Wire up the interpreter on iOS devices. (#2648)

DEPS

@@ -25,7 +25,7 @@ vars = {
 
   # Note: When updating the Dart revision, ensure that all entries that are
   # dependencies of dart are also updated
-  'dart_revision': '14ec00f86bbc893f1c731ea36afb1b98d8cd77cc',
+  'dart_revision': 'e4db01fdd43f019988a901eb51c72790652760a4',
   'dart_boringssl_revision': 'daeafc22c66ad48f6b32fc8d3362eb9ba31b774e',
   'dart_observatory_packages_revision': 'cf90eb9077177d3d6b3fd5e8289477c2385c026a',
   'dart_root_certificates_revision': 'aed07942ce98507d2be28cbd29e879525410c7fc',

sky/build/PackagerInvoke

@@ -51,7 +51,7 @@ PackageProject() {
   AssertExists $src_dir
 
   local precompilation_flag=""
-  if [ $CURRENT_ARCH != "x86_64" ]; then
+  if [[ $CURRENT_ARCH != "x86_64" ]] && [[ "$DART_EXPERIMENTAL_INTERPRETER" != "1" ]]; then
     precompilation_flag="--precompiled"
   fi
 

sky/build/SnapshotterInvoke

@@ -99,6 +99,13 @@ SnapshotProject() {
   fi
   AssertExists $ui_path
 
+  # For dart:jni
+  local jni_path="$(readlink ${packages}/sky_engine)/../sdk_ext/dart_jni/jni.dart"
+  if [[ "${jni_path:0:1}" != "/" ]]; then
+    jni_path="${packages}/${jni_path}"
+  fi
+  AssertExists $jni_path
+
   # For dart:vmservice_sky
   local vm_service_path="$(readlink ${packages}/sky_engine)/../sdk_ext/dart/runtime/bin/vmservice/vmservice_io.dart"
   if [[ "${vm_service_path:0:1}" != "/" ]]; then
@@ -123,20 +130,39 @@ SnapshotProject() {
   RunCommand rm -f ${derived_dir}/kDartIsolateSnapshotBuffer.c
   RunCommand rm -f ${derived_dir}/InstructionsSnapshot.S
 
-  # Finally! Generate the snapshot. The instructions buffer is already in an
-  # assembly file which can be directly used by the linker. For the VM isolate
-  # snapshot buffer and isolate snapshot buffer, we name the file to match
-  # the name of the symbol the VM expects at runtime. On these binary files,
-  # we invoke xxd.
-  #
-  # Note about "checked mode": Precompilation snapshots are never in checked
-  # mode. The flag is also ignored by the standalone VM. So there is no sense
-  # in generating the larger snapshot. For development purposes, a
-  # non-precompilation-enabled VM is used.
-  RunCommand ${FLUTTER_ARCH_TOOLS_PATH}/Snapshotter                            \
+  if [[ $DART_EXPERIMENTAL_INTERPRETER == "1" ]]; then
+    # In case the experimental interpreter is enabled, we need a generic
+    # script snapshot instead of a precompilation snapshot.
+    RunCommand ${FLUTTER_ARCH_TOOLS_PATH}/Snapshotter                          \
       --vm_isolate_snapshot=${derived_dir}/kDartVmIsolateSnapshotBuffer        \
       --isolate_snapshot=${derived_dir}/kDartIsolateSnapshotBuffer             \
-      --assembly=${derived_dir}/InstructionsSnapshot.S            \
+      --package_root=${packages}                                               \
+      --url_mapping=dart:mojo.internal,${mojo_internal_path}                   \
+      --url_mapping=dart:ui,${ui_path}                                         \
+      --url_mapping=dart:jni,${jni_path}                                       \
+      --url_mapping=dart:vmservice_sky,$vm_service_path                        \
+      --conditional_directives                                                 \
+      ${src_dir}/snapshot.dart
+
+    local dummy_snapshot=${derived_dir}/InstructionsSnapshot.S
+    RunCommand rm -f ${dummy_snapshot}
+    RunCommand touch ${dummy_snapshot}
+
+  else
+    # Generate the precompilation snapshot. The instructions buffer is in an
+    # assembly file which can be directly used by the linker. For the VM isolate
+    # snapshot buffer and isolate snapshot buffer, we name the file to match
+    # the name of the symbol the VM expects at runtime. On these binary files,
+    # we invoke xxd.
+    #
+    # Note about "checked mode": Precompilation snapshots are never in checked
+    # mode. The flag is also ignored by the standalone VM. So there is no sense
+    # in generating the larger snapshot. For development purposes, a
+    # non-precompilation-enabled VM is used.
+    RunCommand ${FLUTTER_ARCH_TOOLS_PATH}/Snapshotter                          \
+      --vm_isolate_snapshot=${derived_dir}/kDartVmIsolateSnapshotBuffer        \
+      --isolate_snapshot=${derived_dir}/kDartIsolateSnapshotBuffer             \
+      --assembly=${derived_dir}/InstructionsSnapshot.S                         \
       --embedder_entry_points_manifest=${src_dir}/EmbedderEntryPoints          \
       --package_root=${packages}                                               \
       --url_mapping=dart:mojo.internal,${mojo_internal_path}                   \
@@ -145,6 +171,8 @@ SnapshotProject() {
       --conditional_directives                                                 \
       $main_path
 
