[vm] Remove script snapshots.

Change-Id: I5bc692b754c0909de4aa5f05af81b074578b16f4
Reviewed-on: https://dart-review.googlesource.com/76706
Reviewed-by: Siva Annamalai <asiva@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>

runtime/bin/dartutils.cc

@@ -55,7 +55,6 @@ const char* const DartUtils::kVMServiceLibURL = "dart:vmservice";
 dart::SimpleHashMap* DartUtils::environment_ = NULL;
 
 MagicNumberData appjit_magic_number = {8, {0xdc, 0xdc, 0xf6, 0xf6, 0, 0, 0, 0}};
-MagicNumberData snapshot_magic_number = {4, {0xf5, 0xf5, 0xdc, 0xdc}};
 MagicNumberData kernel_magic_number = {4, {0x90, 0xab, 0xcd, 0xef}};
 MagicNumberData kernel_list_magic_number = {
     7,
@@ -436,8 +435,6 @@ DartUtils::MagicNumber DartUtils::SniffForMagicNumber(const char* filename) {
     if (file != NULL) {
       RefCntReleaseScope<File> rs(file);
       intptr_t max_magic_length = 0;
-      max_magic_length =
-          Utils::Maximum(max_magic_length, snapshot_magic_number.length);
       max_magic_length =
           Utils::Maximum(max_magic_length, appjit_magic_number.length);
       max_magic_length =
@@ -458,10 +455,6 @@ DartUtils::MagicNumber DartUtils::SniffForMagicNumber(const char* filename) {
 
 DartUtils::MagicNumber DartUtils::SniffForMagicNumber(const uint8_t* buffer,
                                                       intptr_t buffer_length) {
-  if (CheckMagicNumber(buffer, buffer_length, snapshot_magic_number)) {
-    return kSnapshotMagicNumber;
-  }
-
   if (CheckMagicNumber(buffer, buffer_length, appjit_magic_number)) {
     return kAppJITMagicNumber;
   }

runtime/bin/dartutils.h

@@ -222,7 +222,6 @@ class DartUtils {
   static Dart_Handle ResolveScript(Dart_Handle url);
 
   enum MagicNumber {
-    kSnapshotMagicNumber,
     kAppJITMagicNumber,
     kKernelMagicNumber,
     kKernelListMagicNumber,
@@ -649,7 +648,6 @@ struct MagicNumberData {
 };
 
 extern MagicNumberData appjit_magic_number;
-extern MagicNumberData snapshot_magic_number;
 extern MagicNumberData kernel_magic_number;
 extern MagicNumberData kernel_list_magic_number;
 extern MagicNumberData gzip_magic_number;

runtime/bin/loader.cc

@@ -446,10 +446,7 @@ bool Loader::ProcessResultLocked(Loader* loader, Loader::IOResult* result) {
       dart_result = Dart_LoadSource(library, uri, resolved_uri, source, 0, 0);
     } break;
     case Dart_kScriptTag:
-      if (payload_type == DartUtils::kSnapshotMagicNumber) {
-        dart_result = Dart_LoadScriptFromSnapshot(payload, payload_length);
-        reload_extensions = true;
-      } else if (payload_type == DartUtils::kKernelMagicNumber) {
+      if (payload_type == DartUtils::kKernelMagicNumber) {
         // TODO(27590): This code path is only hit when trying to spawn
         // isolates. We currently do not have support for neither
         // `Isolate.spawn()` nor `Isolate.spawnUri()` with kernel-based

runtime/bin/main.cc

@@ -915,7 +915,7 @@ bool RunMainIsolate(const char* script_name, CommandLineOptions* dart_options) {
 
   IsolateData* isolate_data =
       reinterpret_cast<IsolateData*>(Dart_IsolateData(isolate));
-  if (Options::gen_snapshot_kind() == kScript) {
+  if (Options::gen_snapshot_kind() == kKernel) {
     if (vm_run_app_snapshot) {
       Log::PrintErr("Cannot create a script snapshot from an app snapshot.\n");
       // The snapshot would contain references to the app snapshot instead of

runtime/bin/main_options.cc

@@ -25,7 +25,7 @@ namespace bin {
 
 // These strings must match the enum SnapshotKind in main_options.h.
 static const char* kSnapshotKindNames[] = {
-    "none", "script", "app-aot", "app-jit", NULL,
+    "none", "kernel", "app-aot", "app-jit", NULL,
 };
 
 SnapshotKind Options::gen_snapshot_kind_ = kNone;
@@ -461,7 +461,7 @@ int Options::ParseArguments(int argc,
 
