v8/test/cctest/interpreter/test-source-positions.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/v8.h"

#include "src/compiler/pipeline.h"
#include "src/handles.h"
#include "src/interpreter/bytecode-generator.h"
#include "src/interpreter/interpreter.h"
#include "src/isolate.h"
#include "src/parsing/parser.h"
#include "test/cctest/cctest.h"
#include "test/cctest/interpreter/source-position-matcher.h"

namespace v8 {
namespace internal {
namespace interpreter {

// Flags enabling optimizations that change generated bytecode array.
// Format is <command-line flag> <flag name> <bit index>
#define OPTIMIZATION_FLAGS(V)      \
  V(FLAG_ignition_reo, kUseReo, 0) \
  V(FLAG_ignition_peephole, kUsePeephole, 1)

#define DECLARE_BIT(_, Name, BitIndex) static const int Name = 1 << BitIndex;
OPTIMIZATION_FLAGS(DECLARE_BIT)
#undef DECLARE_BIT

// Test cases source positions are checked for. Please ensure all
// combinations of flags are present here. This is done manually
// because it provides easier to comprehend failure case for humans.
#define TEST_CASES(V)                            \
  V(UsingReo, kUseReo)                           \
  V(UsingReoAndPeephole, kUseReo | kUsePeephole) \
  V(UsingPeephole, kUsePeephole)

static const char* kTestScripts[] = {
    "var x = (y = 3) + (x = y); return x + y;",

    "var x = 55;\n"
    "var y = x + (x = 1) + (x = 2) + (x = 3);\n"
    "return y;",

    "var x = 10; return x >>> 3;",

    "var x = 0; return x || (1, 2, 3);",

    "return a || (a, b, a, b, c = 5, 3); ",

    "var a = 3; var b = 4; a = b; b = a; a = b; return a;",

    "var a = 1; return [[a, 2], [a + 2]];",

    "var a = 1; if (a || a < 0) { return 1; }",

    "var b;"
    "b = a.name;"
    "b = a.name;"
    "a.name = a;"
    "b = a.name;"
    "a.name = a;"
    "return b;",

    "var sum = 0;\n"
    "outer: {\n"
    "  for (var x = 0; x < 10; ++x) {\n"
    "    for (var y = 0; y < 3; ++y) {\n"
    "      ++sum;\n"
    "      if (x + y == 12) { break outer; }\n"
    "    }\n"
    "  }\n"
    "}\n"
    "return sum;\n",

    "var a = 1;"
    "switch (a) {"
    "  case 1: return a * a + 1;"
    "  case 1: break;"
    "  case 2: return (a = 3) * a + (a = 4);"
    "  case 3:"
    "}"
    "return a;",

    "for (var p of [0, 1, 2]) {}",

    "var x = { 'a': 1, 'b': 2 };"
    "for (x['a'] of [1,2,3]) { return x['a']; }",

    "while (x == 4) {\n"
    "  var y = x + 1;\n"
    "  if (y == 2) break;\n"
    "  for (z['a'] of [0]) {\n"
    "    x += (x *= 3) + y;"
    "  }\n"
    "}\n",

    "function g(a, b) { return a.func(b + b, b); }\n"
    "g(new (function Obj() { this.func = function() { return; }})(), 1)\n"};

class OptimizedBytecodeSourcePositionTester final {
 public:
  explicit OptimizedBytecodeSourcePositionTester(Isolate* isolate)
      : isolate_(isolate) {
    SaveOptimizationFlags();
    saved_flag_ignition_ = FLAG_ignition;
    FLAG_ignition = true;
    saved_flag_always_opt_ = FLAG_always_opt;
    FLAG_always_opt = false;
  }

  ~OptimizedBytecodeSourcePositionTester() {
    RestoreOptimizationFlags();
    FLAG_ignition = saved_flag_ignition_;
    FLAG_always_opt = saved_flag_always_opt_;
  }

  bool SourcePositionsMatch(int optimization_bitmap, const char* function_body,
                            const char* function_decl_params = "",
                            const char* function_args = "");

 private:
  Handle<BytecodeArray> MakeBytecode(int optimization_bitmap,
                                     const char* function_body,
                                     const char* function_decl_params,
                                     const char* function_args);
  static std::string MakeFunctionName(int optimization_bitmap);
  static std::string MakeScript(const char* function_name,
                                const char* function_body,
                                const char* function_decl_params,
                                const char* function_args);

  void SetOptimizationFlags(int optimization_bitmap);
  void SaveOptimizationFlags();
  void RestoreOptimizationFlags();