+  fi
+
   if [[ $? -ne 0 ]]; then
     EchoError "Snapshotter failed for $1 ..."
     exit -1

sky/build/sdk_xcode_harness/Flutter.xcconfig

@@ -4,4 +4,8 @@
 
 #include "Local.xcconfig"
 
+// This file only exists in case the embedder VM supports the interpreter on the
+// device. If this file is not present, it is not an error.
+#include "Interpreter.xcconfig"
+
 FLUTTER_ARCH_TOOLS_PATH=${SOURCE_ROOT}/Tools/${PLATFORM_NAME}

sky/build/sdk_xcode_harness/FlutterApplication.xcodeproj/project.pbxproj

@@ -18,7 +18,6 @@
 		9E0FB06D1C1A3F5600DDAEFA /* InstructionsSnapshotSource.S in Sources */ = {isa = PBXBuildFile; fileRef = 9E0FB0691C1A3F5600DDAEFA /* InstructionsSnapshotSource.S */; };
 		9E0FB06E1C1A3F5600DDAEFA /* kDartIsolateSnapshotBufferSource.c in Sources */ = {isa = PBXBuildFile; fileRef = 9E0FB06A1C1A3F5600DDAEFA /* kDartIsolateSnapshotBufferSource.c */; };
 		9E0FB06F1C1A3F5600DDAEFA /* kDartVmIsolateSnapshotBufferSource.c in Sources */ = {isa = PBXBuildFile; fileRef = 9E0FB06B1C1A3F5600DDAEFA /* kDartVmIsolateSnapshotBufferSource.c */; };
-		9E40465D1C1B6E9200A4B87C /* icudtl.dat in Resources */ = {isa = PBXBuildFile; fileRef = 9E4046541C1B6A3600A4B87C /* icudtl.dat */; };
 		9E627AD91C582ABB000D800D /* app.flx in Resources */ = {isa = PBXBuildFile; fileRef = 9E627AD81C582ABB000D800D /* app.flx */; };
 		9EA2FB801C6D2D6B00670B03 /* LaunchScreen.storyboard in Resources */ = {isa = PBXBuildFile; fileRef = 9EA2FB7F1C6D2D6B00670B03 /* LaunchScreen.storyboard */; };
 /* End PBXBuildFile section */
@@ -49,7 +48,7 @@
 /* End PBXCopyFilesBuildPhase section */
 
