[dart_aot_runner] Add support for generating dart_aot snapshots (flutter#13071)

This is part of the effort to port over dart_aot_runner

Author: iskakaushik

shell/platform/fuchsia/BUILD.gn

@@ -20,6 +20,7 @@ if (using_fuchsia_sdk) {
     deps = [
       "dart:kernel_compiler",
       "dart_runner:$dart_runner_target",
+      "dart_runner/embedder:dart_aot_product_snapshot_cc",
       "flutter:flutter_aot_${product_suffix}runner",
       "flutter:flutter_jit_${product_suffix}runner",
       "flutter:flutter_runner_tests",

shell/platform/fuchsia/dart_runner/embedder/BUILD.gn

@@ -2,38 +2,100 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
-import("//build/dart/toolchain.gni")
-import("//topaz/runtime/dart/dart_component.gni")
-import("//topaz/runtime/dart/dart_kernel.gni")
+import("//build/compiled_action.gni")
+import("//third_party/dart/build/dart/dart_action.gni")
+import("$flutter_root/common/fuchsia_config.gni")
+import("$flutter_root/tools/fuchsia/dart.gni")
 
-dart_kernel("shim") {
-  platform_name = "dart_runner"
-  platform_deps = [ "//topaz/runtime/dart_runner/kernel:kernel_platform_files" ]
-  platform_path = "$root_out_dir/dart_runner_patched_sdk"
+template("dart_shim_kernel") {
+  prebuilt_dart_action(target_name) {
+    assert(defined(invoker.main_dart), "main_dart is a required parameter.")
 
-  disable_analysis = true
+    main_dart = rebase_path(invoker.main_dart)
 
-  main_dart = "shim.dart"
+    deps = [
+      "../kernel:kernel_platform_files($host_toolchain)",
+    ]
 
-  aot = true
-  product = false
+    gen_kernel_script = "//third_party/dart/pkg/vm/bin/gen_kernel.dart"
+    platform_dill = "$root_out_dir/dart_runner_patched_sdk/platform_strong.dill"
 
-  visibility = [ ":*" ]
-}
+    dot_packages = rebase_path("//third_party/dart/.packages")
 
-dart_kernel("shim_product") {
-  platform_name = "dart_runner"
-  platform_deps = [ "//topaz/runtime/dart_runner/kernel:kernel_platform_files" ]
-  platform_path = "$root_out_dir/dart_runner_patched_sdk"
+    inputs = [
+      gen_kernel_script,
+      main_dart,
+      dot_packages,
+    ]
 
-  disable_analysis = true
+    output = "$target_gen_dir/$target_name.dill"
+    outputs = [
+      output,
+    ]
 
-  main_dart = "shim.dart"
+    depfile = "$output.d"
+    abs_depfile = rebase_path(depfile)
+    rebased_output = rebase_path(output, root_build_dir)
+    vm_args = [
+      "--depfile=$abs_depfile",
+      "--depfile_output_filename=$rebased_output",
+    ]
+
+    script = gen_kernel_script
+
+    args = [
+      "--packages=" + rebase_path(dot_packages),
+      "--target=dart_runner",
+      "--platform=" + rebase_path(platform_dill),
+      "--no-link-platform",
+      "--output=" + rebase_path(output),
+    ]
+
+    if (is_debug) {
+      args += [ "--embed-sources" ]
+    } else {
+      args += [ "--no-embed-sources" ]
+    }
 
+    if (defined(invoker.aot) && invoker.aot) {
+      args += [
+        "--aot",
+        "--tfa",
+      ]
+    }
+
+    if (defined(invoker.product) && invoker.product) {
+      # Setting this flag in a non-product release build for AOT (a "profile"
+      # build) causes the vm service isolate code to be tree-shaken from an app.
+      # See the pragma on the entrypoint here:
+      #
+      # https://github.com/dart-lang/sdk/blob/master/runtime/bin/vmservice/vmservice_io.dart#L240
+      #
+      # Also, this define excludes debugging and profiling code from Flutter.
+      args += [ "-Ddart.vm.product=true" ]
+    } else {
+      if (!is_debug) {
+        # The following define excludes debugging code from Flutter.
+        args += [ "-Ddart.vm.profile=true" ]
+      }
+    }
+
+    visibility = [ ":*" ]
+
+    args += [ rebase_path(main_dart) ]
+  }
+}
+
+dart_shim_kernel("shim_kernel") {
+  main_dart = "shim.dart"
+  product = false
   aot = true
-  product = true
+}
 
-  visibility = [ ":*" ]
+dart_shim_kernel("shim_product_kernel") {
+  main_dart = "shim.dart"
+  product = true
+  aot = true
 }
 
 template("create_aot_snapshot") {
@@ -42,13 +104,13 @@ template("create_aot_snapshot") {
   if (invoker.product) {
     product_suffix = "_product"
   }
-  action("${target_name}_assembly") {
+  compiled_action("${target_name}_assembly") {
     snapshot_assembly = "$target_gen_dir/aot${product_suffix}_vm_snapshot.S"
 
     # gen_snapshot only needs this to go through the motions of setting up an isolate.
     shim_target = ":shim${product_suffix}_kernel"
     shim_kernel = get_label_info(shim_target, "target_gen_dir") +
-                  "/shim${product_suffix}_kernel.dil"
+                  "/shim${product_suffix}_kernel.dill"
 
     inputs = [
       shim_kernel,
@@ -57,11 +119,13 @@ template("create_aot_snapshot") {
       snapshot_assembly,
     ]
 
-    deps = gen_snapshot_deps + [ shim_target ]
+    deps = [
+      shim_target,
+    ]
     if (invoker.product) {
-      script = gen_snapshot_product
+      tool = gen_snapshot_product
     } else {
-      script = gen_snapshot
+      tool = gen_snapshot
     }
 
     args = [
@@ -74,7 +138,7 @@ template("create_aot_snapshot") {
     # No asserts in debug or release product.
     # No asserts in release with flutter_profile=true (non-product)
     # Yes asserts in non-product debug.
-    if (!invoker.product && (!flutter_profile || is_debug)) {
+    if (!invoker.product && (!(flutter_runtime_mode == "profile") || is_debug)) {
       args += [ "--enable_asserts" ]
     }
     args += [ rebase_path(shim_kernel) ]