runtime/jit/jit_code_cache.h - SHIFTPHONES/android_art - Gitiles

 /*
  * Copyright 2014 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.
  */

 #ifndef ART_RUNTIME_JIT_JIT_CODE_CACHE_H_
 #define ART_RUNTIME_JIT_JIT_CODE_CACHE_H_

 #include <iosfwd>
 #include <memory>
 #include <set>
 #include <string>
 #include <unordered_set>
 #include <vector>

 #include "base/arena_containers.h"
 #include "base/atomic.h"
 #include "base/histogram.h"
 #include "base/macros.h"
 #include "base/mutex.h"
 #include "base/safe_map.h"

 namespace art {

 class ArtMethod;
 template<class T> class Handle;
 class LinearAlloc;
 class InlineCache;
 class IsMarkedVisitor;
 class JitJniStubTestHelper;
 class MemMap;
 class OatQuickMethodHeader;
 struct ProfileMethodInfo;
 class ProfilingInfo;
 class Thread;

 namespace gc {
 namespace accounting {
 template<size_t kAlignment> class MemoryRangeBitmap;
 }  // namespace accounting
 }  // namespace gc

 namespace mirror {
 class Class;
 class Object;
 template<class T> class ObjectArray;
 }  // namespace mirror

 namespace gc {
 namespace accounting {
 template<size_t kAlignment> class MemoryRangeBitmap;
 }  // namespace accounting
 }  // namespace gc

 namespace mirror {
 class Class;
 class Object;
 template<class T> class ObjectArray;
 }  // namespace mirror

 namespace jit {

 class JitInstrumentationCache;
 class ScopedCodeCacheWrite;

 // Alignment in bits that will suit all architectures.
 static constexpr int kJitCodeAlignment = 16;
 using CodeCacheBitmap = gc::accounting::MemoryRangeBitmap<kJitCodeAlignment>;

 class JitCodeCache {
  public:
   static constexpr size_t kMaxCapacity = 64 * MB;
   // Put the default to a very low amount for debug builds to stress the code cache
   // collection.
   static constexpr size_t kInitialCapacity = kIsDebugBuild ? 8 * KB : 64 * KB;

   // By default, do not GC until reaching 256KB.
   static constexpr size_t kReservedCapacity = kInitialCapacity * 4;

   // Create the code cache with a code + data capacity equal to "capacity", error message is passed
   // in the out arg error_msg.
   static JitCodeCache* Create(size_t initial_capacity,
                               size_t max_capacity,
                               bool generate_debug_info,
                               bool used_only_for_profile_data,
                               std::string* error_msg);
   ~JitCodeCache();

   // Number of bytes allocated in the code cache.
   size_t CodeCacheSize() REQUIRES(!lock_);

   // Number of bytes allocated in the data cache.
   size_t DataCacheSize() REQUIRES(!lock_);

   bool NotifyCompilationOf(ArtMethod* method, Thread* self, bool osr)
       REQUIRES_SHARED(Locks::mutator_lock_)
       REQUIRES(!lock_);

   void NotifyMethodRedefined(ArtMethod* method)
       REQUIRES(Locks::mutator_lock_)
       REQUIRES(!lock_);

   // Notify to the code cache that the compiler wants to use the
   // profiling info of `method` to drive optimizations,
   // and therefore ensure the returned profiling info object is not
   // collected.
   ProfilingInfo* NotifyCompilerUse(ArtMethod* method, Thread* self)
       REQUIRES_SHARED(Locks::mutator_lock_)
       REQUIRES(!lock_);

   void DoneCompiling(ArtMethod* method, Thread* self, bool osr)
       REQUIRES_SHARED(Locks::mutator_lock_)
       REQUIRES(!lock_);

   void DoneCompilerUse(ArtMethod* method, Thread* self)
       REQUIRES_SHARED(Locks::mutator_lock_)
       REQUIRES(!lock_);

   // Allocate and write code and its metadata to the code cache.
   // `cha_single_implementation_list` needs to be registered via CHA (if it's
   // still valid), since the compiled code still needs to be invalidated if the
   // single-implementation assumptions are violated later. This needs to be done
   // even if `has_should_deoptimize_flag` is false, which can happen due to CHA
   // guard elimination.
   uint8_t* CommitCode(Thread* self,
                       ArtMethod* method,
                       uint8_t* stack_map,
                       uint8_t* roots_data,
                       const uint8_t* code,
                       size_t code_size,
                       size_t data_size,
                       bool osr,
                       Handle<mirror::ObjectArray<mirror::Object>> roots,
                       bool has_should_deoptimize_flag,
                       const ArenaSet<ArtMethod*>& cha_single_implementation_list)
       REQUIRES_SHARED(Locks::mutator_lock_)
       REQUIRES(!lock_);