 /* Begin PBXFileReference section */
-		97F908AF1CDC02C500D4520F /* Flutter.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Flutter.framework; path = ../iphonesimulator/Flutter.framework; sourceTree = "<group>"; };
+		97F908AF1CDC02C500D4520F /* Flutter.framework */ = {isa = PBXFileReference; lastKnownFileType = wrapper.framework; name = Flutter.framework; path = ../common/Flutter.framework; sourceTree = "<group>"; };
 		9E07CF861BE7F4D200BCD8DE /* FlutterApplication.framework */ = {isa = PBXFileReference; explicitFileType = wrapper.framework; includeInIndex = 0; path = FlutterApplication.framework; sourceTree = BUILT_PRODUCTS_DIR; };
 		9E07CF891BE7F4D200BCD8DE /* FlutterApplication.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = FlutterApplication.h; sourceTree = "<group>"; };
 		9E07CF8B1BE7F4D200BCD8DE /* Info.plist */ = {isa = PBXFileReference; lastKnownFileType = text.plist.xml; path = Info.plist; sourceTree = "<group>"; };
@@ -65,10 +64,10 @@
 		9E4046501C1B6A3600A4B87C /* EmbedderEntryPoints */ = {isa = PBXFileReference; lastKnownFileType = text; path = EmbedderEntryPoints; sourceTree = "<group>"; };
 		9E4046511C1B6A3600A4B87C /* PackagerInvoke */ = {isa = PBXFileReference; lastKnownFileType = text.script.sh; path = PackagerInvoke; sourceTree = "<group>"; };
 		9E4046531C1B6A3600A4B87C /* SnapshotterInvoke */ = {isa = PBXFileReference; lastKnownFileType = text.script.sh; path = SnapshotterInvoke; sourceTree = "<group>"; };
-		9E4046541C1B6A3600A4B87C /* icudtl.dat */ = {isa = PBXFileReference; lastKnownFileType = file; path = icudtl.dat; sourceTree = "<group>"; };
 		9E4046571C1B6A3600A4B87C /* Snapshotter */ = {isa = PBXFileReference; lastKnownFileType = "compiled.mach-o.executable"; path = Snapshotter; sourceTree = "<group>"; };
 		9E40465A1C1B6A3600A4B87C /* Snapshotter */ = {isa = PBXFileReference; lastKnownFileType = "compiled.mach-o.executable"; path = Snapshotter; sourceTree = "<group>"; };
 		9E40465E1C1B6F7900A4B87C /* Local.xcconfig */ = {isa = PBXFileReference; lastKnownFileType = text.xcconfig; path = Local.xcconfig; sourceTree = "<group>"; };
+		9E5CD2D81CD97EFF00D93CCC /* snapshot.dart */ = {isa = PBXFileReference; lastKnownFileType = text; path = snapshot.dart; sourceTree = "<group>"; };
 		9E627AD81C582ABB000D800D /* app.flx */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = text; name = app.flx; path = Generated/app.flx; sourceTree = "<group>"; };
 		9EA2FB7F1C6D2D6B00670B03 /* LaunchScreen.storyboard */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = file.storyboard; name = LaunchScreen.storyboard; path = ../LaunchScreen.storyboard; sourceTree = SOURCE_ROOT; };
 /* End PBXFileReference section */
@@ -160,10 +159,10 @@
 		9E40464F1C1B6A3600A4B87C /* common */ = {
 			isa = PBXGroup;
 			children = (
+				9E5CD2D81CD97EFF00D93CCC /* snapshot.dart */,
 				9E4046501C1B6A3600A4B87C /* EmbedderEntryPoints */,
 				9E4046511C1B6A3600A4B87C /* PackagerInvoke */,
 				9E4046531C1B6A3600A4B87C /* SnapshotterInvoke */,
-				9E4046541C1B6A3600A4B87C /* icudtl.dat */,
 				97F908AF1CDC02C500D4520F /* Flutter.framework */,
 			);
 			path = common;
@@ -298,7 +297,6 @@
 			isa = PBXResourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
-				9E40465D1C1B6E9200A4B87C /* icudtl.dat in Resources */,
 				9EA2FB801C6D2D6B00670B03 /* LaunchScreen.storyboard in Resources */,
 				9E07CFA91BE8280A00BCD8DE /* Assets.xcassets in Resources */,
 			);
@@ -492,6 +490,7 @@
 				ENABLE_STRICT_OBJC_MSGSEND = YES;
 				GCC_C_LANGUAGE_STANDARD = gnu99;
 				GCC_NO_COMMON_BLOCKS = YES;
+				GCC_PREPROCESSOR_DEFINITIONS = "";
 				GCC_WARN_64_TO_32_BIT_CONVERSION = YES;
 				GCC_WARN_ABOUT_RETURN_TYPE = YES_ERROR;
 				GCC_WARN_UNDECLARED_SELECTOR = YES;

sky/build/sdk_xcode_harness/FlutterApplication.xcodeproj/xcshareddata/xcschemes/Application.xcscheme

@@ -62,18 +62,6 @@
          </BuildableReference>
       </BuildableProductRunnable>
       <CommandLineArguments>
-         <CommandLineArgument
-            argument = "--dart-main=$(FLUTTER_APPLICATION_PATH)/lib/main.dart"
-            isEnabled = "YES">
-         </CommandLineArgument>
-         <CommandLineArgument
-            argument = "--flx=$(FLUTTER_APPLICATION_PATH)/build/app.flx"
-            isEnabled = "YES">
-         </CommandLineArgument>
-         <CommandLineArgument
-            argument = "--packages=$(FLUTTER_APPLICATION_PATH)/.packages"
-            isEnabled = "YES">
-         </CommandLineArgument>
          <CommandLineArgument
             argument = "--observatory-port=8181"
             isEnabled = "YES">

sky/build/sdk_xcode_harness/FlutterApplication/InstructionsSnapshotSource.S

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
 
-#if __arm__ || __aarch64__
+#if (__arm__ || __aarch64__)
 #include "Generated/InstructionsSnapshot.S"
 #endif

sky/build/sdk_xcode_harness/FlutterApplication/kDartIsolateSnapshotBufferSource.c

