Changeset 197296 in webkit for trunk/Source/JavaScriptCore/bytecompiler/NodesCodegen.cpp

Timestamp:

Feb 28, 2016, 11:14:26 AM (9 years ago)

Author:

[email protected]

Message:

[ES6] Arrow function syntax. Emit loading&putting this/super only if they are used in arrow function. ​https://bugs.webkit.org/show_bug.cgi?id=153981

Small improvements

File:

• trunk/Source/JavaScriptCore/bytecompiler/NodesCodegen.cpp (modified) (3 diffs)

trunk/Source/JavaScriptCore/bytecompiler/NodesCodegen.cpp

@@ -147 +147 @@
 RegisterID* ThisNode::emitBytecode(BytecodeGenerator& generator, RegisterID* dst)
 {
-    if (generator.constructorKind() == ConstructorKind::Derived && generator.needsToUpdateArrowFunctionContext())
+    if (generator.constructorKind() == ConstructorKind::Derived && generator.needsToUpdateArrowFunctionContext() && generator.isThisUsedInInnerArrowFunction())
         generator.emitLoadThisFromArrowFunctionLexicalEnvironment();
 
@@ -724 +724 @@
     //    }
     // }
-    if (generator.constructorKind() == ConstructorKind::Derived && generator.needsToUpdateArrowFunctionContext())
+    if (generator.constructorKind() == ConstructorKind::Derived && generator.needsToUpdateArrowFunctionContext() && generator.isThisUsedInInnerArrowFunction())
         generator.emitLoadThisFromArrowFunctionLexicalEnvironment();
 
@@ -3139 +3139 @@
         // If there is no return we must automatically insert one.
         if (!returnNode) {
-            if (generator.constructorKind() == ConstructorKind::Derived && generator.needsToUpdateArrowFunctionContext())
+            if (generator.constructorKind() == ConstructorKind::Derived && generator.needsToUpdateArrowFunctionContext() && generator.isThisUsedInInnerArrowFunction())
                 generator.emitLoadThisFromArrowFunctionLexicalEnvironment(); // Arrow function can invoke 'super' in constructor and before leave constructor we need load 'this' from lexical arrow function environment