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      1 /*
      2  * Copyright (C) 2011 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 #include "runtime.h"
     18 
     19 // sys/mount.h has to come before linux/fs.h due to redefinition of MS_RDONLY, MS_BIND, etc
     20 #include <sys/mount.h>
     21 #include <linux/fs.h>
     22 
     23 #include <signal.h>
     24 #include <sys/syscall.h>
     25 
     26 #include <cstdio>
     27 #include <cstdlib>
     28 #include <limits>
     29 #include <vector>
     30 
     31 #include "arch/arm/registers_arm.h"
     32 #include "arch/mips/registers_mips.h"
     33 #include "arch/x86/registers_x86.h"
     34 #include "atomic.h"
     35 #include "class_linker.h"
     36 #include "debugger.h"
     37 #include "gc/accounting/card_table-inl.h"
     38 #include "gc/heap.h"
     39 #include "gc/space/space.h"
     40 #include "image.h"
     41 #include "instrumentation.h"
     42 #include "intern_table.h"
     43 #include "invoke_arg_array_builder.h"
     44 #include "jni_internal.h"
     45 #include "mirror/art_field-inl.h"
     46 #include "mirror/art_method-inl.h"
     47 #include "mirror/array.h"
     48 #include "mirror/class-inl.h"
     49 #include "mirror/class_loader.h"
     50 #include "mirror/throwable.h"
     51 #include "monitor.h"
     52 #include "oat_file.h"
     53 #include "ScopedLocalRef.h"
     54 #include "scoped_thread_state_change.h"
     55 #include "signal_catcher.h"
     56 #include "signal_set.h"
     57 #include "sirt_ref.h"
     58 #include "thread.h"
     59 #include "thread_list.h"
     60 #include "trace.h"
     61 #include "UniquePtr.h"
     62 #include "verifier/method_verifier.h"
     63 #include "well_known_classes.h"
     64 
     65 #include "JniConstants.h"  // Last to avoid LOG redefinition in ics-mr1-plus-art.
     66 
     67 namespace art {
     68 
     69 Runtime* Runtime::instance_ = NULL;
     70 
     71 Runtime::Runtime()
     72     : is_compiler_(false),
     73       is_zygote_(false),
     74       is_concurrent_gc_enabled_(true),
     75       is_explicit_gc_disabled_(false),
     76       default_stack_size_(0),
     77       heap_(NULL),
     78       monitor_list_(NULL),
     79       thread_list_(NULL),
     80       intern_table_(NULL),
     81       class_linker_(NULL),
     82       signal_catcher_(NULL),
     83       java_vm_(NULL),
     84       pre_allocated_OutOfMemoryError_(NULL),
     85       resolution_method_(NULL),
     86       threads_being_born_(0),
     87       shutdown_cond_(new ConditionVariable("Runtime shutdown", *Locks::runtime_shutdown_lock_)),
     88       shutting_down_(false),
     89       shutting_down_started_(false),
     90       started_(false),
     91       finished_starting_(false),
     92       vfprintf_(NULL),
     93       exit_(NULL),
     94       abort_(NULL),
     95       stats_enabled_(false),
     96       method_trace_(0),
     97       method_trace_file_size_(0),
     98       instrumentation_(),
     99       use_compile_time_class_path_(false),
    100       main_thread_group_(NULL),
    101       system_thread_group_(NULL),
    102       system_class_loader_(NULL) {
    103   for (int i = 0; i < Runtime::kLastCalleeSaveType; i++) {
    104     callee_save_methods_[i] = NULL;
    105   }
    106 }
    107 
    108 Runtime::~Runtime() {
    109   Thread* self = Thread::Current();
    110   {
    111     MutexLock mu(self, *Locks::runtime_shutdown_lock_);
    112     shutting_down_started_ = true;
    113     while (threads_being_born_ > 0) {
    114       shutdown_cond_->Wait(self);
    115     }
    116     shutting_down_ = true;
    117   }
    118   Trace::Shutdown();
    119 
    120   // Make sure to let the GC complete if it is running.
    121   heap_->WaitForConcurrentGcToComplete(self);
    122   heap_->DeleteThreadPool();
    123 
    124   // Make sure our internal threads are dead before we start tearing down things they're using.
    125   Dbg::StopJdwp();
    126   delete signal_catcher_;
    127 
    128   // Make sure all other non-daemon threads have terminated, and all daemon threads are suspended.
    129   delete thread_list_;
    130   delete monitor_list_;
    131   delete class_linker_;
    132   delete heap_;
    133   delete intern_table_;
    134   delete java_vm_;
    135   Thread::Shutdown();
    136   QuasiAtomic::Shutdown();
    137   verifier::MethodVerifier::Shutdown();
    138   // TODO: acquire a static mutex on Runtime to avoid racing.
    139   CHECK(instance_ == NULL || instance_ == this);
    140   instance_ = NULL;
    141 }
    142 
    143 struct AbortState {
    144   void Dump(std::ostream& os) {
    145     if (gAborting > 1) {
    146       os << "Runtime aborting --- recursively, so no thread-specific detail!\n";
    147       return;
    148     }
    149     gAborting++;
    150     os << "Runtime aborting...\n";
    151     if (Runtime::Current() == NULL) {
    152       os << "(Runtime does not yet exist!)\n";
    153       return;
    154     }
    155     Thread* self = Thread::Current();
    156     if (self == NULL) {
    157       os << "(Aborting thread was not attached to runtime!)\n";
    158     } else {
    159       // TODO: we're aborting and the ScopedObjectAccess may attempt to acquire the mutator_lock_
    160       //       which may block indefinitely if there's a misbehaving thread holding it exclusively.
    161       //       The code below should be made robust to this.
    162       ScopedObjectAccess soa(self);
    163       os << "Aborting thread:\n";
    164       self->Dump(os);
    165       if (self->IsExceptionPending()) {
    166         ThrowLocation throw_location;
    167         mirror::Throwable* exception = self->GetException(&throw_location);
    168         os << "Pending exception " << PrettyTypeOf(exception)
    169             << " thrown by '" << throw_location.Dump() << "'\n"
    170             << exception->Dump();
    171       }
    172     }
    173     DumpAllThreads(os, self);
    174   }
    175 
    176   void DumpAllThreads(std::ostream& os, Thread* self) NO_THREAD_SAFETY_ANALYSIS {
    177     bool tll_already_held = Locks::thread_list_lock_->IsExclusiveHeld(self);
    178     bool ml_already_held = Locks::mutator_lock_->IsSharedHeld(self);
    179     if (!tll_already_held || !ml_already_held) {
    180       os << "Dumping all threads without appropriate locks held:"
    181           << (!tll_already_held ? " thread list lock" : "")
    182           << (!ml_already_held ? " mutator lock" : "")
    183           << "\n";
    184     }
    185     os << "All threads:\n";
    186     Runtime::Current()->GetThreadList()->DumpLocked(os);
    187   }
    188 };
    189 
    190 void Runtime::Abort() {
    191   gAborting++;  // set before taking any locks
    192 
    193   // Ensure that we don't have multiple threads trying to abort at once,
    194   // which would result in significantly worse diagnostics.
    195   MutexLock mu(Thread::Current(), *Locks::abort_lock_);
    196 
    197   // Get any pending output out of the way.
    198   fflush(NULL);
    199 
    200   // Many people have difficulty distinguish aborts from crashes,
    201   // so be explicit.
    202   AbortState state;
    203   LOG(INTERNAL_FATAL) << Dumpable<AbortState>(state);
    204 
    205   // Call the abort hook if we have one.
