[benchmarks] Add benchmark for taking tear-offs repeatedly

Issue: #54808
Change-Id: Ice28033bab71e30f9a586564d7e55d9c4f5ce770
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/350640
Reviewed-by: Martin Kustermann <[email protected]>
Commit-Queue: Alexander Markov <[email protected]>

benchmarks/TearOff/dart/TearOff.dart

@@ -0,0 +1,192 @@
+// Copyright (c) 2024, the Dart project authors.  Please see the AUTHORS file
+// 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 'package:benchmark_harness/benchmark_harness.dart';
+
+// Micro-benchmark for taking tear-off of instance method multiple
+// times and in a loop.
+
+class BenchTearOffInlined extends BenchmarkBase {
+  BenchTearOffInlined() : super('TearOff.Inlined');
+
+  int sum = 0;
+
+  @pragma('vm:prefer-inline')
+  @pragma('dart2js:prefer-inline')
+  void foo(int arg) {
+    sum += arg;
+  }
+
+  @pragma('vm:prefer-inline')
+  @pragma('dart2js:prefer-inline')
+  void callIt(void Function(int) func, int arg) {
+    func(arg);
+  }
+
+  @override
+  @pragma('vm:never-inline')
+  @pragma('dart2js:never-inline')
+  void run() {
+    sum = 0;
+    callIt(foo, 1);
+    callIt(foo, 2);
+    callIt(foo, 3);
+    callIt(foo, 4);
+    callIt(foo, 5);
+    for (int i = 11; i < 20; ++i) {
+      callIt(foo, i);
+    }
+    callIt(foo, 6);
+    callIt(foo, 7);
+    callIt(foo, 8);
+    callIt(foo, 9);
+    callIt(foo, 10);
+
+    const int expectedSum = 20 * (20 - 1) ~/ 2;
+    if (sum != expectedSum) throw 'Bad result: $sum';
+  }
+}
+
+class BenchTearOffInlinedInTry extends BenchmarkBase {
+  BenchTearOffInlinedInTry() : super('TearOff.Inlined.InTry');
+
+  int sum = 0;
+
+  @pragma('vm:prefer-inline')
+  @pragma('dart2js:prefer-inline')
+  void foo(int arg) {
+    sum += arg;
+  }
+
+  @pragma('vm:prefer-inline')
+  @pragma('dart2js:prefer-inline')
+  void callIt(void Function(int) func, int arg) {
+    func(arg);
+  }
+
+  @override
+  @pragma('vm:never-inline')
+  @pragma('dart2js:never-inline')
+  void run() {
+    sum = 0;
+    try {
+      callIt(foo, 1);
+      callIt(foo, 2);
+      callIt(foo, 3);
+      callIt(foo, 4);
+      callIt(foo, 5);
+      for (int i = 11; i < 20; ++i) {
+        callIt(foo, i);
+      }
+      callIt(foo, 6);
+      callIt(foo, 7);
+      callIt(foo, 8);
+      callIt(foo, 9);
+      callIt(foo, 10);
+    } finally {
+      const int expectedSum = 20 * (20 - 1) ~/ 2;
+      if (sum != expectedSum) throw 'Bad result: $sum';
+    }
+  }
+}
+
+class BenchTearOffNotInlined extends BenchmarkBase {
+  BenchTearOffNotInlined() : super('TearOff.NotInlined');
+
+  int sum = 0;
+
+  @pragma('vm:never-inline')
+  @pragma('dart2js:never-inline')
+  void foo(int arg) {
+    sum += arg;
+  }
+
+  @pragma('vm:never-inline')
+  @pragma('dart2js:never-inline')
+  void callIt(void Function(int) func, int arg) {
+    func(arg);
+  }
+
+  @override
+  @pragma('vm:never-inline')
+  @pragma('dart2js:never-inline')
+  void run() {
+    sum = 0;
+    callIt(foo, 1);
+    callIt(foo, 2);
+    callIt(foo, 3);
+    callIt(foo, 4);
+    callIt(foo, 5);
+    for (int i = 11; i < 20; ++i) {
+      callIt(foo, i);
+    }
+    callIt(foo, 6);
+    callIt(foo, 7);
+    callIt(foo, 8);
+    callIt(foo, 9);
+    callIt(foo, 10);
+
+    const int expectedSum = 20 * (20 - 1) ~/ 2;
+    if (sum != expectedSum) throw 'Bad result: $sum';
+  }
+}
+
+class BenchTearOffNotInlinedInTry extends BenchmarkBase {
+  BenchTearOffNotInlinedInTry() : super('TearOff.NotInlined.InTry');
+
+  int sum = 0;
+
+  @pragma('vm:never-inline')
+  @pragma('dart2js:never-inline')
+  void foo(int arg) {
+    sum += arg;
+  }
+
+  @pragma('vm:never-inline')
+  @pragma('dart2js:never-inline')
+  void callIt(void Function(int) func, int arg) {
+    func(arg);
+  }
+
+  @override
+  @pragma('vm:never-inline')
+  @pragma('dart2js:never-inline')
+  void run() {
+    sum = 0;
+    try {
+      callIt(foo, 1);
+      callIt(foo, 2);
+      callIt(foo, 3);
+      callIt(foo, 4);
+      callIt(foo, 5);
+      for (int i = 11; i < 20; ++i) {
+        callIt(foo, i);
+      }
+      callIt(foo, 6);
+      callIt(foo, 7);
+      callIt(foo, 8);
+      callIt(foo, 9);
+      callIt(foo, 10);
+    } finally {
+      const int expectedSum = 20 * (20 - 1) ~/ 2;
+      if (sum != expectedSum) throw 'Bad result: $sum';
+    }
+  }
+}
+
+void main() {
+  final benchmarks = [
+    BenchTearOffInlined(),
+    BenchTearOffInlinedInTry(),
+    BenchTearOffNotInlined(),
+    BenchTearOffNotInlinedInTry(),
+  ];
+
+  for (final benchmark in benchmarks) {
+    benchmark.warmup();
+  }
+  for (final benchmark in benchmarks) {
+    benchmark.report();
+  }
+}