[es6] Introduce %ToInteger and %ToLength.

src/full-codegen/x64/full-codegen-x64.cc

Index: src/full-codegen/x64/full-codegen-x64.cc
diff --git a/src/full-codegen/x64/full-codegen-x64.cc b/src/full-codegen/x64/full-codegen-x64.cc
index 553e6270386cc003873f54530d11794e2def1587..7662dca268abb9addd8be8d0635341ed3b082c9a 100644
--- a/src/full-codegen/x64/full-codegen-x64.cc
+++ b/src/full-codegen/x64/full-codegen-x64.cc
@@ -3661,6 +3661,23 @@ void FullCodeGenerator::EmitSetValueOf(CallRuntime* expr) {
 }
 
 
+void FullCodeGenerator::EmitToInteger(CallRuntime* expr) {
+  ZoneList<Expression*>* args = expr->arguments();
+  DCHECK_EQ(1, args->length());
+
+  // Load the argument into rax and convert it.
+  VisitForAccumulatorValue(args->at(0));
+
+  // Convert the object to an integer.
+  Label done_convert;
+  __ JumpIfSmi(rax, &done_convert, Label::kNear);
+  __ Push(rax);
+  __ CallRuntime(Runtime::kToInteger, 1);
+  __ bind(&done_convert);
+  context()->Plug(rax);
+}
+
+
 void FullCodeGenerator::EmitNumberToString(CallRuntime* expr) {
   ZoneList<Expression*>* args = expr->arguments();
   DCHECK_EQ(args->length(), 1);