    206   if (Runtime::Current() != NULL && Runtime::Current()->abort_ != NULL) {
    207     LOG(INTERNAL_FATAL) << "Calling abort hook...";
    208     Runtime::Current()->abort_();
    209     // notreached
    210     LOG(INTERNAL_FATAL) << "Unexpectedly returned from abort hook!";
    211   }
    212 
    213 #if defined(__GLIBC__)
    214   // TODO: we ought to be able to use pthread_kill(3) here (or abort(3),
    215   // which POSIX defines in terms of raise(3), which POSIX defines in terms
    216   // of pthread_kill(3)). On Linux, though, libcorkscrew can't unwind through
    217   // libpthread, which means the stacks we dump would be useless. Calling
    218   // tgkill(2) directly avoids that.
    219   syscall(__NR_tgkill, getpid(), GetTid(), SIGABRT);
    220   // TODO: LLVM installs it's own SIGABRT handler so exit to be safe... Can we disable that in LLVM?
    221   // If not, we could use sigaction(3) before calling tgkill(2) and lose this call to exit(3).
    222   exit(1);
    223 #else
    224   abort();
    225 #endif
    226   // notreached
    227 }
    228 
    229 bool Runtime::PreZygoteFork() {
    230   heap_->PreZygoteFork();
    231   return true;
    232 }
    233 
    234 void Runtime::CallExitHook(jint status) {
    235   if (exit_ != NULL) {
    236     ScopedThreadStateChange tsc(Thread::Current(), kNative);
    237     exit_(status);
    238     LOG(WARNING) << "Exit hook returned instead of exiting!";
    239   }
    240 }
    241 
    242 // Parse a string of the form /[0-9]+[kKmMgG]?/, which is used to specify
    243 // memory sizes.  [kK] indicates kilobytes, [mM] megabytes, and
    244 // [gG] gigabytes.
    245 //
    246 // "s" should point just past the "-Xm?" part of the string.
    247 // "div" specifies a divisor, e.g. 1024 if the value must be a multiple
    248 // of 1024.
    249 //
    250 // The spec says the -Xmx and -Xms options must be multiples of 1024.  It
    251 // doesn't say anything about -Xss.
    252 //
    253 // Returns 0 (a useless size) if "s" is malformed or specifies a low or
    254 // non-evenly-divisible value.
    255 //
    256 size_t ParseMemoryOption(const char* s, size_t div) {
    257   // strtoul accepts a leading [+-], which we don't want,
    258   // so make sure our string starts with a decimal digit.
    259   if (isdigit(*s)) {
    260     char* s2;
    261     size_t val = strtoul(s, &s2, 10);
    262     if (s2 != s) {
    263       // s2 should be pointing just after the number.
    264       // If this is the end of the string, the user
    265       // has specified a number of bytes.  Otherwise,
    266       // there should be exactly one more character
    267       // that specifies a multiplier.
    268       if (*s2 != '\0') {
    269         // The remainder of the string is either a single multiplier
    270         // character, or nothing to indicate that the value is in
    271         // bytes.
    272         char c = *s2++;
    273         if (*s2 == '\0') {
    274           size_t mul;
    275           if (c == '\0') {
    276             mul = 1;
    277           } else if (c == 'k' || c == 'K') {
    278             mul = KB;
    279           } else if (c == 'm' || c == 'M') {
    280             mul = MB;
    281           } else if (c == 'g' || c == 'G') {
    282             mul = GB;
    283           } else {
    284             // Unknown multiplier character.
    285             return 0;
    286           }
    287 
    288           if (val <= std::numeric_limits<size_t>::max() / mul) {
    289             val *= mul;
    290           } else {
    291             // Clamp to a multiple of 1024.
    292             val = std::numeric_limits<size_t>::max() & ~(1024-1);
    293           }
    294         } else {
    295           // There's more than one character after the numeric part.
    296           return 0;
    297         }
    298       }
    299       // The man page says that a -Xm value must be a multiple of 1024.
    300       if (val % div == 0) {
    301         return val;
    302       }
    303     }
    304   }
    305   return 0;
    306 }
    307 
    308 size_t ParseIntegerOrDie(const std::string& s) {
    309   std::string::size_type colon = s.find(':');
    310   if (colon == std::string::npos) {
    311     LOG(FATAL) << "Missing integer: " << s;
    312   }
    313   const char* begin = &s[colon + 1];
    314   char* end;
    315   size_t result = strtoul(begin, &end, 10);
    316   if (begin == end || *end != '\0') {
    317     LOG(FATAL) << "Failed to parse integer in: " << s;
    318   }
    319   return result;
    320 }
    321 
    322 Runtime::ParsedOptions* Runtime::ParsedOptions::Create(const Options& options, bool ignore_unrecognized) {
    323   UniquePtr<ParsedOptions> parsed(new ParsedOptions());
    324   const char* boot_class_path_string = getenv("BOOTCLASSPATH");
    325   if (boot_class_path_string != NULL) {
    326     parsed->boot_class_path_string_ = boot_class_path_string;
    327   }
    328   const char* class_path_string = getenv("CLASSPATH");
    329   if (class_path_string != NULL) {
    330     parsed->class_path_string_ = class_path_string;
    331   }
    332   // -Xcheck:jni is off by default for regular builds but on by default in debug builds.
    333   parsed->check_jni_ = kIsDebugBuild;
    334 
    335   parsed->heap_initial_size_ = gc::Heap::kDefaultInitialSize;
    336   parsed->heap_maximum_size_ = gc::Heap::kDefaultMaximumSize;
    337   parsed->heap_min_free_ = gc::Heap::kDefaultMinFree;
    338   parsed->heap_max_free_ = gc::Heap::kDefaultMaxFree;
    339   parsed->heap_target_utilization_ = gc::Heap::kDefaultTargetUtilization;
    340   parsed->heap_growth_limit_ = 0;  // 0 means no growth limit.
    341   // Default to number of processors minus one since the main GC thread also does work.
    342   parsed->parallel_gc_threads_ = sysconf(_SC_NPROCESSORS_CONF) - 1;
    343   // Only the main GC thread, no workers.
    344   parsed->conc_gc_threads_ = 0;
    345   parsed->stack_size_ = 0;  // 0 means default.
    346   parsed->low_memory_mode_ = false;
    347 
    348   parsed->is_compiler_ = false;
    349   parsed->is_zygote_ = false;
    350   parsed->interpreter_only_ = false;
    351   parsed->is_concurrent_gc_enabled_ = true;
    352   parsed->is_explicit_gc_disabled_ = false;
    353 
    354   parsed->long_pause_log_threshold_ = gc::Heap::kDefaultLongPauseLogThreshold;
    355   parsed->long_gc_log_threshold_ = gc::Heap::kDefaultLongGCLogThreshold;
    356   parsed->ignore_max_footprint_ = false;
    357 
    358   parsed->lock_profiling_threshold_ = 0;
    359   parsed->hook_is_sensitive_thread_ = NULL;
    360 
    361   parsed->hook_vfprintf_ = vfprintf;
    362   parsed->hook_exit_ = exit;
    363   parsed->hook_abort_ = NULL;  // We don't call abort(3) by default; see Runtime::Abort.
    364 
    365   parsed->compiler_filter_ = Runtime::kDefaultCompilerFilter;
    366   parsed->huge_method_threshold_ = Runtime::kDefaultHugeMethodThreshold;
    367   parsed->large_method_threshold_ = Runtime::kDefaultLargeMethodThreshold;
    368   parsed->small_method_threshold_ = Runtime::kDefaultSmallMethodThreshold;
    369   parsed->tiny_method_threshold_ = Runtime::kDefaultTinyMethodThreshold;
    370   parsed->num_dex_methods_threshold_ = Runtime::kDefaultNumDexMethodsThreshold;
    371 
    372   parsed->sea_ir_mode_ = false;
    373 //  gLogVerbosity.class_linker = true;  // TODO: don't check this in!
    374 //  gLogVerbosity.compiler = true;  // TODO: don't check this in!
    375 //  gLogVerbosity.verifier = true;  // TODO: don't check this in!
    376 //  gLogVerbosity.heap = true;  // TODO: don't check this in!
    377 //  gLogVerbosity.gc = true;  // TODO: don't check this in!
