[es6] Fix tail Call nodes marking.

src/parsing/parser.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/parsing/parser.h"
 
 #include "src/api.h"
 #include "src/ast/ast.h"
 #include "src/ast/ast-expression-rewriter.h"
 #include "src/ast/ast-expression-visitor.h"
@@ skipping 2789 matching lines @@
       // temp === undefined
       Expression* is_undefined = factory()->NewCompareOperation(
           Token::EQ_STRICT, assign,
           factory()->NewUndefinedLiteral(RelocInfo::kNoPosition), pos);
 
       // is_undefined ? this : is_object_conditional
       return_value = factory()->NewConditional(
           is_undefined, ThisExpression(scope_, factory(), pos),
           is_object_conditional, pos);
     }
-
-    // ES6 14.6.1 Static Semantics: IsInTailPosition
-    if (FLAG_harmony_tailcalls && !is_sloppy(language_mode())) {
-      return_value->MarkTail();
-    }
   }
   ExpectSemicolon(CHECK_OK);
 
   if (is_generator()) {
     Expression* generator = factory()->NewVariableProxy(
         function_state_->generator_object_variable());
     Expression* yield = factory()->NewYield(
         generator, return_value, Yield::kFinal, loc.beg_pos);
     result = factory()->NewExpressionStatement(yield, loc.beg_pos);
   } else {
@@ skipping 1946 matching lines @@
 
     VariableProxy* fproxy = factory()->NewVariableProxy(fvar);
     result->Set(kFunctionNameAssignmentIndex,
                 factory()->NewExpressionStatement(
                     factory()->NewAssignment(Token::INIT, fproxy,
                                              factory()->NewThisFunction(pos),
                                              RelocInfo::kNoPosition),
                     RelocInfo::kNoPosition));
   }
 
+  // ES6 14.6.1 Static Semantics: IsInTailPosition
+  if (FLAG_harmony_tailcalls && !is_sloppy(language_mode())) {
+    for (int i = 0; i < body->length(); i++) {
+      Statement* stmt = body->at(i);
+      stmt->MarkTail();
+    }
+  }
   return result;
 }
 
 
 PreParser::PreParseResult Parser::ParseLazyFunctionBodyWithPreParser(
     SingletonLogger* logger, Scanner::BookmarkScope* bookmark) {
   // This function may be called on a background thread too; record only the
   // main thread preparse times.
   if (pre_parse_timer_ != NULL) {
     pre_parse_timer_->Start();
@@ skipping 1553 matching lines @@
 
   statements->Add(get_return, zone);
   statements->Add(check_return, zone);
   statements->Add(call_return, zone);
   statements->Add(validate_result, zone);
 }
 
 
 }  // namespace internal
 }  // namespace v8