Add dexoptanalyzer tool

dexoptanalyzer is a command line tool which analyzes whether or not a
given dex file needs to be dexopted. It is a wrapper around
OatFileAssistant::GetDexOptNeeded and its results have a mapping to
OatFileAssistant::DexOptNeeded.

This is needed for the management of secondary dex file. We need a way
to retrieve the DexOptNeeded status from installd outside system server.
We can't simply use the system server path (as we do for the main apks)
because system server can't access content writable by the apps.

Bug: 32871170
Test: m test-art-(host|target)
Change-Id: Ife1534560ca2658079d4a38a30bc8d94f35fe9c8
diff --git a/dexoptanalyzer/dexoptanalyzer.cc b/dexoptanalyzer/dexoptanalyzer.cc
new file mode 100644
index 0000000..965e407
--- /dev/null
+++ b/dexoptanalyzer/dexoptanalyzer.cc
@@ -0,0 +1,265 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <string>
+
+#include "android-base/stringprintf.h"
+#include "android-base/strings.h"
+#include "compiler_filter.h"
+#include "dex_file.h"
+#include "noop_compiler_callbacks.h"
+#include "oat_file_assistant.h"
+#include "os.h"
+#include "runtime.h"
+#include "thread-inl.h"
+#include "utils.h"
+
+namespace art {
+
+// See OatFileAssistant docs for the meaning of the valid return codes.
+enum ReturnCodes {
+  kNoDexOptNeeded = 0,
+  kDex2OatFromScratch = 1,
+  kDex2OatForBootImageOat = 2,
+  kDex2OatForFilterOat = 3,
+  kDex2OatForRelocationOat = 4,
+  kDex2OatForBootImageOdex = 5,
+  kDex2OatForFilterOdex = 6,
+  kDex2OatForRelocationOdex = 7,
+
+  kErrorInvalidArguments = 101,
+  kErrorCannotCreateRuntime = 102,
+  kErrorUnknownDexOptNeeded = 103
+};
+
+static int original_argc;
+static char** original_argv;
+
+static std::string CommandLine() {
+  std::vector<std::string> command;
+  for (int i = 0; i < original_argc; ++i) {
+    command.push_back(original_argv[i]);
+  }
+  return android::base::Join(command, ' ');
+}
+
+static void UsageErrorV(const char* fmt, va_list ap) {
+  std::string error;
+  android::base::StringAppendV(&error, fmt, ap);
+  LOG(ERROR) << error;
+}
+
+static void UsageError(const char* fmt, ...) {
+  va_list ap;
+  va_start(ap, fmt);
+  UsageErrorV(fmt, ap);
+  va_end(ap);
+}
+
+NO_RETURN static void Usage(const char *fmt, ...) {
+  va_list ap;
+  va_start(ap, fmt);
+  UsageErrorV(fmt, ap);
+  va_end(ap);
+
+  UsageError("Command: %s", CommandLine().c_str());
+  UsageError("  Performs a dexopt analysis on the given dex file and returns whether or not");
+  UsageError("  the dex file needs to be dexopted.");
+  UsageError("Usage: dexoptanalyzer [options]...");
+  UsageError("");
+  UsageError("  --dex-file=<filename>: the dex file which should be analyzed.");
+  UsageError("");
+  UsageError("  --isa=<string>: the instruction set for which the analysis should be performed.");
+  UsageError("");
+  UsageError("  --compiler-filter=<string>: the target compiler filter to be used as reference");
+  UsageError("       when deciding if the dex file needs to be optimized.");
+  UsageError("");
+  UsageError("  --assume-profile-changed: assumes the profile information has changed");
+  UsageError("       when deciding if the dex file needs to be optimized.");
+  UsageError("");
+  UsageError("  --image=<filename>: optional, the image to be used to decide if the associated");
+  UsageError("       oat file is up to date. Defaults to $ANDROID_ROOT/framework/boot.art.");
+  UsageError("       Example: --image=/system/framework/boot.art");
+  UsageError("");
+  UsageError("  --android-data=<directory>: optional, the directory which should be used as");
