Remove android stack_size_test (#153695)

This test expects to run on 32-bit hardware, but the devicelab no longer
has 32-bit Android hardware. In particular, the test contains hand-coded
32-bit arm assembly for reading the stack pointer from Dart code via
`dart:ffi`.

This test was added in response to a framework change that caused stack
frames to be larger than expected while building widgets, leading apps
to crash with StackOverflow exceptions unexpectedly. Since then (>3
years ago) this test has not prevented any similar issue, so I believe
deleting it rather than fixing it is a better use of resources.

.ci.yaml

@@ -2116,17 +2116,6 @@ targets:
         ["devicelab", "android", "linux", "pixel", "7pro"]
       task_name: android_semantics_integration_test
 
-  # linux mokey test
-  - name: Linux_mokey android_stack_size_test
-    recipe: devicelab/devicelab_drone
-    presubmit: false
-    bringup: true # https://github.com/flutter/flutter/issues/148085
-    timeout: 60
-    properties:
-      tags: >
-        ["devicelab", "android", "linux", "mokey"]
-      task_name: android_stack_size_test
-
   # linux mokey benchmark
   - name: Linux_mokey android_view_scroll_perf__timeline_summary
     recipe: devicelab/devicelab_drone

dev/benchmarks/macrobenchmarks/lib/common.dart

@@ -27,7 +27,6 @@ const String kHeavyGridViewRouteName = '/heavy_gridview';
 const String kRasterCacheUseMemory = '/raster_cache_use_memory';
 const String kShaderMaskCacheRouteName = '/shader_mask_cache';
 const String kSimpleScrollRouteName = '/simple_scroll';
-const String kStackSizeRouteName = '/stack_size';
 const String kAnimationWithMicrotasksRouteName = '/animation_with_microtasks';
 const String kAnimatedImageRouteName = '/animated_image';
 const String kOpacityPeepholeRouteName = '/opacity_peephole';
@@ -62,5 +61,3 @@ const String kGradientPerfStaticConsistentRouteName = '$kGradientPerfRouteName/s
 const String kScrollableName = '/macrobenchmark_listview';
 const String kOpacityScrollableName = '$kOpacityPeepholeRouteName/listview';
 const String kGradientPerfScrollableName = '$kGradientPerfRouteName/listview';
-
-const String kStackSizeKey = 'stack_size';

dev/benchmarks/macrobenchmarks/lib/main.dart

@@ -41,7 +41,6 @@ import 'src/shader_mask_cache.dart';
 import 'src/simple_animation.dart';
 import 'src/simple_scroll.dart';
 import 'src/sliders.dart';
-import 'src/stack_size.dart';
 import 'src/text.dart';
 import 'src/very_long_picture_scrolling.dart';
 
@@ -83,7 +82,6 @@ class MacrobenchmarksApp extends StatelessWidget {
         kRasterCacheUseMemory: (BuildContext context) => const RasterCacheUseMemory(),
         kShaderMaskCacheRouteName: (BuildContext context) => const ShaderMaskCachePage(),
         kSimpleScrollRouteName: (BuildContext context) => const SimpleScroll(),
-        kStackSizeRouteName: (BuildContext context) => const StackSizePage(),
         kAnimationWithMicrotasksRouteName: (BuildContext context) => const AnimationWithMicrotasks(),
         kAnimatedImageRouteName: (BuildContext context) => const AnimatedImagePage(),
         kOpacityPeepholeRouteName: (BuildContext context) => const OpacityPeepholePage(),
@@ -279,13 +277,6 @@ class HomePage extends StatelessWidget {
               Navigator.pushNamed(context, kLargeImageChangerRouteName);
             },
           ),
-          ElevatedButton(
-            key: const Key(kStackSizeRouteName),
-            child: const Text('Stack Size'),
-            onPressed: () {
-              Navigator.pushNamed(context, kStackSizeRouteName);
-            },
-          ),
           ElevatedButton(
             key: const Key(kAnimationWithMicrotasksRouteName),
             child: const Text('Animation With Microtasks'),