    378 //  gLogVerbosity.jdwp = true;  // TODO: don't check this in!
    379 //  gLogVerbosity.jni = true;  // TODO: don't check this in!
    380 //  gLogVerbosity.monitor = true;  // TODO: don't check this in!
    381 //  gLogVerbosity.startup = true;  // TODO: don't check this in!
    382 //  gLogVerbosity.third_party_jni = true;  // TODO: don't check this in!
    383 //  gLogVerbosity.threads = true;  // TODO: don't check this in!
    384 
    385   parsed->method_trace_ = false;
    386   parsed->method_trace_file_ = "/data/method-trace-file.bin";
    387   parsed->method_trace_file_size_ = 10 * MB;
    388 
    389   for (size_t i = 0; i < options.size(); ++i) {
    390     const std::string option(options[i].first);
    391     if (true && options[0].first == "-Xzygote") {
    392       LOG(INFO) << "option[" << i << "]=" << option;
    393     }
    394     if (StartsWith(option, "-Xbootclasspath:")) {
    395       parsed->boot_class_path_string_ = option.substr(strlen("-Xbootclasspath:")).data();
    396     } else if (option == "-classpath" || option == "-cp") {
    397       // TODO: support -Djava.class.path
    398       i++;
    399       if (i == options.size()) {
    400         // TODO: usage
    401         LOG(FATAL) << "Missing required class path value for " << option;
    402         return NULL;
    403       }
    404       const StringPiece& value = options[i].first;
    405       parsed->class_path_string_ = value.data();
    406     } else if (option == "bootclasspath") {
    407       parsed->boot_class_path_
    408           = reinterpret_cast<const std::vector<const DexFile*>*>(options[i].second);
    409     } else if (StartsWith(option, "-Ximage:")) {
    410       parsed->image_ = option.substr(strlen("-Ximage:")).data();
    411     } else if (StartsWith(option, "-Xcheck:jni")) {
    412       parsed->check_jni_ = true;
    413     } else if (StartsWith(option, "-Xrunjdwp:") || StartsWith(option, "-agentlib:jdwp=")) {
    414       std::string tail(option.substr(option[1] == 'X' ? 10 : 15));
    415       if (tail == "help" || !Dbg::ParseJdwpOptions(tail)) {
    416         LOG(FATAL) << "Example: -Xrunjdwp:transport=dt_socket,address=8000,server=y\n"
    417                    << "Example: -Xrunjdwp:transport=dt_socket,address=localhost:6500,server=n";
    418         return NULL;
    419       }
    420     } else if (StartsWith(option, "-Xms")) {
    421       size_t size = ParseMemoryOption(option.substr(strlen("-Xms")).c_str(), 1024);
    422       if (size == 0) {
    423         if (ignore_unrecognized) {
    424           continue;
    425         }
    426         // TODO: usage
    427         LOG(FATAL) << "Failed to parse " << option;
    428         return NULL;
    429       }
    430       parsed->heap_initial_size_ = size;
    431     } else if (StartsWith(option, "-Xmx")) {
    432       size_t size = ParseMemoryOption(option.substr(strlen("-Xmx")).c_str(), 1024);
    433       if (size == 0) {
    434         if (ignore_unrecognized) {
    435           continue;
    436         }
    437         // TODO: usage
    438         LOG(FATAL) << "Failed to parse " << option;
    439         return NULL;
    440       }
    441       parsed->heap_maximum_size_ = size;
    442     } else if (StartsWith(option, "-XX:HeapGrowthLimit=")) {
    443       size_t size = ParseMemoryOption(option.substr(strlen("-XX:HeapGrowthLimit=")).c_str(), 1024);
    444       if (size == 0) {
    445         if (ignore_unrecognized) {
    446           continue;
    447         }
    448         // TODO: usage
    449         LOG(FATAL) << "Failed to parse " << option;
    450         return NULL;
    451       }
    452       parsed->heap_growth_limit_ = size;
    453     } else if (StartsWith(option, "-XX:HeapMinFree=")) {
    454       size_t size = ParseMemoryOption(option.substr(strlen("-XX:HeapMinFree=")).c_str(), 1024);
    455       if (size == 0) {
    456         if (ignore_unrecognized) {
    457           continue;
    458         }
    459         // TODO: usage
    460         LOG(FATAL) << "Failed to parse " << option;
    461         return NULL;
    462       }
    463       parsed->heap_min_free_ = size;
    464     } else if (StartsWith(option, "-XX:HeapMaxFree=")) {
    465       size_t size = ParseMemoryOption(option.substr(strlen("-XX:HeapMaxFree=")).c_str(), 1024);
    466       if (size == 0) {
    467         if (ignore_unrecognized) {
    468           continue;
    469         }
    470         // TODO: usage
    471         LOG(FATAL) << "Failed to parse " << option;
    472         return NULL;
    473       }
    474       parsed->heap_max_free_ = size;
    475     } else if (StartsWith(option, "-XX:HeapTargetUtilization=")) {
    476       std::istringstream iss(option.substr(strlen("-XX:HeapTargetUtilization=")));
    477       double value;
    478       iss >> value;
    479       // Ensure that we have a value, there was no cruft after it and it satisfies a sensible range.
    480       const bool sane_val = iss.eof() && (value >= 0.1) && (value <= 0.9);
    481       if (!sane_val) {
    482         if (ignore_unrecognized) {
    483           continue;
    484         }
    485         LOG(FATAL) << "Invalid option '" << option << "'";
    486         return NULL;
    487       }
    488       parsed->heap_target_utilization_ = value;
    489     } else if (StartsWith(option, "-XX:ParallelGCThreads=")) {
    490       parsed->parallel_gc_threads_ =
    491           ParseMemoryOption(option.substr(strlen("-XX:ParallelGCThreads=")).c_str(), 1024);
    492     } else if (StartsWith(option, "-XX:ConcGCThreads=")) {
    493       parsed->conc_gc_threads_ =
    494           ParseMemoryOption(option.substr(strlen("-XX:ConcGCThreads=")).c_str(), 1024);
    495     } else if (StartsWith(option, "-Xss")) {
    496       size_t size = ParseMemoryOption(option.substr(strlen("-Xss")).c_str(), 1);
    497       if (size == 0) {
    498         if (ignore_unrecognized) {
    499           continue;
    500         }
    501         // TODO: usage
    502         LOG(FATAL) << "Failed to parse " << option;
    503         return NULL;
    504       }
    505       parsed->stack_size_ = size;
    506     } else if (option == "-XX:LongPauseLogThreshold") {
    507       parsed->long_pause_log_threshold_ =
    508           ParseMemoryOption(option.substr(strlen("-XX:LongPauseLogThreshold=")).c_str(), 1024);
    509     } else if (option == "-XX:LongGCLogThreshold") {
    510           parsed->long_gc_log_threshold_ =
    511               ParseMemoryOption(option.substr(strlen("-XX:LongGCLogThreshold")).c_str(), 1024);
    512     } else if (option == "-XX:IgnoreMaxFootprint") {
    513       parsed->ignore_max_footprint_ = true;
    514     } else if (option == "-XX:LowMemoryMode") {
    515       parsed->low_memory_mode_ = true;
    516     } else if (StartsWith(option, "-D")) {
    517       parsed->properties_.push_back(option.substr(strlen("-D")));
    518     } else if (StartsWith(option, "-Xjnitrace:")) {
    519       parsed->jni_trace_ = option.substr(strlen("-Xjnitrace:"));
    520     } else if (option == "compiler") {
    521       parsed->is_compiler_ = true;
    522     } else if (option == "-Xzygote") {
    523       parsed->is_zygote_ = true;
    524     } else if (option == "-Xint") {
    525       parsed->interpreter_only_ = true;
    526     } else if (StartsWith(option, "-Xgc:")) {
    527       std::vector<std::string> gc_options;
    528       Split(option.substr(strlen("-Xgc:")), ',', gc_options);
    529       for (size_t i = 0; i < gc_options.size(); ++i) {
    530         if (gc_options[i] == "noconcurrent") {
    531           parsed->is_concurrent_gc_enabled_ = false;
    532         } else if (gc_options[i] == "concurrent") {
    533           parsed->is_concurrent_gc_enabled_ = true;
    534         } else {
    535           LOG(WARNING) << "Ignoring unknown -Xgc option: " << gc_options[i];
    536         }
    537       }
    538     } else if (option == "-XX:+DisableExplicitGC") {
    539       parsed->is_explicit_gc_disabled_ = true;
    540     } else if (StartsWith(option, "-verbose:")) {
    541       std::vector<std::string> verbose_options;
    542       Split(option.substr(strlen("-verbose:")), ',', verbose_options);
    543       for (size_t i = 0; i < verbose_options.size(); ++i) {
    544         if (verbose_options[i] == "class") {
    545           gLogVerbosity.class_linker = true;
    546         } else if (verbose_options[i] == "verifier") {
    547           gLogVerbosity.verifier = true;
    548         } else if (verbose_options[i] == "compiler") {
    549           gLogVerbosity.compiler = true;
    550         } else if (verbose_options[i] == "heap") {
    551           gLogVerbosity.heap = true;
    552         } else if (verbose_options[i] == "gc") {
    553           gLogVerbosity.gc = true;
    554         } else if (verbose_options[i] == "jdwp") {
    555           gLogVerbosity.jdwp = true;
    556         } else if (verbose_options[i] == "jni") {
    557           gLogVerbosity.jni = true;
    558         } else if (verbose_options[i] == "monitor") {
    559           gLogVerbosity.monitor = true;
    560         } else if (verbose_options[i] == "startup") {
    561           gLogVerbosity.startup = true;
    562         } else if (verbose_options[i] == "third-party-jni") {
    563           gLogVerbosity.third_party_jni = true;
    564         } else if (verbose_options[i] == "threads") {
    565           gLogVerbosity.threads = true;
    566         } else {
    567           LOG(WARNING) << "Ignoring unknown -verbose option: " << verbose_options[i];
    568         }
    569       }
    570     } else if (StartsWith(option, "-Xjnigreflimit:")) {
    571       // Silently ignored for backwards compatibility.