   // Return true if the code cache contains this pc.
   bool ContainsPc(const void* pc) const;

   // Returns true if either the method's entrypoint is JIT compiled code or it is the
   // instrumentation entrypoint and we can jump to jit code for this method. For testing use only.
   bool WillExecuteJitCode(ArtMethod* method) REQUIRES(!lock_);

   // Return true if the code cache contains this method.
   bool ContainsMethod(ArtMethod* method) REQUIRES(!lock_);

   // Return the code pointer for a JNI-compiled stub if the method is in the cache, null otherwise.
   const void* GetJniStubCode(ArtMethod* method) REQUIRES(!lock_);

   // Allocate a region of data that contain `size` bytes, and potentially space
   // for storing `number_of_roots` roots. Returns null if there is no more room.
   // Return the number of bytes allocated.
   size_t ReserveData(Thread* self,
                      size_t stack_map_size,
                      size_t number_of_roots,
                      ArtMethod* method,
                      uint8_t** stack_map_data,
                      uint8_t** roots_data)
       REQUIRES_SHARED(Locks::mutator_lock_)
       REQUIRES(!lock_);

   // Clear data from the data portion of the code cache.
   void ClearData(Thread* self, uint8_t* stack_map_data, uint8_t* roots_data)
       REQUIRES_SHARED(Locks::mutator_lock_)
       REQUIRES(!lock_);

   CodeCacheBitmap* GetLiveBitmap() const {
     return live_bitmap_.get();
   }

   // Perform a collection on the code cache.
   void GarbageCollectCache(Thread* self)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   // Given the 'pc', try to find the JIT compiled code associated with it.
   // Return null if 'pc' is not in the code cache. 'method' is passed for
   // sanity check.
   OatQuickMethodHeader* LookupMethodHeader(uintptr_t pc, ArtMethod* method)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   OatQuickMethodHeader* LookupOsrMethodHeader(ArtMethod* method)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   // Removes method from the cache for testing purposes. The caller
   // must ensure that all threads are suspended and the method should
   // not be in any thread's stack.
   bool RemoveMethod(ArtMethod* method, bool release_memory)
       REQUIRES(!lock_)
       REQUIRES(Locks::mutator_lock_);

   // Remove all methods in our cache that were allocated by 'alloc'.
   void RemoveMethodsIn(Thread* self, const LinearAlloc& alloc)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   void CopyInlineCacheInto(const InlineCache& ic, Handle<mirror::ObjectArray<mirror::Class>> array)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   // Create a 'ProfileInfo' for 'method'. If 'retry_allocation' is true,
   // will collect and retry if the first allocation is unsuccessful.
   ProfilingInfo* AddProfilingInfo(Thread* self,
                                   ArtMethod* method,
                                   const std::vector<uint32_t>& entries,
                                   bool retry_allocation)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   bool OwnsSpace(const void* mspace) const NO_THREAD_SAFETY_ANALYSIS {
     return mspace == code_mspace_ || mspace == data_mspace_;
   }

   void* MoreCore(const void* mspace, intptr_t increment);

   // Adds to `methods` all profiled methods which are part of any of the given dex locations.
   void GetProfiledMethods(const std::set<std::string>& dex_base_locations,
                           std::vector<ProfileMethodInfo>& methods)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   uint64_t GetLastUpdateTimeNs() const;

   size_t GetMemorySizeOfCodePointer(const void* ptr) REQUIRES(!lock_);

   void InvalidateCompiledCodeFor(ArtMethod* method, const OatQuickMethodHeader* code)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   void Dump(std::ostream& os) REQUIRES(!lock_);

   bool IsOsrCompiled(ArtMethod* method) REQUIRES(!lock_);

   void SweepRootTables(IsMarkedVisitor* visitor)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   // The GC needs to disallow the reading of inline caches when it processes them,
   // to avoid having a class being used while it is being deleted.
   void AllowInlineCacheAccess() REQUIRES(!lock_);
   void DisallowInlineCacheAccess() REQUIRES(!lock_);
   void BroadcastForInlineCacheAccess() REQUIRES(!lock_);