@@ -2,6 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#if __arm__ || __aarch64__
+#if (__arm__ || __aarch64__)
 #include "Generated/kDartIsolateSnapshotBuffer.c"
 #endif

sky/build/sdk_xcode_harness/FlutterApplication/kDartVmIsolateSnapshotBufferSource.c

@@ -2,6 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#if __arm__ || __aarch64__
+#if (__arm__ || __aarch64__)
 #include "Generated/kDartVmIsolateSnapshotBuffer.c"
 #endif

sky/build/sdk_xcode_harness/Interpreter.xcconfig

+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+DART_EXPERIMENTAL_INTERPRETER=1

sky/build/sky_precompilation_sdk.gni

@@ -2,8 +2,8 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//sky/engine/bindings/bindings.gni")
 import("//build/config/templates/templates.gni")
+import("//sky/engine/bindings/bindings.gni")
 
 template("sky_precompilation_sdk") {
   assert(is_ios, "The precompilation SDK is only supported for iOS targets")
@@ -61,6 +61,7 @@ template("sky_precompilation_sdk") {
     sources = [
       "//sky/build/SnapshotterInvoke",
       "//sky/build/PackagerInvoke",
+      "//sky/engine/bindings/snapshot.dart",
     ]
     outputs = [  "$sdk_dir/$tools_dir/{{source_file_part}}"  ]
   }
@@ -73,6 +74,13 @@ template("sky_precompilation_sdk") {
       "//sky/build/sdk_xcode_harness/Local.xcconfig",
       "//sky/build/sdk_xcode_harness/Runner",
     ]
+
+    if (dart_experimental_interpreter) {
+      sources += [
+        "//sky/build/sdk_xcode_harness/Interpreter.xcconfig",
+      ]
+    }
+
     outputs = [  "$sdk_dir/{{source_file_part}}"  ]
   }
 
@@ -87,41 +95,11 @@ template("sky_precompilation_sdk") {
     outputs = [  "$root_out_dir/{{source_file_part}}"  ]
   }
 
-  executable_gen_target_name = target_name + "_runner"
-  executable(executable_gen_target_name) {
-    libs = [
-      "AudioToolbox.framework",
-      "AVFoundation.framework",
-      "OpenGLES.framework",
-      "QuartzCore.framework",
-      "UIKit.framework",
-    ]
-    deps = [  "//sky/shell:ios_scaffolding"  ]
-  }
-
-  copy_runner_gen_target_name = target_name + "_copy_runner"
-  copy(copy_runner_gen_target_name) {
-    sources = [  "$root_out_dir/$executable_gen_target_name"  ]
-    outputs = [  "$sdk_dir/$arch_tools_dir/FlutterRunner"  ]
-
-    deps = [  ":$executable_gen_target_name"  ]
-  }
-
-  copy_data_gen_target_name = target_name + "_copy_data"
-  copy(copy_data_gen_target_name) {
-    set_sources_assignment_filter([])
-    sources = [  "//third_party/icu/android/icudtl.dat"  ]
-    outputs = [  "$sdk_dir/$tools_dir/{{source_file_part}}"  ]
-    set_sources_assignment_filter(sources_assignment_filter)
-  }
-
   group(target_name) {
     deps = [
       ":copy_snapshotter",
       ":copy_flutter_framework",
       ":embedder_entry_points",
-      ":$copy_runner_gen_target_name",
-      ":$copy_data_gen_target_name",
       ":precompilation_xcode_scripts",
       ":copy_sdk_xcode_harness",
       ":copy_user_editable_files",

sky/engine/core/script/dart_init.cc

@@ -457,6 +457,20 @@ void SetServiceIsolateHook(ServiceIsolateHook hook) {
   g_service_isolate_hook = hook;
 }
 