dev/benchmarks/macrobenchmarks/lib/src/stack_size.dart

@@ -1,129 +0,0 @@
-// Copyright 2014 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 'dart:ffi' as ffi;
-import 'dart:io' as io;
-
-import 'package:flutter/material.dart';
-
-import '../common.dart';
-
-typedef GetStackPointerCallback = int Function();
-
-// c interop function:
-// void* mmap(void* addr, size_t len, int prot, int flags, int fd, off_t offset);
-typedef CMmap = ffi.Pointer<ffi.Void> Function(
-    ffi.Pointer<ffi.Void>, ffi.IntPtr, ffi.Int32, ffi.Int32, ffi.Int32, ffi.IntPtr);
-typedef DartMmap = ffi.Pointer<ffi.Void> Function(
-    ffi.Pointer<ffi.Void>, int, int, int, int, int);
-final DartMmap mmap = ffi.DynamicLibrary.process().lookupFunction<CMmap, DartMmap>('mmap');
-
-// c interop function:
-// int mprotect(void* addr, size_t len, int prot);
-typedef CMprotect = ffi.Int32 Function(ffi.Pointer<ffi.Void>, ffi.IntPtr, ffi.Int32);
-typedef DartMprotect = int Function(ffi.Pointer<ffi.Void>, int, int);
-final DartMprotect mprotect = ffi.DynamicLibrary.process()
-    .lookupFunction<CMprotect, DartMprotect>('mprotect');
-
-const int kProtRead = 1;
-const int kProtWrite = 2;
-const int kProtExec = 4;
-
-const int kMapPrivate = 0x02;
-const int kMapJit = 0x0;
-const int kMapAnon = 0x20;
-
-const int kMemorySize = 16;
-const int kInvalidFileDescriptor = -1;
-const int kkFileMappingOffset = 0;
-
-const int kMemoryStartingIndex = 0;
-
-const int kExitCodeSuccess = 0;
-
-final GetStackPointerCallback getStackPointer = () {
-  // Makes sure we are running on an Android arm64 device.
-  if (!io.Platform.isAndroid) {
-    throw 'This benchmark test can only be run on Android arm devices.';
-  }
-  final io.ProcessResult result = io.Process.runSync('getprop', <String>['ro.product.cpu.abi']);
-  if (result.exitCode != 0) {
-    throw 'Failed to retrieve CPU information.';
-  }
-  if (!result.stdout.toString().contains('armeabi')) {
-    throw 'This benchmark test can only be run on Android arm devices.';
-  }
-
-  // Creates a block of memory to store the assembly code.
-  final ffi.Pointer<ffi.Void> region = mmap(ffi.nullptr, kMemorySize, kProtRead | kProtWrite,
-      kMapPrivate | kMapAnon | kMapJit, kInvalidFileDescriptor, kkFileMappingOffset);
-  if (region == ffi.nullptr) {
-    throw 'Failed to acquire memory for the test.';
-  }
-
-  // Writes the assembly code into the memory block. This assembly code returns
-  // the memory address of the stack pointer.
-  region.cast<ffi.Uint8>().asTypedList(kMemorySize).setAll(
-    kMemoryStartingIndex,
-    <int>[
-      // "mov r0, sp"  in machine code: 0D00A0E1.
-      0x0d, 0x00, 0xa0, 0xe1,
-      // "bx lr"       in machine code: 1EFF2FE1.
-      0x1e, 0xff, 0x2f, 0xe1,
-    ]
-  );
-
-  // Makes sure the memory block is executable.
-  if (mprotect(region, kMemorySize, kProtRead | kProtExec) != kExitCodeSuccess) {
-    throw 'Failed to write executable code to the memory.';
-  }
-  return region
-      .cast<ffi.NativeFunction<ffi.IntPtr Function()>>()
-      .asFunction<int Function()>();
-}();
-
-class StackSizePage extends StatelessWidget {
-  const StackSizePage({super.key});
-
-  @override
-  Widget build(BuildContext context) {
-    return const Material(
-      child: Column(
-        children: <Widget>[
-          SizedBox(
-            width: 200,
-            height: 100,
-            child: ParentWidget(),
-          ),
-        ],
-      ),
-    );
-  }
-}
-
-class ParentWidget extends StatelessWidget {
-  const ParentWidget({super.key});
-
-  @override
-  Widget build(BuildContext context) {
-    final int myStackSize = getStackPointer();
-    return ChildWidget(parentStackSize: myStackSize);
-  }
-}
-
-class ChildWidget extends StatelessWidget {
-  const ChildWidget({required this.parentStackSize, super.key});
-  final int parentStackSize;
-
-  @override
-  Widget build(BuildContext context) {
-    final int myStackSize = getStackPointer();
-    // Captures the stack size difference between parent widget and child widget
-    // during the rendering pipeline, i.e. one layer of stateless widget.
-    return Text(
-      '${parentStackSize - myStackSize}',
-      key: const ValueKey<String>(kStackSizeKey),
-    );
-  }
-}

