Implement type argument access and reification of runtime types.

pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart

Index: pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
diff --git a/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart b/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
index e0adf01cd87078cdc1c2eadb4d497eee1266bfa0..7272c896c8ff365de5e08359a62d4e30cd8d4611 100644
--- a/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
+++ b/pkg/compiler/lib/src/tree_ir/tree_ir_nodes.dart
@@ -6,7 +6,7 @@ library tree_ir_nodes;
 
 import '../constants/expressions.dart';
 import '../constants/values.dart' as values;
-import '../dart_types.dart' show DartType, GenericType;
+import '../dart_types.dart' show DartType, GenericType, TypeVariableType;
 import '../elements/elements.dart';
 import '../io/source_information.dart' show SourceInformation;
 import '../universe/universe.dart';
@@ -258,7 +258,7 @@ class This extends Expression {
   accept1(ExpressionVisitor1 visitor, arg) => visitor.visitThis(this, arg);
 }
 
-class ReifyTypeVar extends Expression {
+class ReifyTypeVar extends Expression implements DartSpecificNode {
   TypeVariableElement typeVariable;
 
   ReifyTypeVar(this.typeVariable);
@@ -755,6 +755,35 @@ class SetField extends Statement implements JsSpecificNode {
   accept1(StatementVisitor1 visitor, arg) => visitor.visitSetField(this, arg);
 }
 
+class ReifyRuntimeType extends Expression implements JsSpecificNode {
+  Expression value;
+
+  ReifyRuntimeType(this.value);
+
+  accept(ExpressionVisitor visitor) {
+    return visitor.visitReifyRuntimeType(this);
+  }
+
+  accept1(ExpressionVisitor1 visitor, arg) {
+    return visitor.visitReifyRuntimeType(this, arg);
+  }
+}
+
+class ReadTypeVariable extends Expression implements JsSpecificNode {
+  final TypeVariableType variable;
+  Expression target;
+
+  ReadTypeVariable(this.variable, this.target);
+
+  accept(ExpressionVisitor visitor) {
+    return visitor.visitReadTypeVariable(this);
+  }
+
+  accept1(ExpressionVisitor1 visitor, arg) {
+    return visitor.visitReadTypeVariable(this, arg);
+  }
+}
+
 abstract class ExpressionVisitor<E> {
   E visitExpression(Expression e) => e.accept(this);
   E visitVariableUse(VariableUse node);
@@ -778,6 +807,8 @@ abstract class ExpressionVisitor<E> {
   E visitGetField(GetField node);
   E visitCreateBox(CreateBox node);
   E visitCreateInstance(CreateInstance node);
+  E visitReifyRuntimeType(ReifyRuntimeType node);
+  E visitReadTypeVariable(ReadTypeVariable node);
 }
 
 abstract class ExpressionVisitor1<E, A> {
@@ -803,6 +834,8 @@ abstract class ExpressionVisitor1<E, A> {
   E visitGetField(GetField node, A arg);
   E visitCreateBox(CreateBox node, A arg);
   E visitCreateInstance(CreateInstance node, A arg);
+  E visitReifyRuntimeType(ReifyRuntimeType reifyRuntimeType, A arg);
+  E visitReadTypeVariable(ReadTypeVariable readTypeVariable, A arg);
 }
 
 abstract class StatementVisitor<S> {
@@ -997,4 +1030,12 @@ class RecursiveVisitor extends Visitor {
   visitCreateInstance(CreateInstance node) {
     node.arguments.forEach(visitExpression);
   }
+
+  visitReifyRuntimeType(ReifyRuntimeType node) {
+    visitExpression(node.value);
+  }
+
+  visitReadTypeVariable(ReadTypeVariable node) {
+    visitExpression(node.target);
+  }
 }