[Interpreter] generate-bytecode-expectations improvements.

test/cctest/interpreter/bytecode-expectations-printer.cc

 // Copyright 2016 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 "test/cctest/interpreter/bytecode-expectations-printer.h"
 
 #include <iostream>
 
 #include "include/libplatform/libplatform.h"
 #include "include/v8.h"
@@ skipping 20 matching lines @@
 std::string BytecodeExpectationsPrinter::WrapCodeInFunction(
     const char* function_name, const std::string& function_body) const {
   std::ostringstream program_stream;
   program_stream << "function " << function_name << "() {" << function_body
                  << "}\n"
                  << function_name << "();";
 
   return program_stream.str();
 }
 
-v8::Local<v8::Value> BytecodeExpectationsPrinter::CompileAndRun(
+v8::Local<v8::Script> BytecodeExpectationsPrinter::Compile(
     const char* program) const {
   v8::Local<v8::String> source = V8StringFromUTF8(program);
-  v8::Local<v8::Script> script =
-      v8::Script::Compile(isolate_->GetCurrentContext(), source)
-          .ToLocalChecked();
+  return v8::Script::Compile(isolate_->GetCurrentContext(), source)
+      .ToLocalChecked();
+}
 
+v8::Local<v8::Value> BytecodeExpectationsPrinter::Run(
+    v8::Local<v8::Script> script) const {
   v8::Local<v8::Value> result;
   CHECK(script->Run(isolate_->GetCurrentContext()).ToLocal(&result));
-
   return result;

[rmcilroy, 2016/02/16 16:43:48]

Not using the result? If not, just drop the return value.

[Stefano Sanfilippo, 2016/02/16 20:28:26]

Done.

 }
 
 i::Handle<v8::internal::BytecodeArray>
 BytecodeExpectationsPrinter::GetBytecodeArrayForGlobal(
     const char* global_name) const {
   const v8::Local<v8::Context>& context = isolate_->GetCurrentContext();
   v8::Local<v8::String> v8_global_name = V8StringFromUTF8(global_name);
   v8::Local<v8::Function> function = v8::Local<v8::Function>::Cast(
       context->Global()->Get(context, v8_global_name).ToLocalChecked());
   i::Handle<i::JSFunction> js_function =
@@ skipping 38 matching lines @@
       break;
     default:
       UNREACHABLE();
       return;
   }
 
   if (Bytecodes::IsRegisterOperandType(op_type)) {
     Register register_value = bytecode_iter.GetRegisterOperand(op_index);
     stream << 'R';
     if (op_size != OperandSize::kByte) stream << size_tag;
-    stream << '(' << register_value.index() << ')';
+    if (register_value.is_new_target()) {
+      stream << "(new_target)";
+    } else if (register_value.is_current_context()) {
+      stream << "(context)";
+    } else if (register_value.is_function_closure()) {
+      stream << "(closure)";
+    } else {
+      stream << '(' << register_value.index() << ')';

[rmcilroy, 2016/02/16 16:43:48]

Just realized, could you also special case parameter registers (e.g,
is_parameter() -> "arg" << register_value.ToParameterIndex(parameter_count)

You will need to pass in the function's parameter_count (which is accessable as
bytecode_array()->parameter_count() 

[Stefano Sanfilippo, 2016/02/16 20:28:26]

Done.

If I understand correctly, the format you expected is like R(arg1), R(arg2),
etc. Right?

[rmcilroy, 2016/02/17 10:16:59]

Yes. Could you also special-case <this> e.g., see Register::ToString. 

[Stefano Sanfilippo, 2016/02/17 14:32:28]

Done.

+    }
   } else {
     stream << 'U' << size_tag << '(';
 
     if (Bytecodes::IsImmediateOperandType(op_type)) {
       // We need a cast, otherwise the result is printed as char.
       stream << static_cast<int>(bytecode_iter.GetImmediateOperand(op_index));
     } else if (Bytecodes::IsRegisterCountOperandType(op_type)) {
       stream << bytecode_iter.GetRegisterCountOperand(op_index);
     } else if (Bytecodes::IsIndexOperandType(op_type)) {
       stream << bytecode_iter.GetIndexOperand(op_index);
@@ skipping 104 matching lines @@
   std::stringstream body_stream(body);
   std::string body_line;
   while (std::getline(body_stream, body_line)) {
     stream << "  ";
     PrintEscapedString(stream, body_line);
     stream << '\n';
   }
   stream << "\"\n";
 }
 
+void BytecodeExpectationsPrinter::PrintHandlers(
+    std::ostream& stream, i::Handle<i::BytecodeArray> bytecode_array) const {
+  stream << "handlers: [\n";
+  HandlerTable* table = HandlerTable::cast(bytecode_array->handler_table());
+  for (int i = 0, num_entries = table->NumberOfRangeEntries(); i < num_entries;
+       ++i) {
+    stream << "  [" << table->GetRangeStart(i) << ", " << table->GetRangeEnd(i)
+           << ", " << table->GetRangeHandler(i) << "],\n";
+  }
+  stream << "]\n";
+}
+
 void BytecodeExpectationsPrinter::PrintBytecodeArray(
     std::ostream& stream, const std::string& body,
     i::Handle<i::BytecodeArray> bytecode_array) const {
   stream << "---\n";
   PrintCodeSnippet(stream, body);
   PrintFrameSize(stream, bytecode_array);
   PrintBytecodeSequence(stream, bytecode_array);
   PrintConstantPool(stream, bytecode_array->constant_pool());
-
-  // TODO(ssanfilippo) print handlers.
-  i::HandlerTable* handlers =
-      i::HandlerTable::cast(bytecode_array->handler_table());
-  CHECK_EQ(handlers->NumberOfRangeEntries(), 0);
+  PrintHandlers(stream, bytecode_array);
 }
 
 void BytecodeExpectationsPrinter::PrintExpectation(
     std::ostream& stream, const std::string& snippet) const {
-  const char* wrapper_function_name = "__genbckexp_wrapper__";
+  std::string source_code =
+      wrap_ ? WrapCodeInFunction(top_function_name_.c_str(), snippet) : snippet;
 
-  std::string source_code = WrapCodeInFunction(wrapper_function_name, snippet);
-  CompileAndRun(source_code.c_str());
+  v8::Local<v8::Script> script = Compile(source_code.c_str());
+
+  if (execute_) Run(script);

[rmcilroy, 2016/02/16 16:43:48]

Out of interest, when do you not want to run the code?

[Stefano Sanfilippo, 2016/02/16 20:28:26]

Apparently, MakeTopLevelBytecode does not run the code after compiling it (and
it does not wrap it either). That behaviour is recreated in our case by setting
both wrap_ and execute_ to false.

[rmcilroy, 2016/02/17 10:16:59]

Ahh I see, yeah you are right, top level code will get compiled to bytecode even
if not executed. 

[Stefano Sanfilippo, 2016/02/17 14:32:28]

Done.

 
   i::Handle<i::BytecodeArray> bytecode_array =
-      GetBytecodeArrayForGlobal(wrapper_function_name);
+      GetBytecodeArrayForGlobal(top_function_name_.c_str());
 
   PrintBytecodeArray(stream, snippet, bytecode_array);
   stream << '\n';
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8