   // If --snapshot is given without --snapshot-kind, default to script snapshot.
   if ((snapshot_filename_ != NULL) && (gen_snapshot_kind_ == kNone)) {
-    gen_snapshot_kind_ = kScript;
+    gen_snapshot_kind_ = kKernel;
   }
 
   return 0;

runtime/bin/main_options.h

@@ -68,7 +68,7 @@ namespace bin {
 // This enum must match the strings in kSnapshotKindNames in main_options.cc.
 enum SnapshotKind {
   kNone,
-  kScript,
+  kKernel,
   kAppAOT,
   kAppJIT,
 };

runtime/bin/snapshot_utils.cc

@@ -248,6 +248,7 @@ AppSnapshot* Snapshot::TryReadAppSnapshot(const char* script_name) {
   return NULL;
 }
 
+#if !defined(EXCLUDE_CFE_AND_KERNEL_PLATFORM) && !defined(TESTING)
 static void WriteSnapshotFile(const char* filename,
                               const uint8_t* buffer,
                               const intptr_t size) {
@@ -263,6 +264,7 @@ static void WriteSnapshotFile(const char* filename,
   }
   file->Release();
 }
+#endif
 
 static bool WriteInt64(File* file, int64_t size) {
   return file->WriteFully(&size, sizeof(size));
@@ -354,18 +356,6 @@ void Snapshot::GenerateKernel(const char* snapshot_filename,
 #endif  // !defined(EXCLUDE_CFE_AND_KERNEL_PLATFORM) && !defined(TESTING)
 }
 
-void Snapshot::GenerateScript(const char* snapshot_filename) {
-  // First create a snapshot.
-  uint8_t* buffer = NULL;
-  intptr_t size = 0;
-  Dart_Handle result = Dart_CreateScriptSnapshot(&buffer, &size);
-  if (Dart_IsError(result)) {
-    ErrorExit(kErrorExitCode, "%s\n", Dart_GetError(result));
-  }
-
-  WriteSnapshotFile(snapshot_filename, buffer, size);
-}
-
 void Snapshot::GenerateAppJIT(const char* snapshot_filename) {
 #if defined(TARGET_ARCH_IA32)
   // Snapshots with code are not supported on IA32.

runtime/bin/snapshot_utils.h

@@ -31,7 +31,6 @@ class Snapshot {
   static void GenerateKernel(const char* snapshot_filename,
                              const char* script_name,
                              const char* package_config);
-  static void GenerateScript(const char* snapshot_filename);
   static void GenerateAppJIT(const char* snapshot_filename);
   static void GenerateAppAOTAsBlobs(const char* snapshot_filename,
                                     const uint8_t* shared_data,

runtime/include/dart_api.h

@@ -603,7 +603,7 @@ DART_EXPORT void Dart_IsolateFlagsInitialize(Dart_IsolateFlags* flags);
  *   Isolate.spawn, or the argument to Isolate.spawnUri canonicalized by the
  *   library tag handler of the parent isolate.
  *   The callback is responsible for loading the program by a call to
- *   Dart_LoadScript or Dart_LoadScriptFromSnapshot.
+ *   Dart_LoadScript or Dart_LoadScriptFromKernel.
  * \param main The name of the main entry point this isolate will
  *   eventually run.  This is provided for advisory purposes only to
  *   improve debugging messages.  The main function is not invoked by
@@ -1023,26 +1023,6 @@ Dart_CreateSnapshot(uint8_t** vm_snapshot_data_buffer,
                     uint8_t** isolate_snapshot_data_buffer,
                     intptr_t* isolate_snapshot_data_size);
 
-/**
- * Creates a snapshot of the application script loaded in the isolate.
- *
- * A script snapshot can be used for implementing fast startup of applications
- * (skips the script tokenizing and parsing process). A Snapshot of the script
- * can only be created before any dart code has executed.
- *
- * Requires there to be a current isolate which already has loaded script.
- *
- * \param buffer Returns a pointer to a buffer containing
- *   the snapshot. This buffer is scope allocated and is only valid
- *   until the next call to Dart_ExitScope.
- * \param size Returns the size of the buffer.
- *
- * \return A valid handle if no error occurs during the operation.
- */
-DART_EXPORT DART_WARN_UNUSED_RESULT Dart_Handle
-Dart_CreateScriptSnapshot(uint8_t** script_snapshot_buffer,
-                          intptr_t* script_snapshot_size);
-
 /**
  * Returns whether the buffer contains a snapshot created by
  * Dart_Create*Snapshot.
@@ -2970,22 +2950,6 @@ Dart_LoadScript(Dart_Handle url,
                 intptr_t line_offset,
                 intptr_t col_offset);
 
