[interpreter] Ensure optimizations preserve source positions.

test/cctest/interpreter/test-source-positions.cc

Index: test/cctest/interpreter/test-source-positions.cc
diff --git a/test/cctest/interpreter/test-source-positions.cc b/test/cctest/interpreter/test-source-positions.cc
new file mode 100644
index 0000000000000000000000000000000000000000..20bb4404d9cbb652c3cb934bd81a5851a6e132f7
--- /dev/null
+++ b/test/cctest/interpreter/test-source-positions.cc
@@ -0,0 +1,237 @@
+// 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