dev/benchmarks/macrobenchmarks/test_driver/stack_size_perf_test.dart

@@ -1,38 +0,0 @@
-// Copyright 2014 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 'dart:convert' show JsonEncoder;
-
-import 'package:file/file.dart';
-import 'package:flutter_driver/flutter_driver.dart';
-import 'package:macrobenchmarks/common.dart';
-import 'package:path/path.dart' as path;
-import 'package:test/test.dart' hide TypeMatcher, isInstanceOf;
-
-import 'util.dart';
-
-const JsonEncoder _prettyEncoder = JsonEncoder.withIndent('  ');
-
-void main() {
-  test('stack_size', () async {
-    late int stackSizeInBytes;
-    await runDriverTestForRoute(kStackSizeRouteName, (FlutterDriver driver) async {
-      final String stackSize = await driver.getText(find.byValueKey(kStackSizeKey));
-      expect(stackSize.isNotEmpty, isTrue);
-      stackSizeInBytes = int.parse(stackSize);
-    });
-
-    expect(stackSizeInBytes > 0, isTrue);
-
-    await fs.directory(testOutputsDirectory).create(recursive: true);
-    final File file = fs.file(path.join(testOutputsDirectory, 'stack_size.json'));
-    await file.writeAsString(_encodeJson(<String, dynamic>{
-      'stack_size': stackSizeInBytes,
-    }));
-  }, timeout: Timeout.none);
-}
-
-String _encodeJson(Map<String, dynamic> jsonObject) {
-  return _prettyEncoder.convert(jsonObject);
-}

dev/devicelab/bin/tasks/android_stack_size_test.dart

@@ -1,12 +0,0 @@
-// Copyright 2014 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 'package:flutter_devicelab/framework/devices.dart';
-import 'package:flutter_devicelab/framework/framework.dart';
-import 'package:flutter_devicelab/tasks/perf_tests.dart';
-
-Future<void> main() async {
-  deviceOperatingSystem = DeviceOperatingSystem.androidArm;
-  await task(createStackSizeTest());
-}

dev/devicelab/lib/tasks/perf_tests.dart

@@ -353,43 +353,6 @@ TaskFunction createSlidersPerfTest() {
   ).run;
 }
 
-TaskFunction createStackSizeTest() {
-  final String testDirectory =
-      '${flutterDirectory.path}/dev/benchmarks/macrobenchmarks';
-  const String testTarget = 'test_driver/run_app.dart';
-  const String testDriver = 'test_driver/stack_size_perf_test.dart';
-  return () {
-    return inDirectory<TaskResult>(testDirectory, () async {
-      final Device device = await devices.workingDevice;
-      await device.unlock();
-      final String deviceId = device.deviceId;
-      await flutter('packages', options: <String>['get']);
-
-      await flutter('drive', options: <String>[
-        '--no-android-gradle-daemon',
-        '-v',
-        '--verbose-system-logs',
-        '--profile',
-        '-t', testTarget,
-        '--driver', testDriver,
-        '-d',
-        deviceId,
-      ]);
-      final Map<String, dynamic> data = json.decode(
-        file('${_testOutputDirectory(testDirectory)}/stack_size.json').readAsStringSync(),
-      ) as Map<String, dynamic>;
-
-      final Map<String, dynamic> result = <String, dynamic>{
-        'stack_size_per_nesting_level': data['stack_size'],
-      };
-      return TaskResult.success(
-        result,
-        benchmarkScoreKeys: result.keys.toList(),
-      );
-    });
-  };
-}
-
 TaskFunction createFullscreenTextfieldPerfTest() {
   return PerfTest(
     '${flutterDirectory.path}/dev/benchmarks/macrobenchmarks',