blob: d20f51001cab933e8c77979c66f204433dc424a9 [file] [log] [blame]
/*
* Copyright (C) 2011 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 "compiler_driver.h"
#include <unordered_set>
#include <vector>
#include <unistd.h>
#ifndef __APPLE__
#include <malloc.h> // For mallinfo
#endif
#include "art_field-inl.h"
#include "art_method-inl.h"
#include "base/stl_util.h"
#include "base/systrace.h"
#include "base/time_utils.h"
#include "base/timing_logger.h"
#include "class_linker-inl.h"
#include "compiled_class.h"
#include "compiled_method.h"
#include "compiler.h"
#include "compiler_driver-inl.h"
#include "dex_compilation_unit.h"
#include "dex_file-inl.h"
#include "dex_instruction-inl.h"
#include "dex/dex_to_dex_compiler.h"
#include "dex/verification_results.h"
#include "dex/verified_method.h"
#include "dex/quick/dex_file_method_inliner.h"
#include "dex/quick/dex_file_to_method_inliner_map.h"
#include "driver/compiler_options.h"
#include "jni_internal.h"
#include "object_lock.h"
#include "profiler.h"
#include "runtime.h"
#include "gc/accounting/card_table-inl.h"
#include "gc/accounting/heap_bitmap.h"
#include "gc/space/image_space.h"
#include "gc/space/space.h"
#include "mirror/class_loader.h"
#include "mirror/class-inl.h"
#include "mirror/dex_cache-inl.h"
#include "mirror/object-inl.h"
#include "mirror/object_array-inl.h"
#include "mirror/throwable.h"
#include "scoped_thread_state_change.h"
#include "ScopedLocalRef.h"
#include "handle_scope-inl.h"
#include "thread.h"
#include "thread_list.h"
#include "thread_pool.h"
#include "trampolines/trampoline_compiler.h"
#include "transaction.h"
#include "utils/dex_cache_arrays_layout-inl.h"
#include "utils/swap_space.h"
#include "verifier/method_verifier.h"
#include "verifier/method_verifier-inl.h"
namespace art {
static constexpr bool kTimeCompileMethod = !kIsDebugBuild;
// Whether classes-to-compile and methods-to-compile are only applied to the boot image, or, when
// given, too all compilations.
static constexpr bool kRestrictCompilationFiltersToImage = true;
// Print additional info during profile guided compilation.
static constexpr bool kDebugProfileGuidedCompilation = false;
static double Percentage(size_t x, size_t y) {
return 100.0 * (static_cast<double>(x)) / (static_cast<double>(x + y));
}
static void DumpStat(size_t x, size_t y, const char* str) {
if (x == 0 && y == 0) {
return;
}
LOG(INFO) << Percentage(x, y) << "% of " << str << " for " << (x + y) << " cases";
}
class CompilerDriver::AOTCompilationStats {
public:
AOTCompilationStats()
: stats_lock_("AOT compilation statistics lock"),
types_in_dex_cache_(0), types_not_in_dex_cache_(0),
strings_in_dex_cache_(0), strings_not_in_dex_cache_(0),
resolved_types_(0), unresolved_types_(0),
resolved_instance_fields_(0), unresolved_instance_fields_(0),
resolved_local_static_fields_(0), resolved_static_fields_(0), unresolved_static_fields_(0),
type_based_devirtualization_(0),
safe_casts_(0), not_safe_casts_(0) {
for (size_t i = 0; i <= kMaxInvokeType; i++) {
resolved_methods_[i] = 0;
unresolved_methods_[i] = 0;
virtual_made_direct_[i] = 0;
direct_calls_to_boot_[i] = 0;
direct_methods_to_boot_[i] = 0;
}
}
void Dump() {
DumpStat(types_in_dex_cache_, types_not_in_dex_cache_, "types known to be in dex cache");
DumpStat(strings_in_dex_cache_, strings_not_in_dex_cache_, "strings known to be in dex cache");
DumpStat(resolved_types_, unresolved_types_, "types resolved");
DumpStat(resolved_instance_fields_, unresolved_instance_fields_, "instance fields resolved");
DumpStat(resolved_local_static_fields_ + resolved_static_fields_, unresolved_static_fields_,
"static fields resolved");
DumpStat(resolved_local_static_fields_, resolved_static_fields_ + unresolved_static_fields_,
"static fields local to a class");
DumpStat(safe_casts_, not_safe_casts_, "check-casts removed based on type information");
// Note, the code below subtracts the stat value so that when added to the stat value we have
// 100% of samples. TODO: clean this up.
DumpStat(type_based_devirtualization_,
resolved_methods_[kVirtual] + unresolved_methods_[kVirtual] +
resolved_methods_[kInterface] + unresolved_methods_[kInterface] -
type_based_devirtualization_,
"virtual/interface calls made direct based on type information");
for (size_t i = 0; i <= kMaxInvokeType; i++) {
std::ostringstream oss;
oss << static_cast<InvokeType>(i) << " methods were AOT resolved";
DumpStat(resolved_methods_[i], unresolved_methods_[i], oss.str().c_str());
if (virtual_made_direct_[i] > 0) {
std::ostringstream oss2;
oss2 << static_cast<InvokeType>(i) << " methods made direct";
DumpStat(virtual_made_direct_[i],
resolved_methods_[i] + unresolved_methods_[i] - virtual_made_direct_[i],
oss2.str().c_str());
}
if (direct_calls_to_boot_[i] > 0) {
std::ostringstream oss2;
oss2 << static_cast<InvokeType>(i) << " method calls are direct into boot";
DumpStat(direct_calls_to_boot_[i],
resolved_methods_[i] + unresolved_methods_[i] - direct_calls_to_boot_[i],
oss2.str().c_str());
}
if (direct_methods_to_boot_[i] > 0) {
std::ostringstream oss2;
oss2 << static_cast<InvokeType>(i) << " method calls have methods in boot";
DumpStat(direct_methods_to_boot_[i],
resolved_methods_[i] + unresolved_methods_[i] - direct_methods_to_boot_[i],
oss2.str().c_str());
}
}
}
// Allow lossy statistics in non-debug builds.
#ifndef NDEBUG
#define STATS_LOCK() MutexLock mu(Thread::Current(), stats_lock_)
#else
#define STATS_LOCK()
#endif
void TypeInDexCache() REQUIRES(!stats_lock_) {
STATS_LOCK();
types_in_dex_cache_++;
}
void TypeNotInDexCache() REQUIRES(!stats_lock_) {
STATS_LOCK();
types_not_in_dex_cache_++;
}
void StringInDexCache() REQUIRES(!stats_lock_) {
STATS_LOCK();
strings_in_dex_cache_++;
}
void StringNotInDexCache() REQUIRES(!stats_lock_) {
STATS_LOCK();
strings_not_in_dex_cache_++;
}
void TypeDoesntNeedAccessCheck() REQUIRES(!stats_lock_) {
STATS_LOCK();
resolved_types_++;
}
void TypeNeedsAccessCheck() REQUIRES(!stats_lock_) {
STATS_LOCK();
unresolved_types_++;
}
void ResolvedInstanceField() REQUIRES(!stats_lock_) {
STATS_LOCK();
resolved_instance_fields_++;
}
void UnresolvedInstanceField() REQUIRES(!stats_lock_) {
STATS_LOCK();
unresolved_instance_fields_++;
}
void ResolvedLocalStaticField() REQUIRES(!stats_lock_) {
STATS_LOCK();
resolved_local_static_fields_++;
}
void ResolvedStaticField() REQUIRES(!stats_lock_) {
STATS_LOCK();
resolved_static_fields_++;
}
void UnresolvedStaticField() REQUIRES(!stats_lock_) {
STATS_LOCK();
unresolved_static_fields_++;
}
// Indicate that type information from the verifier led to devirtualization.
void PreciseTypeDevirtualization() REQUIRES(!stats_lock_) {
STATS_LOCK();
type_based_devirtualization_++;
}
// Indicate that a method of the given type was resolved at compile time.
void ResolvedMethod(InvokeType type) REQUIRES(!stats_lock_) {
DCHECK_LE(type, kMaxInvokeType);
STATS_LOCK();
resolved_methods_[type]++;
}
// Indicate that a method of the given type was unresolved at compile time as it was in an
// unknown dex file.
void UnresolvedMethod(InvokeType type) REQUIRES(!stats_lock_) {
DCHECK_LE(type, kMaxInvokeType);
STATS_LOCK();
unresolved_methods_[type]++;
}
// Indicate that a type of virtual method dispatch has been converted into a direct method
// dispatch.
void VirtualMadeDirect(InvokeType type) REQUIRES(!stats_lock_) {
DCHECK(type == kVirtual || type == kInterface || type == kSuper);
STATS_LOCK();
virtual_made_direct_[type]++;
}
// Indicate that a method of the given type was able to call directly into boot.
void DirectCallsToBoot(InvokeType type) REQUIRES(!stats_lock_) {
DCHECK_LE(type, kMaxInvokeType);
STATS_LOCK();
direct_calls_to_boot_[type]++;
}
// Indicate that a method of the given type was able to be resolved directly from boot.
void DirectMethodsToBoot(InvokeType type) REQUIRES(!stats_lock_) {
DCHECK_LE(type, kMaxInvokeType);
STATS_LOCK();
direct_methods_to_boot_[type]++;
}
void ProcessedInvoke(InvokeType type, int flags) REQUIRES(!stats_lock_) {
STATS_LOCK();
if (flags == 0) {
unresolved_methods_[type]++;
} else {
DCHECK_NE((flags & kFlagMethodResolved), 0);
resolved_methods_[type]++;
if ((flags & kFlagVirtualMadeDirect) != 0) {
virtual_made_direct_[type]++;
if ((flags & kFlagPreciseTypeDevirtualization) != 0) {
type_based_devirtualization_++;
}
} else {
DCHECK_EQ((flags & kFlagPreciseTypeDevirtualization), 0);
}
if ((flags & kFlagDirectCallToBoot) != 0) {
direct_calls_to_boot_[type]++;
}
if ((flags & kFlagDirectMethodToBoot) != 0) {
direct_methods_to_boot_[type]++;
}
}
}
// A check-cast could be eliminated due to verifier type analysis.
void SafeCast() REQUIRES(!stats_lock_) {
STATS_LOCK();
safe_casts_++;
}
// A check-cast couldn't be eliminated due to verifier type analysis.
void NotASafeCast() REQUIRES(!stats_lock_) {
STATS_LOCK();
not_safe_casts_++;
}
private:
Mutex stats_lock_;
size_t types_in_dex_cache_;
size_t types_not_in_dex_cache_;
size_t strings_in_dex_cache_;
size_t strings_not_in_dex_cache_;
size_t resolved_types_;
size_t unresolved_types_;
size_t resolved_instance_fields_;
size_t unresolved_instance_fields_;
size_t resolved_local_static_fields_;
size_t resolved_static_fields_;
size_t unresolved_static_fields_;
// Type based devirtualization for invoke interface and virtual.
