Add ./tools/test.py -c precompiler -r dart_precompiled.

tools/precompilation/precompiler.dart

+// Copyright (c) 2015, 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.
+
+library precompiler;
+
+import 'dart:io';
+
+void run(String executable, String arguments, [String workingDirectory]) {
+  print("+ $executable ${arguments.join(' ')}");
+  var result = Process.runSync(executable, arguments,
+                               workingDirectory: workingDirectory);
+  stdout.write(result.stdout);
+  stderr.write(result.stderr);
+  if (result.exitCode != 0) {
+    exit(result.exitCode);
+  }
+}
+
+void main(List<String> args) {
+  var configuration = Platform.environment["DART_CONFIGURATION"];
+
+  var cc, cc_flags, shared, libname;
+  if (Platform.isLinux) {
+    cc = 'gcc';
+    shared = '-shared';
+    libname = 'libprecompiled.so';
+  } else if (Platform.isMacOS) {
+    cc = 'clang';
+    shared = '-dynamiclib';
+    libname = 'libprecompiled.dylib';
+  } else {
+    print("Test only supports Linux and Mac");
+    return;
+  }
+
+  if (configuration.endsWith("X64")) {
+    cc_flags = "-m64";
+  } else if (configuration.endsWith("SIMARM64")) {
+    cc_flags = "-m64";
+  } else if (configuration.endsWith("SIMARM")) {
+    cc_flags = "-m32";
+  } else if (configuration.endsWith("SIMMIPS")) {
+    cc_flags = "-m32";
+  } else if (configuration.endsWith("ARM")) {
+    cc_flags = "";
+  } else if (configuration.endsWith("MIPS")) {
+    cc_flags = "-EL";
+  } else {
+    print("Architecture not supported: $configuration");
+    return;
+  }
+
+  var tmpDir;
+  for (var arg in args) {
+    if (arg.startsWith("--gen-precompiled-snapshot")) {
+      tmpDir = arg.substring("--gen-precompiled-snapshot".length + 1);
+    }
+  }
+  print("Using directory $tmpDir");
+
+  run(args[0], args.sublist(1));
+  run(cc, [shared, cc_flags, "-o", libname, "precompiled.S"], tmpDir);
+}