value = pop();
@@ skipping 78 matching lines @@
       argument.value.accept(this);
       result.add(pop());
     }
 
     return result;
   }
 
   @override
   void visitStaticInvocation(ir.StaticInvocation invocation) {
     ir.Procedure target = invocation.target;
+    if (astAdapter.isInForeignLibrary(target)) {
+      handleInvokeStaticForeign(invocation, target);
+      return;
+    }
     TypeMask typeMask = astAdapter.returnTypeOf(target);
 
     List<HInstruction> arguments = _visitArguments(invocation.arguments);
 
     _pushStaticInvocation(target, arguments, typeMask);
   }
 
+  void handleInvokeStaticForeign(
+      ir.StaticInvocation invocation, ir.Procedure target) {
+    String name = target.name.name;
+    if (name == 'JS') {
+      handleForeignJs(invocation);
+    } else if (name == 'JS_CURRENT_ISOLATE_CONTEXT') {
+      handleForeignJsCurrentIsolateContext(invocation);
+    } else if (name == 'JS_CALL_IN_ISOLATE') {
+      handleForeignJsCallInIsolate(invocation);
+    } else if (name == 'DART_CLOSURE_TO_JS') {
+      handleForeignDartClosureToJs(invocation, 'DART_CLOSURE_TO_JS');
+    } else if (name == 'RAW_DART_FUNCTION_REF') {
+      handleForeignRawFunctionRef(invocation, 'RAW_DART_FUNCTION_REF');
+    } else if (name == 'JS_SET_STATIC_STATE') {
+      handleForeignJsSetStaticState(invocation);
+    } else if (name == 'JS_GET_STATIC_STATE') {
+      handleForeignJsGetStaticState(invocation);
+    } else if (name == 'JS_GET_NAME') {
+      handleForeignJsGetName(invocation);
+    } else if (name == 'JS_EMBEDDED_GLOBAL') {
+      handleForeignJsEmbeddedGlobal(invocation);
+    } else if (name == 'JS_BUILTIN') {
+      handleForeignJsBuiltin(invocation);
+    } else if (name == 'JS_GET_FLAG') {
+      handleForeignJsGetFlag(invocation);
+    } else if (name == 'JS_EFFECT') {
+      stack.add(graph.addConstantNull(compiler));
+    } else if (name == 'JS_INTERCEPTOR_CONSTANT') {
+      handleJsInterceptorConstant(invocation);
+    } else if (name == 'JS_STRING_CONCAT') {
+      handleJsStringConcat(invocation);
+    } else {
+      compiler.reporter.internalError(
+          astAdapter.getNode(invocation), "Unknown foreign: ${name}");
+    }
+  }
+
+  bool _unexpectedForeignArguments(
+      ir.StaticInvocation invocation, String name, int minPositional,
+      [int maxPositional]) {
+    ir.Arguments arguments = invocation.arguments;
+    bool bad = false;
+    if (arguments.types.isNotEmpty) {
+      compiler.reporter.reportErrorMessage(
+          astAdapter.getNode(invocation),
+          MessageKind.GENERIC,
+          {'text': "Error: '$name' does not take type arguments."});
+      bad = true;
+    }
+    String pluralize(int count, String singular, String plural) {
+      if (count == 0) return 'no $plural';
+      if (count == 1) return 'one $singular';
+      if (count == 2) return 'two $plural';
+      return '$count ${plural}s';

[Harry Terkelsen, 2016/10/12 16:42:59]

should be '$count $plural'

[sra1, 2016/10/13 19:02:01]

Done.