   // Notify the code cache that the method at the pointer 'old_method' is being moved to the pointer
   // 'new_method' since it is being made obsolete.
   void MoveObsoleteMethod(ArtMethod* old_method, ArtMethod* new_method)
       REQUIRES(!lock_) REQUIRES(Locks::mutator_lock_);

   // Dynamically change whether we want to garbage collect code. Should only be used
   // by tests.
   void SetGarbageCollectCode(bool value) {
     garbage_collect_code_ = value;
   }

   bool GetGarbageCollectCode() const {
     return garbage_collect_code_;
   }

   // If Jit-gc has been disabled (and instrumentation has been enabled) this will return the
   // jit-compiled entrypoint for this method.  Otherwise it will return null.
   const void* FindCompiledCodeForInstrumentation(ArtMethod* method)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

  private:
   // Take ownership of maps.
   JitCodeCache(MemMap* code_map,
                MemMap* data_map,
                size_t initial_code_capacity,
                size_t initial_data_capacity,
                size_t max_capacity,
                bool garbage_collect_code,
                int memmap_flags_prot_code);

   // Internal version of 'CommitCode' that will not retry if the
   // allocation fails. Return null if the allocation fails.
   uint8_t* CommitCodeInternal(Thread* self,
                               ArtMethod* method,
                               uint8_t* stack_map,
                               uint8_t* roots_data,
                               const uint8_t* code,
                               size_t code_size,
                               size_t data_size,
                               bool osr,
                               Handle<mirror::ObjectArray<mirror::Object>> roots,
                               bool has_should_deoptimize_flag,
                               const ArenaSet<ArtMethod*>& cha_single_implementation_list)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   // Adds the given roots to the roots_data. Only a member for annotalysis.
   void FillRootTable(uint8_t* roots_data, Handle<mirror::ObjectArray<mirror::Object>> roots)
       REQUIRES(lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   ProfilingInfo* AddProfilingInfoInternal(Thread* self,
                                           ArtMethod* method,
                                           const std::vector<uint32_t>& entries)
       REQUIRES(lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   // If a collection is in progress, wait for it to finish. Return
   // whether the thread actually waited.
   bool WaitForPotentialCollectionToComplete(Thread* self)
       REQUIRES(lock_) REQUIRES(!Locks::mutator_lock_);

   // Remove CHA dependents and underlying allocations for entries in `method_headers`.
   void FreeAllMethodHeaders(const std::unordered_set<OatQuickMethodHeader*>& method_headers)
       REQUIRES(!lock_)
       REQUIRES(!Locks::cha_lock_);

   // Removes method from the cache. The caller must ensure that all threads
   // are suspended and the method should not be in any thread's stack.
   bool RemoveMethodLocked(ArtMethod* method, bool release_memory)
       REQUIRES(lock_)
       REQUIRES(Locks::mutator_lock_);

   // Free code and data allocations for `code_ptr`.
   void FreeCodeAndData(const void* code_ptr) REQUIRES(lock_);

   // Number of bytes allocated in the code cache.
   size_t CodeCacheSizeLocked() REQUIRES(lock_);

   // Number of bytes allocated in the data cache.
   size_t DataCacheSizeLocked() REQUIRES(lock_);

   // Notify all waiting threads that a collection is done.
   void NotifyCollectionDone(Thread* self) REQUIRES(lock_);

   // Try to increase the current capacity of the code cache. Return whether we
   // succeeded at doing so.
   bool IncreaseCodeCacheCapacity() REQUIRES(lock_);

   // Set the footprint limit of the code cache.
   void SetFootprintLimit(size_t new_footprint) REQUIRES(lock_);

   // Return whether we should do a full collection given the current state of the cache.
   bool ShouldDoFullCollection()
       REQUIRES(lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   void DoCollection(Thread* self, bool collect_profiling_info)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   void RemoveUnmarkedCode(Thread* self)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   void MarkCompiledCodeOnThreadStacks(Thread* self)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   bool CheckLiveCompiledCodeHasProfilingInfo()
       REQUIRES(lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   uint8_t* AllocateCode(size_t code_size) REQUIRES(lock_);
   void FreeCode(uint8_t* code) REQUIRES(lock_);
   uint8_t* AllocateData(size_t data_size) REQUIRES(lock_);
   void FreeData(uint8_t* data) REQUIRES(lock_);

   bool IsWeakAccessEnabled(Thread* self) const;
   void WaitUntilInlineCacheAccessible(Thread* self)
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);

   class JniStubKey;
   class JniStubData;