    572     } else if (StartsWith(option, "-Xlockprofthreshold:")) {
    573       parsed->lock_profiling_threshold_ = ParseIntegerOrDie(option);
    574     } else if (StartsWith(option, "-Xstacktracefile:")) {
    575       parsed->stack_trace_file_ = option.substr(strlen("-Xstacktracefile:"));
    576     } else if (option == "sensitiveThread") {
    577       parsed->hook_is_sensitive_thread_ = reinterpret_cast<bool (*)()>(const_cast<void*>(options[i].second));
    578     } else if (option == "vfprintf") {
    579       parsed->hook_vfprintf_ =
    580           reinterpret_cast<int (*)(FILE *, const char*, va_list)>(const_cast<void*>(options[i].second));
    581     } else if (option == "exit") {
    582       parsed->hook_exit_ = reinterpret_cast<void(*)(jint)>(const_cast<void*>(options[i].second));
    583     } else if (option == "abort") {
    584       parsed->hook_abort_ = reinterpret_cast<void(*)()>(const_cast<void*>(options[i].second));
    585     } else if (option == "host-prefix") {
    586       parsed->host_prefix_ = reinterpret_cast<const char*>(options[i].second);
    587     } else if (option == "-Xgenregmap" || option == "-Xgc:precise") {
    588       // We silently ignore these for backwards compatibility.
    589     } else if (option == "-Xmethod-trace") {
    590       parsed->method_trace_ = true;
    591     } else if (StartsWith(option, "-Xmethod-trace-file:")) {
    592       parsed->method_trace_file_ = option.substr(strlen("-Xmethod-trace-file:"));
    593     } else if (StartsWith(option, "-Xmethod-trace-file-size:")) {
    594       parsed->method_trace_file_size_ = ParseIntegerOrDie(option);
    595     } else if (option == "-Xprofile:threadcpuclock") {
    596       Trace::SetDefaultClockSource(kProfilerClockSourceThreadCpu);
    597     } else if (option == "-Xprofile:wallclock") {
    598       Trace::SetDefaultClockSource(kProfilerClockSourceWall);
    599     } else if (option == "-Xprofile:dualclock") {
    600       Trace::SetDefaultClockSource(kProfilerClockSourceDual);
    601     } else if (option == "-compiler-filter:interpret-only") {
    602       parsed->compiler_filter_ = kInterpretOnly;
    603     } else if (option == "-compiler-filter:space") {
    604       parsed->compiler_filter_ = kSpace;
    605     } else if (option == "-compiler-filter:balanced") {
    606       parsed->compiler_filter_ = kBalanced;
    607     } else if (option == "-compiler-filter:speed") {
    608       parsed->compiler_filter_ = kSpeed;
    609     } else if (option == "-compiler-filter:everything") {
    610       parsed->compiler_filter_ = kEverything;
    611     } else if (option == "-sea_ir") {
    612       parsed->sea_ir_mode_ = true;
    613     } else if (StartsWith(option, "-huge-method-max:")) {
    614       parsed->huge_method_threshold_ = ParseIntegerOrDie(option);
    615     } else if (StartsWith(option, "-large-method-max:")) {
    616       parsed->large_method_threshold_ = ParseIntegerOrDie(option);
    617     } else if (StartsWith(option, "-small-method-max:")) {
    618       parsed->small_method_threshold_ = ParseIntegerOrDie(option);
    619     } else if (StartsWith(option, "-tiny-method-max:")) {
    620       parsed->tiny_method_threshold_ = ParseIntegerOrDie(option);
    621     } else if (StartsWith(option, "-num-dex-methods-max:")) {
    622       parsed->num_dex_methods_threshold_ = ParseIntegerOrDie(option);
    623     } else {
    624       if (!ignore_unrecognized) {
    625         // TODO: print usage via vfprintf
    626         LOG(ERROR) << "Unrecognized option " << option;
    627         // TODO: this should exit, but for now tolerate unknown options
    628         // return NULL;
    629       }
    630     }
    631   }
    632 
    633   // If a reference to the dalvik core.jar snuck in, replace it with
    634   // the art specific version. This can happen with on device
    635   // boot.art/boot.oat generation by GenerateImage which relies on the
    636   // value of BOOTCLASSPATH.
    637   std::string core_jar("/core.jar");
    638   size_t core_jar_pos = parsed->boot_class_path_string_.find(core_jar);
    639   if (core_jar_pos != std::string::npos) {
    640     parsed->boot_class_path_string_.replace(core_jar_pos, core_jar.size(), "/core-libart.jar");
    641   }
    642 
    643   if (!parsed->is_compiler_ && parsed->image_.empty()) {
    644     parsed->image_ += GetAndroidRoot();
    645     parsed->image_ += "/framework/boot.art";
    646   }
    647   if (parsed->heap_growth_limit_ == 0) {
    648     parsed->heap_growth_limit_ = parsed->heap_maximum_size_;
    649   }
    650 
    651   return parsed.release();
    652 }
    653 
    654 bool Runtime::Create(const Options& options, bool ignore_unrecognized) {
    655   // TODO: acquire a static mutex on Runtime to avoid racing.