+  UsageError("       android-data. By default ANDROID_DATA env variable is used.");
+  UsageError("");
+  UsageError("Return code:");
+  UsageError("  To make it easier to integrate with the internal tools this command will make");
+  UsageError("    available its result (dexoptNeeded) as the exit/return code. i.e. it will not");
+  UsageError("    return 0 for success and a non zero values for errors as the conventional");
+  UsageError("    commands. The following return codes are possible:");
+  UsageError("        kNoDexOptNeeded = 0");
+  UsageError("        kDex2OatFromScratch = 1");
+  UsageError("        kDex2OatForBootImageOat = 2");
+  UsageError("        kDex2OatForFilterOat = 3");
+  UsageError("        kDex2OatForRelocationOat = 4");
+  UsageError("        kDex2OatForBootImageOdex = 5");
+  UsageError("        kDex2OatForFilterOdex = 6");
+  UsageError("        kDex2OatForRelocationOdex = 7");
+
+  UsageError("        kErrorInvalidArguments = 101");
+  UsageError("        kErrorCannotCreateRuntime = 102");
+  UsageError("        kErrorUnknownDexOptNeeded = 103");
+  UsageError("");
+
+  exit(kErrorInvalidArguments);
+}
+
+class DexoptAnalyzer FINAL {
+ public:
+  DexoptAnalyzer() : assume_profile_changed_(false) {}
+
+  void ParseArgs(int argc, char **argv) {
+    original_argc = argc;
+    original_argv = argv;
+
+    InitLogging(argv, Runtime::Aborter);
+    // Skip over the command name.
+    argv++;
+    argc--;
+
+    if (argc == 0) {
+      Usage("No arguments specified");
+    }
+
+    for (int i = 0; i < argc; ++i) {
+      const StringPiece option(argv[i]);
+      if (option == "--assume-profile-changed") {
+        assume_profile_changed_ = true;
+      } else if (option.starts_with("--dex-file=")) {
+        dex_file_ = option.substr(strlen("--dex-file=")).ToString();
+      } else if (option.starts_with("--compiler-filter=")) {
+        std::string filter_str = option.substr(strlen("--compiler-filter=")).ToString();
+        if (!CompilerFilter::ParseCompilerFilter(filter_str.c_str(), &compiler_filter_)) {
+          Usage("Invalid compiler filter '%s'", option.data());
+        }
+      } else if (option.starts_with("--isa=")) {
+        std::string isa_str = option.substr(strlen("--isa=")).ToString();
+        isa_ = GetInstructionSetFromString(isa_str.c_str());
+        if (isa_ == kNone) {
+          Usage("Invalid isa '%s'", option.data());
+        }
+      } else if (option.starts_with("--image=")) {
+        image_ = option.substr(strlen("--image=")).ToString();
+      } else if (option.starts_with("--android-data=")) {
+        // Overwrite android-data if needed (oat file assistant relies on a valid directory to
+        // compute dalvik-cache folder). This is mostly used in tests.
+        std::string new_android_data = option.substr(strlen("--android-data=")).ToString();
+        setenv("ANDROID_DATA", new_android_data.c_str(), 1);
+      } else {
+        Usage("Unknown argument '%s'", option.data());
+      }
+    }
+
+    if (image_.empty()) {
+      // If we don't receive the image, try to use the default one.
+      // Tests may specify a different image (e.g. core image).
+      std::string error_msg;
+      image_ = GetDefaultBootImageLocation(&error_msg);
+
+      if (image_.empty()) {
+        LOG(ERROR) << error_msg;
+        Usage("--image unspecified and ANDROID_ROOT not set or image file does not exist.");
+      }
+    }
+  }
+
+  bool CreateRuntime() {
+    RuntimeOptions options;
+    // The image could be custom, so make sure we explicitly pass it.