   // Lock for guarding allocations, collections, and the method_code_map_.
   Mutex lock_ BOTTOM_MUTEX_ACQUIRED_AFTER;
   // Condition to wait on during collection.
   ConditionVariable lock_cond_ GUARDED_BY(lock_);
   // Whether there is a code cache collection in progress.
   bool collection_in_progress_ GUARDED_BY(lock_);
   // Mem map which holds code.
   std::unique_ptr<MemMap> code_map_;
   // Mem map which holds data (stack maps and profiling info).
   std::unique_ptr<MemMap> data_map_;
   // The opaque mspace for allocating code.
   void* code_mspace_ GUARDED_BY(lock_);
   // The opaque mspace for allocating data.
   void* data_mspace_ GUARDED_BY(lock_);
   // Bitmap for collecting code and data.
   std::unique_ptr<CodeCacheBitmap> live_bitmap_;
   // Holds compiled code associated with the shorty for a JNI stub.
   SafeMap<JniStubKey, JniStubData> jni_stubs_map_ GUARDED_BY(lock_);
   // Holds compiled code associated to the ArtMethod.
   SafeMap<const void*, ArtMethod*> method_code_map_ GUARDED_BY(lock_);
   // Holds osr compiled code associated to the ArtMethod.
   SafeMap<ArtMethod*, const void*> osr_code_map_ GUARDED_BY(lock_);
   // ProfilingInfo objects we have allocated.
   std::vector<ProfilingInfo*> profiling_infos_ GUARDED_BY(lock_);

   // The maximum capacity in bytes this code cache can go to.
   size_t max_capacity_ GUARDED_BY(lock_);

   // The current capacity in bytes of the code cache.
   size_t current_capacity_ GUARDED_BY(lock_);

   // The current footprint in bytes of the code portion of the code cache.
   size_t code_end_ GUARDED_BY(lock_);

   // The current footprint in bytes of the data portion of the code cache.
   size_t data_end_ GUARDED_BY(lock_);

   // Whether the last collection round increased the code cache.
   bool last_collection_increased_code_cache_ GUARDED_BY(lock_);

   // Whether we can do garbage collection. Not 'const' as tests may override this.
   bool garbage_collect_code_;

   // The size in bytes of used memory for the data portion of the code cache.
   size_t used_memory_for_data_ GUARDED_BY(lock_);

   // The size in bytes of used memory for the code portion of the code cache.
   size_t used_memory_for_code_ GUARDED_BY(lock_);

   // Number of compilations done throughout the lifetime of the JIT.
   size_t number_of_compilations_ GUARDED_BY(lock_);

   // Number of compilations for on-stack-replacement done throughout the lifetime of the JIT.
   size_t number_of_osr_compilations_ GUARDED_BY(lock_);

   // Number of code cache collections done throughout the lifetime of the JIT.
   size_t number_of_collections_ GUARDED_BY(lock_);

   // Histograms for keeping track of stack map size statistics.
   Histogram<uint64_t> histogram_stack_map_memory_use_ GUARDED_BY(lock_);

   // Histograms for keeping track of code size statistics.
   Histogram<uint64_t> histogram_code_memory_use_ GUARDED_BY(lock_);

   // Histograms for keeping track of profiling info statistics.
   Histogram<uint64_t> histogram_profiling_info_memory_use_ GUARDED_BY(lock_);

   // Whether the GC allows accessing weaks in inline caches. Note that this
   // is not used by the concurrent collector, which uses
   // Thread::SetWeakRefAccessEnabled instead.
   Atomic<bool> is_weak_access_enabled_;

   // Condition to wait on for accessing inline caches.
   ConditionVariable inline_cache_cond_ GUARDED_BY(lock_);

   // Mapping flags for the code section.
   const int memmap_flags_prot_code_;

   friend class art::JitJniStubTestHelper;
   friend class ScopedCodeCacheWrite;

   DISALLOW_IMPLICIT_CONSTRUCTORS(JitCodeCache);
 };

