[Interpreter] Add support for calling runtime functions which return a pair.

src/compiler/interpreter-assembler.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/compiler/interpreter-assembler.h"
 
 #include <ostream>
 
 #include "src/code-factory.h"
 #include "src/compiler/graph.h"
@@ skipping 130 matching lines @@
 }
 
 
 Node* InterpreterAssembler::StoreRegister(Node* value, Node* reg_index) {
   return raw_assembler_->Store(
       MachineRepresentation::kTagged, RegisterFileRawPointer(),
       RegisterFrameOffset(reg_index), value, kNoWriteBarrier);
 }
 
 
+Node* InterpreterAssembler::NextRegister(Node* reg_index) {
+  // Register indexes are negative, so the next index is minus one.
+  return IntPtrAdd(reg_index, Int32Constant(-1));
+}
+
+
 Node* InterpreterAssembler::BytecodeOperand(int operand_index) {
   DCHECK_LT(operand_index, interpreter::Bytecodes::NumberOfOperands(bytecode_));
   DCHECK_EQ(interpreter::OperandSize::kByte,
             interpreter::Bytecodes::GetOperandSize(bytecode_, operand_index));
   return raw_assembler_->Load(
       MachineType::Uint8(), BytecodeArrayTaggedPointer(),
       IntPtrAdd(BytecodeOffset(),
                 Int32Constant(interpreter::Bytecodes::GetOperandOffset(
                     bytecode_, operand_index))));
 }
@@ skipping 386 matching lines @@
   args[0] = arg1;
   args[1] = arg2;
   args[2] = arg3;
   args[3] = arg4;
   args[4] = arg5;
   args[5] = GetContext();
   return CallIC(descriptor, target, args);
 }
 
 
-Node* InterpreterAssembler::CallRuntime(Node* function_id, Node* first_arg,
+Node* InterpreterAssembler::CallRuntime(CallDescriptor* descriptor,
+                                        Handle<Code> call_stub,
+                                        Node* function_id, Node* first_arg,
                                         Node* arg_count) {
-  Callable callable = CodeFactory::InterpreterCEntry(isolate());
-  CallDescriptor* descriptor = Linkage::GetStubCallDescriptor(
-      isolate(), zone(), callable.descriptor(), 0, CallDescriptor::kNoFlags);
-
-  Node* code_target = HeapConstant(callable.code());
+  Node* code_target = HeapConstant(call_stub);
 
   // Get the function entry from the function id.
   Node* function_table = raw_assembler_->ExternalConstant(
       ExternalReference::runtime_function_table_address(isolate()));
   Node* function_offset = raw_assembler_->Int32Mul(
       function_id, Int32Constant(sizeof(Runtime::Function)));
   Node* function = IntPtrAdd(function_table, function_offset);
   Node* function_entry =
       raw_assembler_->Load(MachineType::Pointer(), function,
                            Int32Constant(offsetof(Runtime::Function, entry)));
 
   Node** args = zone()->NewArray<Node*>(4);
   args[0] = arg_count;
   args[1] = first_arg;
   args[2] = function_entry;
   args[3] = GetContext();
 
   return CallN(descriptor, code_target, args);
 }
 
 
+Node* InterpreterAssembler::CallRuntime(Node* function_id, Node* first_arg,
+                                        Node* arg_count) {
+  Callable callable = CodeFactory::InterpreterCEntry(isolate());
+  CallDescriptor* descriptor = Linkage::GetStubCallDescriptor(
+      isolate(), zone(), callable.descriptor(), 0, CallDescriptor::kNoFlags);
+
+  return CallRuntime(descriptor, callable.code(), function_id, first_arg,
+                     arg_count);
+}
+
+
+Node* InterpreterAssembler::CallRuntimePair(Node* function_id, Node* first_arg,
+                                            Node* arg_count) {
+  Callable callable = CodeFactory::InterpreterCEntryPair(isolate());
+  CallDescriptor* descriptor = Linkage::GetStubCallDescriptor(
+      isolate(), zone(), callable.descriptor(), 0, CallDescriptor::kNoFlags,
+      Operator::kNoProperties, MachineType::AnyTagged(), 2);
+
+  return CallRuntime(descriptor, callable.code(), function_id, first_arg,
+                     arg_count);
+}
+
+
 Node* InterpreterAssembler::CallRuntime(Runtime::FunctionId function_id,
                                         Node* arg1) {
   CallPrologue();
   Node* return_val =
       raw_assembler_->CallRuntime1(function_id, arg1, GetContext());
   CallEpilogue();
   return return_val;
 }
 
 
@@ skipping 140 matching lines @@
   return raw_assembler_->call_descriptor();
 }
 
 
 Zone* InterpreterAssembler::zone() { return raw_assembler_->zone(); }
 
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8