+    }
+
+    if (arguments.positional.length < minPositional) {
+      String phrase = pluralize(minPositional, 'argument', 'arguments');
+      if (maxPositional != minPositional) phrase = 'at least $phrase';
+      compiler.reporter.reportErrorMessage(
+          astAdapter.getNode(invocation),
+          MessageKind.GENERIC,
+          {'text': "Error: Too few arguments. '$name' takes $phrase."});
+      bad = true;
+    }
+    if (maxPositional != null && arguments.positional.length > maxPositional) {
+      String phrase = pluralize(maxPositional, 'argument', 'arguments');
+      if (maxPositional != minPositional) phrase = 'at most $phrase';
+      compiler.reporter.reportErrorMessage(
+          astAdapter.getNode(invocation),
+          MessageKind.GENERIC,
+          {'text': "Error: Too many arguments. '$name' takes $phrase."});
+      bad = true;
+    }
+    if (arguments.named.isNotEmpty) {
+      compiler.reporter.reportErrorMessage(
+          astAdapter.getNode(invocation),
+          MessageKind.GENERIC,
+          {'text': "Error: '$name' does not take named arguments."});
+      bad = true;
+    }
+    return bad;
+  }
+
+  /// Returns the value of the string argument. The argument must evaluate to a
+  /// constant.  If there is an error, the error is reported and `null` is
+  /// returned.
+  String _foreignConstantStringArgument(
+      ir.StaticInvocation invocation, int position, String methodName,
+      [String adjective = '']) {
+    ir.Expression argument = invocation.arguments.positional[position];
+    argument.accept(this);
+    HInstruction instruction = pop();
+
+    if (!instruction.isConstantString()) {
+      compiler.reporter.reportErrorMessage(
+          astAdapter.getNode(argument), MessageKind.GENERIC, {
+        'text': "Error: Expected String constant as ${adjective}argument "
+            "to '$methodName'."
+      });
+      return null;
+    }
+
+    HConstant hConstant = instruction;
+    StringConstantValue stringConstant = hConstant.constant;
+    return stringConstant.primitiveValue.slowToString();
+  }
+
+  dynamic _foreignConstantEnumArgument(

[Harry Terkelsen, 2016/10/12 16:42:59]

this seems unused?

[sra1, 2016/10/13 19:02:01]

Removed

+      ir.StaticInvocation invocation, int position, String methodName,
+      [String adjective = '']) {
+    ir.Expression argument = invocation.arguments.positional[position];
+    argument.accept(this);
+    HInstruction instruction = pop();
+
+    if (!instruction.isConstant()) {
+      compiler.reporter.reportErrorMessage(
+          astAdapter.getNode(argument), MessageKind.GENERIC, {
+        'text': "Error: Expected String constant as ${adjective}argument "

[Harry Terkelsen, 2016/10/12 16:42:59]

should it be 'Expected enum constant ...'?

[sra1, 2016/10/13 19:02:01]

Acknowledged.

+            "to '$methodName'."
+      });
+      return null;
+    }
+
+    HConstant hConstant = instruction;
+    StringConstantValue stringConstant = hConstant.constant;

[Harry Terkelsen, 2016/10/12 16:42:59]

should this be an EnumConstantValue?

[sra1, 2016/10/13 19:02:01]

Acknowledged.