 }  // namespace jit
 }  // namespace art

 #endif  // ART_RUNTIME_JIT_JIT_CODE_CACHE_H_
	/*
	* Copyright 2014 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.
	*/

	#ifndef ART_RUNTIME_JIT_JIT_CODE_CACHE_H_
	#define ART_RUNTIME_JIT_JIT_CODE_CACHE_H_

	#include <iosfwd>
	#include <memory>
	#include <set>
	#include <string>
	#include <unordered_set>
	#include <vector>

	#include "base/arena_containers.h"
	#include "base/atomic.h"
	#include "base/histogram.h"
	#include "base/macros.h"
	#include "base/mutex.h"
	#include "base/safe_map.h"

	namespace art {

	class ArtMethod;
	template<class T> class Handle;
	class LinearAlloc;
	class InlineCache;
	class IsMarkedVisitor;
	class JitJniStubTestHelper;
	class MemMap;
	class OatQuickMethodHeader;
	struct ProfileMethodInfo;
	class ProfilingInfo;
	class Thread;

	namespace gc {
	namespace accounting {
	template<size_t kAlignment> class MemoryRangeBitmap;
	} // namespace accounting
	} // namespace gc

	namespace mirror {
	class Class;
	class Object;
	template<class T> class ObjectArray;
	} // namespace mirror

	namespace gc {
	namespace accounting {
	template<size_t kAlignment> class MemoryRangeBitmap;
	} // namespace accounting
	} // namespace gc

	namespace mirror {
	class Class;
	class Object;
	template<class T> class ObjectArray;
	} // namespace mirror

	namespace jit {

	class JitInstrumentationCache;
	class ScopedCodeCacheWrite;

	// Alignment in bits that will suit all architectures.
	static constexpr int kJitCodeAlignment = 16;
	using CodeCacheBitmap = gc::accounting::MemoryRangeBitmap<kJitCodeAlignment>;

	class JitCodeCache {
	public:
	static constexpr size_t kMaxCapacity = 64 * MB;
	// Put the default to a very low amount for debug builds to stress the code cache
	// collection.
	static constexpr size_t kInitialCapacity = kIsDebugBuild ? 8 * KB : 64 * KB;

	// By default, do not GC until reaching 256KB.
	static constexpr size_t kReservedCapacity = kInitialCapacity * 4;

	// Create the code cache with a code + data capacity equal to "capacity", error message is passed
	// in the out arg error_msg.
	static JitCodeCache* Create(size_t initial_capacity,
	size_t max_capacity,
	bool generate_debug_info,
	bool used_only_for_profile_data,
	std::string* error_msg);
	~JitCodeCache();

	// Number of bytes allocated in the code cache.
	size_t CodeCacheSize() REQUIRES(!lock_);

	// Number of bytes allocated in the data cache.
	size_t DataCacheSize() REQUIRES(!lock_);

	bool NotifyCompilationOf(ArtMethod* method, Thread* self, bool osr)
	REQUIRES_SHARED(Locks::mutator_lock_)
	REQUIRES(!lock_);

	void NotifyMethodRedefined(ArtMethod* method)
	REQUIRES(Locks::mutator_lock_)
	REQUIRES(!lock_);

	// Notify to the code cache that the compiler wants to use the
	// profiling info of `method` to drive optimizations,
	// and therefore ensure the returned profiling info object is not
	// collected.
	ProfilingInfo* NotifyCompilerUse(ArtMethod* method, Thread* self)
	REQUIRES_SHARED(Locks::mutator_lock_)
	REQUIRES(!lock_);

	void DoneCompiling(ArtMethod* method, Thread* self, bool osr)
	REQUIRES_SHARED(Locks::mutator_lock_)
	REQUIRES(!lock_);

	void DoneCompilerUse(ArtMethod* method, Thread* self)
	REQUIRES_SHARED(Locks::mutator_lock_)
	REQUIRES(!lock_);

	// Allocate and write code and its metadata to the code cache.
	// `cha_single_implementation_list` needs to be registered via CHA (if it's
	// still valid), since the compiled code still needs to be invalidated if the
	// single-implementation assumptions are violated later. This needs to be done
	// even if `has_should_deoptimize_flag` is false, which can happen due to CHA
	// guard elimination.
	uint8_t* CommitCode(Thread* self,
	ArtMethod* method,
	uint8_t* stack_map,
	uint8_t* roots_data,
	const uint8_t* code,
	size_t code_size,
	size_t data_size,
	bool osr,
	Handle<mirror::ObjectArray<mirror::Object>> roots,
	bool has_should_deoptimize_flag,
	const ArenaSet<ArtMethod*>& cha_single_implementation_list)
	REQUIRES_SHARED(Locks::mutator_lock_)
	REQUIRES(!lock_);