+    std::string img = "-Ximage:" + image_;
+    options.push_back(std::make_pair(img.c_str(), nullptr));
+    // The instruction set of the image should match the instruction set we will test.
+    const void* isa_opt = reinterpret_cast<const void*>(GetInstructionSetString(isa_));
+    options.push_back(std::make_pair("imageinstructionset", isa_opt));
+     // Disable libsigchain. We don't don't need it to evaluate DexOptNeeded status.
+    options.push_back(std::make_pair("-Xno-sig-chain", nullptr));
+    // Pretend we are a compiler so that we can re-use the same infrastructure to load a different
+    // ISA image and minimize the amount of things that get started.
+    NoopCompilerCallbacks callbacks;
+    options.push_back(std::make_pair("compilercallbacks", &callbacks));
+    // Make sure we don't attempt to relocate. The tool should only retrieve the DexOptNeeded
+    // status and not attempt to relocate the boot image.
+    options.push_back(std::make_pair("-Xnorelocate", nullptr));
+
+    if (!Runtime::Create(options, false)) {
+      LOG(ERROR) << "Unable to initialize runtime";
+      return false;
+    }
+    // Runtime::Create acquired the mutator_lock_ that is normally given away when we
+    // Runtime::Start. Give it away now.
+    Thread::Current()->TransitionFromRunnableToSuspended(kNative);
+
+    return true;
+  }
+
+  int GetDexOptNeeded() {
+    // If the file does not exist there's nothing to do.
+    // This is a fast path to avoid creating the runtime (b/34385298).
+    if (!OS::FileExists(dex_file_.c_str())) {
+      return kNoDexOptNeeded;
+    }
+    if (!CreateRuntime()) {
+      return kErrorCannotCreateRuntime;
+    }
+    OatFileAssistant oat_file_assistant(dex_file_.c_str(), isa_, /*load_executable*/ false);
+    // Always treat elements of the bootclasspath as up-to-date.
+    // TODO(calin): this check should be in OatFileAssistant.
+    if (oat_file_assistant.IsInBootClassPath()) {
+      return kNoDexOptNeeded;
+    }
+    int dexoptNeeded = oat_file_assistant.GetDexOptNeeded(
+        compiler_filter_, assume_profile_changed_);
+
+    // Convert OatFileAssitant codes to dexoptanalyzer codes.
+    switch (dexoptNeeded) {
+      case OatFileAssistant::kNoDexOptNeeded: return kNoDexOptNeeded;
+      case OatFileAssistant::kDex2OatFromScratch: return kDex2OatFromScratch;
+      case OatFileAssistant::kDex2OatForBootImage: return kDex2OatForBootImageOat;
+      case OatFileAssistant::kDex2OatForFilter: return kDex2OatForFilterOat;
+      case OatFileAssistant::kDex2OatForRelocation: return kDex2OatForRelocationOat;
+
+      case -OatFileAssistant::kDex2OatForBootImage: return kDex2OatForBootImageOdex;
+      case -OatFileAssistant::kDex2OatForFilter: return kDex2OatForFilterOdex;
+      case -OatFileAssistant::kDex2OatForRelocation: return kDex2OatForRelocationOdex;
+      default:
+        LOG(ERROR) << "Unknown dexoptNeeded " << dexoptNeeded;
+        return kErrorUnknownDexOptNeeded;
+    }
+  }
+
+ private:
+  std::string dex_file_;
+  InstructionSet isa_;
+  CompilerFilter::Filter compiler_filter_;
+  bool assume_profile_changed_;
+  std::string image_;
+};
+
+static int dexoptAnalyze(int argc, char** argv) {
+  DexoptAnalyzer analyzer;
+
+  // Parse arguments. Argument mistakes will lead to exit(kErrorInvalidArguments) in UsageError.
+  analyzer.ParseArgs(argc, argv);
+  return analyzer.GetDexOptNeeded();
+}
+
+}  // namespace art
+
+int main(int argc, char **argv) {
+  return art::dexoptAnalyze(argc, argv);
+}