[flutter_runner] Generate symbols for the Dart VM profiler

ci/licenses_golden/licenses_flutter

@@ -971,6 +971,7 @@ FILE: ../../../flutter/shell/platform/fuchsia/flutter/vulkan_surface_pool.cc
 FILE: ../../../flutter/shell/platform/fuchsia/flutter/vulkan_surface_pool.h
 FILE: ../../../flutter/shell/platform/fuchsia/flutter/vulkan_surface_producer.cc
 FILE: ../../../flutter/shell/platform/fuchsia/flutter/vulkan_surface_producer.h
+FILE: ../../../flutter/shell/platform/fuchsia/runtime/dart/profiler_symbols/dart_profiler_symbols.dart
 FILE: ../../../flutter/shell/platform/fuchsia/runtime/dart/utils/files.cc
 FILE: ../../../flutter/shell/platform/fuchsia/runtime/dart/utils/files.h
 FILE: ../../../flutter/shell/platform/fuchsia/runtime/dart/utils/handle_exception.cc

shell/platform/fuchsia/flutter/BUILD.gn

@@ -99,7 +99,10 @@ template("jit_runner") {
     ]
 
     if (!product) {
-      deps += [ engine_observatory_target ]
+      deps += [
+        "$flutter_root/shell/platform/fuchsia/runtime/dart/profiler_symbols:flutter_jit_runner",
+        engine_observatory_target,
+      ]
     }
 
     binary = "flutter_jit${product_suffix}_runner"
@@ -119,6 +122,14 @@ template("jit_runner") {
           path = rebase_path(engine_observatory_archive_file)
           dest = "observatory.tar"
         },
+        {
+          path = rebase_path(
+                  get_label_info(
+                      "$flutter_root/shell/platform/fuchsia/runtime/dart/profiler_symbols:flutter_jit_runner",
+                      "target_gen_dir") +
+                  "/flutter_jit_runner.dartprofilersymbols")
+          dest = "flutter_jit_runner.dartprofilersymbols"
+        },
       ]
     }
 
@@ -169,7 +180,10 @@ template("aot_runner") {
     ]
 
     if (!product) {
-      deps += [ engine_observatory_target ]
+      deps += [
+        "$flutter_root/shell/platform/fuchsia/runtime/dart/profiler_symbols:flutter_aot_runner",
+        engine_observatory_target,
+      ]
     }
 
     meta_dir = "$flutter_root/shell/platform/fuchsia/flutter/meta"
@@ -189,6 +203,14 @@ template("aot_runner") {
           path = rebase_path(engine_observatory_archive_file)
           dest = "observatory.tar"
         },
+        {
+          path = rebase_path(
+                  get_label_info(
+                      "$flutter_root/shell/platform/fuchsia/runtime/dart/profiler_symbols:flutter_aot_runner",
+                      "target_gen_dir") +
+                  "/flutter_aot_runner.dartprofilersymbols")
+          dest = "flutter_aot_runner.dartprofilersymbols"
+        },
       ]
     }
 

shell/platform/fuchsia/flutter/runner.cc

@@ -16,6 +16,7 @@
 #include "flutter/fml/make_copyable.h"
 #include "flutter/lib/ui/text/font_collection.h"
 #include "flutter/runtime/dart_vm.h"
+#include "runtime/dart/utils/files.h"
 #include "runtime/dart/utils/vmo.h"
 #include "runtime/dart/utils/vmservice_object.h"
 #include "third_party/icu/source/common/unicode/udata.h"
@@ -87,6 +88,19 @@ static void SetThreadName(const std::string& thread_name) {
                                    thread_name.size());
 }
 
+#if !defined(DART_PRODUCT)
+// Register native symbol information for the Dart VM's profiler.
+static void RegisterProfilerSymbols(const char* symbols_path,
+                                    const char* dso_name) {
+  std::string* symbols = new std::string();
+  if (dart_utils::ReadFileToString(symbols_path, symbols)) {
+    Dart_AddSymbols(dso_name, symbols->data(), symbols->size());
+  } else {
+    FML_LOG(ERROR) << "Failed to load " << symbols_path;
+  }
+}
+#endif  // !defined(DART_PRODUCT)
+
 Runner::Runner(async::Loop* loop)
     : loop_(loop), runner_context_(RunnerContext::CreateFromStartupInfo()) {
 #if !defined(DART_PRODUCT)
@@ -110,6 +124,16 @@ Runner::Runner(async::Loop* loop)
 
   runner_context_->AddPublicService<fuchsia::sys::Runner>(
       std::bind(&Runner::RegisterApplication, this, std::placeholders::_1));
+
+#if !defined(DART_PRODUCT)
+  if (Dart_IsPrecompiledRuntime()) {
+    RegisterProfilerSymbols("pkg/data/flutter_aot_runner.dartprofilersymbols",
+                            "");
+  } else {
+    RegisterProfilerSymbols("pkg/data/flutter_jit_runner.dartprofilersymbols",
+                            "");
+  }
+#endif  // !defined(DART_PRODUCT)
 }
 
 Runner::~Runner() {

shell/platform/fuchsia/runtime/dart/profiler_symbols/BUILD.gn

@@ -0,0 +1,56 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import("//third_party/dart/build/dart/dart_action.gni")
+import("$flutter_root/tools/fuchsia/clang.gni")
+
+template("generate_dart_profiler_symbols") {
+  assert(defined(invoker.library_label), "Must define 'library_label'")
+  assert(defined(invoker.library_path), "Must define 'library_path'")
+  assert(defined(invoker.output), "Must define 'output'")
+
+  prebuilt_dart_action(target_name) {
+    deps = [
+      invoker.library_label,
+    ]
+    inputs = [
+      invoker.library_path,
+    ]
+    outputs = [
+      invoker.output,
+    ]
+
+    script = "dart_profiler_symbols.dart"
+
+    packages = rebase_path("//third_party/dart/.packages")
+
+    args = [
+      "--nm",
+      rebase_path("//fuchsia/toolchain/$host_os/bin/llvm-nm"),
+      "--binary",
+      rebase_path(invoker.library_path),
+      "--output",
+      rebase_path(invoker.output),
+    ]
+  }
+}
+
+generate_dart_profiler_symbols("dart_jit_runner") {
+  library_label =
+      "$flutter_root/shell/platform/fuchsia/dart_runner:dart_jit_runner_bin"
+  library_path = "${root_out_dir}/exe.unstripped/dart_jit_runner"
+  output = "${target_gen_dir}/dart_jit_runner.dartprofilersymbols"
+}
+
+generate_dart_profiler_symbols("flutter_jit_runner") {
+  library_label = "$flutter_root/shell/platform/fuchsia/flutter:jit"
+  library_path = "${root_out_dir}/exe.unstripped/flutter_jit_runner"
+  output = "${target_gen_dir}/flutter_jit_runner.dartprofilersymbols"
+}
+
+generate_dart_profiler_symbols("flutter_aot_runner") {
+  library_label = "$flutter_root/shell/platform/fuchsia/flutter:aot"
+  library_path = "${root_out_dir}/exe.unstripped/flutter_aot_runner"
+  output = "${target_gen_dir}/flutter_aot_runner.dartprofilersymbols"
+}

shell/platform/fuchsia/runtime/dart/profiler_symbols/analysis_options.yaml

@@ -0,0 +1,3 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.

shell/platform/fuchsia/runtime/dart/profiler_symbols/dart_profiler_symbols.dart

@@ -0,0 +1,143 @@
+// Copyright 2013 The Flutter Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// On Fuchsia, in lieu of the ELF dynamic symbol table consumed through dladdr,
+// the Dart VM profiler consumes symbols produced by this tool, which have the
+// format
+//
+// struct {
+//    uint32_t num_entries;
+//    struct {
+//      uint32_t offset;
+//      uint32_t size;
+//      uint32_t string_table_offset;
+//    } entries[num_entries];
+//    const char* string_table;
+// }
+//
+// Entries are sorted by offset. String table entries are NUL-terminated.
+//
+// See also //third_party/dart/runtime/vm/native_symbol_fuchsia.cc
+
+import "dart:convert";
+import "dart:io";
+import "dart:typed_data";
+
+import "package:args/args.dart";
+import "package:path/path.dart" as path;
+
+Future<void> main(List<String> args) async {
+  final parser = new ArgParser();
+  parser.addOption("nm", help: "Path to `nm` tool");
+  parser.addOption("binary",
+      help: "Path to the ELF file to extract symbols from");
+  parser.addOption("output", help: "Path to output symbol table");
+  final usage = """
+Usage: dart_profiler_symbols.dart [options]
+
+Options:
+${parser.usage};
+""";
+
+  String buildIdDir;
+  String buildIdScript;
+  String nm;
+  String binary;
+  String output;
+
+  try {
+    final options = parser.parse(args);
+    nm = options["nm"];
+    if (nm == null) {
+      throw "Must specify --nm";
+    }
+    if (!FileSystemEntity.isFileSync(nm)) {
+      throw "Cannot find $nm";
+    }
+    binary = options["binary"];
+    if (binary == null) {
+      throw "Must specify --binary";
+    }
+    if (!FileSystemEntity.isFileSync(binary)) {
+      throw "Cannot find $binary";
+    }
+    output = options["output"];
+    if (output == null) {
+      throw "Must specify --output";
+    }
+  } catch (e) {
+    print("ERROR: $e\n");
+    print(usage);
+    exitCode = 1;
+    return;
+  }
+
+  await run(buildIdDir, buildIdScript, nm, binary, output);
+}
+
+class Symbol {
+  int offset;
+  int size;
+  String name;
+}
+
+Future<void> run(String buildIdDir, String buildIdScript, String nm,
+  String binary, String output) async {
+  final unstrippedFile = binary;
+  final args = ["--demangle", "--numeric-sort", "--print-size", unstrippedFile];
+  final result = await Process.run(nm, args);
+  if (result.exitCode != 0) {
+    print(result.stdout);
+    print(result.stderr);
+    throw "Command failed: $nm $args";
+  }
+
+  var symbols = new List();
+
+  var regex = new RegExp("([0-9A-Za-z]+) ([0-9A-Za-z]+) (t|T|w|W) (.*)");
+  for (final line in result.stdout.split("\n")) {
+    var match = regex.firstMatch(line);
+    if (match == null) {
+      continue; // Ignore non-text symbols.
+    }
+
+    final symbol = new Symbol();
+
+    // Note that capture groups start at 1.
+    symbol.offset = int.parse(match[1], radix: 16);
+    symbol.size = int.parse(match[2], radix: 16);
+    symbol.name = match[4].split("(")[0];
+
+    if (symbol.name.startsWith("\$")) {
+      continue; // Ignore compiler/assembler temps.
+    }
+
+    symbols.add(symbol);
+  }
+
+  if (symbols.isEmpty) {
+    throw "$unstrippedFile has no symbols";
+  }
+
+  var nameTable = new BytesBuilder();
+  var binarySearchTable = new Uint32List(symbols.length * 3 + 1);
+  var binarySearchTableIndex = 0;
+  binarySearchTable[binarySearchTableIndex++] = symbols.length;
+  // Symbols are sorted by offset because of --numeric-sort.
+  for (var symbol in symbols) {
+    var nameOffset = nameTable.length;
+    nameTable.add(utf8.encode(symbol.name));
+    nameTable.addByte(0);
+    binarySearchTable[binarySearchTableIndex++] = symbol.offset;
+    binarySearchTable[binarySearchTableIndex++] = symbol.size;
+    binarySearchTable[binarySearchTableIndex++] = nameOffset;
+  }
+
+  var file = new File(output);
+  await file.parent.create(recursive: true);
+  var sink = file.openWrite();
+  sink.add(binarySearchTable.buffer.asUint8List());
+  sink.add(nameTable.takeBytes());
+  await sink.close();
+}

shell/platform/fuchsia/runtime/dart/profiler_symbols/pubspec.yaml

@@ -0,0 +1,8 @@
+# Copyright 2013 The Flutter Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+name: profiler_symbols
+version: 0
+description: Extracts a minimal symbols table for the Dart VM profiler
+author: Dart Team <[email protected]>