	// Return true if the code cache contains this pc.
	bool ContainsPc(const void* pc) const;

	// Returns true if either the method's entrypoint is JIT compiled code or it is the
	// instrumentation entrypoint and we can jump to jit code for this method. For testing use only.
	bool WillExecuteJitCode(ArtMethod* method) REQUIRES(!lock_);

	// Return true if the code cache contains this method.
	bool ContainsMethod(ArtMethod* method) REQUIRES(!lock_);

	// Return the code pointer for a JNI-compiled stub if the method is in the cache, null otherwise.
	const void* GetJniStubCode(ArtMethod* method) REQUIRES(!lock_);

	// Allocate a region of data that contain `size` bytes, and potentially space
	// for storing `number_of_roots` roots. Returns null if there is no more room.
	// Return the number of bytes allocated.
	size_t ReserveData(Thread* self,
	size_t stack_map_size,
	size_t number_of_roots,
	ArtMethod* method,
	uint8_t** stack_map_data,
	uint8_t** roots_data)
	REQUIRES_SHARED(Locks::mutator_lock_)
	REQUIRES(!lock_);

	// Clear data from the data portion of the code cache.
	void ClearData(Thread* self, uint8_t* stack_map_data, uint8_t* roots_data)
	REQUIRES_SHARED(Locks::mutator_lock_)
	REQUIRES(!lock_);

	CodeCacheBitmap* GetLiveBitmap() const {
	return live_bitmap_.get();
	}

	// Perform a collection on the code cache.
	void GarbageCollectCache(Thread* self)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	// Given the 'pc', try to find the JIT compiled code associated with it.
	// Return null if 'pc' is not in the code cache. 'method' is passed for
	// sanity check.
	OatQuickMethodHeader* LookupMethodHeader(uintptr_t pc, ArtMethod* method)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	OatQuickMethodHeader* LookupOsrMethodHeader(ArtMethod* method)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	// Removes method from the cache for testing purposes. The caller
	// must ensure that all threads are suspended and the method should
	// not be in any thread's stack.
	bool RemoveMethod(ArtMethod* method, bool release_memory)
	REQUIRES(!lock_)
	REQUIRES(Locks::mutator_lock_);

	// Remove all methods in our cache that were allocated by 'alloc'.
	void RemoveMethodsIn(Thread* self, const LinearAlloc& alloc)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	void CopyInlineCacheInto(const InlineCache& ic, Handle<mirror::ObjectArray<mirror::Class>> array)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	// Create a 'ProfileInfo' for 'method'. If 'retry_allocation' is true,
	// will collect and retry if the first allocation is unsuccessful.
	ProfilingInfo* AddProfilingInfo(Thread* self,
	ArtMethod* method,
	const std::vector<uint32_t>& entries,
	bool retry_allocation)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	bool OwnsSpace(const void* mspace) const NO_THREAD_SAFETY_ANALYSIS {
	return mspace == code_mspace_ \|\| mspace == data_mspace_;
	}

	void* MoreCore(const void* mspace, intptr_t increment);

	// Adds to `methods` all profiled methods which are part of any of the given dex locations.
	void GetProfiledMethods(const std::set<std::string>& dex_base_locations,
	std::vector<ProfileMethodInfo>& methods)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	uint64_t GetLastUpdateTimeNs() const;

	size_t GetMemorySizeOfCodePointer(const void* ptr) REQUIRES(!lock_);

	void InvalidateCompiledCodeFor(ArtMethod* method, const OatQuickMethodHeader* code)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	void Dump(std::ostream& os) REQUIRES(!lock_);

	bool IsOsrCompiled(ArtMethod* method) REQUIRES(!lock_);

	void SweepRootTables(IsMarkedVisitor* visitor)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	// The GC needs to disallow the reading of inline caches when it processes them,
	// to avoid having a class being used while it is being deleted.
	void AllowInlineCacheAccess() REQUIRES(!lock_);
	void DisallowInlineCacheAccess() REQUIRES(!lock_);
	void BroadcastForInlineCacheAccess() REQUIRES(!lock_);

