[interpreter] Create custom call opcodes for specific argument counts

src/interpreter/interpreter.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/interpreter.h"
 
+#include <array>
 #include <fstream>
 #include <memory>
 
 #include "src/ast/prettyprinter.h"
 #include "src/builtins/builtins-arguments.h"
 #include "src/builtins/builtins-constructor.h"
 #include "src/builtins/builtins-object.h"
 #include "src/code-factory.h"
 #include "src/compilation-info.h"
 #include "src/compiler.h"
@@ skipping 110 matching lines @@
 
   // Initialization should have been successful.
   DCHECK(IsDispatchTableInitialized());
 }
 
 void Interpreter::InstallBytecodeHandler(Zone* zone, Bytecode bytecode,
                                          OperandScale operand_scale,
                                          BytecodeGeneratorFunc generator) {
   if (!Bytecodes::BytecodeHasHandler(bytecode, operand_scale)) return;
 
-  InterpreterDispatchDescriptor descriptor(isolate_);
-  compiler::CodeAssemblerState state(
-      isolate_, zone, descriptor, Code::ComputeFlags(Code::BYTECODE_HANDLER),
-      Bytecodes::ToString(bytecode), Bytecodes::ReturnCount(bytecode));
-  InterpreterAssembler assembler(&state, bytecode, operand_scale);
-  if (Bytecodes::MakesCallAlongCriticalPath(bytecode)) {
-    assembler.SaveBytecodeOffset();
+  size_t index = GetDispatchTableIndex(bytecode, operand_scale);
+  switch (bytecode) {
+    case Bytecode::kCallProperty:
+    case Bytecode::kCallProperty0:
+    case Bytecode::kCallProperty1:
+    case Bytecode::kCallProperty2: {
+      const int offset = static_cast<int>(Bytecode::kCallProperty) -
+                         static_cast<int>(Bytecode::kCall);
+      STATIC_ASSERT(offset ==
+                    static_cast<int>(Bytecode::kCallProperty0) -
+                        static_cast<int>(Bytecode::kCall0));
+      STATIC_ASSERT(offset ==
+                    static_cast<int>(Bytecode::kCallProperty1) -
+                        static_cast<int>(Bytecode::kCall1));
+      STATIC_ASSERT(offset ==
+                    static_cast<int>(Bytecode::kCallProperty2) -
+                        static_cast<int>(Bytecode::kCall2));

[rmcilroy, 2017/02/17 11:37:19]

Can you also DCHECK that offset < index

[danno, 2017/02/17 17:18:43]

Done.

+      dispatch_table_[index] = dispatch_table_[index - offset];
+      break;
+    }

[rmcilroy, 2017/02/17 11:37:19]

Could we pull the duplication logic out to a separate helper function and run
the check at the top, e.g.:

if (!Bytecodes::BytecodeHasHandler(bytecode, operand_scale)) return;
if (ReuseExistingHandler(bytecode, operand_scale)) return;

where ReuseExistingHandler updates the dispatch table.

[danno, 2017/02/17 17:18:43]

Done.

+
+    default: {
+      InterpreterDispatchDescriptor descriptor(isolate_);
+      compiler::CodeAssemblerState state(
+          isolate_, zone, descriptor,
+          Code::ComputeFlags(Code::BYTECODE_HANDLER),
+          Bytecodes::ToString(bytecode), Bytecodes::ReturnCount(bytecode));
+      InterpreterAssembler assembler(&state, bytecode, operand_scale);
+      if (Bytecodes::MakesCallAlongCriticalPath(bytecode)) {
+        assembler.SaveBytecodeOffset();
+      }
+      (this->*generator)(&assembler);
+      Handle<Code> code = compiler::CodeAssembler::GenerateCode(&state);
+      dispatch_table_[index] = code->entry();
+      TraceCodegen(code);
+      PROFILE(isolate_,
+              CodeCreateEvent(
+                  CodeEventListener::BYTECODE_HANDLER_TAG,
+                  AbstractCode::cast(*code),
+                  Bytecodes::ToString(bytecode, operand_scale).c_str()));
+      break;
+    }
   }
-  (this->*generator)(&assembler);
-  Handle<Code> code = compiler::CodeAssembler::GenerateCode(&state);
-  size_t index = GetDispatchTableIndex(bytecode, operand_scale);
-  dispatch_table_[index] = code->entry();
-  TraceCodegen(code);
-  PROFILE(isolate_, CodeCreateEvent(
-                        CodeEventListener::BYTECODE_HANDLER_TAG,
-                        AbstractCode::cast(*code),
-                        Bytecodes::ToString(bytecode, operand_scale).c_str()));
 }
 
