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

src/interpreter/bytecode-array-builder.cc

 // Copyright 2015 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/interpreter/bytecode-array-builder.h"
 #include "src/compiler.h"
 
 namespace v8 {
 namespace internal {
 namespace interpreter {
@@ skipping 1044 matching lines @@
   if (!exit_seen_in_block_) {
     LoadUndefined();
     SetReturnPosition(literal);
     Return();
   }
 }
 
 BytecodeArrayBuilder& BytecodeArrayBuilder::Call(Register callable,
                                                  Register receiver_args,
                                                  size_t receiver_args_count,
-                                                 int feedback_slot) {
+                                                 int feedback_slot,
+                                                 TailCallMode tail_call_mode) {
+  Bytecode bytecode = BytecodeForCall(tail_call_mode);
   if (FitsInReg8Operand(callable) && FitsInReg8Operand(receiver_args) &&
       FitsInIdx8Operand(receiver_args_count) &&
       FitsInIdx8Operand(feedback_slot)) {
-    Output(Bytecode::kCall, callable.ToRawOperand(),
-           receiver_args.ToRawOperand(),
+    Output(bytecode, callable.ToRawOperand(), receiver_args.ToRawOperand(),
            static_cast<uint8_t>(receiver_args_count),
            static_cast<uint8_t>(feedback_slot));
   } else if (FitsInReg16Operand(callable) &&
              FitsInReg16Operand(receiver_args) &&
              FitsInIdx16Operand(receiver_args_count) &&
              FitsInIdx16Operand(feedback_slot)) {
-    Output(Bytecode::kCallWide, callable.ToRawOperand(),
-           receiver_args.ToRawOperand(),
+    bytecode = BytecodeForWideOperands(bytecode);
+    Output(bytecode, callable.ToRawOperand(), receiver_args.ToRawOperand(),
            static_cast<uint16_t>(receiver_args_count),
            static_cast<uint16_t>(feedback_slot));
   } else {
     UNIMPLEMENTED();
   }
   return *this;
 }
 
 BytecodeArrayBuilder& BytecodeArrayBuilder::New(Register constructor,
                                                 Register first_arg,
@@ skipping 329 matching lines @@
     default:
       UNREACHABLE();
       return static_cast<Bytecode>(-1);
   }
 }
 
 
 // static
 Bytecode BytecodeArrayBuilder::BytecodeForWideOperands(Bytecode bytecode) {
   switch (bytecode) {
+    case Bytecode::kCall:
+      return Bytecode::kCallWide;
+    case Bytecode::kTailCall:
+      return Bytecode::kTailCallWide;
     case Bytecode::kLoadIC:
       return Bytecode::kLoadICWide;
     case Bytecode::kKeyedLoadIC:
       return Bytecode::kKeyedLoadICWide;
     case Bytecode::kStoreICSloppy:
       return Bytecode::kStoreICSloppyWide;
     case Bytecode::kStoreICStrict:
       return Bytecode::kStoreICStrictWide;
     case Bytecode::kKeyedStoreICSloppy:
       return Bytecode::kKeyedStoreICSloppyWide;
@@ skipping 119 matching lines @@
     case STRICT:
       return Bytecode::kDeletePropertyStrict;
     case STRONG:
       UNIMPLEMENTED();
     default:
       UNREACHABLE();
   }
   return static_cast<Bytecode>(-1);
 }
 
+// static
+Bytecode BytecodeArrayBuilder::BytecodeForCall(TailCallMode tail_call_mode) {
+  switch (tail_call_mode) {
+    case TailCallMode::kDisallow:
+      return Bytecode::kCall;
+    case TailCallMode::kAllow:
+      return Bytecode::kTailCall;
+    default:
+      UNREACHABLE();
+  }
+  return static_cast<Bytecode>(-1);
+}
 
 // static
 bool BytecodeArrayBuilder::FitsInIdx8Operand(int value) {
   return kMinUInt8 <= value && value <= kMaxUInt8;
 }
 
 
 // static
 bool BytecodeArrayBuilder::FitsInIdx8Operand(size_t value) {
   return value <= static_cast<size_t>(kMaxUInt8);
@@ skipping 35 matching lines @@
 }
 
 // static
 bool BytecodeArrayBuilder::FitsInReg16OperandUntranslated(Register value) {
   return value.is_short_operand();
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8