	// Notify the code cache that the method at the pointer 'old_method' is being moved to the pointer
	// 'new_method' since it is being made obsolete.
	void MoveObsoleteMethod(ArtMethod* old_method, ArtMethod* new_method)
	REQUIRES(!lock_) REQUIRES(Locks::mutator_lock_);

	// Dynamically change whether we want to garbage collect code. Should only be used
	// by tests.
	void SetGarbageCollectCode(bool value) {
	garbage_collect_code_ = value;
	}

	bool GetGarbageCollectCode() const {
	return garbage_collect_code_;
	}

	// If Jit-gc has been disabled (and instrumentation has been enabled) this will return the
	// jit-compiled entrypoint for this method. Otherwise it will return null.
	const void* FindCompiledCodeForInstrumentation(ArtMethod* method)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	private:
	// Take ownership of maps.
	JitCodeCache(MemMap* code_map,
	MemMap* data_map,
	size_t initial_code_capacity,
	size_t initial_data_capacity,
	size_t max_capacity,
	bool garbage_collect_code,
	int memmap_flags_prot_code);

	// Internal version of 'CommitCode' that will not retry if the
	// allocation fails. Return null if the allocation fails.
	uint8_t* CommitCodeInternal(Thread* self,
	ArtMethod* method,
	uint8_t* stack_map,
	uint8_t* roots_data,
	const uint8_t* code,
	size_t code_size,
	size_t data_size,
	bool osr,
	Handle<mirror::ObjectArray<mirror::Object>> roots,
	bool has_should_deoptimize_flag,
	const ArenaSet<ArtMethod*>& cha_single_implementation_list)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	// Adds the given roots to the roots_data. Only a member for annotalysis.
	void FillRootTable(uint8_t* roots_data, Handle<mirror::ObjectArray<mirror::Object>> roots)
	REQUIRES(lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	ProfilingInfo* AddProfilingInfoInternal(Thread* self,
	ArtMethod* method,
	const std::vector<uint32_t>& entries)
	REQUIRES(lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	// If a collection is in progress, wait for it to finish. Return
	// whether the thread actually waited.
	bool WaitForPotentialCollectionToComplete(Thread* self)
	REQUIRES(lock_) REQUIRES(!Locks::mutator_lock_);

	// Remove CHA dependents and underlying allocations for entries in `method_headers`.
	void FreeAllMethodHeaders(const std::unordered_set<OatQuickMethodHeader*>& method_headers)
	REQUIRES(!lock_)
	REQUIRES(!Locks::cha_lock_);

	// Removes method from the cache. The caller must ensure that all threads
	// are suspended and the method should not be in any thread's stack.
	bool RemoveMethodLocked(ArtMethod* method, bool release_memory)
	REQUIRES(lock_)
	REQUIRES(Locks::mutator_lock_);

	// Free code and data allocations for `code_ptr`.
	void FreeCodeAndData(const void* code_ptr) REQUIRES(lock_);

	// Number of bytes allocated in the code cache.
	size_t CodeCacheSizeLocked() REQUIRES(lock_);

	// Number of bytes allocated in the data cache.
	size_t DataCacheSizeLocked() REQUIRES(lock_);

	// Notify all waiting threads that a collection is done.
	void NotifyCollectionDone(Thread* self) REQUIRES(lock_);

	// Try to increase the current capacity of the code cache. Return whether we
	// succeeded at doing so.
	bool IncreaseCodeCacheCapacity() REQUIRES(lock_);

	// Set the footprint limit of the code cache.
	void SetFootprintLimit(size_t new_footprint) REQUIRES(lock_);

	// Return whether we should do a full collection given the current state of the cache.
	bool ShouldDoFullCollection()
	REQUIRES(lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	void DoCollection(Thread* self, bool collect_profiling_info)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	void RemoveUnmarkedCode(Thread* self)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	void MarkCompiledCodeOnThreadStacks(Thread* self)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	bool CheckLiveCompiledCodeHasProfilingInfo()
	REQUIRES(lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	uint8_t* AllocateCode(size_t code_size) REQUIRES(lock_);
	void FreeCode(uint8_t* code) REQUIRES(lock_);
	uint8_t* AllocateData(size_t data_size) REQUIRES(lock_);
	void FreeData(uint8_t* data) REQUIRES(lock_);

	bool IsWeakAccessEnabled(Thread* self) const;
	void WaitUntilInlineCacheAccessible(Thread* self)
	REQUIRES(!lock_)
	REQUIRES_SHARED(Locks::mutator_lock_);

	class JniStubKey;
	class JniStubData;