 Code* Interpreter::GetBytecodeHandler(Bytecode bytecode,
                                       OperandScale operand_scale) {
   DCHECK(IsDispatchTableInitialized());
   DCHECK(Bytecodes::BytecodeHasHandler(bytecode, operand_scale));
   size_t index = GetDispatchTableIndex(bytecode, operand_scale);
   Address code_entry = dispatch_table_[index];
   return Code::GetCodeFromTargetAddress(code_entry);
 }
@@ skipping 1980 matching lines @@
   Node* slot_id = __ BytecodeOperandIdx(3);
   Node* feedback_vector = __ LoadFeedbackVector();
   Node* context = __ GetContext();
   Node* result =
       __ CallJSWithFeedback(function, context, receiver_arg, args_count,
                             slot_id, feedback_vector, tail_call_mode);
   __ SetAccumulator(result);
   __ Dispatch();
 }
 
+void Interpreter::DoJSCallN(InterpreterAssembler* assembler, int n) {

[rmcilroy, 2017/02/17 11:37:19]

nit - n -> arg_count

[danno, 2017/02/17 17:18:43]

Done.

+  const int kFunctionOperandCount = 1;
+  const int kReceiverOperandCount = 1;
+  const int kBoilerplatParameterCount = 7;
+  const int kReceiveParameterOffset = 5;

[rmcilroy, 2017/02/17 11:37:19]

nit - receiverParameterOffset

[danno, 2017/02/17 17:18:43]

Done.

+
+  Node* function_reg = __ BytecodeOperandReg(0);
+  Node* function = __ LoadRegister(function_reg);
+  std::array<Node*, Bytecodes::kMaxOperands + kBoilerplatParameterCount> temp;
+  for (int i = 0; i < (n + kReceiverOperandCount); ++i) {

[rmcilroy, 2017/02/17 11:37:19]

nit - could you do these in-order (the for loop between temp[4] and temp[n+6], 

[danno, 2017/02/17 17:18:43]

Done.

+    Node* reg = __ BytecodeOperandReg(i + kFunctionOperandCount);

[rmcilroy, 2017/02/17 11:37:19]

nit - I find the use of kFunctionOperandCount and kReceiverOperandCount a bit
confusing. How about:
  kRecieverOperandIndex = 1;
  kRecieverCount = 1;
  kSlotOperandIndex = kRecieverOperandIndex + kRecieverOperandCount + n;  

[danno, 2017/02/17 17:18:43]

Done.

+    temp[i + kReceiveParameterOffset] = __ LoadRegister(reg);
+  }
+  Callable call_ic = CodeFactory::CallIC(isolate_);
+  temp[0] = __ HeapConstant(call_ic.code());
+  temp[1] = function;
+  temp[2] = __ Int32Constant(n);
+  temp[3] = __ BytecodeOperandIdxInt32(n + kFunctionOperandCount +
+                                       kReceiverOperandCount);
+  temp[4] = __ LoadFeedbackVector();
+  temp[n + 6] = __ GetContext();

[rmcilroy, 2017/02/17 11:37:19]

nit - temp[5 + kRecieverCount + n]

[danno, 2017/02/17 17:18:43]

Done.