+static bool ShouldEnableCheckedMode() {
+  if (IsRunningPrecompiledCode()) {
+    // Checked mode is never enabled during precompilation. Even snapshot
+    // generation disables checked mode arguments.
+    return false;
+  }
+
+#if ENABLE(DART_STRICT)
+  return true;
+#else
+  return SkySettings::Get().enable_dart_checked_mode;
+#endif
+}
+
 void InitDartVM() {
   TRACE_EVENT0("flutter", __func__);
 
@@ -468,30 +482,23 @@ void InitDartVM() {
   DartMojoInternal::SetHandleWatcherProducerHandle(
       mojo::dart::HandleWatcher::Start());
 
-  bool enable_checked_mode = SkySettings::Get().enable_dart_checked_mode;
-#if ENABLE(DART_STRICT)
-  enable_checked_mode = true;
-#endif
+  Vector<const char*> args;
 
-  if (IsRunningPrecompiledCode()) {
-    enable_checked_mode = false;
-  }
+  // Instruct the VM to ignore unrecognized flags.
+  // There is a lot of diversity in a lot of combinations when it
+  // comes to the arguments the VM supports. And, if the VM comes across a flag
+  // it does not recognize, it exits immediately.
+  args.append("--ignore-unrecognized-flags");
 
-  Vector<const char*> args;
   args.append(kDartProfilingArgs, arraysize(kDartProfilingArgs));
+  args.append(kDartMirrorsArgs, arraysize(kDartMirrorsArgs));
+  args.append(kDartBackgroundCompilationArgs,
+              arraysize(kDartBackgroundCompilationArgs));
 
-  if (!IsRunningPrecompiledCode()) {
-    // The version of the VM setup to run precompiled code does not recognize
-    // the mirrors or the background compilation flags. They are never enabled.
-    // Make sure we dont pass in unrecognized flags.
-    args.append(kDartMirrorsArgs, arraysize(kDartMirrorsArgs));
-    args.append(kDartBackgroundCompilationArgs,
-                arraysize(kDartBackgroundCompilationArgs));
-  } else {
+  if (IsRunningPrecompiledCode())
     args.append(kDartPrecompilationArgs, arraysize(kDartPrecompilationArgs));
-  }
 
-  if (enable_checked_mode)
+  if (ShouldEnableCheckedMode())
     args.append(kDartCheckedModeArgs, arraysize(kDartCheckedModeArgs));
 
   if (SkySettings::Get().start_paused)
@@ -502,12 +509,9 @@ void InitDartVM() {
 
   Vector<std::string> dart_flags;
   if (base::CommandLine::ForCurrentProcess()->HasSwitch(kDartFlags)) {
-    // Instruct the VM to ignore unrecognized flags.
-    args.append("--ignore-unrecognized-flags");
     // Split up dart flags by spaces.
     base::CommandLine& command_line = *base::CommandLine::ForCurrentProcess();
-    std::stringstream ss(
-        command_line.GetSwitchValueNative(kDartFlags));
+    std::stringstream ss(command_line.GetSwitchValueNative(kDartFlags));
     std::istream_iterator<std::string> it(ss);
     std::istream_iterator<std::string> end;
     while (it != end) {

sky/shell/platform/ios/framework/Headers/FlutterDartProject.h

@@ -20,6 +20,9 @@ FLUTTER_EXPORT
                           packages:(NSURL*)dartPackages
     NS_DESIGNATED_INITIALIZER;
 
+- (instancetype)initWithFLXArchiveWithScriptSnapshot:(NSURL*)archiveURL
+    NS_DESIGNATED_INITIALIZER;
+
 - (instancetype)initFromDefaultSourceForConfiguration;
 
 @end

sky/shell/platform/ios/framework/Source/FlutterAppDelegate.mm

@@ -9,7 +9,6 @@
 
 - (BOOL)application:(UIApplication*)application
     didFinishLaunchingWithOptions:(NSDictionary*)launchOptions {
-
   FlutterDartProject* project =
       [[FlutterDartProject alloc] initFromDefaultSourceForConfiguration];
 
