[Reland] [dartdev] Use an AOT snapshot for dds

This change enables use of an AOT snapshot for dds execution.

TEST=ci

Change-Id: I1eba2913a4160dee5de663622aa9106dd1d83c04
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/327710
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Siva Annamalai <asiva@google.com>

pkg/dartdev/lib/src/commands/run.dart

@@ -388,13 +388,23 @@ class _DebuggingSession {
   ) async {
     final sdkDir = dirname(sdk.dart);
     final fullSdk = sdkDir.endsWith('bin');
-    final ddsSnapshot = fullSdk
-        ? sdk.ddsSnapshot
-        : absolute(sdkDir, 'gen', 'dds.dart.snapshot');
     final devToolsBinaries =
         fullSdk ? sdk.devToolsBinaries : absolute(sdkDir, 'devtools');
-    if (!Sdk.checkArtifactExists(ddsSnapshot)) {
-      return false;
+    String snapshotName = fullSdk
+        ? sdk.ddsAotSnapshot
+        : absolute(sdkDir, 'gen', 'dds_aot.dart.snapshot');
+    String execName = sdk.dartAotRuntime;
+    if (!Sdk.checkArtifactExists(snapshotName)) {
+      // An AOT snapshot of dds is not available, we could
+      // be running on the ia32 platform so check for a regular
+      // kernel file being present.
+      snapshotName = fullSdk
+          ? sdk.ddsSnapshot
+          : absolute(sdkDir, 'gen', 'dds.dart.snapshot');
+      if (!Sdk.checkArtifactExists(snapshotName)) {
+        return false;
+      }
+      execName = sdk.dart;
     }
     ServiceProtocolInfo serviceInfo = await Service.getInfo();
     // Wait for VM service to publish its connection info.
@@ -403,10 +413,10 @@ class _DebuggingSession {
       serviceInfo = await Service.getInfo();
     }
     final process = await Process.start(
-      sdk.dart,
+      execName,
       [
         if (debugDds) '--enable-vm-service=0',
-        ddsSnapshot,
+        snapshotName,
         serviceInfo.serverUri.toString(),
         host,
         port,

pkg/dartdev/lib/src/sdk.dart

@@ -52,6 +52,13 @@ class Sdk {
         'dds.dart.snapshot',
       );
 
+  String get ddsAotSnapshot => path.absolute(
+        sdkPath,
+        'bin',
+        'snapshots',
+        'dds_aot.dart.snapshot',
+      );
+
   String get frontendServerSnapshot => path.absolute(
         sdkPath,
         'bin',

pkg/dartdev/test/sdk_test.dart

@@ -26,7 +26,7 @@ void _sdk() {
   });
 
   test('dds snapshot', () {
-    expectFileExists(Sdk().ddsSnapshot);
+    expectSnapshotExists(Sdk().ddsAotSnapshot, Sdk().ddsSnapshot);
   });
 
   test('dart2js snapshot', () {
@@ -45,6 +45,10 @@ void expectFileExists(String path) {
   expect(File(path).existsSync(), isTrue);
 }
 
+void expectSnapshotExists(String aotpath, String jitpath) {
+  expect(File(aotpath).existsSync() || File(jitpath).existsSync(), isTrue);
+}
+
 void expectDirectoryExists(String path) {
   expect(Directory(path).existsSync(), isTrue);
 }