size_t type_based_devirtualization_;
size_t resolved_methods_[kMaxInvokeType + 1];
size_t unresolved_methods_[kMaxInvokeType + 1];
size_t virtual_made_direct_[kMaxInvokeType + 1];
size_t direct_calls_to_boot_[kMaxInvokeType + 1];
size_t direct_methods_to_boot_[kMaxInvokeType + 1];
size_t safe_casts_;
size_t not_safe_casts_;
DISALLOW_COPY_AND_ASSIGN(AOTCompilationStats);
};
CompilerDriver::CompilerDriver(
const CompilerOptions* compiler_options,
VerificationResults* verification_results,
DexFileToMethodInlinerMap* method_inliner_map,
Compiler::Kind compiler_kind,
InstructionSet instruction_set,
const InstructionSetFeatures* instruction_set_features,
bool boot_image,
bool app_image,
std::unordered_set<std::string>* image_classes,
std::unordered_set<std::string>* compiled_classes,
std::unordered_set<std::string>* compiled_methods,
size_t thread_count,
bool dump_stats,
bool dump_passes,
CumulativeLogger* timer,
int swap_fd,
const ProfileCompilationInfo* profile_compilation_info)
: compiler_options_(compiler_options),
verification_results_(verification_results),
method_inliner_map_(method_inliner_map),
compiler_(Compiler::Create(this, compiler_kind)),
compiler_kind_(compiler_kind),
instruction_set_(instruction_set),
instruction_set_features_(instruction_set_features),
requires_constructor_barrier_lock_("constructor barrier lock"),
compiled_classes_lock_("compiled classes lock"),
compiled_methods_lock_("compiled method lock"),
compiled_methods_(MethodTable::key_compare()),
non_relative_linker_patch_count_(0u),
boot_image_(boot_image),
app_image_(app_image),
image_classes_(image_classes),
classes_to_compile_(compiled_classes),
methods_to_compile_(compiled_methods),
had_hard_verifier_failure_(false),
parallel_thread_count_(thread_count),
stats_(new AOTCompilationStats),
dump_stats_(dump_stats),
dump_passes_(dump_passes),
timings_logger_(timer),
compiler_context_(nullptr),
support_boot_image_fixup_(instruction_set != kMips && instruction_set != kMips64),
dex_files_for_oat_file_(nullptr),
compiled_method_storage_(swap_fd),
profile_compilation_info_(profile_compilation_info),
max_arena_alloc_(0) {
DCHECK(compiler_options_ != nullptr);
DCHECK(method_inliner_map_ != nullptr);
compiler_->Init();
if (compiler_options->VerifyOnlyProfile()) {
CHECK(profile_compilation_info_ != nullptr) << "Requires profile";
}
if (boot_image_) {
CHECK(image_classes_.get() != nullptr) << "Expected image classes for boot image";
}
}
CompilerDriver::~CompilerDriver() {
Thread* self = Thread::Current();
{
MutexLock mu(self, compiled_classes_lock_);
STLDeleteValues(&compiled_classes_);
}
{
MutexLock mu(self, compiled_methods_lock_);
for (auto& pair : compiled_methods_) {
CompiledMethod::ReleaseSwapAllocatedCompiledMethod(this, pair.second);
}
}
compiler_->UnInit();
}
#define CREATE_TRAMPOLINE(type, abi, offset) \
if (Is64BitInstructionSet(instruction_set_)) { \
return CreateTrampoline64(instruction_set_, abi, \
type ## _ENTRYPOINT_OFFSET(8, offset)); \
} else { \
return CreateTrampoline32(instruction_set_, abi, \
type ## _ENTRYPOINT_OFFSET(4, offset)); \
}
std::unique_ptr<const std::vector<uint8_t>> CompilerDriver::CreateJniDlsymLookup() const {
CREATE_TRAMPOLINE(JNI, kJniAbi, pDlsymLookup)
}
std::unique_ptr<const std::vector<uint8_t>> CompilerDriver::CreateQuickGenericJniTrampoline()
const {
CREATE_TRAMPOLINE(QUICK, kQuickAbi, pQuickGenericJniTrampoline)
}
std::unique_ptr<const std::vector<uint8_t>> CompilerDriver::CreateQuickImtConflictTrampoline()
const {
CREATE_TRAMPOLINE(QUICK, kQuickAbi, pQuickImtConflictTrampoline)
}
std::unique_ptr<const std::vector<uint8_t>> CompilerDriver::CreateQuickResolutionTrampoline()
const {
CREATE_TRAMPOLINE(QUICK, kQuickAbi, pQuickResolutionTrampoline)
}
std::unique_ptr<const std::vector<uint8_t>> CompilerDriver::CreateQuickToInterpreterBridge()
const {
CREATE_TRAMPOLINE(QUICK, kQuickAbi, pQuickToInterpreterBridge)
}
#undef CREATE_TRAMPOLINE
void CompilerDriver::CompileAll(jobject class_loader,
const std::vector<const DexFile*>& dex_files,
TimingLogger* timings) {
DCHECK(!Runtime::Current()->IsStarted());
InitializeThreadPools();
VLOG(compiler) << "Before precompile " << GetMemoryUsageString(false);
// Precompile:
// 1) Load image classes
// 2) Resolve all classes
// 3) Attempt to verify all classes
// 4) Attempt to initialize image classes, and trivially initialized classes
PreCompile(class_loader, dex_files, timings);
// Compile:
// 1) Compile all classes and methods enabled for compilation. May fall back to dex-to-dex
// compilation.
if (!GetCompilerOptions().VerifyAtRuntime()) {
Compile(class_loader, dex_files, timings);
}
if (dump_stats_) {
stats_->Dump();
}
FreeThreadPools();
}
static optimizer::DexToDexCompilationLevel GetDexToDexCompilationLevel(
Thread* self, const CompilerDriver& driver, Handle<mirror::ClassLoader> class_loader,
const DexFile& dex_file, const DexFile::ClassDef& class_def)
SHARED_REQUIRES(Locks::mutator_lock_) {
auto* const runtime = Runtime::Current();
if (runtime->UseJitCompilation() || driver.GetCompilerOptions().VerifyAtRuntime()) {
// Verify at runtime shouldn't dex to dex since we didn't resolve of verify.
return optimizer::DexToDexCompilationLevel::kDontDexToDexCompile;
}
const char* descriptor = dex_file.GetClassDescriptor(class_def);
ClassLinker* class_linker = runtime->GetClassLinker();
mirror::Class* klass = class_linker->FindClass(self, descriptor, class_loader);
if (klass == nullptr) {
CHECK(self->IsExceptionPending());
self->ClearException();
return optimizer::DexToDexCompilationLevel::kDontDexToDexCompile;
}
// DexToDex at the kOptimize level may introduce quickened opcodes, which replace symbolic
// references with actual offsets. We cannot re-verify such instructions.
//
// We store the verification information in the class status in the oat file, which the linker
// can validate (checksums) and use to skip load-time verification. It is thus safe to
// optimize when a class has been fully verified before.
if (klass->IsVerified()) {
// Class is verified so we can enable DEX-to-DEX compilation for performance.
return optimizer::DexToDexCompilationLevel::kOptimize;
} else if (klass->IsCompileTimeVerified()) {
// Class verification has soft-failed. Anyway, ensure at least correctness.
DCHECK_EQ(klass->GetStatus(), mirror::Class::kStatusRetryVerificationAtRuntime);
return optimizer::DexToDexCompilationLevel::kRequired;
} else {
// Class verification has failed: do not run DEX-to-DEX compilation.
return optimizer::DexToDexCompilationLevel::kDontDexToDexCompile;
}
}
static optimizer::DexToDexCompilationLevel GetDexToDexCompilationLevel(
Thread* self,
const CompilerDriver& driver,
jobject jclass_loader,
const DexFile& dex_file,
const DexFile::ClassDef& class_def) {
ScopedObjectAccess soa(self);
StackHandleScope<1> hs(soa.Self());
Handle<mirror::ClassLoader> class_loader(
hs.NewHandle(soa.Decode<mirror::ClassLoader*>(jclass_loader)));
return GetDexToDexCompilationLevel(self, driver, class_loader, dex_file, class_def);
}
// Does the runtime for the InstructionSet provide an implementation returned by
// GetQuickGenericJniStub allowing down calls that aren't compiled using a JNI compiler?
static bool InstructionSetHasGenericJniStub(InstructionSet isa) {
switch (isa) {
case kArm:
case kArm64:
case kThumb2:
case kMips:
case kMips64:
case kX86:
case kX86_64: return true;
default: return false;
}
}
static void CompileMethod(Thread* self,
CompilerDriver* driver,
const DexFile::CodeItem* code_item,
uint32_t access_flags,
InvokeType invoke_type,
uint16_t class_def_idx,
uint32_t method_idx,
jobject class_loader,
const DexFile& dex_file,
optimizer::DexToDexCompilationLevel dex_to_dex_compilation_level,
bool compilation_enabled,
Handle<mirror::DexCache> dex_cache)
REQUIRES(!driver->compiled_methods_lock_) {
DCHECK(driver != nullptr);
CompiledMethod* compiled_method = nullptr;
uint64_t start_ns = kTimeCompileMethod ? NanoTime() : 0;
MethodReference method_ref(&dex_file, method_idx);
if ((access_flags & kAccNative) != 0) {
// Are we extracting only and have support for generic JNI down calls?
if (!driver->GetCompilerOptions().IsJniCompilationEnabled() &&
InstructionSetHasGenericJniStub(driver->GetInstructionSet())) {
// Leaving this empty will trigger the generic JNI version
} else {
compiled_method = driver->GetCompiler()->JniCompile(access_flags, method_idx, dex_file);
CHECK(compiled_method != nullptr);
}
} else if ((access_flags & kAccAbstract) != 0) {
// Abstract methods don't have code.
} else {
const VerifiedMethod* verified_method =
driver->GetVerificationResults()->GetVerifiedMethod(method_ref);
bool compile = compilation_enabled &&
// Basic checks, e.g., not <clinit>.
driver->GetVerificationResults()
->IsCandidateForCompilation(method_ref, access_flags) &&
// Did not fail to create VerifiedMethod metadata.
verified_method != nullptr &&
// Do not have failures that should punt to the interpreter.
!verified_method->HasRuntimeThrow() &&
(verified_method->GetEncounteredVerificationFailures() &
(verifier::VERIFY_ERROR_FORCE_INTERPRETER | verifier::VERIFY_ERROR_LOCKING)) == 0 &&
// Is eligable for compilation by methods-to-compile filter.
driver->IsMethodToCompile(method_ref) &&
driver->ShouldCompileBasedOnProfile(method_ref);
if (compile) {
// NOTE: if compiler declines to compile this method, it will return null.
compiled_method = driver->GetCompiler()->Compile(code_item, access_flags, invoke_type,
class_def_idx, method_idx, class_loader,
dex_file, dex_cache);
}
if (compiled_method == nullptr &&
dex_to_dex_compilation_level != optimizer::DexToDexCompilationLevel::kDontDexToDexCompile) {
// TODO: add a command-line option to disable DEX-to-DEX compilation ?
// Do not optimize if a VerifiedMethod is missing. SafeCast elision, for example, relies on
// it.
compiled_method = optimizer::ArtCompileDEX(
driver,
code_item,
access_flags,
invoke_type,
class_def_idx,
method_idx,
class_loader,
dex_file,
(verified_method != nullptr)
? dex_to_dex_compilation_level
: optimizer::DexToDexCompilationLevel::kRequired);
}
}
if (kTimeCompileMethod) {
uint64_t duration_ns = NanoTime() - start_ns;
if (duration_ns > MsToNs(driver->GetCompiler()->GetMaximumCompilationTimeBeforeWarning())) {
LOG(WARNING) << "Compilation of " << PrettyMethod(method_idx, dex_file)
<< " took " << PrettyDuration(duration_ns);
}
}
if (compiled_method != nullptr) {
// Count non-relative linker patches.
size_t non_relative_linker_patch_count = 0u;
for (const LinkerPatch& patch : compiled_method->GetPatches()) {
if (!patch.IsPcRelative()) {
++non_relative_linker_patch_count;
}
}
bool compile_pic = driver->GetCompilerOptions().GetCompilePic(); // Off by default
// When compiling with PIC, there should be zero non-relative linker patches
CHECK(!compile_pic || non_relative_linker_patch_count == 0u);
driver->AddCompiledMethod(method_ref, compiled_method, non_relative_linker_patch_count);
}
// Done compiling, delete the verified method to reduce native memory usage. Do not delete in
// optimizing compiler, which may need the verified method again for inlining.
if (driver->GetCompilerKind() != Compiler::kOptimizing) {
driver->GetVerificationResults()->RemoveVerifiedMethod(method_ref);
}
if (self->IsExceptionPending()) {
ScopedObjectAccess soa(self);
LOG(FATAL) << "Unexpected exception compiling: " << PrettyMethod(method_idx, dex_file) << "\n"
<< self->GetException()->Dump();
}
}
void CompilerDriver::CompileOne(Thread* self, ArtMethod* method, TimingLogger* timings) {
DCHECK(!Runtime::Current()->IsStarted());
jobject jclass_loader;
const DexFile* dex_file;
uint16_t class_def_idx;
uint32_t method_idx = method->GetDexMethodIndex();
uint32_t access_flags = method->GetAccessFlags();
InvokeType invoke_type = method->GetInvokeType();
StackHandleScope<1> hs(self);
Handle<mirror::DexCache> dex_cache(hs.NewHandle(method->GetDexCache()));
{
ScopedObjectAccessUnchecked soa(self);
ScopedLocalRef<jobject> local_class_loader(
soa.Env(), soa.AddLocalReference<jobject>(method->GetDeclaringClass()->GetClassLoader()));
jclass_loader = soa.Env()->NewGlobalRef(local_class_loader.get());
// Find the dex_file
dex_file = method->GetDexFile();
class_def_idx = method->GetClassDefIndex();
}
const DexFile::CodeItem* code_item = dex_file->GetCodeItem(method->GetCodeItemOffset());
// Go to native so that we don't block GC during compilation.
ScopedThreadSuspension sts(self, kNative);
std::vector<const DexFile*> dex_files;
dex_files.push_back(dex_file);
InitializeThreadPools();
PreCompile(jclass_loader, dex_files, timings);
// Can we run DEX-to-DEX compiler on this class ?
optimizer::DexToDexCompilationLevel dex_to_dex_compilation_level =
GetDexToDexCompilationLevel(self,
*this,
jclass_loader,
*dex_file,
dex_file->GetClassDef(class_def_idx));
CompileMethod(self,
this,
code_item,
access_flags,
invoke_type,
class_def_idx,
method_idx,
jclass_loader,
*dex_file,
dex_to_dex_compilation_level,
true,
dex_cache);
FreeThreadPools();
self->GetJniEnv()->DeleteGlobalRef(jclass_loader);
}
void CompilerDriver::Resolve(jobject class_loader,
const std::vector<const DexFile*>& dex_files,
TimingLogger* timings) {
// Resolution allocates classes and needs to run single-threaded to be deterministic.
bool force_determinism = GetCompilerOptions().IsForceDeterminism();
ThreadPool* resolve_thread_pool = force_determinism
? single_thread_pool_.get()
: parallel_thread_pool_.get();
size_t resolve_thread_count = force_determinism ? 1U : parallel_thread_count_;
for (size_t i = 0; i != dex_files.size(); ++i) {
const DexFile* dex_file = dex_files[i];
CHECK(dex_file != nullptr);
ResolveDexFile(class_loader,
*dex_file,
dex_files,
resolve_thread_pool,
resolve_thread_count,
timings);
}
}
// Resolve const-strings in the code. Done to have deterministic allocation behavior. Right now
// this is single-threaded for simplicity.
// TODO: Collect the relevant string indices in parallel, then allocate them sequentially in a
// stable order.
static void ResolveConstStrings(CompilerDriver* driver,
const DexFile& dex_file,
const DexFile::CodeItem* code_item) {
if (code_item == nullptr) {
// Abstract or native method.
return;
}
const uint16_t* code_ptr = code_item->insns_;
const uint16_t* code_end = code_item->insns_ + code_item->insns_size_in_code_units_;
while (code_ptr < code_end) {
const Instruction* inst = Instruction::At(code_ptr);
switch (inst->Opcode()) {
case Instruction::CONST_STRING: {
uint32_t string_index = inst->VRegB_21c();
driver->CanAssumeStringIsPresentInDexCache(dex_file, string_index);
break;
}
case Instruction::CONST_STRING_JUMBO: {
uint32_t string_index = inst->VRegB_31c();
driver->CanAssumeStringIsPresentInDexCache(dex_file, string_index);
break;
}
default:
break;
}
code_ptr += inst->SizeInCodeUnits();
}
}
static void ResolveConstStrings(CompilerDriver* driver,
const std::vector<const DexFile*>& dex_files,
TimingLogger* timings) {
for (const DexFile* dex_file : dex_files) {
TimingLogger::ScopedTiming t("Resolve const-string Strings", timings);
size_t class_def_count = dex_file->NumClassDefs();
for (size_t class_def_index = 0; class_def_index < class_def_count; ++class_def_index) {
const DexFile::ClassDef& class_def = dex_file->GetClassDef(class_def_index);
const uint8_t* class_data = dex_file->GetClassData(class_def);
if (class_data == nullptr) {
// empty class, probably a marker interface
continue;
}
ClassDataItemIterator it(*dex_file, class_data);
// Skip fields
while (it.HasNextStaticField()) {
it.Next();
}
while (it.HasNextInstanceField()) {
it.Next();
}
bool compilation_enabled = driver->IsClassToCompile(
dex_file->StringByTypeIdx(class_def.class_idx_));
if (!compilation_enabled) {
// Compilation is skipped, do not resolve const-string in code of this class.
// TODO: Make sure that inlining honors this.
continue;
}
// Direct methods.
int64_t previous_direct_method_idx = -1;
while (it.HasNextDirectMethod()) {
uint32_t method_idx = it.GetMemberIndex();
if (method_idx == previous_direct_method_idx) {
// smali can create dex files with two encoded_methods sharing the same method_idx
// http://code.google.com/p/smali/issues/detail?id=119
it.Next();
continue;
}
previous_direct_method_idx = method_idx;
ResolveConstStrings(driver, *dex_file, it.GetMethodCodeItem());
it.Next();
}
// Virtual methods.
int64_t previous_virtual_method_idx = -1;
while (it.HasNextVirtualMethod()) {
uint32_t method_idx = it.GetMemberIndex();
if (method_idx == previous_virtual_method_idx) {
// smali can create dex files with two encoded_methods sharing the same method_idx
// http://code.google.com/p/smali/issues/detail?id=119
it.Next();
continue;
}
previous_virtual_method_idx = method_idx;
ResolveConstStrings(driver, *dex_file, it.GetMethodCodeItem());
it.Next();
}
DCHECK(!it.HasNext());
}
}
}
inline void CompilerDriver::CheckThreadPools() {
DCHECK(parallel_thread_pool_ != nullptr);
DCHECK(single_thread_pool_ != nullptr);
}
void CompilerDriver::PreCompile(jobject class_loader,
const std::vector<const DexFile*>& dex_files,
TimingLogger* timings) {
CheckThreadPools();
LoadImageClasses(timings);
VLOG(compiler) << "LoadImageClasses: " << GetMemoryUsageString(false);
const bool verification_enabled = compiler_options_->IsVerificationEnabled();
const bool never_verify = compiler_options_->NeverVerify();
const bool verify_only_profile = compiler_options_->VerifyOnlyProfile();
// We need to resolve for never_verify since it needs to run dex to dex to add the
// RETURN_VOID_NO_BARRIER.
// Let the verifier resolve as needed for the verify_only_profile case.
if ((never_verify || verification_enabled) && !verify_only_profile) {
Resolve(class_loader, dex_files, timings);
VLOG(compiler) << "Resolve: " << GetMemoryUsageString(false);
}
if (never_verify) {
VLOG(compiler) << "Verify none mode specified, skipping verification.";
SetVerified(class_loader, dex_files, timings);
}
if (!verification_enabled) {
return;
}
if (GetCompilerOptions().IsForceDeterminism() && IsBootImage()) {
// Resolve strings from const-string. Do this now to have a deterministic image.
ResolveConstStrings(this, dex_files, timings);
VLOG(compiler) << "Resolve const-strings: " << GetMemoryUsageString(false);
}
Verify(class_loader, dex_files, timings);
VLOG(compiler) << "Verify: " << GetMemoryUsageString(false);
if (had_hard_verifier_failure_ && GetCompilerOptions().AbortOnHardVerifierFailure()) {
LOG(FATAL) << "Had a hard failure verifying all classes, and was asked to abort in such "
<< "situations. Please check the log.";
}
InitializeClasses(class_loader, dex_files, timings);
VLOG(compiler) << "InitializeClasses: " << GetMemoryUsageString(false);
UpdateImageClasses(timings);
VLOG(compiler) << "UpdateImageClasses: " << GetMemoryUsageString(false);
}
bool CompilerDriver::IsImageClass(const char* descriptor) const {
if (image_classes_ != nullptr) {
// If we have a set of image classes, use those.
return image_classes_->find(descriptor) != image_classes_->end();
}
// No set of image classes, assume we include all the classes.
// NOTE: Currently only reachable from InitImageMethodVisitor for the app image case.
return !IsBootImage();
}
bool CompilerDriver::IsClassToCompile(const char* descriptor) const {
if (kRestrictCompilationFiltersToImage && !IsBootImage()) {
return true;
}
if (classes_to_compile_ == nullptr) {
return true;
}
return classes_to_compile_->find(descriptor) != classes_to_compile_->end();
}
bool CompilerDriver::IsMethodToCompile(const MethodReference& method_ref) const {
if (kRestrictCompilationFiltersToImage && !IsBootImage()) {
return true;
}
if (methods_to_compile_ == nullptr) {
return true;
}
std::string tmp = PrettyMethod(method_ref.dex_method_index, *method_ref.dex_file, true);
return methods_to_compile_->find(tmp.c_str()) != methods_to_compile_->end();
}
bool CompilerDriver::ShouldCompileBasedOnProfile(const MethodReference& method_ref) const {
if (profile_compilation_info_ == nullptr) {
// If we miss profile information it means that we don't do a profile guided compilation.
// Return true, and let the other filters decide if the method should be compiled.
return true;
}
bool result = profile_compilation_info_->ContainsMethod(method_ref);
if (kDebugProfileGuidedCompilation) {
LOG(INFO) << "[ProfileGuidedCompilation] "
<< (result ? "Compiled" : "Skipped") << " method:"
<< PrettyMethod(method_ref.dex_method_index, *method_ref.dex_file, true);
}
return result;
}
bool CompilerDriver::ShouldVerifyClassBasedOnProfile(const DexFile& dex_file,
uint16_t class_idx) const {
if (!compiler_options_->VerifyOnlyProfile()) {
// No profile, verify everything.
return true;
}
DCHECK(profile_compilation_info_ != nullptr);
bool result = profile_compilation_info_->ContainsClass(dex_file, class_idx);
if (kDebugProfileGuidedCompilation) {
LOG(INFO) << "[ProfileGuidedCompilation] "
<< (result ? "Verified" : "Skipped") << " method:"
<< dex_file.GetClassDescriptor(dex_file.GetClassDef(class_idx));
}
return result;
}
class ResolveCatchBlockExceptionsClassVisitor : public ClassVisitor {
public:
explicit ResolveCatchBlockExceptionsClassVisitor(
std::set<std::pair<uint16_t, const DexFile*>>& exceptions_to_resolve)
: exceptions_to_resolve_(exceptions_to_resolve) {}
virtual bool operator()(mirror::Class* c) OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
const auto pointer_size = Runtime::Current()->GetClassLinker()->GetImagePointerSize();
for (auto& m : c->GetMethods(pointer_size)) {
ResolveExceptionsForMethod(&m, pointer_size);
}
return true;
}
private:
void ResolveExceptionsForMethod(ArtMethod* method_handle, size_t pointer_size)
SHARED_REQUIRES(Locks::mutator_lock_) {
const DexFile::CodeItem* code_item = method_handle->GetCodeItem();
if (code_item == nullptr) {
return; // native or abstract method
}
if (code_item->tries_size_ == 0) {
return; // nothing to process
}
const uint8_t* encoded_catch_handler_list = DexFile::GetCatchHandlerData(*code_item, 0);
size_t num_encoded_catch_handlers = DecodeUnsignedLeb128(&encoded_catch_handler_list);
for (size_t i = 0; i < num_encoded_catch_handlers; i++) {
int32_t encoded_catch_handler_size = DecodeSignedLeb128(&encoded_catch_handler_list);
bool has_catch_all = false;
if (encoded_catch_handler_size <= 0) {
encoded_catch_handler_size = -encoded_catch_handler_size;
has_catch_all = true;
}
for (int32_t j = 0; j < encoded_catch_handler_size; j++) {
uint16_t encoded_catch_handler_handlers_type_idx =
DecodeUnsignedLeb128(&encoded_catch_handler_list);
// Add to set of types to resolve if not already in the dex cache resolved types
if (!method_handle->IsResolvedTypeIdx(encoded_catch_handler_handlers_type_idx,
pointer_size)) {
exceptions_to_resolve_.emplace(encoded_catch_handler_handlers_type_idx,
method_handle->GetDexFile());
}
// ignore address associated with catch handler
DecodeUnsignedLeb128(&encoded_catch_handler_list);
}
if (has_catch_all) {
// ignore catch all address
DecodeUnsignedLeb128(&encoded_catch_handler_list);
}
}
}
std::set<std::pair<uint16_t, const DexFile*>>& exceptions_to_resolve_;
};
class RecordImageClassesVisitor : public ClassVisitor {
public:
explicit RecordImageClassesVisitor(std::unordered_set<std::string>* image_classes)
: image_classes_(image_classes) {}
bool operator()(mirror::Class* klass) OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
std::string temp;
image_classes_->insert(klass->GetDescriptor(&temp));
return true;
}
private:
std::unordered_set<std::string>* const image_classes_;
};
// Make a list of descriptors for classes to include in the image
void CompilerDriver::LoadImageClasses(TimingLogger* timings) {
CHECK(timings != nullptr);
if (!IsBootImage()) {
return;
}
TimingLogger::ScopedTiming t("LoadImageClasses", timings);
// Make a first class to load all classes explicitly listed in the file
Thread* self = Thread::Current();
ScopedObjectAccess soa(self);
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
CHECK(image_classes_.get() != nullptr);
for (auto it = image_classes_->begin(), end = image_classes_->end(); it != end;) {
const std::string& descriptor(*it);
StackHandleScope<1> hs(self);
Handle<mirror::Class> klass(
hs.NewHandle(class_linker->FindSystemClass(self, descriptor.c_str())));
if (klass.Get() == nullptr) {
VLOG(compiler) << "Failed to find class " << descriptor;
image_classes_->erase(it++);
self->ClearException();
} else {
++it;
}
}
// Resolve exception classes referenced by the loaded classes. The catch logic assumes
// exceptions are resolved by the verifier when there is a catch block in an interested method.
// Do this here so that exception classes appear to have been specified image classes.
std::set<std::pair<uint16_t, const DexFile*>> unresolved_exception_types;
StackHandleScope<1> hs(self);
Handle<mirror::Class> java_lang_Throwable(
hs.NewHandle(class_linker->FindSystemClass(self, "Ljava/lang/Throwable;")));
do {
unresolved_exception_types.clear();
ResolveCatchBlockExceptionsClassVisitor visitor(unresolved_exception_types);
class_linker->VisitClasses(&visitor);
for (const std::pair<uint16_t, const DexFile*>& exception_type : unresolved_exception_types) {
uint16_t exception_type_idx = exception_type.first;
const DexFile* dex_file = exception_type.second;
StackHandleScope<2> hs2(self);
Handle<mirror::DexCache> dex_cache(hs2.NewHandle(class_linker->RegisterDexFile(
*dex_file,
Runtime::Current()->GetLinearAlloc())));
Handle<mirror::Class> klass(hs2.NewHandle(
class_linker->ResolveType(*dex_file,
exception_type_idx,
dex_cache,
ScopedNullHandle<mirror::ClassLoader>())));
if (klass.Get() == nullptr) {
const DexFile::TypeId& type_id = dex_file->GetTypeId(exception_type_idx);
const char* descriptor = dex_file->GetTypeDescriptor(type_id);
LOG(FATAL) << "Failed to resolve class " << descriptor;
}
DCHECK(java_lang_Throwable->IsAssignableFrom(klass.Get()));
}
// Resolving exceptions may load classes that reference more exceptions, iterate until no
// more are found
} while (!unresolved_exception_types.empty());
// We walk the roots looking for classes so that we'll pick up the
// above classes plus any classes them depend on such super
// classes, interfaces, and the required ClassLinker roots.
RecordImageClassesVisitor visitor(image_classes_.get());
class_linker->VisitClasses(&visitor);
CHECK_NE(image_classes_->size(), 0U);
}
static void MaybeAddToImageClasses(Handle<mirror::Class> c,
std::unordered_set<std::string>* image_classes)
SHARED_REQUIRES(Locks::mutator_lock_) {
Thread* self = Thread::Current();
StackHandleScope<1> hs(self);
// Make a copy of the handle so that we don't clobber it doing Assign.
MutableHandle<mirror::Class> klass(hs.NewHandle(c.Get()));
std::string temp;
const size_t pointer_size = Runtime::Current()->GetClassLinker()->GetImagePointerSize();
while (!klass->IsObjectClass()) {
const char* descriptor = klass->GetDescriptor(&temp);
std::pair<std::unordered_set<std::string>::iterator, bool> result =
image_classes->insert(descriptor);
if (!result.second) { // Previously inserted.
break;
}
VLOG(compiler) << "Adding " << descriptor << " to image classes";
for (size_t i = 0; i < klass->NumDirectInterfaces(); ++i) {
StackHandleScope<1> hs2(self);
MaybeAddToImageClasses(hs2.NewHandle(mirror::Class::GetDirectInterface(self, klass, i)),
image_classes);
}
for (auto& m : c->GetVirtualMethods(pointer_size)) {
StackHandleScope<1> hs2(self);
MaybeAddToImageClasses(hs2.NewHandle(m.GetDeclaringClass()), image_classes);
}
if (klass->IsArrayClass()) {
StackHandleScope<1> hs2(self);
MaybeAddToImageClasses(hs2.NewHandle(klass->GetComponentType()), image_classes);
}
klass.Assign(klass->GetSuperClass());
}
}
// Keeps all the data for the update together. Also doubles as the reference visitor.
// Note: we can use object pointers because we suspend all threads.
class ClinitImageUpdate {
public:
static ClinitImageUpdate* Create(std::unordered_set<std::string>* image_class_descriptors,
Thread* self, ClassLinker* linker, std::string* error_msg) {
std::unique_ptr<ClinitImageUpdate> res(new ClinitImageUpdate(image_class_descriptors, self,
linker));
if (res->dex_cache_class_ == nullptr) {
*error_msg = "Could not find DexCache class.";
return nullptr;
}
return res.release();
}
~ClinitImageUpdate() {
// Allow others to suspend again.
self_->EndAssertNoThreadSuspension(old_cause_);
}
// Visitor for VisitReferences.
void operator()(mirror::Object* object, MemberOffset field_offset, bool /* is_static */) const
SHARED_REQUIRES(Locks::mutator_lock_) {
mirror::Object* ref = object->GetFieldObject<mirror::Object>(field_offset);
if (ref != nullptr) {
VisitClinitClassesObject(ref);
}
}
// java.lang.Reference visitor for VisitReferences.
void operator()(mirror::Class* klass ATTRIBUTE_UNUSED, mirror::Reference* ref ATTRIBUTE_UNUSED)
const {}
// Ignore class native roots.
void VisitRootIfNonNull(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED)
const {}
void VisitRoot(mirror::CompressedReference<mirror::Object>* root ATTRIBUTE_UNUSED) const {}
void Walk() SHARED_REQUIRES(Locks::mutator_lock_) {
// Use the initial classes as roots for a search.
for (mirror::Class* klass_root : image_classes_) {
VisitClinitClassesObject(klass_root);
}
}
private:
class FindImageClassesVisitor : public ClassVisitor {
public:
explicit FindImageClassesVisitor(ClinitImageUpdate* data) : data_(data) {}
bool operator()(mirror::Class* klass) OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
std::string temp;
const char* name = klass->GetDescriptor(&temp);
if (data_->image_class_descriptors_->find(name) != data_->image_class_descriptors_->end()) {
data_->image_classes_.push_back(klass);
} else {
// Check whether it is initialized and has a clinit. They must be kept, too.
if (klass->IsInitialized() && klass->FindClassInitializer(
Runtime::Current()->GetClassLinker()->GetImagePointerSize()) != nullptr) {
data_->image_classes_.push_back(klass);
}
}
return true;
}
private:
ClinitImageUpdate* const data_;
};
ClinitImageUpdate(std::unordered_set<std::string>* image_class_descriptors, Thread* self,
ClassLinker* linker)
SHARED_REQUIRES(Locks::mutator_lock_) :
image_class_descriptors_(image_class_descriptors), self_(self) {
CHECK(linker != nullptr);
CHECK(image_class_descriptors != nullptr);
// Make sure nobody interferes with us.
old_cause_ = self->StartAssertNoThreadSuspension("Boot image closure");
// Find the interesting classes.
dex_cache_class_ = linker->LookupClass(self, "Ljava/lang/DexCache;",
ComputeModifiedUtf8Hash("Ljava/lang/DexCache;"), nullptr);
// Find all the already-marked classes.
WriterMutexLock mu(self, *Locks::heap_bitmap_lock_);
FindImageClassesVisitor visitor(this);
linker->VisitClasses(&visitor);
}
void VisitClinitClassesObject(mirror::Object* object) const
SHARED_REQUIRES(Locks::mutator_lock_) {
DCHECK(object != nullptr);
if (marked_objects_.find(object) != marked_objects_.end()) {
// Already processed.
return;
}
// Mark it.
marked_objects_.insert(object);
if (object->IsClass()) {
// If it is a class, add it.
StackHandleScope<1> hs(self_);
MaybeAddToImageClasses(hs.NewHandle(object->AsClass()), image_class_descriptors_);
} else {
// Else visit the object's class.
VisitClinitClassesObject(object->GetClass());
}
// If it is not a DexCache, visit all references.
mirror::Class* klass = object->GetClass();
if (klass != dex_cache_class_) {
object->VisitReferences(*this, *this);
}
}
mutable std::unordered_set<mirror::Object*> marked_objects_;
std::unordered_set<std::string>* const image_class_descriptors_;
std::vector<mirror::Class*> image_classes_;
const mirror::Class* dex_cache_class_;
Thread* const self_;
const char* old_cause_;
DISALLOW_COPY_AND_ASSIGN(ClinitImageUpdate);
};
void CompilerDriver::UpdateImageClasses(TimingLogger* timings) {
if (IsBootImage()) {
TimingLogger::ScopedTiming t("UpdateImageClasses", timings);
Runtime* runtime = Runtime::Current();
// Suspend all threads.
ScopedSuspendAll ssa(__FUNCTION__);
std::string error_msg;
std::unique_ptr<ClinitImageUpdate> update(ClinitImageUpdate::Create(image_classes_.get(),
Thread::Current(),
runtime->GetClassLinker(),
&error_msg));
CHECK(update.get() != nullptr) << error_msg; // TODO: Soft failure?