@@ -19,6 +18,7 @@
       [[FlutterViewController alloc] initWithProject:project
                                              nibName:nil
                                               bundle:nil];
+  [project release];
   window.rootViewController = viewController;
   [viewController release];
   self.window = window;
@@ -31,22 +31,28 @@
 // Use the NSNotificationCenter to notify services when we're opened with URLs.
 // TODO(jackson): Revisit this API once we have more services using URLs to make
 // it more typed and less brittle
-- (BOOL)application:(UIApplication *)app
-            openURL:(NSURL *)url
-            sourceApplication:(NSString *)sourceApplication
-            annotation:(id)annotation
-{
-  NSDictionary *dict = [@{
-    @"handled": [NSMutableDictionary dictionary],
-    @"url": url,
-    @"sourceApplication": sourceApplication,
+- (BOOL)application:(UIApplication*)app
+            openURL:(NSURL*)url
+  sourceApplication:(NSString*)sourceApplication
+         annotation:(id)annotation {
+
+  NSDictionary* dict = [@{
+    @"handled" : [NSMutableDictionary dictionary],
+    @"url" : url,
+    @"sourceApplication" : sourceApplication,
   } mutableCopy];
+
   if (annotation != nil)
     [dict setValue:annotation forKey:@"annotation"];
+
   [[NSNotificationCenter defaultCenter] postNotificationName:@"openURL"
                                                       object:self
                                                     userInfo:dict];
-  return ((NSNumber *)dict[@"handled"][@"value"]).boolValue;
+
+  BOOL handled = ((NSNumber*)dict[@"handled"][@"value"]).boolValue;
+  [dict release];
+
+  return handled;
 }
 
 @end

sky/shell/platform/ios/framework/Source/FlutterDartProject.mm

@@ -5,14 +5,11 @@
 #include "sky/shell/platform/ios/framework/Source/FlutterDartProject_Internal.h"
 
 #include "base/command_line.h"
+#include "dart/runtime/include/dart_api.h"
 #include "sky/shell/platform/ios/framework/Source/FlutterDartSource.h"
 #include "sky/shell/switches.h"
 
-namespace {
-
-#if TARGET_IPHONE_SIMULATOR
-
-NSURL* URLForSwitch(const char* name) {
+static NSURL* URLForSwitch(const char* name) {
   auto cmd = *base::CommandLine::ForCurrentProcess();
   NSUserDefaults* defaults = [NSUserDefaults standardUserDefaults];
 
@@ -26,10 +23,6 @@ NSURL* URLForSwitch(const char* name) {
   return [defaults URLForKey:@(name)];
 }
 
-#endif  // TARGET_IPHONE_SIMULATOR
-
-}  // namespace
-
 @implementation FlutterDartProject {
   NSBundle* _precompiledDartBundle;
   FlutterDartSource* _dartSource;
@@ -73,22 +66,60 @@ NSURL* URLForSwitch(const char* name) {
   return self;
 }
 
+- (instancetype)initWithFLXArchiveWithScriptSnapshot:(NSURL*)archiveURL {
+  self = [super init];
+
+  if (self) {
+    _dartSource = [[FlutterDartSource alloc]
+        initWithFLXArchiveWithScriptSnapshot:archiveURL];
+
+    [self checkReadiness];
+  }
+
+  return self;
+}
+
 #pragma mark - Convenience initializers
 
 - (instancetype)initFromDefaultSourceForConfiguration {
-  #if TARGET_IPHONE_SIMULATOR
-    return [self
-        initWithFLXArchive:URLForSwitch(sky::shell::switches::kFLX)
-                  dartMain:URLForSwitch(sky::shell::switches::kMainDartFile)
-                  packages:URLForSwitch(sky::shell::switches::kPackages)];
-  #else
-    NSString* bundlePath =
-        [[NSBundle mainBundle] pathForResource:@"FlutterApplication"
-                                        ofType:@"framework"
-                                   inDirectory:@"Frameworks"];
-    NSBundle* bundle = [NSBundle bundleWithPath:bundlePath];
+  NSString* bundlePath =
+      [[NSBundle mainBundle] pathForResource:@"FlutterApplication"
+                                      ofType:@"framework"
+                                 inDirectory:@"Frameworks"];
+  NSBundle* bundle = [NSBundle bundleWithPath:bundlePath];
+
+  // In both precompilation and non-precompilation cases, we need to bundle
+  // loaded since at least the FLX archive is present in it.
+  [bundle load];
+
+  if (Dart_IsPrecompiledRuntime()) {
+    // Load from an AOTC snapshot.
     return [self initWithPrecompiledDartBundle:bundle];
-  #endif
+  } else {
+    // Load directly from sources if the appropriate command line flags are
+    // specified. If not, try loading from a script snapshot in the framework
+    // bundle.
+    NSURL* flxURL = URLForSwitch(sky::shell::switches::kFLX);
+
+    if (flxURL == nil) {
+      // If the URL was not specified on the command line, look inside the
+      // FlutterApplication bundle.
+      flxURL =
+          [NSURL fileURLWithPath:[bundle pathForResource:@"app" ofType:@"flx"]
+                     isDirectory:NO];
+    }
+
+    NSURL* dartMainURL = URLForSwitch(sky::shell::switches::kMainDartFile);
+    NSURL* dartPackagesURL = URLForSwitch(sky::shell::switches::kPackages);
+
+    return [self initWithFLXArchive:flxURL
+                           dartMain:dartMainURL
+                           packages:dartPackagesURL];
+  }
+
+  NSAssert(NO, @"Unreachable");
+  [self release];
+  return nil;
 }
 
