null-aware operators in the VM

runtime/vm/ast.h

Index: runtime/vm/ast.h
diff --git a/runtime/vm/ast.h b/runtime/vm/ast.h
index 4848a3f69f11c03f00f50bb51f22ec30e10e6173..eef162a00e9efd38fe249caee00e50ca63f38bbd 100644
--- a/runtime/vm/ast.h
+++ b/runtime/vm/ast.h
@@ -1421,11 +1421,13 @@ class InstanceCallNode : public AstNode {
   InstanceCallNode(intptr_t token_pos,
                    AstNode* receiver,
                    const String& function_name,
-                   ArgumentListNode* arguments)
+                   ArgumentListNode* arguments,
+                   bool is_conditional = false)
       : AstNode(token_pos),
         receiver_(receiver),
         function_name_(function_name),
-        arguments_(arguments) {
+        arguments_(arguments),
+        is_conditional_(is_conditional) {
     ASSERT(receiver_ != NULL);
     ASSERT(function_name_.IsNotTemporaryScopedHandle());
     ASSERT(function_name_.IsSymbol());
@@ -1436,6 +1438,11 @@ class InstanceCallNode : public AstNode {
   const String& function_name() const { return function_name_; }
   ArgumentListNode* arguments() const { return arguments_; }
 
+  bool is_conditional() const { return is_conditional_; }
+  void set_is_conditional(bool value) {
+    is_conditional_ = value;
+  }
+
   virtual void VisitChildren(AstNodeVisitor* visitor) const {
     receiver()->Visit(visitor);
     arguments()->Visit(visitor);
@@ -1447,6 +1454,7 @@ class InstanceCallNode : public AstNode {
   AstNode* receiver_;
   const String& function_name_;
   ArgumentListNode* arguments_;
+  bool is_conditional_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(InstanceCallNode);
 };
@@ -1459,7 +1467,21 @@ class InstanceGetterNode : public AstNode {
                      const String& field_name)
       : AstNode(token_pos),
         receiver_(receiver),
-        field_name_(field_name) {
+        field_name_(field_name),
+        is_conditional_(false) {
+    ASSERT(receiver_ != NULL);
+    ASSERT(field_name_.IsNotTemporaryScopedHandle());
+    ASSERT(field_name_.IsSymbol());
+  }
+
+  InstanceGetterNode(intptr_t token_pos,
+                     AstNode* receiver,
+                     const String& field_name,
+                     bool is_conditional)

[srdjan, 2015/06/17 18:15:36]

use default value as in InstanceCall (consistency).

[hausner, 2015/06/17 22:24:57]

Done.

+      : AstNode(token_pos),
+        receiver_(receiver),
+        field_name_(field_name),
+        is_conditional_(is_conditional) {
     ASSERT(receiver_ != NULL);
     ASSERT(field_name_.IsNotTemporaryScopedHandle());
     ASSERT(field_name_.IsSymbol());
@@ -1468,6 +1490,11 @@ class InstanceGetterNode : public AstNode {
   AstNode* receiver() const { return receiver_; }
   const String& field_name() const { return field_name_; }
 
+  bool is_conditional() const { return is_conditional_; }
+  void set_is_conditional(bool value) {
+    is_conditional_ = value;
+  }
+
   virtual void VisitChildren(AstNodeVisitor* visitor) const {
     receiver()->Visit(visitor);
   }
@@ -1482,6 +1509,7 @@ class InstanceGetterNode : public AstNode {
  private:
   AstNode* receiver_;
   const String& field_name_;
+  bool is_conditional_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(InstanceGetterNode);
 };
@@ -1496,7 +1524,24 @@ class InstanceSetterNode : public AstNode {
       : AstNode(token_pos),
         receiver_(receiver),
         field_name_(field_name),
-        value_(value) {
+        value_(value),
+        is_conditional_(false) {
+    ASSERT(receiver_ != NULL);
+    ASSERT(value_ != NULL);
+    ASSERT(field_name_.IsZoneHandle());
+    ASSERT(field_name_.IsSymbol());
+  }
+
+  InstanceSetterNode(intptr_t token_pos,
+                     AstNode* receiver,
+                     const String& field_name,
+                     AstNode* value,
+                     bool is_conditional)
+      : AstNode(token_pos),
+      receiver_(receiver),
+      field_name_(field_name),
+      value_(value),
+      is_conditional_(is_conditional) {
     ASSERT(receiver_ != NULL);
     ASSERT(value_ != NULL);
     ASSERT(field_name_.IsZoneHandle());
@@ -1507,6 +1552,11 @@ class InstanceSetterNode : public AstNode {
   const String& field_name() const { return field_name_; }
   AstNode* value() const { return value_; }
 
+  bool is_conditional() const { return is_conditional_; }
+  void set_is_conditional(bool value) {
+    is_conditional_ = value;
+  }
+
   virtual void VisitChildren(AstNodeVisitor* visitor) const {
     receiver()->Visit(visitor);
     value()->Visit(visitor);
@@ -1518,6 +1568,7 @@ class InstanceSetterNode : public AstNode {
   AstNode* receiver_;
   const String& field_name_;
   AstNode* value_;
+  bool is_conditional_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(InstanceSetterNode);
 };