[test] Add option to test harness to run VM tests under rr and save traces from crashes.

E.g., ./tools/test.py --rr --repeat=100

Change-Id: I2776b38daa6b14d1ca59800969a0ecfaeb71a0ee
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/167241
Commit-Queue: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>

pkg/test_runner/lib/src/command.dart

@@ -10,6 +10,7 @@ import 'dart:io' as io;
 import 'command_output.dart';
 import 'configuration.dart';
 import 'path.dart';
+import 'test_case.dart';
 import 'utils.dart';
 
 /// A command executed as a step in a test case.
@@ -531,6 +532,75 @@ class VMBatchCommand extends ProcessCommand implements VMCommand {
   }
 }
 
+// Run a VM test under RR, and copy the trace if it crashes. Using a helper
+// script like the precompiler does not work because the RR traces are large
+// and we must diligently erase them for non-crashes even if the test times
+// out and would be killed by the harness, so the copying and cleanup logic
+// must be in the harness.
+class RRCommand extends Command {
+  VMCommand originalCommand;
+  VMCommand wrappedCommand;
+  io.Directory recordingDir;
+  io.Directory savedDir;
+
+  RRCommand(this.originalCommand)
+      : super._("rr", index: originalCommand.index) {
+    final suffix = "/rr-trace-" + originalCommand.hashCode.toString();
+    recordingDir = io.Directory(io.Directory.systemTemp.path + suffix);
+    savedDir = io.Directory("out" + suffix);
+    final executable = "rr";
+    final arguments = <String>[
+      "record",
+      "--chaos",
+      "--output-trace-dir=" + recordingDir.path,
+    ];
+    arguments.add(originalCommand.executable);
+    arguments.addAll(originalCommand.arguments);
+    wrappedCommand = VMCommand(
+        executable, arguments, originalCommand.environmentOverrides,
+        index: originalCommand.index);
+  }
+
+  RRCommand indexedCopy(int index) =>
+      RRCommand(originalCommand.indexedCopy(index));
+
+  Future<CommandOutput> run(int timeout) async {
+    // rr will fail if the output trace directory already exists. Delete any
+    // that might be leftover from interrupting the harness.
+    if (await recordingDir.exists()) {
+      await recordingDir.delete(recursive: true);
+    }
+    final output = await RunningProcess(wrappedCommand, timeout).run();
+    if (output.hasCrashed) {
+      if (await savedDir.exists()) {
+        await savedDir.delete(recursive: true);
+      }
+      await recordingDir.rename(savedDir.path);
+      await io.File(savedDir.path + "/command.txt")
+          .writeAsString(wrappedCommand.reproductionCommand);
+      await io.File(savedDir.path + "/stdout.txt").writeAsBytes(output.stdout);
+      await io.File(savedDir.path + "/stderr.txt").writeAsBytes(output.stderr);
+    } else {
+      await recordingDir.delete(recursive: true);
+    }
+
+    return VMCommandOutput(this, output.exitCode, output.hasTimedOut,
+        output.stdout, output.stderr, output.time, output.pid);
+  }
+
+  String get reproductionCommand =>
+      wrappedCommand.reproductionCommand + " (rr replay " + savedDir.path + ")";
+
+  void _buildHashCode(HashCodeBuilder builder) {
+    originalCommand._buildHashCode(builder);
+    builder.add(42);
+  }
+
+  bool _equal(RRCommand other) =>
+      hashCode == other.hashCode &&
+      originalCommand._equal(other.originalCommand);
+}
+
 abstract class AdbCommand {
   String get buildPath;
   List<String> get extraLibraries;

pkg/test_runner/lib/src/configuration.dart

@@ -32,6 +32,7 @@ class TestConfiguration {
       this.batch,
       this.batchDart2JS,
       this.copyCoreDumps,
+      this.rr,
       this.isVerbose,
       this.listTests,
       this.listStatusFiles,
@@ -82,6 +83,7 @@ class TestConfiguration {
   final bool batch;
   final bool batchDart2JS;
   final bool copyCoreDumps;
+  final bool rr;
   final bool fastTestsOnly;
   final bool isVerbose;
   final bool listTests;

pkg/test_runner/lib/src/options.dart

@@ -293,6 +293,8 @@ settings.''',
         '''If we see a crash that we did not expect, copy the core dumps to
 "/tmp".''',
         hide: true),
+    _Option.bool('rr', '''Run VM tests under rr and save traces from crashes''',
+        hide: true),
     _Option(
         'local_ip',
         '''IP address the HTTP servers should listen on. This address is also
@@ -735,6 +737,7 @@ compiler.''',
           batch: !(data["noBatch"] as bool),
           batchDart2JS: data["dart2js_batch"] as bool,
           copyCoreDumps: data["copy_coredumps"] as bool,
+          rr: data["rr"] as bool,
           isVerbose: data["verbose"] as bool,
           listTests: data["list"] as bool,
           listStatusFiles: data["list_status_files"] as bool,

pkg/test_runner/lib/src/process_queue.dart

@@ -614,6 +614,8 @@ class CommandExecutorImpl implements CommandExecutor {
       return RunningProcess(command, timeout,
               configuration: globalConfiguration)
           .run();
+    } else if (command is RRCommand) {
+      return command.run(timeout);
     } else {
       throw ArgumentError("Unknown command type ${command.runtimeType}.");
     }

pkg/test_runner/lib/src/runtime_configuration.dart

@@ -263,6 +263,9 @@ class DartVmRuntimeConfiguration extends RuntimeConfiguration {
     if (_configuration.sanitizer != Sanitizer.none) {
       multiplier *= 2;
     }
+    if (_configuration.rr) {
+      multiplier *= 2;
+    }
     return multiplier;
   }
 }
@@ -297,7 +300,11 @@ class StandaloneDartRuntimeConfiguration extends DartVmRuntimeConfiguration {
       arguments.insertAll(0, config.arguments);
       executable = config.executable;
     }
-    return [VMCommand(executable, arguments, environmentOverrides)];
+    var command = VMCommand(executable, arguments, environmentOverrides);
+    if (_configuration.rr && !isCrashExpected) {
+      return [RRCommand(command)];
+    }
+    return [command];
   }
 }
 
@@ -326,7 +333,11 @@ class DartPrecompiledRuntimeConfiguration extends DartVmRuntimeConfiguration {
       executable = config.executable;
     }
 
-    return [VMCommand(executable, arguments, environmentOverrides)];
+    var command = VMCommand(executable, arguments, environmentOverrides);
+    if (_configuration.rr && !isCrashExpected) {
+      return [RRCommand(command)];
+    }
+    return [command];
   }
 }