+  Node* result = __ CallStubN(call_ic.descriptor(), 1,
+                              n + kBoilerplatParameterCount, &temp[0]);
+  __ SetAccumulator(result);
+  __ Dispatch();
+}
+
 // Call <callable> <receiver> <arg_count> <feedback_slot_id>
 //
 // Call a JSfunction or Callable in |callable| with the |receiver| and
 // |arg_count| arguments in subsequent registers. Collect type feedback
 // into |feedback_slot_id|
 void Interpreter::DoCall(InterpreterAssembler* assembler) {
   DoJSCall(assembler, TailCallMode::kDisallow);
 }
 
-// CallProperty <callable> <receiver> <arg_count> <feedback_slot_id>
-//
-// Call a JSfunction or Callable in |callable| with the |receiver| and
-// |arg_count| arguments in subsequent registers. Collect type feedback into
-// |feedback_slot_id|. The callable is known to be a property of the receiver.
+void Interpreter::DoCall0(InterpreterAssembler* assembler) {
+  DoJSCallN(assembler, 0);
+}
+
+void Interpreter::DoCall1(InterpreterAssembler* assembler) {
+  DoJSCallN(assembler, 1);
+}
+
+void Interpreter::DoCall2(InterpreterAssembler* assembler) {
+  DoJSCallN(assembler, 2);
+}
+
 void Interpreter::DoCallProperty(InterpreterAssembler* assembler) {
-  // TODO(leszeks): Look into making the interpreter use the fact that the
-  // receiver is non-null.
-  DoJSCall(assembler, TailCallMode::kDisallow);
+  // Same as Call
+  UNREACHABLE();
+}
+
+void Interpreter::DoCallProperty0(InterpreterAssembler* assembler) {
+  // Same as Call0
+  UNREACHABLE();
+}
+
+void Interpreter::DoCallProperty1(InterpreterAssembler* assembler) {
+  // Same as Call1
+  UNREACHABLE();
+}
+
+void Interpreter::DoCallProperty2(InterpreterAssembler* assembler) {
+  // Same as Call2
+  UNREACHABLE();
 }
 
 // TailCall <callable> <receiver> <arg_count> <feedback_slot_id>
 //
 // Tail call a JSfunction or Callable in |callable| with the |receiver| and
 // |arg_count| arguments in subsequent registers. Collect type feedback
 // into |feedback_slot_id|
 void Interpreter::DoTailCall(InterpreterAssembler* assembler) {
   DoJSCall(assembler, TailCallMode::kAllow);
 }
@@ skipping 39 matching lines @@
 // <first_return + 1>
 void Interpreter::DoCallRuntimeForPair(InterpreterAssembler* assembler) {
   // Call the runtime function.
   Node* function_id = __ BytecodeOperandRuntimeId(0);
   Node* first_arg_reg = __ BytecodeOperandReg(1);
   Node* first_arg = __ RegisterLocation(first_arg_reg);
   Node* args_count = __ BytecodeOperandCount(2);
   Node* context = __ GetContext();
   Node* result_pair =
       __ CallRuntimeN(function_id, context, first_arg, args_count, 2);
-
   // Store the results in <first_return> and <first_return + 1>
   Node* first_return_reg = __ BytecodeOperandReg(3);
   Node* second_return_reg = __ NextRegister(first_return_reg);
   Node* result0 = __ Projection(0, result_pair);
   Node* result1 = __ Projection(1, result_pair);
   __ StoreRegister(result0, first_return_reg);
   __ StoreRegister(result1, second_return_reg);
   __ Dispatch();
 }
 
@@ skipping 1126 matching lines @@
   __ StoreObjectField(generator, JSGeneratorObject::kContinuationOffset,
       __ SmiTag(new_state));
   __ SetAccumulator(old_state);
 
   __ Dispatch();
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8