    656   if (Runtime::instance_ != NULL) {
    657     return false;
    658   }
    659   InitLogging(NULL);  // Calls Locks::Init() as a side effect.
    660   instance_ = new Runtime;
    661   if (!instance_->Init(options, ignore_unrecognized)) {
    662     delete instance_;
    663     instance_ = NULL;
    664     return false;
    665   }
    666   return true;
    667 }
    668 
    669 jobject CreateSystemClassLoader() {
    670   if (Runtime::Current()->UseCompileTimeClassPath()) {
    671     return NULL;
    672   }
    673 
    674   ScopedObjectAccess soa(Thread::Current());
    675 
    676   mirror::Class* class_loader_class =
    677       soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_ClassLoader);
    678   CHECK(Runtime::Current()->GetClassLinker()->EnsureInitialized(class_loader_class, true, true));
    679 
    680   mirror::ArtMethod* getSystemClassLoader =
    681       class_loader_class->FindDirectMethod("getSystemClassLoader", "()Ljava/lang/ClassLoader;");
    682   CHECK(getSystemClassLoader != NULL);
    683 
    684   JValue result;
    685   ArgArray arg_array(NULL, 0);
    686   InvokeWithArgArray(soa, getSystemClassLoader, &arg_array, &result, 'L');
    687   mirror::ClassLoader* class_loader = down_cast<mirror::ClassLoader*>(result.GetL());
    688   CHECK(class_loader != NULL);
    689 
    690   JNIEnv* env = soa.Self()->GetJniEnv();
    691   ScopedLocalRef<jobject> system_class_loader(env, soa.AddLocalReference<jobject>(class_loader));
    692   CHECK(system_class_loader.get() != NULL);
    693 
    694   soa.Self()->SetClassLoaderOverride(class_loader);
    695 
    696   mirror::Class* thread_class = soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_Thread);
    697   CHECK(Runtime::Current()->GetClassLinker()->EnsureInitialized(thread_class, true, true));
    698 
    699   mirror::ArtField* contextClassLoader = thread_class->FindDeclaredInstanceField("contextClassLoader",
    700                                                                                  "Ljava/lang/ClassLoader;");
    701   CHECK(contextClassLoader != NULL);
    702 
    703   contextClassLoader->SetObject(soa.Self()->GetPeer(), class_loader);
    704 
    705   return env->NewGlobalRef(system_class_loader.get());
    706 }
    707 
    708 bool Runtime::Start() {
    709   VLOG(startup) << "Runtime::Start entering";
    710 
    711   CHECK(host_prefix_.empty()) << host_prefix_;
    712 
    713   // Restore main thread state to kNative as expected by native code.
    714   Thread* self = Thread::Current();
    715   self->TransitionFromRunnableToSuspended(kNative);
    716 
    717   started_ = true;
    718 
    719   // InitNativeMethods needs to be after started_ so that the classes
    720   // it touches will have methods linked to the oat file if necessary.
    721   InitNativeMethods();
    722 
    723   // Initialize well known thread group values that may be accessed threads while attaching.
    724   InitThreadGroups(self);
    725 
    726   Thread::FinishStartup();
    727 
    728   if (is_zygote_) {
    729     if (!InitZygote()) {
    730       return false;
    731     }
    732   } else {
    733     DidForkFromZygote();
    734   }
    735 
    736   StartDaemonThreads();
    737 
    738   system_class_loader_ = CreateSystemClassLoader();
    739 
    740   self->GetJniEnv()->locals.AssertEmpty();
    741 
    742   VLOG(startup) << "Runtime::Start exiting";
    743 
    744   finished_starting_ = true;
    745 
    746   return true;
    747 }
    748 
    749 void Runtime::EndThreadBirth() EXCLUSIVE_LOCKS_REQUIRED(Locks::runtime_shutdown_lock_) {
    750   DCHECK_GT(threads_being_born_, 0U);
    751   threads_being_born_--;
    752   if (shutting_down_started_ && threads_being_born_ == 0) {
    753     shutdown_cond_->Broadcast(Thread::Current());
    754   }
    755 }
    756 
    757 // Do zygote-mode-only initialization.
    758 bool Runtime::InitZygote() {
    759   // zygote goes into its own process group
    760   setpgid(0, 0);
    761 
    762   // See storage config details at http://source.android.com/tech/storage/
    763   // Create private mount namespace shared by all children
    764   if (unshare(CLONE_NEWNS) == -1) {
    765     PLOG(WARNING) << "Failed to unshare()";
    766     return false;
    767   }
    768 
    769   // Mark rootfs as being a slave so that changes from default
    770   // namespace only flow into our children.
    771   if (mount("rootfs", "/", NULL, (MS_SLAVE | MS_REC), NULL) == -1) {
    772     PLOG(WARNING) << "Failed to mount() rootfs as MS_SLAVE";
    773     return false;
    774   }
    775 
    776   // Create a staging tmpfs that is shared by our children; they will
    777   // bind mount storage into their respective private namespaces, which
    778   // are isolated from each other.
    779   const char* target_base = getenv("EMULATED_STORAGE_TARGET");
    780   if (target_base != NULL) {
    781     if (mount("tmpfs", target_base, "tmpfs", MS_NOSUID | MS_NODEV,
    782               "uid=0,gid=1028,mode=0751") == -1) {
    783       LOG(WARNING) << "Failed to mount tmpfs to " << target_base;
    784       return false;
    785     }
    786   }
    787 
    788   return true;
    789 }
    790 
    791 void Runtime::DidForkFromZygote() {
    792   is_zygote_ = false;
    793 
    794   // Create the thread pool.
    795   heap_->CreateThreadPool();
    796 
    797   StartSignalCatcher();
    798 
    799   // Start the JDWP thread. If the command-line debugger flags specified "suspend=y",
    800   // this will pause the runtime, so we probably want this to come last.
    801   Dbg::StartJdwp();
    802 }
    803 
    804 void Runtime::StartSignalCatcher() {
    805   if (!is_zygote_) {
    806     signal_catcher_ = new SignalCatcher(stack_trace_file_);
    807   }
    808 }
    809 
    810 void Runtime::StartDaemonThreads() {
    811   VLOG(startup) << "Runtime::StartDaemonThreads entering";
    812 
    813   Thread* self = Thread::Current();
    814 
    815   // Must be in the kNative state for calling native methods.
    816   CHECK_EQ(self->GetState(), kNative);
    817 
    818   JNIEnv* env = self->GetJniEnv();
    819   env->CallStaticVoidMethod(WellKnownClasses::java_lang_Daemons,
    820                             WellKnownClasses::java_lang_Daemons_start);
    821   if (env->ExceptionCheck()) {
    822     env->ExceptionDescribe();
    823     LOG(FATAL) << "Error starting java.lang.Daemons";
    824   }
    825 
    826   VLOG(startup) << "Runtime::StartDaemonThreads exiting";
    827 }
    828 
    829 bool Runtime::Init(const Options& raw_options, bool ignore_unrecognized) {
    830   CHECK_EQ(sysconf(_SC_PAGE_SIZE), kPageSize);
    831 
    832   UniquePtr<ParsedOptions> options(ParsedOptions::Create(raw_options, ignore_unrecognized));
    833   if (options.get() == NULL) {
    834     LOG(ERROR) << "Failed to parse options";
    835     return false;
    836   }
    837   VLOG(startup) << "Runtime::Init -verbose:startup enabled";
    838 
    839   QuasiAtomic::Startup();
    840 
    841   Monitor::Init(options->lock_profiling_threshold_, options->hook_is_sensitive_thread_);
    842 
    843   host_prefix_ = options->host_prefix_;
    844   boot_class_path_string_ = options->boot_class_path_string_;
    845   class_path_string_ = options->class_path_string_;
    846   properties_ = options->properties_;
    847 
    848   is_compiler_ = options->is_compiler_;
    849   is_zygote_ = options->is_zygote_;
    850   is_concurrent_gc_enabled_ = options->is_concurrent_gc_enabled_;
    851   is_explicit_gc_disabled_ = options->is_explicit_gc_disabled_;
    852 
    853   compiler_filter_ = options->compiler_filter_;
    854   huge_method_threshold_ = options->huge_method_threshold_;
    855   large_method_threshold_ = options->large_method_threshold_;
    856   small_method_threshold_ = options->small_method_threshold_;
    857   tiny_method_threshold_ = options->tiny_method_threshold_;
    858   num_dex_methods_threshold_ = options->num_dex_methods_threshold_;
    859 
    860   sea_ir_mode_ = options->sea_ir_mode_;
    861   vfprintf_ = options->hook_vfprintf_;
    862   exit_ = options->hook_exit_;
    863   abort_ = options->hook_abort_;
    864 
    865   default_stack_size_ = options->stack_size_;
    866   stack_trace_file_ = options->stack_trace_file_;
    867 
    868   monitor_list_ = new MonitorList;
    869   thread_list_ = new ThreadList;
    870   intern_table_ = new InternTable;
    871 
    872 
    873   if (options->interpreter_only_) {
    874     GetInstrumentation()->ForceInterpretOnly();
    875   }
    876 
    877   heap_ = new gc::Heap(options->heap_initial_size_,
    878                        options->heap_growth_limit_,
    879                        options->heap_min_free_,
    880                        options->heap_max_free_,
    881                        options->heap_target_utilization_,
    882                        options->heap_maximum_size_,
    883                        options->image_,
    884                        options->is_concurrent_gc_enabled_,
    885                        options->parallel_gc_threads_,
    886                        options->conc_gc_threads_,
    887                        options->low_memory_mode_,
    888                        options->long_pause_log_threshold_,
    889                        options->long_gc_log_threshold_,
    890                        options->ignore_max_footprint_);
    891 
    892   BlockSignals();
    893   InitPlatformSignalHandlers();
    894 
    895   java_vm_ = new JavaVMExt(this, options.get());
    896 
    897   Thread::Startup();
    898 
    899   // ClassLinker needs an attached thread, but we can't fully attach a thread without creating
    900   // objects. We can't supply a thread group yet; it will be fixed later. Since we are the main
    901   // thread, we do not get a java peer.