+    return stringConstant.primitiveValue.slowToString();
+  }
+
+  // TODO(sra): Remove when handleInvokeStaticForeign fully implemented.
+  void unhandledForeign(ir.StaticInvocation invocation) {
+    ir.Procedure target = invocation.target;
+    TypeMask typeMask = astAdapter.returnTypeOf(target);
+    List<HInstruction> arguments = _visitArguments(invocation.arguments);
+    _pushStaticInvocation(target, arguments, typeMask);
+  }
+
+  void handleForeignJsCurrentIsolateContext(ir.StaticInvocation invocation) {
+    unhandledForeign(invocation);
+  }
+
+  void handleForeignJsCallInIsolate(ir.StaticInvocation invocation) {
+    unhandledForeign(invocation);
+  }
+
+  void handleForeignDartClosureToJs(
+      ir.StaticInvocation invocation, String name) {
+    unhandledForeign(invocation);
+  }
+
+  void handleForeignRawFunctionRef(
+      ir.StaticInvocation invocation, String name) {
+    unhandledForeign(invocation);
+  }
+
+  void handleForeignJsSetStaticState(ir.StaticInvocation invocation) {
+    if (_unexpectedForeignArguments(invocation, 'JS_SET_STATIC_STATE', 0, 0)) {
+      stack.add(graph.addConstantNull(compiler)); // Result expected on stack.
+      return;
+    }
+    _visitArguments(invocation.arguments);
+    String isolateName = backend.namer.staticStateHolder;
+    SideEffects sideEffects = new SideEffects.empty();
+    sideEffects.setAllSideEffects();
+    push(new HForeignCode(js.js.parseForeignJS("$isolateName = #"),
+        backend.dynamicType, <HInstruction>[pop()],
+        nativeBehavior: native.NativeBehavior.CHANGES_OTHER,
+        effects: sideEffects));
+  }
+
+  void handleForeignJsGetStaticState(ir.StaticInvocation invocation) {
+    if (_unexpectedForeignArguments(invocation, 'JS_GET_STATIC_STATE', 0, 0)) {
+      stack.add(graph.addConstantNull(compiler)); // Result expected on stack.
+      return;
+    }
+
+    push(new HForeignCode(js.js.parseForeignJS(backend.namer.staticStateHolder),
+        backend.dynamicType, <HInstruction>[],
+        nativeBehavior: native.NativeBehavior.DEPENDS_OTHER));
+  }
+
+  void handleForeignJsGetName(ir.StaticInvocation invocation) {
+    if (_unexpectedForeignArguments(invocation, 'JS_GET_NAME', 1, 1)) {
+      stack.add(graph.addConstantNull(compiler)); // Result expected on stack.
+      return;
+    }
+
+    ir.Node argument = invocation.arguments.positional.first;
+    argument.accept(this);
+    HInstruction instruction = pop();
+
+    if (instruction is HConstant) {
+      js.Name name =
+          astAdapter.getNameForJsGetName(argument, instruction.constant);
+      stack.add(graph.addConstantStringFromName(name, compiler));
+      return;
+    }
+
+    compiler.reporter.reportErrorMessage(
+        astAdapter.getNode(argument),
+        MessageKind.GENERIC,
+        {'text': 'Error: Expected a JsGetName enum value.'});
+    stack.add(graph.addConstantNull(compiler)); // Result expected on stack.
+  }
+
+  void handleForeignJsEmbeddedGlobal(ir.StaticInvocation invocation) {
+    if (_unexpectedForeignArguments(invocation, 'JS_EMBEDDED_GLOBAL', 2, 2)) {
+      stack.add(graph.addConstantNull(compiler)); // Result expected on stack.
+      return;
+    }
+    String globalName = _foreignConstantStringArgument(
+        invocation, 1, 'JS_EMBEDDED_GLOBAL', 'second ');
+    js.Template expr = js.js.expressionTemplateYielding(
+        backend.emitter.generateEmbeddedGlobalAccess(globalName));
+
+    native.NativeBehavior nativeBehavior =
+        astAdapter.getNativeBehavior(invocation);
+    assert(invariant(astAdapter.getNode(invocation), nativeBehavior != null,
+        message: "No NativeBehavior for $invocation"));
+
+    TypeMask ssaType = astAdapter.typeFromNativeBehavior(nativeBehavior);
+    push(new HForeignCode(expr, ssaType, const <HInstruction>[],
+        nativeBehavior: nativeBehavior));
+  }
+
+  void handleForeignJsBuiltin(ir.StaticInvocation invocation) {
+    if (_unexpectedForeignArguments(invocation, 'JS_BUILTIN', 2)) {
+      stack.add(graph.addConstantNull(compiler)); // Result expected on stack.
+      return;
+    }
+
+    List<ir.Expression> arguments = invocation.arguments.positional;
+    ir.Expression nameArgument = arguments[1];
+
+    nameArgument.accept(this);
+    HInstruction instruction = pop();
+
+    js.Template template;
+    if (instruction is HConstant) {
+      template = astAdapter.getJsBuiltinTemplate(instruction.constant);
+    }
+    if (template == null) {
+      compiler.reporter.reportErrorMessage(
+          astAdapter.getNode(nameArgument),
+          MessageKind.GENERIC,
+          {'text': 'Error: Expected a JsBuiltin enum value.'});
+      stack.add(graph.addConstantNull(compiler)); // Result expected on stack.
+      return;
+    }
+
+    List<HInstruction> inputs = <HInstruction>[];
+    for (ir.Expression argument in arguments.skip(2)) {
+      argument.accept(this);
+      inputs.add(pop());
+    }
+
+    native.NativeBehavior nativeBehavior =
+        astAdapter.getNativeBehavior(invocation);
+    assert(invariant(astAdapter.getNode(invocation), nativeBehavior != null,
+        message: "No NativeBehavior for $invocation"));
+
+    TypeMask ssaType = astAdapter.typeFromNativeBehavior(nativeBehavior);
+    push(new HForeignCode(template, ssaType, inputs,
+        nativeBehavior: nativeBehavior));
+  }
+
+  void handleForeignJsGetFlag(ir.StaticInvocation invocation) {
+    if (_unexpectedForeignArguments(invocation, 'JS_GET_FLAG', 1, 1)) {
+      stack.add(
+          graph.addConstantBool(false, compiler)); // Result expected on stack.
+      return;
+    }
+    String name = _foreignConstantStringArgument(invocation, 0, 'JS_GET_FLAG');
+    bool value = false;
+    switch (name) {
+      case 'MUST_RETAIN_METADATA':
+        value = backend.mustRetainMetadata;
+        break;
+      case 'USE_CONTENT_SECURITY_POLICY':
+        value = compiler.options.useContentSecurityPolicy;
+        break;
+      default:
+        compiler.reporter.reportErrorMessage(
+            astAdapter.getNode(invocation),
+            MessageKind.GENERIC,
+            {'text': 'Error: Unknown internal flag "$name".'});
+    }
+    stack.add(graph.addConstantBool(value, compiler));
+  }
+
+  void handleJsInterceptorConstant(ir.StaticInvocation invocation) {
+    unhandledForeign(invocation);
+  }
+
+  void handleForeignJs(ir.StaticInvocation invocation) {
+    if (_unexpectedForeignArguments(invocation, 'JS', 2)) {
+      stack.add(graph.addConstantNull(compiler)); // Result expected on stack.
+      return;
+    }
+
+    native.NativeBehavior nativeBehavior =
+        astAdapter.getNativeBehavior(invocation);
+    assert(nativeBehavior != null);