sdk/BUILD.gn

@@ -46,7 +46,7 @@ declare_args() {
 # ........dart2wasm_product.snapshot (if not on ia32)
 # ........dartdev.dart.snapshot (app-jit snapshot or kernel dill file)
 # ........dartdevc.dart.snapshot
-# ........dds.dart.snapshot
+# ........dds_aot.dart.snapshot (AOT snapshot) or dds.dart.snapshot (ia32)
 # ........frontend_server_aot.dart.snapshot (AOT snapshot, if not on ia32)
 # ........frontend_server.dart.snapshot
 # ........gen_kernel.dart.snapshot (if not on ia32)
@@ -116,15 +116,22 @@ _platform_sdk_snapshots = [
     "dartdev",
     "../utils/dartdev:dartdev",
   ],
-  [
-    "dds",
-    "../utils/dds:dds",
-  ],
   [
     "frontend_server",
     "../utils/kernel-service:frontend_server",
   ],
 ]
+if (dart_target_arch != "ia32" && dart_target_arch != "x86") {
+  _platform_sdk_snapshots += [ [
+        "dds_aot",
+        "../utils/dds:dds_aot",
+      ] ]
+} else {
+  _platform_sdk_snapshots += [ [
+        "dds",
+        "../utils/dds:dds",
+      ] ]
+}
 if (dart_snapshot_kind == "app-jit") {
   _platform_sdk_snapshots += [ [
         "kernel-service",

sdk/lib/_internal/vm/bin/vmservice_io.dart

@@ -81,11 +81,24 @@ class _DebuggingSession {
 
     final fullSdk = dartDir.endsWith('bin');
 
-    final ddsSnapshot = [
+    final dartAotPath = [
+      dartDir,
+      fullSdk ? 'dartaotruntime' : 'dart_precompiled_runtime_product',
+    ].join('/');
+    String snapshotName = [
       dartDir,
       fullSdk ? 'snapshots' : 'gen',
-      'dds.dart.snapshot',
+      'dds_aot.dart.snapshot',
     ].join('/');
+    String execName = dartAotPath;
+    if (!File(snapshotName).existsSync()) {
+      snapshotName = [
+        dartDir,
+        fullSdk ? 'snapshots' : 'gen',
+        'dds.dart.snapshot',
+      ].join('/');
+      execName = dartPath.toString();
+    }
 
     final devToolsBinaries = [
       dartDir,
@@ -95,9 +108,9 @@ class _DebuggingSession {
 
     const enableLogging = false;
     _process = await Process.start(
-      dartPath.toString(),
+      execName,
       [
-        ddsSnapshot,
+        snapshotName,
         server!.serverAddress!.toString(),
         host,
         port,

utils/dds/BUILD.gn

@@ -2,12 +2,17 @@
 # for details. All rights reserved. Use of this source code is governed by a
 # BSD-style license that can be found in the LICENSE file.
 
+import("../aot_snapshot.gni")
 import("../application_snapshot.gni")
 
 group("dds") {
   public_deps = [ ":copy_dds_snapshot" ]
 }
 
+group("dds_aot") {
+  public_deps = [ ":copy_dds_aot_snapshot" ]
+}
+
 copy("copy_dds_snapshot") {
   visibility = [ ":dds" ]
   public_deps = [ ":generate_dds_snapshot" ]
@@ -15,8 +20,28 @@ copy("copy_dds_snapshot") {
   outputs = [ "$root_out_dir/dds.dart.snapshot" ]
 }
 
+copy("copy_dds_aot_snapshot") {
+  visibility = [ ":dds_aot" ]
+  public_deps = [ ":generate_dds_aot_snapshot" ]
+  sources = [ "$root_gen_dir/dds_aot.dart.snapshot" ]
+  outputs = [ "$root_out_dir/dds_aot.dart.snapshot" ]
+}
+
 application_snapshot("generate_dds_snapshot") {
   main_dart = "../../pkg/dds/bin/dds.dart"
   training_args = []
   output = "$root_gen_dir/dds.dart.snapshot"
 }
+
+aot_snapshot("generate_dds_aot_snapshot") {
+  main_dart = "../../pkg/dds/bin/dds.dart"
+  output = "$root_gen_dir/dds_aot.dart.snapshot"
+
+  # dartaotruntime has dart_product_config applied to it,
+  # so it is built in # product mode in both release and
+  # product builds, and is only built in debug mode in debug
+  # builds. The following line ensures that the dartaotruntime
+  # and frontend_server_aot snapshot in an SDK build are
+  # always compatible with each other.
+  force_product_mode = !dart_debug
+}