-/**
- * Loads the root script for current isolate from a script snapshot. The
- * snapshot must have been created by Dart_CreateScriptSnapshot from a VM with
- * the same version.
- *
- * \param buffer A buffer which contains a snapshot of the script. May be
- *    released when this function returns.
- * \param buffer_len Length of the passed in buffer.
- *
- * \return If no error occurs, the Library object corresponding to the root
- *   script is returned. Otherwise an error handle is returned.
- */
-DART_EXPORT Dart_Handle
-Dart_LoadScriptFromSnapshot(const uint8_t* script_snapshot_buffer,
-                            intptr_t script_snapshot_size);
-
 /**
  * Loads the root library for the current isolate.
  *

runtime/tests/vm/vm.status

@@ -64,7 +64,6 @@ cc/IsolateReload_KernelIncrementalCompileGenerics: SkipByDesign
 cc/Mixin_PrivateSuperResolution: Skip
 cc/Mixin_PrivateSuperResolutionCrossLibraryShouldFail: Skip
 dart/appjit_determinism_test: Pass, Fail # Issue 31427 - Lingering non-determinism.
-dart/script_determinism_test: Pass, Fail # Issue 31427 - Lingering non-determinism.
 
 [ $compiler == fasta ]
 dart/data_uri_import_test/badencodeddate: CompileTimeError
@@ -238,7 +237,6 @@ cc/ScriptSnapshotsUpdateSubclasses: Fail, Crash, OK # Script snapshots not suppo
 
 [ ($compiler == dartk || $compiler == dartkb) && ($arch == simarm || $arch == simarm64 || $arch == simdbc || $arch == simdbc64) ]
 dart/appjit*: SkipSlow # DFE too slow
-dart/script_determinism_test: SkipSlow # DFE too slow
 
 # Enabling of dartk for sim{arm,arm64,dbc64} revelaed these test failures, which
 # are to be triaged.  Isolate tests are skipped on purpose due to the usage of
@@ -360,7 +358,6 @@ dart/redirection_type_shuffling_test: SkipByDesign # Imports dart:mirrors
 
 [ $hot_reload || $hot_reload_rollback ]
 dart/appjit*: SkipByDesign # Cannot reload with URI pointing to app snapshot.
-dart/script_determinism_test: SkipByDesign # Cannot reload with URI pointing to script snapshot.
 dart/slow_path_shared_stub_test: SkipSlow # Too slow with --slow-path-triggers-gc flag and not relevant outside precompiled.
 dart/spawn_infinite_loop_test: Skip # We can shutdown an isolate before it reloads.
 dart/spawn_shutdown_test: Skip # We can shutdown an isolate before it reloads.

runtime/vm/dart_api_impl.cc

@@ -1487,40 +1487,6 @@ Dart_CreateSnapshot(uint8_t** vm_snapshot_data_buffer,
   return Api::Success();
 }
 
-DART_EXPORT Dart_Handle
-Dart_CreateScriptSnapshot(uint8_t** script_snapshot_buffer,
-                          intptr_t* script_snapshot_size) {
-  DARTSCOPE(Thread::Current());
-  API_TIMELINE_DURATION(T);
-  Isolate* I = T->isolate();
-  CHECK_NULL(script_snapshot_buffer);
-  CHECK_NULL(script_snapshot_size);
-  if (I->use_dart_frontend()) {
-    return Api::NewError("Script snapshots are not supported in Dart 2");
-  }
-  // Finalize all classes if needed.
-  Dart_Handle state = Api::CheckAndFinalizePendingClasses(T);
-  if (::Dart_IsError(state)) {
-    return state;
-  }
-  Library& lib = Library::Handle(Z, I->object_store()->root_library());
-
-#if defined(DEBUG)
-  I->heap()->CollectAllGarbage();
-  {
-    HeapIterationScope iteration(T);
-    CheckFunctionTypesVisitor check_canonical(T);
-    iteration.IterateObjects(&check_canonical);
-  }
-#endif  // #if defined(DEBUG)
-
-  ScriptSnapshotWriter writer(ApiReallocate);
-  writer.WriteScriptSnapshot(lib);
-  *script_snapshot_buffer = writer.buffer();
-  *script_snapshot_size = writer.BytesWritten();
-  return Api::Success();
-}
-
 DART_EXPORT bool Dart_IsSnapshot(const uint8_t* buffer, intptr_t buffer_size) {
   if (buffer_size < Snapshot::kHeaderSize) {
     return false;
@@ -5074,74 +5040,6 @@ DART_EXPORT Dart_Handle Dart_LoadScript(Dart_Handle url,
 #endif  // defined(DART_PRECOMPILED_RUNTIME)
 }
 