// Do the marking.
update->Walk();
}
}
bool CompilerDriver::CanAssumeClassIsLoaded(mirror::Class* klass) {
Runtime* runtime = Runtime::Current();
if (!runtime->IsAotCompiler()) {
DCHECK(runtime->UseJitCompilation());
// Having the klass reference here implies that the klass is already loaded.
return true;
}
if (!IsBootImage()) {
// Assume loaded only if klass is in the boot image. App classes cannot be assumed
// loaded because we don't even know what class loader will be used to load them.
bool class_in_image = runtime->GetHeap()->FindSpaceFromObject(klass, false)->IsImageSpace();
return class_in_image;
}
std::string temp;
const char* descriptor = klass->GetDescriptor(&temp);
return IsImageClass(descriptor);
}
bool CompilerDriver::CanAssumeTypeIsPresentInDexCache(Handle<mirror::DexCache> dex_cache,
uint32_t type_idx) {
bool result = false;
if ((IsBootImage() &&
IsImageClass(dex_cache->GetDexFile()->StringDataByIdx(
dex_cache->GetDexFile()->GetTypeId(type_idx).descriptor_idx_))) ||
Runtime::Current()->UseJitCompilation()) {
mirror::Class* resolved_class = dex_cache->GetResolvedType(type_idx);
result = (resolved_class != nullptr);
}
if (result) {
stats_->TypeInDexCache();
} else {
stats_->TypeNotInDexCache();
}
return result;
}
bool CompilerDriver::CanAssumeStringIsPresentInDexCache(const DexFile& dex_file,
uint32_t string_idx) {
// See also Compiler::ResolveDexFile
bool result = false;
if (IsBootImage() || Runtime::Current()->UseJitCompilation()) {
ScopedObjectAccess soa(Thread::Current());
StackHandleScope<1> hs(soa.Self());
ClassLinker* const class_linker = Runtime::Current()->GetClassLinker();
Handle<mirror::DexCache> dex_cache(hs.NewHandle(class_linker->FindDexCache(
soa.Self(), dex_file, false)));
if (IsBootImage()) {
// We resolve all const-string strings when building for the image.
class_linker->ResolveString(dex_file, string_idx, dex_cache);
result = true;
} else {
// Just check whether the dex cache already has the string.
DCHECK(Runtime::Current()->UseJitCompilation());
result = (dex_cache->GetResolvedString(string_idx) != nullptr);
}
}
if (result) {
stats_->StringInDexCache();
} else {
stats_->StringNotInDexCache();
}
return result;
}
bool CompilerDriver::CanAccessTypeWithoutChecks(uint32_t referrer_idx,
Handle<mirror::DexCache> dex_cache,
uint32_t type_idx) {
// Get type from dex cache assuming it was populated by the verifier
mirror::Class* resolved_class = dex_cache->GetResolvedType(type_idx);
if (resolved_class == nullptr) {
stats_->TypeNeedsAccessCheck();
return false; // Unknown class needs access checks.
}
const DexFile::MethodId& method_id = dex_cache->GetDexFile()->GetMethodId(referrer_idx);
bool is_accessible = resolved_class->IsPublic(); // Public classes are always accessible.
if (!is_accessible) {
mirror::Class* referrer_class = dex_cache->GetResolvedType(method_id.class_idx_);
if (referrer_class == nullptr) {
stats_->TypeNeedsAccessCheck();
return false; // Incomplete referrer knowledge needs access check.
}
// Perform access check, will return true if access is ok or false if we're going to have to
// check this at runtime (for example for class loaders).
is_accessible = referrer_class->CanAccess(resolved_class);
}
if (is_accessible) {
stats_->TypeDoesntNeedAccessCheck();
} else {
stats_->TypeNeedsAccessCheck();
}
return is_accessible;
}
bool CompilerDriver::CanAccessInstantiableTypeWithoutChecks(uint32_t referrer_idx,
Handle<mirror::DexCache> dex_cache,
uint32_t type_idx,
bool* finalizable) {
// Get type from dex cache assuming it was populated by the verifier.
mirror::Class* resolved_class = dex_cache->GetResolvedType(type_idx);
if (resolved_class == nullptr) {
stats_->TypeNeedsAccessCheck();
// Be conservative.
*finalizable = true;
return false; // Unknown class needs access checks.
}
*finalizable = resolved_class->IsFinalizable();
const DexFile::MethodId& method_id = dex_cache->GetDexFile()->GetMethodId(referrer_idx);
bool is_accessible = resolved_class->IsPublic(); // Public classes are always accessible.
if (!is_accessible) {
mirror::Class* referrer_class = dex_cache->GetResolvedType(method_id.class_idx_);
if (referrer_class == nullptr) {
stats_->TypeNeedsAccessCheck();
return false; // Incomplete referrer knowledge needs access check.
}
// Perform access and instantiable checks, will return true if access is ok or false if we're
// going to have to check this at runtime (for example for class loaders).
is_accessible = referrer_class->CanAccess(resolved_class);
}
bool result = is_accessible && resolved_class->IsInstantiable();
if (result) {
stats_->TypeDoesntNeedAccessCheck();
} else {
stats_->TypeNeedsAccessCheck();
}
return result;
}
bool CompilerDriver::CanEmbedTypeInCode(const DexFile& dex_file, uint32_t type_idx,
bool* is_type_initialized, bool* use_direct_type_ptr,
uintptr_t* direct_type_ptr, bool* out_is_finalizable) {
ScopedObjectAccess soa(Thread::Current());
Runtime* runtime = Runtime::Current();
mirror::DexCache* dex_cache = runtime->GetClassLinker()->FindDexCache(
soa.Self(), dex_file, false);
mirror::Class* resolved_class = dex_cache->GetResolvedType(type_idx);
if (resolved_class == nullptr) {
return false;
}
if (GetCompilerOptions().GetCompilePic()) {
// Do not allow a direct class pointer to be used when compiling for position-independent
return false;
}
*out_is_finalizable = resolved_class->IsFinalizable();
gc::Heap* heap = runtime->GetHeap();
const bool compiling_boot = heap->IsCompilingBoot();
const bool support_boot_image_fixup = GetSupportBootImageFixup();
if (compiling_boot) {
// boot -> boot class pointers.
// True if the class is in the image at boot compiling time.
const bool is_image_class = IsBootImage() && IsImageClass(
dex_file.StringDataByIdx(dex_file.GetTypeId(type_idx).descriptor_idx_));
// True if pc relative load works.
if (is_image_class && support_boot_image_fixup) {
*is_type_initialized = resolved_class->IsInitialized();
*use_direct_type_ptr = false;
*direct_type_ptr = 0;
return true;
} else {
return false;
}
} else if (runtime->UseJitCompilation() && !heap->IsMovableObject(resolved_class)) {
*is_type_initialized = resolved_class->IsInitialized();
// If the class may move around, then don't embed it as a direct pointer.
*use_direct_type_ptr = true;
*direct_type_ptr = reinterpret_cast<uintptr_t>(resolved_class);
return true;
} else {
// True if the class is in the image at app compiling time.
const bool class_in_image = heap->FindSpaceFromObject(resolved_class, false)->IsImageSpace();
if (class_in_image && support_boot_image_fixup) {
// boot -> app class pointers.
*is_type_initialized = resolved_class->IsInitialized();
// TODO This is somewhat hacky. We should refactor all of this invoke codepath.
*use_direct_type_ptr = !GetCompilerOptions().GetIncludePatchInformation();
*direct_type_ptr = reinterpret_cast<uintptr_t>(resolved_class);
return true;
} else {
// app -> app class pointers.
// Give up because app does not have an image and class
// isn't created at compile time. TODO: implement this
// if/when each app gets an image.
return false;
}
}
}
bool CompilerDriver::CanEmbedReferenceTypeInCode(ClassReference* ref,
bool* use_direct_ptr,
uintptr_t* direct_type_ptr) {
CHECK(ref != nullptr);
CHECK(use_direct_ptr != nullptr);
CHECK(direct_type_ptr != nullptr);
ScopedObjectAccess soa(Thread::Current());
mirror::Class* reference_class = mirror::Reference::GetJavaLangRefReference();
bool is_initialized = false;
bool unused_finalizable;
// Make sure we have a finished Reference class object before attempting to use it.
if (!CanEmbedTypeInCode(*reference_class->GetDexCache()->GetDexFile(),
reference_class->GetDexTypeIndex(), &is_initialized,
use_direct_ptr, direct_type_ptr, &unused_finalizable) ||
!is_initialized) {
return false;
}
ref->first = &reference_class->GetDexFile();
ref->second = reference_class->GetDexClassDefIndex();
return true;
}
uint32_t CompilerDriver::GetReferenceSlowFlagOffset() const {
ScopedObjectAccess soa(Thread::Current());
mirror::Class* klass = mirror::Reference::GetJavaLangRefReference();
DCHECK(klass->IsInitialized());
return klass->GetSlowPathFlagOffset().Uint32Value();
}
uint32_t CompilerDriver::GetReferenceDisableFlagOffset() const {
ScopedObjectAccess soa(Thread::Current());
mirror::Class* klass = mirror::Reference::GetJavaLangRefReference();
DCHECK(klass->IsInitialized());
return klass->GetDisableIntrinsicFlagOffset().Uint32Value();
}
DexCacheArraysLayout CompilerDriver::GetDexCacheArraysLayout(const DexFile* dex_file) {
return ContainsElement(GetDexFilesForOatFile(), dex_file)
? DexCacheArraysLayout(GetInstructionSetPointerSize(instruction_set_), dex_file)
: DexCacheArraysLayout();
}
void CompilerDriver::ProcessedInstanceField(bool resolved) {
if (!resolved) {
stats_->UnresolvedInstanceField();
} else {
stats_->ResolvedInstanceField();
}
}
void CompilerDriver::ProcessedStaticField(bool resolved, bool local) {
if (!resolved) {
stats_->UnresolvedStaticField();
} else if (local) {
stats_->ResolvedLocalStaticField();
} else {
stats_->ResolvedStaticField();
}
}
void CompilerDriver::ProcessedInvoke(InvokeType invoke_type, int flags) {
stats_->ProcessedInvoke(invoke_type, flags);
}
ArtField* CompilerDriver::ComputeInstanceFieldInfo(uint32_t field_idx,
const DexCompilationUnit* mUnit, bool is_put,
const ScopedObjectAccess& soa) {
// Try to resolve the field and compiling method's class.
ArtField* resolved_field;
mirror::Class* referrer_class;
Handle<mirror::DexCache> dex_cache(mUnit->GetDexCache());
{
StackHandleScope<1> hs(soa.Self());
Handle<mirror::ClassLoader> class_loader_handle(
hs.NewHandle(soa.Decode<mirror::ClassLoader*>(mUnit->GetClassLoader())));
resolved_field = ResolveField(soa, dex_cache, class_loader_handle, mUnit, field_idx, false);
referrer_class = resolved_field != nullptr
? ResolveCompilingMethodsClass(soa, dex_cache, class_loader_handle, mUnit) : nullptr;
}
bool can_link = false;
if (resolved_field != nullptr && referrer_class != nullptr) {
std::pair<bool, bool> fast_path = IsFastInstanceField(
dex_cache.Get(), referrer_class, resolved_field, field_idx);
can_link = is_put ? fast_path.second : fast_path.first;
}
ProcessedInstanceField(can_link);
return can_link ? resolved_field : nullptr;
}
bool CompilerDriver::ComputeInstanceFieldInfo(uint32_t field_idx, const DexCompilationUnit* mUnit,
bool is_put, MemberOffset* field_offset,
bool* is_volatile) {
ScopedObjectAccess soa(Thread::Current());
ArtField* resolved_field = ComputeInstanceFieldInfo(field_idx, mUnit, is_put, soa);
if (resolved_field == nullptr) {
// Conservative defaults.
*is_volatile = true;
*field_offset = MemberOffset(static_cast<size_t>(-1));
return false;
} else {
*is_volatile = resolved_field->IsVolatile();
*field_offset = resolved_field->GetOffset();
return true;
}
}
void CompilerDriver::GetCodeAndMethodForDirectCall(InvokeType* type, InvokeType sharp_type,
bool no_guarantee_of_dex_cache_entry,
const mirror::Class* referrer_class,
ArtMethod* method,
int* stats_flags,
MethodReference* target_method,
uintptr_t* direct_code,
uintptr_t* direct_method) {
// For direct and static methods compute possible direct_code and direct_method values, ie
// an address for the Method* being invoked and an address of the code for that Method*.
// For interface calls compute a value for direct_method that is the interface method being
// invoked, so this can be passed to the out-of-line runtime support code.