 #pragma mark - Common initialization tasks
@@ -202,9 +233,15 @@ static NSString* NSStringFromVMType(VMType type) {
       return result(NO, message);
     }
 
-    engine->RunFromFile(_dartSource.dartMain.absoluteURL.path.UTF8String,
-                        _dartSource.packages.absoluteURL.path.UTF8String,
-                        _dartSource.flxArchive.absoluteURL.path.UTF8String);
+    if (_dartSource.archiveContainsScriptSnapshot) {
+      engine->RunFromBundle("file://script_snapshot",
+                            _dartSource.flxArchive.absoluteURL.path.UTF8String);
+    } else {
+      engine->RunFromFile(_dartSource.dartMain.absoluteURL.path.UTF8String,
+                          _dartSource.packages.absoluteURL.path.UTF8String,
+                          _dartSource.flxArchive.absoluteURL.path.UTF8String);
+    }
+
     result(YES, @"Success");
   }];
 }

sky/shell/platform/ios/framework/Source/FlutterDartSource.h

@@ -14,11 +14,15 @@ typedef void (^ValidationResult)(BOOL result, NSString* message);
 @property(nonatomic, readonly) NSURL* dartMain;
 @property(nonatomic, readonly) NSURL* packages;
 @property(nonatomic, readonly) NSURL* flxArchive;
+@property(nonatomic, readonly) BOOL archiveContainsScriptSnapshot;
 
 - (instancetype)initWithDartMain:(NSURL*)dartMain
                         packages:(NSURL*)packages
                       flxArchive:(NSURL*)flxArchive NS_DESIGNATED_INITIALIZER;
 
+- (instancetype)initWithFLXArchiveWithScriptSnapshot:(NSURL*)flxArchive
+    NS_DESIGNATED_INITIALIZER;
+
 - (void)validate:(ValidationResult)result;
 
 @end

sky/shell/platform/ios/framework/Source/FlutterDartSource.mm

@@ -4,16 +4,22 @@
 
 #include "sky/shell/platform/ios/framework/Source/FlutterDartSource.h"
 
-@implementation FlutterDartSource {
-  NSURL* _dartMain;
-  NSURL* _packages;
-  NSURL* _flxArchive;
-}
+@implementation FlutterDartSource
+
+@synthesize dartMain=_dartMain;
+@synthesize packages=_packages;
+@synthesize flxArchive=_flxArchive;
+@synthesize archiveContainsScriptSnapshot=_archiveContainsScriptSnapshot;
+
+#pragma mark - Convenience Initializers
 
 - (instancetype)init {
   return [self initWithDartMain:nil packages:nil flxArchive:nil];
 }
 
+
+#pragma mark - Designated Initializers
+
 - (instancetype)initWithDartMain:(NSURL*)dartMain
                         packages:(NSURL*)packages
                       flxArchive:(NSURL*)flxArchive {
@@ -23,6 +29,30 @@
     _dartMain = [dartMain copy];
     _packages = [packages copy];
     _flxArchive = [flxArchive copy];
+
+    NSFileManager* fileManager = [NSFileManager defaultManager];
+
+    const BOOL dartMainExists =
+        [fileManager fileExistsAtPath:dartMain.absoluteURL.path];
+    const BOOL packagesExists =
+        [fileManager fileExistsAtPath:packages.absoluteURL.path];
+
+    if (!dartMainExists || !packagesExists) {
+      // We cannot actually verify this without opening up the archive. This is
+      // just an assumption.
+      _archiveContainsScriptSnapshot = YES;
+    }
+  }
+
+  return self;
+}
+
+- (instancetype)initWithFLXArchiveWithScriptSnapshot:(NSURL*)flxArchive {
+  self = [super init];
+
+  if (self) {
+    _flxArchive = [flxArchive copy];
+    _archiveContainsScriptSnapshot = YES;
   }
 