[Harry Terkelsen, 2016/10/12 16:42:59]

remove this assert since it makes the next one unreachable

[sra1, 2016/10/13 19:02:01]

Done.

+    assert(invariant(astAdapter.getNode(invocation), nativeBehavior != null,
+        message: "No NativeBehavior for $invocation"));
+
+    List<HInstruction> inputs = <HInstruction>[];
+    for (ir.Expression argument in invocation.arguments.positional.skip(2)) {
+      argument.accept(this);
+      inputs.add(pop());
+    }
+
+    if (nativeBehavior.codeTemplate.positionalArgumentCount != inputs.length) {
+      compiler.reporter.reportErrorMessage(
+          astAdapter.getNode(invocation), MessageKind.GENERIC, {
+        'text': 'Mismatch between number of placeholders'
+            ' and number of arguments.'
+      });
+      stack.add(graph.addConstantNull(compiler)); // Result expected on stack.
+      return;
+    }
+
+    if (native.HasCapturedPlaceholders.check(nativeBehavior.codeTemplate.ast)) {
+      compiler.reporter.reportErrorMessage(
+          astAdapter.getNode(invocation), MessageKind.JS_PLACEHOLDER_CAPTURE);
+    }
+
+    TypeMask ssaType = astAdapter.typeFromNativeBehavior(nativeBehavior);
+
+    SourceInformation sourceInformation = null;
+    if (nativeBehavior.codeTemplate.isExpression) {

[Harry Terkelsen, 2016/10/12 16:42:58]

maybe rewrite this entire if statement as:

push(new HForeignCode(nativeBehavior.codeTemplate, ssaType, inputs,
           isStatement: !nativeBehavior.codeTemplate.isExpression,
           effects: nativeBehavior.sideEffects,
           nativeBehavior: nativeBehavior)
         ..sourceInformation = sourceInformation);

[sra1, 2016/10/13 19:02:01]

Done.

+      push(new HForeignCode(nativeBehavior.codeTemplate, ssaType, inputs,
+          effects: nativeBehavior.sideEffects, nativeBehavior: nativeBehavior)
+        ..sourceInformation = sourceInformation);
+    } else {
+      push(new HForeignCode(nativeBehavior.codeTemplate, ssaType, inputs,
+          isStatement: true,
+          effects: nativeBehavior.sideEffects,
+          nativeBehavior: nativeBehavior)
+        ..sourceInformation = sourceInformation);
+    }
+  }
+
+  void handleJsStringConcat(ir.StaticInvocation invocation) {
+    if (_unexpectedForeignArguments(invocation, 'JS_STRING_CONCAT', 2)) {
+      stack.add(graph.addConstantNull(compiler)); // Result expected on stack.
+      return;
+    }
+    List<HInstruction> inputs = _visitArguments(invocation.arguments);
+    assert(inputs.length == 2);
+    push(new HStringConcat(inputs[0], inputs[1], backend.stringType));
+  }
+
   void _pushStaticInvocation(
       ir.Node target, List<HInstruction> arguments, TypeMask typeMask) {
     HInstruction instruction = new HInvokeStatic(
         astAdapter.getElement(target).declaration, arguments, typeMask,
         targetCanThrow: astAdapter.getCanThrow(target));
     instruction.sideEffects = astAdapter.getSideEffects(target);
 
     push(instruction);
   }
 
@@ skipping 126 matching lines @@
     push(new HNot(popBoolified(), backend.boolType));
   }
 
   @override
   void visitStringConcatenation(ir.StringConcatenation stringConcat) {
     KernelStringBuilder stringBuilder = new KernelStringBuilder(this);
     stringConcat.accept(stringBuilder);
     stack.add(stringBuilder.result);
   }
 }