    902   Thread* self = Thread::Attach("main", false, NULL, false);
    903   CHECK_EQ(self->thin_lock_id_, ThreadList::kMainId);
    904   CHECK(self != NULL);
    905 
    906   // Set us to runnable so tools using a runtime can allocate and GC by default
    907   self->TransitionFromSuspendedToRunnable();
    908 
    909   // Now we're attached, we can take the heap locks and validate the heap.
    910   GetHeap()->EnableObjectValidation();
    911 
    912   CHECK_GE(GetHeap()->GetContinuousSpaces().size(), 1U);
    913   if (GetHeap()->GetContinuousSpaces()[0]->IsImageSpace()) {
    914     class_linker_ = ClassLinker::CreateFromImage(intern_table_);
    915   } else {
    916     CHECK(options->boot_class_path_ != NULL);
    917     CHECK_NE(options->boot_class_path_->size(), 0U);
    918     class_linker_ = ClassLinker::CreateFromCompiler(*options->boot_class_path_, intern_table_);
    919   }
    920   CHECK(class_linker_ != NULL);
    921   verifier::MethodVerifier::Init();
    922 
    923   method_trace_ = options->method_trace_;
    924   method_trace_file_ = options->method_trace_file_;
    925   method_trace_file_size_ = options->method_trace_file_size_;
    926 
    927   if (options->method_trace_) {
    928     Trace::Start(options->method_trace_file_.c_str(), -1, options->method_trace_file_size_, 0,
    929                  false, false, 0);
    930   }
    931 
    932   // Pre-allocate an OutOfMemoryError for the double-OOME case.
    933   self->ThrowNewException(ThrowLocation(), "Ljava/lang/OutOfMemoryError;",
    934                           "OutOfMemoryError thrown while trying to throw OutOfMemoryError; no stack available");
    935   pre_allocated_OutOfMemoryError_ = self->GetException(NULL);
    936   self->ClearException();
    937 
    938   VLOG(startup) << "Runtime::Init exiting";
    939   return true;
    940 }
    941 
    942 void Runtime::InitNativeMethods() {
    943   VLOG(startup) << "Runtime::InitNativeMethods entering";
    944   Thread* self = Thread::Current();
    945   JNIEnv* env = self->GetJniEnv();
    946 
    947   // Must be in the kNative state for calling native methods (JNI_OnLoad code).
    948   CHECK_EQ(self->GetState(), kNative);
    949 
    950   // First set up JniConstants, which is used by both the runtime's built-in native
    951   // methods and libcore.
    952   JniConstants::init(env);
    953   WellKnownClasses::Init(env);
    954 
    955   // Then set up the native methods provided by the runtime itself.
    956   RegisterRuntimeNativeMethods(env);
    957 
    958   // Then set up libcore, which is just a regular JNI library with a regular JNI_OnLoad.
    959   // Most JNI libraries can just use System.loadLibrary, but libcore can't because it's
    960   // the library that implements System.loadLibrary!
    961   {
    962     std::string mapped_name(StringPrintf(OS_SHARED_LIB_FORMAT_STR, "javacore"));
    963     std::string reason;
    964     self->TransitionFromSuspendedToRunnable();
    965     if (!instance_->java_vm_->LoadNativeLibrary(mapped_name, NULL, reason)) {
    966       LOG(FATAL) << "LoadNativeLibrary failed for \"" << mapped_name << "\": " << reason;
    967     }
    968     self->TransitionFromRunnableToSuspended(kNative);
    969   }
    970 
    971   // Initialize well known classes that may invoke runtime native methods.
    972   WellKnownClasses::LateInit(env);
    973 
    974   VLOG(startup) << "Runtime::InitNativeMethods exiting";
    975 }
    976 
    977 void Runtime::InitThreadGroups(Thread* self) {
    978   JNIEnvExt* env = self->GetJniEnv();
    979   ScopedJniEnvLocalRefState env_state(env);
    980   main_thread_group_ =
    981       env->NewGlobalRef(env->GetStaticObjectField(WellKnownClasses::java_lang_ThreadGroup,
    982                                                   WellKnownClasses::java_lang_ThreadGroup_mainThreadGroup));
    983   CHECK(main_thread_group_ != NULL || IsCompiler());
    984   system_thread_group_ =
    985       env->NewGlobalRef(env->GetStaticObjectField(WellKnownClasses::java_lang_ThreadGroup,
    986                                                   WellKnownClasses::java_lang_ThreadGroup_systemThreadGroup));
    987   CHECK(system_thread_group_ != NULL || IsCompiler());
    988 }
    989 
    990 jobject Runtime::GetMainThreadGroup() const {
    991   CHECK(main_thread_group_ != NULL || IsCompiler());
    992   return main_thread_group_;
    993 }
    994 
    995 jobject Runtime::GetSystemThreadGroup() const {
    996   CHECK(system_thread_group_ != NULL || IsCompiler());
    997   return system_thread_group_;
    998 }
    999 
   1000 jobject Runtime::GetSystemClassLoader() const {
   1001   CHECK(system_class_loader_ != NULL || IsCompiler());
   1002   return system_class_loader_;
   1003 }
   1004 
   1005 void Runtime::RegisterRuntimeNativeMethods(JNIEnv* env) {
   1006 #define REGISTER(FN) extern void FN(JNIEnv*); FN(env)
   1007   // Register Throwable first so that registration of other native methods can throw exceptions
   1008   REGISTER(register_java_lang_Throwable);
   1009   REGISTER(register_dalvik_system_DexFile);
   1010   REGISTER(register_dalvik_system_VMDebug);
   1011   REGISTER(register_dalvik_system_VMRuntime);
   1012   REGISTER(register_dalvik_system_VMStack);
   1013   REGISTER(register_dalvik_system_Zygote);
   1014   REGISTER(register_java_lang_Class);
   1015   REGISTER(register_java_lang_DexCache);
   1016   REGISTER(register_java_lang_Object);
   1017   REGISTER(register_java_lang_Runtime);
   1018   REGISTER(register_java_lang_String);
   1019   REGISTER(register_java_lang_System);
   1020   REGISTER(register_java_lang_Thread);
   1021   REGISTER(register_java_lang_VMClassLoader);
   1022   REGISTER(register_java_lang_reflect_Array);
   1023   REGISTER(register_java_lang_reflect_Constructor);
   1024   REGISTER(register_java_lang_reflect_Field);
   1025   REGISTER(register_java_lang_reflect_Method);
   1026   REGISTER(register_java_lang_reflect_Proxy);
   1027   REGISTER(register_java_util_concurrent_atomic_AtomicLong);
   1028   REGISTER(register_org_apache_harmony_dalvik_ddmc_DdmServer);
   1029   REGISTER(register_org_apache_harmony_dalvik_ddmc_DdmVmInternal);
   1030   REGISTER(register_sun_misc_Unsafe);
   1031 #undef REGISTER
   1032 }
   1033 
   1034 void Runtime::DumpForSigQuit(std::ostream& os) {
   1035   GetClassLinker()->DumpForSigQuit(os);
   1036   GetInternTable()->DumpForSigQuit(os);
   1037   GetJavaVM()->DumpForSigQuit(os);
   1038   GetHeap()->DumpForSigQuit(os);
   1039   os << "\n";
   1040 
   1041   thread_list_->DumpForSigQuit(os);
   1042   BaseMutex::DumpAll(os);
   1043 }
   1044 
   1045 void Runtime::DumpLockHolders(std::ostream& os) {
   1046   uint64_t mutator_lock_owner = Locks::mutator_lock_->GetExclusiveOwnerTid();
   1047   pid_t thread_list_lock_owner = GetThreadList()->GetLockOwner();
   1048   pid_t classes_lock_owner = GetClassLinker()->GetClassesLockOwner();
   1049   pid_t dex_lock_owner = GetClassLinker()->GetDexLockOwner();
   1050   if ((thread_list_lock_owner | classes_lock_owner | dex_lock_owner) != 0) {
   1051     os << "Mutator lock exclusive owner tid: " << mutator_lock_owner << "\n"
   1052        << "ThreadList lock owner tid: " << thread_list_lock_owner << "\n"
   1053        << "ClassLinker classes lock owner tid: " << classes_lock_owner << "\n"
   1054        << "ClassLinker dex lock owner tid: " << dex_lock_owner << "\n";
   1055   }
   1056 }
   1057 
   1058 void Runtime::SetStatsEnabled(bool new_state) {
   1059   if (new_state == true) {
   1060     GetStats()->Clear(~0);
   1061     // TODO: wouldn't it make more sense to clear _all_ threads' stats?
   1062     Thread::Current()->GetStats()->Clear(~0);
   1063   }
   1064   stats_enabled_ = new_state;
   1065 }
   1066 
   1067 void Runtime::ResetStats(int kinds) {
   1068   GetStats()->Clear(kinds & 0xffff);
   1069   // TODO: wouldn't it make more sense to clear _all_ threads' stats?
   1070   Thread::Current()->GetStats()->Clear(kinds >> 16);
   1071 }
   1072 
   1073 int32_t Runtime::GetStat(int kind) {
   1074   RuntimeStats* stats;
   1075   if (kind < (1<<16)) {
   1076     stats = GetStats();
   1077   } else {
   1078     stats = Thread::Current()->GetStats();
   1079     kind >>= 16;
   1080   }
   1081   switch (kind) {
   1082   case KIND_ALLOCATED_OBJECTS:
   1083     return stats->allocated_objects;
   1084   case KIND_ALLOCATED_BYTES:
   1085     return stats->allocated_bytes;
   1086   case KIND_FREED_OBJECTS:
   1087     return stats->freed_objects;
   1088   case KIND_FREED_BYTES:
   1089     return stats->freed_bytes;
   1090   case KIND_GC_INVOCATIONS:
   1091     return stats->gc_for_alloc_count;
   1092   case KIND_CLASS_INIT_COUNT:
   1093     return stats->class_init_count;
   1094   case KIND_CLASS_INIT_TIME:
   1095     // Convert ns to us, reduce to 32 bits.
   1096     return static_cast<int>(stats->class_init_time_ns / 1000);
   1097   case KIND_EXT_ALLOCATED_OBJECTS:
   1098   case KIND_EXT_ALLOCATED_BYTES:
   1099   case KIND_EXT_FREED_OBJECTS:
   1100   case KIND_EXT_FREED_BYTES:
   1101     return 0;  // backward compatibility
   1102   default:
   1103     LOG(FATAL) << "Unknown statistic " << kind;
   1104     return -1;  // unreachable
   1105   }
   1106 }
   1107 
   1108 void Runtime::BlockSignals() {
   1109   SignalSet signals;
   1110   signals.Add(SIGPIPE);
   1111   // SIGQUIT is used to dump the runtime's state (including stack traces).
   1112   signals.Add(SIGQUIT);
   1113   // SIGUSR1 is used to initiate a GC.
   1114   signals.Add(SIGUSR1);
   1115   signals.Block();
   1116 }
   1117 
   1118 bool Runtime::AttachCurrentThread(const char* thread_name, bool as_daemon, jobject thread_group,
   1119                                   bool create_peer) {
   1120   bool success = Thread::Attach(thread_name, as_daemon, thread_group, create_peer) != NULL;
   1121   if (thread_name == NULL) {
   1122     LOG(WARNING) << *Thread::Current() << " attached without supplying a name";
   1123   }
   1124   return success;
   1125 }
   1126 
   1127 void Runtime::DetachCurrentThread() {
   1128   Thread* self = Thread::Current();
   1129   if (self == NULL) {
   1130     LOG(FATAL) << "attempting to detach thread that is not attached";
   1131   }
   1132   if (self->HasManagedStack()) {
   1133     LOG(FATAL) << *Thread::Current() << " attempting to detach while still running code";
   1134   }
   1135   thread_list_->Unregister(self);
   1136 }
   1137 
   1138   mirror::Throwable* Runtime::GetPreAllocatedOutOfMemoryError() const {
   1139   if (pre_allocated_OutOfMemoryError_ == NULL) {
   1140     LOG(ERROR) << "Failed to return pre-allocated OOME";
   1141   }
   1142   return pre_allocated_OutOfMemoryError_;
   1143 }
   1144 
   1145 void Runtime::VisitConcurrentRoots(RootVisitor* visitor, void* arg, bool only_dirty,
   1146                                    bool clean_dirty) {
   1147   intern_table_->VisitRoots(visitor, arg, only_dirty, clean_dirty);
   1148   class_linker_->VisitRoots(visitor, arg, only_dirty, clean_dirty);
   1149 }
   1150 
   1151 void Runtime::VisitNonThreadRoots(RootVisitor* visitor, void* arg) {
   1152   java_vm_->VisitRoots(visitor, arg);
   1153   if (pre_allocated_OutOfMemoryError_ != NULL) {
   1154     visitor(pre_allocated_OutOfMemoryError_, arg);
   1155   }
   1156   visitor(resolution_method_, arg);
   1157   for (int i = 0; i < Runtime::kLastCalleeSaveType; i++) {
   1158     visitor(callee_save_methods_[i], arg);
   1159   }
   1160 }
   1161 
   1162 void Runtime::VisitNonConcurrentRoots(RootVisitor* visitor, void* arg) {
   1163   thread_list_->VisitRoots(visitor, arg);
   1164   VisitNonThreadRoots(visitor, arg);
   1165 }
   1166 
   1167 void Runtime::VisitRoots(RootVisitor* visitor, void* arg, bool only_dirty, bool clean_dirty) {
   1168   VisitConcurrentRoots(visitor, arg, only_dirty, clean_dirty);
   1169   VisitNonConcurrentRoots(visitor, arg);
   1170 }
   1171 
   1172 mirror::ArtMethod* Runtime::CreateResolutionMethod() {
   1173   mirror::Class* method_class = mirror::ArtMethod::GetJavaLangReflectArtMethod();
   1174   Thread* self = Thread::Current();
   1175   SirtRef<mirror::ArtMethod>
   1176       method(self, down_cast<mirror::ArtMethod*>(method_class->AllocObject(self)));
   1177   method->SetDeclaringClass(method_class);
   1178   // TODO: use a special method for resolution method saves
   1179   method->SetDexMethodIndex(DexFile::kDexNoIndex);
   1180   // When compiling, the code pointer will get set later when the image is loaded.
   1181   Runtime* r = Runtime::Current();
   1182   ClassLinker* cl = r->GetClassLinker();
   1183   method->SetEntryPointFromCompiledCode(r->IsCompiler() ? NULL : GetResolutionTrampoline(cl));
   1184   return method.get();
   1185 }
   1186 
   1187 mirror::ArtMethod* Runtime::CreateCalleeSaveMethod(InstructionSet instruction_set,
   1188                                                         CalleeSaveType type) {
   1189   mirror::Class* method_class = mirror::ArtMethod::GetJavaLangReflectArtMethod();
   1190   Thread* self = Thread::Current();
   1191   SirtRef<mirror::ArtMethod>
   1192       method(self, down_cast<mirror::ArtMethod*>(method_class->AllocObject(self)));
   1193   method->SetDeclaringClass(method_class);
   1194   // TODO: use a special method for callee saves
   1195   method->SetDexMethodIndex(DexFile::kDexNoIndex);
   1196   method->SetEntryPointFromCompiledCode(NULL);
   1197   if ((instruction_set == kThumb2) || (instruction_set == kArm)) {
   1198     uint32_t ref_spills = (1 << art::arm::R5) | (1 << art::arm::R6)  | (1 << art::arm::R7) |
   1199                           (1 << art::arm::R8) | (1 << art::arm::R10) | (1 << art::arm::R11);
   1200     uint32_t arg_spills = (1 << art::arm::R1) | (1 << art::arm::R2) | (1 << art::arm::R3);
   1201     uint32_t all_spills = (1 << art::arm::R4) | (1 << art::arm::R9);
   1202     uint32_t core_spills = ref_spills | (type == kRefsAndArgs ? arg_spills : 0) |
   1203                            (type == kSaveAll ? all_spills : 0) | (1 << art::arm::LR);
   1204     uint32_t fp_all_spills = (1 << art::arm::S0)  | (1 << art::arm::S1)  | (1 << art::arm::S2) |
   1205                              (1 << art::arm::S3)  | (1 << art::arm::S4)  | (1 << art::arm::S5) |
   1206                              (1 << art::arm::S6)  | (1 << art::arm::S7)  | (1 << art::arm::S8) |
   1207                              (1 << art::arm::S9)  | (1 << art::arm::S10) | (1 << art::arm::S11) |
   1208                              (1 << art::arm::S12) | (1 << art::arm::S13) | (1 << art::arm::S14) |
   1209                              (1 << art::arm::S15) | (1 << art::arm::S16) | (1 << art::arm::S17) |
   1210                              (1 << art::arm::S18) | (1 << art::arm::S19) | (1 << art::arm::S20) |
   1211                              (1 << art::arm::S21) | (1 << art::arm::S22) | (1 << art::arm::S23) |
   1212                              (1 << art::arm::S24) | (1 << art::arm::S25) | (1 << art::arm::S26) |
   1213                              (1 << art::arm::S27) | (1 << art::arm::S28) | (1 << art::arm::S29) |
   1214                              (1 << art::arm::S30) | (1 << art::arm::S31);
   1215     uint32_t fp_spills = type == kSaveAll ? fp_all_spills : 0;
   1216     size_t frame_size = RoundUp((__builtin_popcount(core_spills) /* gprs */ +
   1217                                  __builtin_popcount(fp_spills) /* fprs */ +
   1218                                  1 /* Method* */) * kPointerSize, kStackAlignment);
   1219     method->SetFrameSizeInBytes(frame_size);
   1220     method->SetCoreSpillMask(core_spills);
   1221     method->SetFpSpillMask(fp_spills);
   1222   } else if (instruction_set == kMips) {
   1223     uint32_t ref_spills = (1 << art::mips::S2) | (1 << art::mips::S3) | (1 << art::mips::S4) |
   1224                           (1 << art::mips::S5) | (1 << art::mips::S6) | (1 << art::mips::S7) |
   1225                           (1 << art::mips::GP) | (1 << art::mips::FP);
   1226     uint32_t arg_spills = (1 << art::mips::A1) | (1 << art::mips::A2) | (1 << art::mips::A3);
   1227     uint32_t all_spills = (1 << art::mips::S0) | (1 << art::mips::S1);
   1228     uint32_t core_spills = ref_spills | (type == kRefsAndArgs ? arg_spills : 0) |
   1229                            (type == kSaveAll ? all_spills : 0) | (1 << art::mips::RA);
   1230     size_t frame_size = RoundUp((__builtin_popcount(core_spills) /* gprs */ +
   1231                                 (type == kRefsAndArgs ? 0 : 3) + 1 /* Method* */) *
   1232                                 kPointerSize, kStackAlignment);
   1233     method->SetFrameSizeInBytes(frame_size);
   1234     method->SetCoreSpillMask(core_spills);
   1235     method->SetFpSpillMask(0);
   1236   } else if (instruction_set == kX86) {
   1237     uint32_t ref_spills = (1 << art::x86::EBP) | (1 << art::x86::ESI) | (1 << art::x86::EDI);
   1238     uint32_t arg_spills = (1 << art::x86::ECX) | (1 << art::x86::EDX) | (1 << art::x86::EBX);
   1239     uint32_t core_spills = ref_spills | (type == kRefsAndArgs ? arg_spills : 0) |
   1240                          (1 << art::x86::kNumberOfCpuRegisters);  // fake return address callee save
   1241     size_t frame_size = RoundUp((__builtin_popcount(core_spills) /* gprs */ +
   1242                                  1 /* Method* */) * kPointerSize, kStackAlignment);
   1243     method->SetFrameSizeInBytes(frame_size);
   1244     method->SetCoreSpillMask(core_spills);
   1245     method->SetFpSpillMask(0);
   1246   } else {
   1247     UNIMPLEMENTED(FATAL);
   1248   }
   1249   return method.get();
   1250 }
   1251 
   1252 void Runtime::DisallowNewSystemWeaks() {
   1253   monitor_list_->DisallowNewMonitors();
   1254   intern_table_->DisallowNewInterns();
   1255   java_vm_->DisallowNewWeakGlobals();
   1256 }
   1257 
   1258 void Runtime::AllowNewSystemWeaks() {
   1259   monitor_list_->AllowNewMonitors();
   1260   intern_table_->AllowNewInterns();
   1261   java_vm_->AllowNewWeakGlobals();
   1262 }
   1263 
   1264 void Runtime::SetCalleeSaveMethod(mirror::ArtMethod* method, CalleeSaveType type) {
   1265   DCHECK_LT(static_cast<int>(type), static_cast<int>(kLastCalleeSaveType));
   1266   callee_save_methods_[type] = method;
   1267 }
   1268 
   1269 const std::vector<const DexFile*>& Runtime::GetCompileTimeClassPath(jobject class_loader) {
   1270   if (class_loader == NULL) {
   1271     return GetClassLinker()->GetBootClassPath();
   1272   }
   1273   CHECK(UseCompileTimeClassPath());
   1274   CompileTimeClassPaths::const_iterator it = compile_time_class_paths_.find(class_loader);
   1275   CHECK(it != compile_time_class_paths_.end());
   1276   return it->second;
   1277 }
   1278 
   1279 void Runtime::SetCompileTimeClassPath(jobject class_loader, std::vector<const DexFile*>& class_path) {
   1280   CHECK(!IsStarted());
   1281   use_compile_time_class_path_ = true;
   1282   compile_time_class_paths_.Put(class_loader, class_path);
   1283 }
   1284 
   1285 }  // namespace art
   1286