   return self;
@@ -56,8 +86,11 @@ static BOOL CheckDartProjectURL(NSMutableString* log,
   BOOL isValid = YES;
 
   isValid &= CheckDartProjectURL(log, _flxArchive, @"FLX archive");
-  isValid &= CheckDartProjectURL(log, _dartMain, @"Dart main");
-  isValid &= CheckDartProjectURL(log, _packages, @"Dart packages");
+
+  if (!_archiveContainsScriptSnapshot) {
+    isValid &= CheckDartProjectURL(log, _dartMain, @"Dart main");
+    isValid &= CheckDartProjectURL(log, _packages, @"Dart packages");
+  }
 
   result(isValid, log);
 }

sky/shell/platform/ios/framework/Source/FlutterViewController.mm

@@ -10,6 +10,7 @@
 #include "base/mac/scoped_nsobject.h"
 #include "base/strings/sys_string_conversions.h"
 #include "base/trace_event/trace_event.h"
+#include "dart/runtime/include/dart_api.h"
 #include "mojo/public/cpp/application/connect.h"
 #include "mojo/public/interfaces/application/service_provider.mojom.h"
 #include "sky/engine/wtf/MakeUnique.h"
@@ -23,8 +24,8 @@
 #include "sky/shell/platform/ios/framework/Source/FlutterDynamicServiceLoader.h"
 #include "sky/shell/platform/ios/framework/Source/FlutterView.h"
 #include "sky/shell/platform/mac/platform_mac.h"
-#include "sky/shell/platform/mac/platform_view_mac.h"
 #include "sky/shell/platform/mac/platform_service_provider.h"
+#include "sky/shell/platform/mac/platform_view_mac.h"
 #include "sky/shell/platform/mac/view_service_provider.h"
 #include "sky/shell/platform_view.h"
 #include "sky/shell/shell.h"
@@ -147,13 +148,10 @@ void FlutterInit(int argc, const char* argv[]) {
 
   [self setupPlatformServiceProvider];
 
-  enum VMType type = VMTypeInvalid;
-
-#if TARGET_IPHONE_SIMULATOR
-  type = VMTypeInterpreter;
-#else
-  type = VMTypePrecompilation;
-#endif
+  // We ask the VM to check what it supports.
+  const enum VMType type = Dart_IsPrecompiledRuntime()
+                               ? VMTypePrecompilation
+                               : VMTypeInterpreter;
 
   [_dartProject launchInEngine:_engine
                 embedderVMType:type

sky/tools/gn

@@ -50,6 +50,11 @@ def to_gn_args(args):
     gn_args['is_debug'] = args.debug
     gn_args['is_clang'] = args.clang and args.target_os not in ['android']
 
+
+    ios_target_cpu = 'arm64'
+    if args.ios_force_armv7:
+      ios_target_cpu = 'arm'
+
     if args.target_os == 'android':
         gn_args['target_os'] = 'android'
         aot = not args.develop
@@ -88,6 +93,8 @@ def to_gn_args(args):
     else:
         gn_args['dart_runtime_mode'] = 'develop'
 
+    gn_args['dart_experimental_interpreter'] = args.experimental_interpreter
+
     gn_args['flutter_product_mode'] = (gn_args['dart_runtime_mode'] == 'release')
 
     if args.target_sysroot:
@@ -126,6 +133,7 @@ def parse_args(args):
   # Adding it now unblocks bot/tool work.
   parser.add_argument('--develop', default=True, action='store_true')
   parser.add_argument('--deploy', default=False, dest='develop', action='store_false')
+  parser.add_argument('--experimental-interpreter', default=False, dest='experimental_interpreter', action='store_true')
 
   parser.add_argument('--target-os', type=str, choices=['android', 'ios'])
   parser.add_argument('--android', dest='target_os', action='store_const', const='android')

sky/tools/sky_snapshot/vm.cc

@@ -17,6 +17,11 @@ static const char* kDartArgs[] = {
     "--enable_mirrors=false",
     "--load_deferred_eagerly=true",
     "--conditional_directives",
+    // TODO(chinmaygarde): The experimental interpreter for iOS device targets
+    // does not support all these flags. The build process uses its own version
+    // of this snapshotter. Till support for all these flags is added, make
+    // sure the snapshotter does not error out on unrecognized flags.
+    "--ignore-unrecognized-flags",
 };
 
 void InitDartVM() {