*direct_code = 0;
*direct_method = 0;
Runtime* const runtime = Runtime::Current();
gc::Heap* const heap = runtime->GetHeap();
auto* cl = runtime->GetClassLinker();
const auto pointer_size = cl->GetImagePointerSize();
bool use_dex_cache = GetCompilerOptions().GetCompilePic(); // Off by default
const bool compiling_boot = heap->IsCompilingBoot();
// TODO This is somewhat hacky. We should refactor all of this invoke codepath.
const bool force_relocations = (compiling_boot ||
GetCompilerOptions().GetIncludePatchInformation());
if (sharp_type != kStatic && sharp_type != kDirect) {
return;
}
// TODO: support patching on all architectures.
use_dex_cache = use_dex_cache || (force_relocations && !support_boot_image_fixup_);
mirror::Class* declaring_class = method->GetDeclaringClass();
bool method_code_in_boot = declaring_class->GetClassLoader() == nullptr;
if (!use_dex_cache) {
if (!method_code_in_boot) {
use_dex_cache = true;
} else {
bool has_clinit_trampoline =
method->IsStatic() && !declaring_class->IsInitialized();
if (has_clinit_trampoline && declaring_class != referrer_class) {
// Ensure we run the clinit trampoline unless we are invoking a static method in the same
// class.
use_dex_cache = true;
}
}
}
if (runtime->UseJitCompilation()) {
// If we are the JIT, then don't allow a direct call to the interpreter bridge since this will
// never be updated even after we compile the method.
if (cl->IsQuickToInterpreterBridge(
reinterpret_cast<const void*>(compiler_->GetEntryPointOf(method)))) {
use_dex_cache = true;
}
}
if (method_code_in_boot) {
*stats_flags |= kFlagDirectCallToBoot | kFlagDirectMethodToBoot;
}
if (!use_dex_cache && force_relocations) {
bool is_in_image;
if (IsBootImage()) {
is_in_image = IsImageClass(method->GetDeclaringClassDescriptor());
} else {
is_in_image = instruction_set_ != kX86 && instruction_set_ != kX86_64 &&
heap->FindSpaceFromObject(method->GetDeclaringClass(), false)->IsImageSpace() &&
!cl->IsQuickToInterpreterBridge(
reinterpret_cast<const void*>(compiler_->GetEntryPointOf(method)));
}
if (!is_in_image) {
// We can only branch directly to Methods that are resolved in the DexCache.
// Otherwise we won't invoke the resolution trampoline.
use_dex_cache = true;
}
}
// The method is defined not within this dex file. We need a dex cache slot within the current
// dex file or direct pointers.
bool must_use_direct_pointers = false;
mirror::DexCache* dex_cache = declaring_class->GetDexCache();
if (target_method->dex_file == dex_cache->GetDexFile() &&
!(runtime->UseJitCompilation() && dex_cache->GetResolvedMethod(
method->GetDexMethodIndex(), pointer_size) == nullptr)) {
target_method->dex_method_index = method->GetDexMethodIndex();
} else {
if (no_guarantee_of_dex_cache_entry) {
// See if the method is also declared in this dex cache.
uint32_t dex_method_idx = method->FindDexMethodIndexInOtherDexFile(
*target_method->dex_file, target_method->dex_method_index);
if (dex_method_idx != DexFile::kDexNoIndex) {
target_method->dex_method_index = dex_method_idx;
} else {
if (force_relocations && !use_dex_cache) {
target_method->dex_method_index = method->GetDexMethodIndex();
target_method->dex_file = dex_cache->GetDexFile();
}
must_use_direct_pointers = true;
}
}
}
if (use_dex_cache) {
if (must_use_direct_pointers) {
// Fail. Test above showed the only safe dispatch was via the dex cache, however, the direct
// pointers are required as the dex cache lacks an appropriate entry.
VLOG(compiler) << "Dex cache devirtualization failed for: " << PrettyMethod(method);
} else {
*type = sharp_type;
}
} else {
bool method_in_image = false;
const std::vector<gc::space::ImageSpace*> image_spaces = heap->GetBootImageSpaces();
for (gc::space::ImageSpace* image_space : image_spaces) {
const auto& method_section = image_space->GetImageHeader().GetMethodsSection();
if (method_section.Contains(reinterpret_cast<uint8_t*>(method) - image_space->Begin())) {
method_in_image = true;
break;
}
}
if (method_in_image || compiling_boot || runtime->UseJitCompilation()) {
// We know we must be able to get to the method in the image, so use that pointer.
// In the case where we are the JIT, we can always use direct pointers since we know where
// the method and its code are / will be. We don't sharpen to interpreter bridge since we
// check IsQuickToInterpreterBridge above.
CHECK(!method->IsAbstract());
*type = sharp_type;
*direct_method = force_relocations ? -1 : reinterpret_cast<uintptr_t>(method);
*direct_code = force_relocations ? -1 : compiler_->GetEntryPointOf(method);
target_method->dex_file = method->GetDeclaringClass()->GetDexCache()->GetDexFile();
target_method->dex_method_index = method->GetDexMethodIndex();
} else if (!must_use_direct_pointers) {
// Set the code and rely on the dex cache for the method.
*type = sharp_type;
if (force_relocations) {
*direct_code = -1;
target_method->dex_file = method->GetDeclaringClass()->GetDexCache()->GetDexFile();
target_method->dex_method_index = method->GetDexMethodIndex();
} else {
*direct_code = compiler_->GetEntryPointOf(method);
}
} else {
// Direct pointers were required but none were available.
VLOG(compiler) << "Dex cache devirtualization failed for: " << PrettyMethod(method);
}
}
}
bool CompilerDriver::ComputeInvokeInfo(const DexCompilationUnit* mUnit, const uint32_t dex_pc,
bool update_stats, bool enable_devirtualization,
InvokeType* invoke_type, MethodReference* target_method,
int* vtable_idx, uintptr_t* direct_code,
uintptr_t* direct_method) {
InvokeType orig_invoke_type = *invoke_type;
int stats_flags = 0;
ScopedObjectAccess soa(Thread::Current());
// Try to resolve the method and compiling method's class.
StackHandleScope<2> hs(soa.Self());
Handle<mirror::DexCache> dex_cache(mUnit->GetDexCache());
Handle<mirror::ClassLoader> class_loader(hs.NewHandle(
soa.Decode<mirror::ClassLoader*>(mUnit->GetClassLoader())));
uint32_t method_idx = target_method->dex_method_index;
ArtMethod* resolved_method = ResolveMethod(
soa, dex_cache, class_loader, mUnit, method_idx, orig_invoke_type);
auto h_referrer_class = hs.NewHandle(resolved_method != nullptr ?
ResolveCompilingMethodsClass(soa, dex_cache, class_loader, mUnit) : nullptr);
bool result = false;
if (resolved_method != nullptr) {
*vtable_idx = GetResolvedMethodVTableIndex(resolved_method, orig_invoke_type);
if (enable_devirtualization && mUnit->GetVerifiedMethod() != nullptr) {
const MethodReference* devirt_target = mUnit->GetVerifiedMethod()->GetDevirtTarget(dex_pc);
stats_flags = IsFastInvoke(
soa, dex_cache, class_loader, mUnit, h_referrer_class.Get(), resolved_method,
invoke_type, target_method, devirt_target, direct_code, direct_method);
result = stats_flags != 0;
} else {
// Devirtualization not enabled. Inline IsFastInvoke(), dropping the devirtualization parts.
if (UNLIKELY(h_referrer_class.Get() == nullptr) ||
UNLIKELY(!h_referrer_class->CanAccessResolvedMethod(resolved_method->GetDeclaringClass(),
resolved_method, dex_cache.Get(),
target_method->dex_method_index)) ||
*invoke_type == kSuper) {
// Slow path. (Without devirtualization, all super calls go slow path as well.)
} else {
// Sharpening failed so generate a regular resolved method dispatch.
stats_flags = kFlagMethodResolved;
GetCodeAndMethodForDirectCall(
invoke_type, *invoke_type, false, h_referrer_class.Get(), resolved_method, &stats_flags,
target_method, direct_code, direct_method);
result = true;
}
}
}
if (!result) {
// Conservative defaults.
*vtable_idx = -1;
*direct_code = 0u;
*direct_method = 0u;
}
if (update_stats) {
ProcessedInvoke(orig_invoke_type, stats_flags);
}
return result;
}
const VerifiedMethod* CompilerDriver::GetVerifiedMethod(const DexFile* dex_file,
uint32_t method_idx) const {
MethodReference ref(dex_file, method_idx);
return verification_results_->GetVerifiedMethod(ref);
}
bool CompilerDriver::IsSafeCast(const DexCompilationUnit* mUnit, uint32_t dex_pc) {
if (!compiler_options_->IsVerificationEnabled()) {
// If we didn't verify, every cast has to be treated as non-safe.
return false;
}
DCHECK(mUnit->GetVerifiedMethod() != nullptr);
bool result = mUnit->GetVerifiedMethod()->IsSafeCast(dex_pc);
if (result) {
stats_->SafeCast();
} else {
stats_->NotASafeCast();
}
return result;
}
class CompilationVisitor {
public:
virtual ~CompilationVisitor() {}
virtual void Visit(size_t index) = 0;
};
class ParallelCompilationManager {
public:
ParallelCompilationManager(ClassLinker* class_linker,
jobject class_loader,
CompilerDriver* compiler,
const DexFile* dex_file,
const std::vector<const DexFile*>& dex_files,
ThreadPool* thread_pool)
: index_(0),
class_linker_(class_linker),
class_loader_(class_loader),
compiler_(compiler),
dex_file_(dex_file),
dex_files_(dex_files),
thread_pool_(thread_pool) {}
ClassLinker* GetClassLinker() const {
CHECK(class_linker_ != nullptr);
return class_linker_;
}
jobject GetClassLoader() const {
return class_loader_;
}
CompilerDriver* GetCompiler() const {
CHECK(compiler_ != nullptr);
return compiler_;
}
const DexFile* GetDexFile() const {
CHECK(dex_file_ != nullptr);
return dex_file_;
}
const std::vector<const DexFile*>& GetDexFiles() const {
return dex_files_;
}
void ForAll(size_t begin, size_t end, CompilationVisitor* visitor, size_t work_units)
REQUIRES(!*Locks::mutator_lock_) {
Thread* self = Thread::Current();
self->AssertNoPendingException();
CHECK_GT(work_units, 0U);
index_.StoreRelaxed(begin);
for (size_t i = 0; i < work_units; ++i) {
thread_pool_->AddTask(self, new ForAllClosure(this, end, visitor));
}
thread_pool_->StartWorkers(self);
// Ensure we're suspended while we're blocked waiting for the other threads to finish (worker
// thread destructor's called below perform join).
CHECK_NE(self->GetState(), kRunnable);
// Wait for all the worker threads to finish.
thread_pool_->Wait(self, true, false);
// And stop the workers accepting jobs.
thread_pool_->StopWorkers(self);
}
size_t NextIndex() {
return index_.FetchAndAddSequentiallyConsistent(1);
}
private:
class ForAllClosure : public Task {
public:
ForAllClosure(ParallelCompilationManager* manager, size_t end, CompilationVisitor* visitor)
: manager_(manager),
end_(end),
visitor_(visitor) {}
virtual void Run(Thread* self) {
while (true) {
const size_t index = manager_->NextIndex();
if (UNLIKELY(index >= end_)) {
break;
}
visitor_->Visit(index);
self->AssertNoPendingException();
}
}
virtual void Finalize() {
delete this;
}
private:
ParallelCompilationManager* const manager_;
const size_t end_;
CompilationVisitor* const visitor_;
};
AtomicInteger index_;
ClassLinker* const class_linker_;
const jobject class_loader_;
CompilerDriver* const compiler_;
const DexFile* const dex_file_;
const std::vector<const DexFile*>& dex_files_;
ThreadPool* const thread_pool_;
DISALLOW_COPY_AND_ASSIGN(ParallelCompilationManager);
};
// A fast version of SkipClass above if the class pointer is available
// that avoids the expensive FindInClassPath search.
static bool SkipClass(jobject class_loader, const DexFile& dex_file, mirror::Class* klass)
SHARED_REQUIRES(Locks::mutator_lock_) {
DCHECK(klass != nullptr);
const DexFile& original_dex_file = *klass->GetDexCache()->GetDexFile();
if (&dex_file != &original_dex_file) {
if (class_loader == nullptr) {
LOG(WARNING) << "Skipping class " << PrettyDescriptor(klass) << " from "
<< dex_file.GetLocation() << " previously found in "
<< original_dex_file.GetLocation();
}
return true;
}
return false;
}
static void CheckAndClearResolveException(Thread* self)
SHARED_REQUIRES(Locks::mutator_lock_) {
CHECK(self->IsExceptionPending());
mirror::Throwable* exception = self->GetException();
std::string temp;
const char* descriptor = exception->GetClass()->GetDescriptor(&temp);
const char* expected_exceptions[] = {
"Ljava/lang/IllegalAccessError;",
"Ljava/lang/IncompatibleClassChangeError;",
"Ljava/lang/InstantiationError;",
"Ljava/lang/LinkageError;",
"Ljava/lang/NoClassDefFoundError;",
"Ljava/lang/NoSuchFieldError;",
"Ljava/lang/NoSuchMethodError;"
};
bool found = false;
for (size_t i = 0; (found == false) && (i < arraysize(expected_exceptions)); ++i) {
if (strcmp(descriptor, expected_exceptions[i]) == 0) {
found = true;
}
}
if (!found) {
LOG(FATAL) << "Unexpected exception " << exception->Dump();
}
self->ClearException();
}
bool CompilerDriver::RequiresConstructorBarrier(const DexFile& dex_file,
uint16_t class_def_idx) const {
const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_idx);
const uint8_t* class_data = dex_file.GetClassData(class_def);
if (class_data == nullptr) {
// Empty class such as a marker interface.
return false;
}
ClassDataItemIterator it(dex_file, class_data);
while (it.HasNextStaticField()) {
it.Next();
}
// We require a constructor barrier if there are final instance fields.
while (it.HasNextInstanceField()) {
if (it.MemberIsFinal()) {
return true;
}
it.Next();
}
return false;
}
class ResolveClassFieldsAndMethodsVisitor : public CompilationVisitor {
public:
explicit ResolveClassFieldsAndMethodsVisitor(const ParallelCompilationManager* manager)
: manager_(manager) {}
void Visit(size_t class_def_index) OVERRIDE REQUIRES(!Locks::mutator_lock_) {
ATRACE_CALL();
Thread* const self = Thread::Current();
jobject jclass_loader = manager_->GetClassLoader();
const DexFile& dex_file = *manager_->GetDexFile();
ClassLinker* class_linker = manager_->GetClassLinker();
// If an instance field is final then we need to have a barrier on the return, static final
// fields are assigned within the lock held for class initialization. Conservatively assume
// constructor barriers are always required.
bool requires_constructor_barrier = true;
// Method and Field are the worst. We can't resolve without either
// context from the code use (to disambiguate virtual vs direct
// method and instance vs static field) or from class
// definitions. While the compiler will resolve what it can as it
// needs it, here we try to resolve fields and methods used in class
// definitions, since many of them many never be referenced by
// generated code.
const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);
ScopedObjectAccess soa(self);
StackHandleScope<2> hs(soa.Self());
Handle<mirror::ClassLoader> class_loader(
hs.NewHandle(soa.Decode<mirror::ClassLoader*>(jclass_loader)));
Handle<mirror::DexCache> dex_cache(hs.NewHandle(class_linker->FindDexCache(
soa.Self(), dex_file, false)));
// Resolve the class.
mirror::Class* klass = class_linker->ResolveType(dex_file, class_def.class_idx_, dex_cache,
class_loader);
bool resolve_fields_and_methods;
if (klass == nullptr) {
// Class couldn't be resolved, for example, super-class is in a different dex file. Don't
// attempt to resolve methods and fields when there is no declaring class.
CheckAndClearResolveException(soa.Self());
resolve_fields_and_methods = false;
} else {
// We successfully resolved a class, should we skip it?
if (SkipClass(jclass_loader, dex_file, klass)) {
return;
}
// We want to resolve the methods and fields eagerly.
resolve_fields_and_methods = true;
}
// Note the class_data pointer advances through the headers,
// static fields, instance fields, direct methods, and virtual
// methods.
const uint8_t* class_data = dex_file.GetClassData(class_def);
if (class_data == nullptr) {
// Empty class such as a marker interface.
requires_constructor_barrier = false;
} else {
ClassDataItemIterator it(dex_file, class_data);
while (it.HasNextStaticField()) {
if (resolve_fields_and_methods) {
ArtField* field = class_linker->ResolveField(dex_file, it.GetMemberIndex(),
dex_cache, class_loader, true);
if (field == nullptr) {
CheckAndClearResolveException(soa.Self());
}
}
it.Next();
}
// We require a constructor barrier if there are final instance fields.
requires_constructor_barrier = false;
while (it.HasNextInstanceField()) {
if (it.MemberIsFinal()) {
requires_constructor_barrier = true;
}
if (resolve_fields_and_methods) {
ArtField* field = class_linker->ResolveField(dex_file, it.GetMemberIndex(),
dex_cache, class_loader, false);
if (field == nullptr) {
CheckAndClearResolveException(soa.Self());
}
}
it.Next();
}
if (resolve_fields_and_methods) {
while (it.HasNextDirectMethod()) {
ArtMethod* method = class_linker->ResolveMethod<ClassLinker::kNoICCECheckForCache>(
dex_file, it.GetMemberIndex(), dex_cache, class_loader, nullptr,
it.GetMethodInvokeType(class_def));
if (method == nullptr) {
CheckAndClearResolveException(soa.Self());
}
it.Next();
}
while (it.HasNextVirtualMethod()) {
ArtMethod* method = class_linker->ResolveMethod<ClassLinker::kNoICCECheckForCache>(
dex_file, it.GetMemberIndex(), dex_cache, class_loader, nullptr,
it.GetMethodInvokeType(class_def));
if (method == nullptr) {
CheckAndClearResolveException(soa.Self());
}
it.Next();
}
DCHECK(!it.HasNext());
}
}
manager_->GetCompiler()->SetRequiresConstructorBarrier(self,
&dex_file,
class_def_index,
requires_constructor_barrier);
}
private:
const ParallelCompilationManager* const manager_;
};
class ResolveTypeVisitor : public CompilationVisitor {
public:
explicit ResolveTypeVisitor(const ParallelCompilationManager* manager) : manager_(manager) {
}
virtual void Visit(size_t type_idx) OVERRIDE REQUIRES(!Locks::mutator_lock_) {
// Class derived values are more complicated, they require the linker and loader.
ScopedObjectAccess soa(Thread::Current());
ClassLinker* class_linker = manager_->GetClassLinker();
const DexFile& dex_file = *manager_->GetDexFile();
StackHandleScope<2> hs(soa.Self());
Handle<mirror::ClassLoader> class_loader(
hs.NewHandle(soa.Decode<mirror::ClassLoader*>(manager_->GetClassLoader())));
Handle<mirror::DexCache> dex_cache(hs.NewHandle(class_linker->RegisterDexFile(
dex_file,
class_linker->GetOrCreateAllocatorForClassLoader(class_loader.Get()))));
mirror::Class* klass = class_linker->ResolveType(dex_file, type_idx, dex_cache, class_loader);
if (klass == nullptr) {
soa.Self()->AssertPendingException();
mirror::Throwable* exception = soa.Self()->GetException();
VLOG(compiler) << "Exception during type resolution: " << exception->Dump();
if (exception->GetClass()->DescriptorEquals("Ljava/lang/OutOfMemoryError;")) {
// There's little point continuing compilation if the heap is exhausted.
LOG(FATAL) << "Out of memory during type resolution for compilation";
}
soa.Self()->ClearException();
}
}
private:
const ParallelCompilationManager* const manager_;
};
void CompilerDriver::ResolveDexFile(jobject class_loader,
const DexFile& dex_file,
const std::vector<const DexFile*>& dex_files,
ThreadPool* thread_pool,
size_t thread_count,
TimingLogger* timings) {
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
// TODO: we could resolve strings here, although the string table is largely filled with class
// and method names.
ParallelCompilationManager context(class_linker, class_loader, this, &dex_file, dex_files,
thread_pool);
if (IsBootImage()) {
// For images we resolve all types, such as array, whereas for applications just those with
// classdefs are resolved by ResolveClassFieldsAndMethods.
TimingLogger::ScopedTiming t("Resolve Types", timings);
ResolveTypeVisitor visitor(&context);
context.ForAll(0, dex_file.NumTypeIds(), &visitor, thread_count);
}
TimingLogger::ScopedTiming t("Resolve MethodsAndFields", timings);
ResolveClassFieldsAndMethodsVisitor visitor(&context);
context.ForAll(0, dex_file.NumClassDefs(), &visitor, thread_count);
}
void CompilerDriver::SetVerified(jobject class_loader,
const std::vector<const DexFile*>& dex_files,
TimingLogger* timings) {
// This can be run in parallel.
for (const DexFile* dex_file : dex_files) {
CHECK(dex_file != nullptr);
SetVerifiedDexFile(class_loader,
*dex_file,
dex_files,
parallel_thread_pool_.get(),
parallel_thread_count_,
timings);
}
}
void CompilerDriver::Verify(jobject class_loader,
const std::vector<const DexFile*>& dex_files,
TimingLogger* timings) {
// Note: verification should not be pulling in classes anymore when compiling the boot image,
// as all should have been resolved before. As such, doing this in parallel should still
// be deterministic.
for (const DexFile* dex_file : dex_files) {
CHECK(dex_file != nullptr);
VerifyDexFile(class_loader,
*dex_file,
dex_files,
parallel_thread_pool_.get(),
parallel_thread_count_,
timings);
}
}
class VerifyClassVisitor : public CompilationVisitor {
public:
VerifyClassVisitor(const ParallelCompilationManager* manager, LogSeverity log_level)
: manager_(manager), log_level_(log_level) {}
virtual void Visit(size_t class_def_index) REQUIRES(!Locks::mutator_lock_) OVERRIDE {
ATRACE_CALL();
ScopedObjectAccess soa(Thread::Current());
const DexFile& dex_file = *manager_->GetDexFile();
if (!manager_->GetCompiler()->ShouldVerifyClassBasedOnProfile(dex_file, class_def_index)) {
// Skip verification since the class is not in the profile.
return;
}
const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);
const char* descriptor = dex_file.GetClassDescriptor(class_def);
ClassLinker* class_linker = manager_->GetClassLinker();
jobject jclass_loader = manager_->GetClassLoader();
StackHandleScope<3> hs(soa.Self());
Handle<mirror::ClassLoader> class_loader(
hs.NewHandle(soa.Decode<mirror::ClassLoader*>(jclass_loader)));
Handle<mirror::Class> klass(
hs.NewHandle(class_linker->FindClass(soa.Self(), descriptor, class_loader)));
if (klass.Get() == nullptr) {
CHECK(soa.Self()->IsExceptionPending());
soa.Self()->ClearException();
/*
* At compile time, we can still structurally verify the class even if FindClass fails.
* This is to ensure the class is structurally sound for compilation. An unsound class
* will be rejected by the verifier and later skipped during compilation in the compiler.
*/
Handle<mirror::DexCache> dex_cache(hs.NewHandle(class_linker->FindDexCache(
soa.Self(), dex_file, false)));
std::string error_msg;
if (verifier::MethodVerifier::VerifyClass(soa.Self(),
&dex_file,
dex_cache,
class_loader,
&class_def,
Runtime::Current()->GetCompilerCallbacks(),
true /* allow soft failures */,
log_level_,
&error_msg) ==
verifier::MethodVerifier::kHardFailure) {
LOG(ERROR) << "Verification failed on class " << PrettyDescriptor(descriptor)
<< " because: " << error_msg;
manager_->GetCompiler()->SetHadHardVerifierFailure();
}
} else if (!SkipClass(jclass_loader, dex_file, klass.Get())) {
CHECK(klass->IsResolved()) << PrettyClass(klass.Get());
class_linker->VerifyClass(soa.Self(), klass, log_level_);
if (klass->IsErroneous()) {
// ClassLinker::VerifyClass throws, which isn't useful in the compiler.
CHECK(soa.Self()->IsExceptionPending());
soa.Self()->ClearException();
manager_->GetCompiler()->SetHadHardVerifierFailure();
}
CHECK(klass->IsCompileTimeVerified() || klass->IsErroneous())
<< PrettyDescriptor(klass.Get()) << ": state=" << klass->GetStatus();
// It is *very* problematic if there are verification errors in the boot classpath. For example,
// we rely on things working OK without verification when the decryption dialog is brought up.
// So abort in a debug build if we find this violated.
DCHECK(!manager_->GetCompiler()->IsBootImage() || klass->IsVerified())
<< "Boot classpath class " << PrettyClass(klass.Get()) << " failed to fully verify.";
}
soa.Self()->AssertNoPendingException();
}
private:
const ParallelCompilationManager* const manager_;
const LogSeverity log_level_;
};
void CompilerDriver::VerifyDexFile(jobject class_loader,
const DexFile& dex_file,
const std::vector<const DexFile*>& dex_files,
ThreadPool* thread_pool,
size_t thread_count,
TimingLogger* timings) {
TimingLogger::ScopedTiming t("Verify Dex File", timings);
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
ParallelCompilationManager context(class_linker, class_loader, this, &dex_file, dex_files,
thread_pool);
LogSeverity log_level = GetCompilerOptions().AbortOnHardVerifierFailure()
? LogSeverity::INTERNAL_FATAL
: LogSeverity::WARNING;
VerifyClassVisitor visitor(&context, log_level);
context.ForAll(0, dex_file.NumClassDefs(), &visitor, thread_count);
}
class SetVerifiedClassVisitor : public CompilationVisitor {
public:
explicit SetVerifiedClassVisitor(const ParallelCompilationManager* manager) : manager_(manager) {}
virtual void Visit(size_t class_def_index) REQUIRES(!Locks::mutator_lock_) OVERRIDE {
ATRACE_CALL();
ScopedObjectAccess soa(Thread::Current());
const DexFile& dex_file = *manager_->GetDexFile();
const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);
const char* descriptor = dex_file.GetClassDescriptor(class_def);
ClassLinker* class_linker = manager_->GetClassLinker();
jobject jclass_loader = manager_->GetClassLoader();
StackHandleScope<3> hs(soa.Self());
Handle<mirror::ClassLoader> class_loader(
hs.NewHandle(soa.Decode<mirror::ClassLoader*>(jclass_loader)));
Handle<mirror::Class> klass(
hs.NewHandle(class_linker->FindClass(soa.Self(), descriptor, class_loader)));
// Class might have failed resolution. Then don't set it to verified.
if (klass.Get() != nullptr) {
// Only do this if the class is resolved. If even resolution fails, quickening will go very,
// very wrong.
if (klass->IsResolved()) {
if (klass->GetStatus() < mirror::Class::kStatusVerified) {
ObjectLock<mirror::Class> lock(soa.Self(), klass);
// Set class status to verified.
mirror::Class::SetStatus(klass, mirror::Class::kStatusVerified, soa.Self());
// Mark methods as pre-verified. If we don't do this, the interpreter will run with
// access checks.
klass->SetSkipAccessChecksFlagOnAllMethods(
GetInstructionSetPointerSize(manager_->GetCompiler()->GetInstructionSet()));
klass->SetVerificationAttempted();
}
// Record the final class status if necessary.
ClassReference ref(manager_->GetDexFile(), class_def_index);
manager_->GetCompiler()->RecordClassStatus(ref, klass->GetStatus());
}
} else {
Thread* self = soa.Self();
DCHECK(self->IsExceptionPending());
self->ClearException();
}
}
private:
const ParallelCompilationManager* const manager_;
};
void CompilerDriver::SetVerifiedDexFile(jobject class_loader,
const DexFile& dex_file,
const std::vector<const DexFile*>& dex_files,
ThreadPool* thread_pool,
size_t thread_count,
TimingLogger* timings) {
TimingLogger::ScopedTiming t("Verify Dex File", timings);
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
ParallelCompilationManager context(class_linker, class_loader, this, &dex_file, dex_files,
thread_pool);
SetVerifiedClassVisitor visitor(&context);
context.ForAll(0, dex_file.NumClassDefs(), &visitor, thread_count);
}
class InitializeClassVisitor : public CompilationVisitor {
public:
explicit InitializeClassVisitor(const ParallelCompilationManager* manager) : manager_(manager) {}
virtual void Visit(size_t class_def_index) REQUIRES(!Locks::mutator_lock_) OVERRIDE {
ATRACE_CALL();
jobject jclass_loader = manager_->GetClassLoader();
const DexFile& dex_file = *manager_->GetDexFile();
const DexFile::ClassDef& class_def = dex_file.GetClassDef(class_def_index);
const DexFile::TypeId& class_type_id = dex_file.GetTypeId(class_def.class_idx_);
const char* descriptor = dex_file.StringDataByIdx(class_type_id.descriptor_idx_);
ScopedObjectAccess soa(Thread::Current());
StackHandleScope<3> hs(soa.Self());
Handle<mirror::ClassLoader> class_loader(
hs.NewHandle(soa.Decode<mirror::ClassLoader*>(jclass_loader)));
Handle<mirror::Class> klass(
hs.NewHandle(manager_->GetClassLinker()->FindClass(soa.Self(), descriptor, class_loader)));
if (klass.Get() != nullptr && !SkipClass(jclass_loader, dex_file, klass.Get())) {
// Only try to initialize classes that were successfully verified.
if (klass->IsVerified()) {
// Attempt to initialize the class but bail if we either need to initialize the super-class
// or static fields.
manager_->GetClassLinker()->EnsureInitialized(soa.Self(), klass, false, false);
if (!klass->IsInitialized()) {
// We don't want non-trivial class initialization occurring on multiple threads due to
// deadlock problems. For example, a parent class is initialized (holding its lock) that
// refers to a sub-class in its static/class initializer causing it to try to acquire the
// sub-class' lock. While on a second thread the sub-class is initialized (holding its lock)
// after first initializing its parents, whose locks are acquired. This leads to a
// parent-to-child and a child-to-parent lock ordering and consequent potential deadlock.
// We need to use an ObjectLock due to potential suspension in the interpreting code. Rather
// than use a special Object for the purpose we use the Class of java.lang.Class.
Handle<mirror::Class> h_klass(hs.NewHandle(klass->GetClass()));
ObjectLock<mirror::Class> lock(soa.Self(), h_klass);
// Attempt to initialize allowing initialization of parent classes but still not static
// fields.
manager_->GetClassLinker()->EnsureInitialized(soa.Self(), klass, false, true);
if (!klass->IsInitialized()) {
// We need to initialize static fields, we only do this for image classes that aren't
// marked with the $NoPreloadHolder (which implies this should not be initialized early).
bool can_init_static_fields = manager_->GetCompiler()->IsBootImage() &&
manager_->GetCompiler()->IsImageClass(descriptor) &&
!StringPiece(descriptor).ends_with("$NoPreloadHolder;");
if (can_init_static_fields) {
VLOG(compiler) << "Initializing: " << descriptor;
// TODO multithreading support. We should ensure the current compilation thread has
// exclusive access to the runtime and the transaction. To achieve this, we could use
// a ReaderWriterMutex but we're holding the mutator lock so we fail mutex sanity
// checks in Thread::AssertThreadSuspensionIsAllowable.
Runtime* const runtime = Runtime::Current();
Transaction transaction;
// Run the class initializer in transaction mode.
runtime->EnterTransactionMode(&transaction);
const mirror::Class::Status old_status = klass->GetStatus();
bool success = manager_->GetClassLinker()->EnsureInitialized(soa.Self(), klass, true,
true);
// TODO we detach transaction from runtime to indicate we quit the transactional
// mode which prevents the GC from visiting objects modified during the transaction.
// Ensure GC is not run so don't access freed objects when aborting transaction.
ScopedAssertNoThreadSuspension ants(soa.Self(), "Transaction end");
runtime->ExitTransactionMode();
if (!success) {
CHECK(soa.Self()->IsExceptionPending());
mirror::Throwable* exception = soa.Self()->GetException();
VLOG(compiler) << "Initialization of " << descriptor << " aborted because of "
<< exception->Dump();
std::ostream* file_log = manager_->GetCompiler()->
GetCompilerOptions().GetInitFailureOutput();
if (file_log != nullptr) {
*file_log << descriptor << "\n";
*file_log << exception->Dump() << "\n";
}
soa.Self()->ClearException();
transaction.Rollback();
CHECK_EQ(old_status, klass->GetStatus()) << "Previous class status not restored";
}
}
}
soa.Self()->AssertNoPendingException();
}
}
// Record the final class status if necessary.
ClassReference ref(manager_->GetDexFile(), class_def_index);
manager_->GetCompiler()->RecordClassStatus(ref, klass->GetStatus());
}
// Clear any class not found or verification exceptions.
soa.Self()->ClearException();
}
private:
const ParallelCompilationManager* const manager_;
};
void CompilerDriver::InitializeClasses(jobject jni_class_loader,
const DexFile& dex_file,
const std::vector<const DexFile*>& dex_files,
TimingLogger* timings) {
TimingLogger::ScopedTiming t("InitializeNoClinit", timings);
// Initialization allocates objects and needs to run single-threaded to be deterministic.
bool force_determinism = GetCompilerOptions().IsForceDeterminism();
ThreadPool* init_thread_pool = force_determinism
? single_thread_pool_.get()
: parallel_thread_pool_.get();
size_t init_thread_count = force_determinism ? 1U : parallel_thread_count_;
ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
ParallelCompilationManager context(class_linker, jni_class_loader, this, &dex_file, dex_files,
init_thread_pool);
if (IsBootImage()) {
// TODO: remove this when transactional mode supports multithreading.
init_thread_count = 1U;
}
InitializeClassVisitor visitor(&context);
context.ForAll(0, dex_file.NumClassDefs(), &visitor, init_thread_count);
}
class InitializeArrayClassesAndCreateConflictTablesVisitor : public ClassVisitor {
public:
virtual bool operator()(mirror::Class* klass) OVERRIDE SHARED_REQUIRES(Locks::mutator_lock_) {
if (Runtime::Current()->GetHeap()->ObjectIsInBootImageSpace(klass)) {
return true;
}
if (klass->IsArrayClass()) {
StackHandleScope<1> hs(Thread::Current());
Runtime::Current()->GetClassLinker()->EnsureInitialized(hs.Self(),
hs.NewHandle(klass),
true,
true);
}
// Create the conflict tables.
if (!klass->IsTemp() && klass->ShouldHaveEmbeddedImtAndVTable()) {
Runtime::Current()->GetClassLinker()->FillIMTAndConflictTables(klass);
}
return true;
}
};
void CompilerDriver::InitializeClasses(jobject class_loader,
const std::vector<const DexFile*>& dex_files,
TimingLogger* timings) {
for (size_t i = 0; i != dex_files.size(); ++i) {
const DexFile* dex_file = dex_files[i];
CHECK(dex_file != nullptr);
InitializeClasses(class_loader, *dex_file, dex_files, timings);
}
if (boot_image_ || app_image_) {
// Make sure that we call EnsureIntiailized on all the array classes to call
// SetVerificationAttempted so that the access flags are set. If we do not do this they get
// changed at runtime resulting in more dirty image pages.
// Also create conflict tables.
// Only useful if we are compiling an image (image_classes_ is not null).
ScopedObjectAccess soa(Thread::Current());
InitializeArrayClassesAndCreateConflictTablesVisitor visitor;
Runtime::Current()->GetClassLinker()->VisitClassesWithoutClassesLock(&visitor);
}
if (IsBootImage()) {
// Prune garbage objects created during aborted transactions.
Runtime::Current()->GetHeap()->CollectGarbage(true);
}
}