[es6] [interpreter] Add tail calls support to Ignition.

src/interpreter/interpreter.cc

Index: src/interpreter/interpreter.cc
diff --git a/src/interpreter/interpreter.cc b/src/interpreter/interpreter.cc
index 3e69c84d18e9b9ca26bae1f67bd47185502fc87a..c18689b7a6bd670c941a376e0a18bd17d9a3458c 100644
--- a/src/interpreter/interpreter.cc
+++ b/src/interpreter/interpreter.cc
@@ -1019,8 +1019,8 @@ void Interpreter::DoDeletePropertySloppy(InterpreterAssembler* assembler) {
   DoDelete(Runtime::kDeleteProperty_Sloppy, assembler);
 }
 
-
-void Interpreter::DoJSCall(InterpreterAssembler* assembler) {
+void Interpreter::DoJSCall(InterpreterAssembler* assembler,
+                           TailCallMode tail_call_mode) {
   Node* function_reg = __ BytecodeOperandReg(0);
   Node* function = __ LoadRegister(function_reg);
   Node* receiver_reg = __ BytecodeOperandReg(1);
@@ -1030,7 +1030,8 @@ void Interpreter::DoJSCall(InterpreterAssembler* assembler) {
   Node* args_count = __ Int32Sub(receiver_args_count, receiver_count);
   Node* context = __ GetContext();
   // TODO(rmcilroy): Use the call type feedback slot to call via CallStub.
-  Node* result = __ CallJS(function, context, receiver_arg, args_count);
+  Node* result =
+      __ CallJS(function, context, receiver_arg, args_count, tail_call_mode);
   __ SetAccumulator(result);
   __ Dispatch();
 }
@@ -1041,7 +1042,7 @@ void Interpreter::DoJSCall(InterpreterAssembler* assembler) {
 // Call a JSfunction or Callable in |callable| with the |receiver| and
 // |arg_count| arguments in subsequent registers.
 void Interpreter::DoCall(InterpreterAssembler* assembler) {
-  DoJSCall(assembler);
+  DoJSCall(assembler, TailCallMode::kDisallow);
 }
 
 
@@ -1050,7 +1051,23 @@ void Interpreter::DoCall(InterpreterAssembler* assembler) {
 // Call a JSfunction or Callable in |callable| with the |receiver| and
 // |arg_count| arguments in subsequent registers.
 void Interpreter::DoCallWide(InterpreterAssembler* assembler) {
-  DoJSCall(assembler);
+  DoJSCall(assembler, TailCallMode::kDisallow);
+}
+
+// TailCall <callable> <receiver> <arg_count>
+//
+// Tail call a JSfunction or Callable in |callable| with the |receiver| and
+// |arg_count| arguments in subsequent registers.
+void Interpreter::DoTailCall(InterpreterAssembler* assembler) {
+  DoJSCall(assembler, TailCallMode::kAllow);
+}
+
+// TailCallWide <callable> <receiver> <arg_count>
+//
+// Tail call a JSfunction or Callable in |callable| with the |receiver| and
+// |arg_count| arguments in subsequent registers.
+void Interpreter::DoTailCallWide(InterpreterAssembler* assembler) {
+  DoJSCall(assembler, TailCallMode::kAllow);
 }
 
 void Interpreter::DoCallRuntimeCommon(InterpreterAssembler* assembler) {
@@ -1141,7 +1158,8 @@ void Interpreter::DoCallJSRuntimeCommon(InterpreterAssembler* assembler) {
   Node* function = __ LoadContextSlot(native_context, context_index);
 
   // Call the function.
-  Node* result = __ CallJS(function, context, first_arg, args_count);
+  Node* result = __ CallJS(function, context, first_arg, args_count,
+                           TailCallMode::kDisallow);
   __ SetAccumulator(result);
   __ Dispatch();
 }