	// Lock for guarding allocations, collections, and the method_code_map_.
	Mutex lock_ BOTTOM_MUTEX_ACQUIRED_AFTER;
	// Condition to wait on during collection.
	ConditionVariable lock_cond_ GUARDED_BY(lock_);
	// Whether there is a code cache collection in progress.
	bool collection_in_progress_ GUARDED_BY(lock_);
	// Mem map which holds code.
	std::unique_ptr<MemMap> code_map_;
	// Mem map which holds data (stack maps and profiling info).
	std::unique_ptr<MemMap> data_map_;
	// The opaque mspace for allocating code.
	void* code_mspace_ GUARDED_BY(lock_);
	// The opaque mspace for allocating data.
	void* data_mspace_ GUARDED_BY(lock_);
	// Bitmap for collecting code and data.
	std::unique_ptr<CodeCacheBitmap> live_bitmap_;
	// Holds compiled code associated with the shorty for a JNI stub.
	SafeMap<JniStubKey, JniStubData> jni_stubs_map_ GUARDED_BY(lock_);
	// Holds compiled code associated to the ArtMethod.
	SafeMap<const void, ArtMethod> method_code_map_ GUARDED_BY(lock_);
	// Holds osr compiled code associated to the ArtMethod.
	SafeMap<ArtMethod, const void> osr_code_map_ GUARDED_BY(lock_);
	// ProfilingInfo objects we have allocated.
	std::vector<ProfilingInfo*> profiling_infos_ GUARDED_BY(lock_);

	// The maximum capacity in bytes this code cache can go to.
	size_t max_capacity_ GUARDED_BY(lock_);

	// The current capacity in bytes of the code cache.
	size_t current_capacity_ GUARDED_BY(lock_);

	// The current footprint in bytes of the code portion of the code cache.
	size_t code_end_ GUARDED_BY(lock_);

	// The current footprint in bytes of the data portion of the code cache.
	size_t data_end_ GUARDED_BY(lock_);

	// Whether the last collection round increased the code cache.
	bool last_collection_increased_code_cache_ GUARDED_BY(lock_);

	// Whether we can do garbage collection. Not 'const' as tests may override this.
	bool garbage_collect_code_;

	// The size in bytes of used memory for the data portion of the code cache.
	size_t used_memory_for_data_ GUARDED_BY(lock_);

	// The size in bytes of used memory for the code portion of the code cache.
	size_t used_memory_for_code_ GUARDED_BY(lock_);

	// Number of compilations done throughout the lifetime of the JIT.
	size_t number_of_compilations_ GUARDED_BY(lock_);

	// Number of compilations for on-stack-replacement done throughout the lifetime of the JIT.
	size_t number_of_osr_compilations_ GUARDED_BY(lock_);

	// Number of code cache collections done throughout the lifetime of the JIT.
	size_t number_of_collections_ GUARDED_BY(lock_);

	// Histograms for keeping track of stack map size statistics.
	Histogram<uint64_t> histogram_stack_map_memory_use_ GUARDED_BY(lock_);

	// Histograms for keeping track of code size statistics.
	Histogram<uint64_t> histogram_code_memory_use_ GUARDED_BY(lock_);

	// Histograms for keeping track of profiling info statistics.
	Histogram<uint64_t> histogram_profiling_info_memory_use_ GUARDED_BY(lock_);

	// Whether the GC allows accessing weaks in inline caches. Note that this
	// is not used by the concurrent collector, which uses
	// Thread::SetWeakRefAccessEnabled instead.
	Atomic<bool> is_weak_access_enabled_;

	// Condition to wait on for accessing inline caches.
	ConditionVariable inline_cache_cond_ GUARDED_BY(lock_);

	// Mapping flags for the code section.
	const int memmap_flags_prot_code_;

	friend class art::JitJniStubTestHelper;
	friend class ScopedCodeCacheWrite;

	DISALLOW_IMPLICIT_CONSTRUCTORS(JitCodeCache);
	};

	} // namespace jit
	} // namespace art

	#endif // ART_RUNTIME_JIT_JIT_CODE_CACHE_H_