  Isolate* isolate() const { return isolate_; }

  Isolate* isolate_;
  int saved_optimization_bitmap_;
  bool saved_flag_ignition_;
  bool saved_flag_always_opt_;
};

// static
std::string OptimizedBytecodeSourcePositionTester::MakeFunctionName(
    int optimization_bitmap) {
  std::ostringstream os;
  os << "test_function_" << optimization_bitmap;
  return os.str();
}

// static
std::string OptimizedBytecodeSourcePositionTester::MakeScript(
    const char* function_name, const char* function_body,
    const char* function_decl_params, const char* function_args) {
  std::ostringstream os;
  os << "function " << function_name << "(" << function_decl_params << ") {";
  os << function_body;
  os << "}";
  os << function_name << "(" << function_args << ");";
  return os.str();
}

Handle<BytecodeArray> OptimizedBytecodeSourcePositionTester::MakeBytecode(
    int optimization_bitmap, const char* function_body,
    const char* function_decl_params, const char* function_args) {
  std::string function_name = MakeFunctionName(optimization_bitmap);
  std::string script = MakeScript(function_name.c_str(), function_body,
                                  function_decl_params, function_args);
  SetOptimizationFlags(optimization_bitmap);
  CompileRun(script.c_str());

  Local<Function> api_function =
      Local<Function>::Cast(CcTest::global()
                                ->Get(CcTest::isolate()->GetCurrentContext(),
                                      v8_str(function_name.c_str()))
                                .ToLocalChecked());
  Handle<JSFunction> function =
      Handle<JSFunction>::cast(v8::Utils::OpenHandle(*api_function));
  return handle(function->shared()->bytecode_array());
}

void OptimizedBytecodeSourcePositionTester::SetOptimizationFlags(
    int optimization_bitmap) {
#define SET_FLAG(V8Flag, BitName, _) \
  V8Flag = (optimization_bitmap & BitName) ? true : false;
  OPTIMIZATION_FLAGS(SET_FLAG)
#undef SET_FLAG
}

void OptimizedBytecodeSourcePositionTester::SaveOptimizationFlags() {
  saved_optimization_bitmap_ = 0;
#define SAVE_FLAG(V8Flag, BitName, _) \
  if (V8Flag) saved_optimization_bitmap_ |= BitName;
#undef SET_FLAG
}

void OptimizedBytecodeSourcePositionTester::RestoreOptimizationFlags() {
  SetOptimizationFlags(saved_optimization_bitmap_);
}

bool OptimizedBytecodeSourcePositionTester::SourcePositionsMatch(
    int optimization_bitmap, const char* function_body,
    const char* function_decl_params, const char* function_args) {
  Handle<BytecodeArray> unoptimized_bytecode =
      MakeBytecode(0, function_body, function_decl_params, function_args);
  Handle<BytecodeArray> optimized_bytecode = MakeBytecode(
      optimization_bitmap, function_body, function_decl_params, function_args);
  SourcePositionMatcher matcher;
  if (!matcher.Match(unoptimized_bytecode, optimized_bytecode)) {
    return false;
  }
  return true;
}

void TestSourcePositionsEquivalent(int optimization_bitmap) {
  HandleAndZoneScope handles;
  // Ensure handler table is generated.
  handles.main_isolate()->interpreter()->Initialize();

  OptimizedBytecodeSourcePositionTester tester(handles.main_isolate());
  for (auto test_script : kTestScripts) {
    CHECK(tester.SourcePositionsMatch(optimization_bitmap, test_script));
  }
}

#define MAKE_TEST(Name, Bitmap)               \
  TEST(TestSourcePositionsEquivalent##Name) { \
    TestSourcePositionsEquivalent(Bitmap);    \
  }
TEST_CASES(MAKE_TEST)
#undef MAKE_TEST

}  // namespace interpreter
}  // namespace internal
}  // namespace v8