-DART_EXPORT Dart_Handle Dart_LoadScriptFromSnapshot(const uint8_t* buffer,
-                                                    intptr_t buffer_len) {
-#if defined(DART_PRECOMPILED_RUNTIME)
-  return Api::NewError("%s: Cannot compile on an AOT runtime.", CURRENT_FUNC);
-#else
-  DARTSCOPE(Thread::Current());
-  API_TIMELINE_DURATION(T);
-  Isolate* I = T->isolate();
-  StackZone zone(T);
-  if (buffer == NULL) {
-    RETURN_NULL_ERROR(buffer);
-  }
-  if (I->use_dart_frontend()) {
-    return Api::NewError("Script snapshots are not supported in Dart 2");
-  }
-  NoHeapGrowthControlScope no_growth_control;
-
-  const Snapshot* snapshot = Snapshot::SetupFromBuffer(buffer);
-  if (snapshot == NULL) {
-    return Api::NewError(
-        "%s expects parameter 'buffer' to be a script type"
-        " snapshot with a valid length.",
-        CURRENT_FUNC);
-  }
-  if (snapshot->kind() != Snapshot::kScript) {
-    return Api::NewError(
-        "%s expects parameter 'buffer' to be a script type"
-        " snapshot.",
-        CURRENT_FUNC);
-  }
-  if (snapshot->length() != buffer_len) {
-    return Api::NewError("%s: 'buffer_len' of %" Pd " is not equal to %" Pd
-                         " which is the expected length in the snapshot.",
-                         CURRENT_FUNC, buffer_len, snapshot->length());
-  }
-  Library& library = Library::Handle(Z, I->object_store()->root_library());
-  if (!library.IsNull()) {
-    const String& library_url = String::Handle(Z, library.url());
-    return Api::NewError("%s: A script has already been loaded from '%s'.",
-                         CURRENT_FUNC, library_url.ToCString());
-  }
-  CHECK_CALLBACK_STATE(T);
-  CHECK_COMPILATION_ALLOWED(I);
-
-  ASSERT(snapshot->kind() == Snapshot::kScript);
-  NOT_IN_PRODUCT(TimelineDurationScope tds2(T, Timeline::GetIsolateStream(),
-                                            "ScriptSnapshotReader"));
-
-  ScriptSnapshotReader reader(snapshot->content(), snapshot->length(), T);
-  const Object& tmp = Object::Handle(Z, reader.ReadScriptSnapshot());
-  if (tmp.IsError()) {
-    return Api::NewHandle(T, tmp.raw());
-  }
-#if !defined(PRODUCT)
-  if (tds2.enabled()) {
-    tds2.SetNumArguments(2);
-    tds2.FormatArgument(0, "snapshotSize", "%" Pd, snapshot->length());
-    tds2.FormatArgument(1, "heapSize", "%" Pd64,
-                        I->heap()->UsedInWords(Heap::kOld) * kWordSize);
-  }
-#endif  // !defined(PRODUCT)
-  library ^= tmp.raw();
-  library.set_debuggable(true);
-  I->object_store()->set_root_library(library);
-  return Api::NewHandle(T, library.raw());
-#endif  // defined(DART_PRECOMPILED_RUNTIME)
-}
-
 DART_EXPORT Dart_Handle Dart_LoadScriptFromKernel(const uint8_t* buffer,
                                                   intptr_t buffer_size) {
 #if defined(DART_PRECOMPILED_RUNTIME)

runtime/vm/dart_api_message.cc

@@ -504,7 +504,6 @@ Dart_CObject* ApiMessageReader::ReadInternalVMObject(intptr_t class_id,
                                                      intptr_t object_id) {
   switch (class_id) {
     case kClassCid: {
-      Read<bool>();  // Consume the is_in_fullsnapshot indicator.
       Dart_CObject_Internal* object = AllocateDartCObjectClass();
       AddBackRef(object_id, object, kIsDeserialized);
       object->internal.as_class.library_url = ReadObjectImpl();

runtime/vm/object_store.h

@@ -231,7 +231,6 @@ class ObjectStore {
       case Snapshot::kFullJIT:
       case Snapshot::kFullAOT:
         return reinterpret_cast<RawObject**>(&megamorphic_miss_function_);
-      case Snapshot::kScript:
       case Snapshot::kMessage:
       case Snapshot::kNone:
       case Snapshot::kInvalid: