compiler/optimizing/intrinsics.cc - LeafOS-Project/android_art - Gitiles

 /*
  * Copyright (C) 2015 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 "intrinsics.h"

 #include "art_field-inl.h"
 #include "art_method-inl.h"
 #include "base/utils.h"
 #include "class_linker.h"
 #include "class_root.h"
 #include "dex/invoke_type.h"
 #include "driver/compiler_options.h"
 #include "gc/space/image_space.h"
 #include "image-inl.h"
 #include "intrinsic_objects.h"
 #include "nodes.h"
 #include "obj_ptr-inl.h"
 #include "scoped_thread_state_change-inl.h"
 #include "thread-current-inl.h"

 namespace art {

 std::ostream& operator<<(std::ostream& os, const Intrinsics& intrinsic) {
   switch (intrinsic) {
     case Intrinsics::kNone:
       os << "None";
       break;
 #define OPTIMIZING_INTRINSICS(Name, IsStatic, NeedsEnvironmentOrCache, SideEffects, Exceptions, ...) \
     case Intrinsics::k ## Name: \
       os << # Name; \
       break;
 #include "intrinsics_list.h"
       INTRINSICS_LIST(OPTIMIZING_INTRINSICS)
 #undef STATIC_INTRINSICS_LIST
 #undef VIRTUAL_INTRINSICS_LIST
 #undef OPTIMIZING_INTRINSICS
   }
   return os;
 }

 static const char kIntegerCacheDescriptor[] = "Ljava/lang/Integer$IntegerCache;";
 static const char kIntegerDescriptor[] = "Ljava/lang/Integer;";
 static const char kIntegerArrayDescriptor[] = "[Ljava/lang/Integer;";
 static const char kLowFieldName[] = "low";
 static const char kHighFieldName[] = "high";
 static const char kValueFieldName[] = "value";

 static ObjPtr<mirror::ObjectArray<mirror::Object>> GetBootImageLiveObjects()
     REQUIRES_SHARED(Locks::mutator_lock_) {
   gc::Heap* heap = Runtime::Current()->GetHeap();
   const std::vector<gc::space::ImageSpace*>& boot_image_spaces = heap->GetBootImageSpaces();
   DCHECK(!boot_image_spaces.empty());
   const ImageHeader& main_header = boot_image_spaces[0]->GetImageHeader();
   ObjPtr<mirror::ObjectArray<mirror::Object>> boot_image_live_objects =
       ObjPtr<mirror::ObjectArray<mirror::Object>>::DownCast(
           main_header.GetImageRoot<kWithoutReadBarrier>(ImageHeader::kBootImageLiveObjects));
   DCHECK(boot_image_live_objects != nullptr);
   DCHECK(heap->ObjectIsInBootImageSpace(boot_image_live_objects));
   return boot_image_live_objects;
 }

 static ObjPtr<mirror::Class> LookupInitializedClass(Thread* self,
                                                     ClassLinker* class_linker,
                                                     const char* descriptor)
         REQUIRES_SHARED(Locks::mutator_lock_) {
   ObjPtr<mirror::Class> klass =
       class_linker->LookupClass(self, descriptor, /* class_loader= */ nullptr);
   DCHECK(klass != nullptr);
   DCHECK(klass->IsInitialized());
   return klass;
 }

 static ObjPtr<mirror::ObjectArray<mirror::Object>> GetIntegerCacheArray(
     ObjPtr<mirror::Class> cache_class) REQUIRES_SHARED(Locks::mutator_lock_) {
   ArtField* cache_field = cache_class->FindDeclaredStaticField("cache", kIntegerArrayDescriptor);
   DCHECK(cache_field != nullptr);
   return ObjPtr<mirror::ObjectArray<mirror::Object>>::DownCast(cache_field->GetObject(cache_class));
 }

 static int32_t GetIntegerCacheField(ObjPtr<mirror::Class> cache_class, const char* field_name)
     REQUIRES_SHARED(Locks::mutator_lock_) {
   ArtField* field = cache_class->FindDeclaredStaticField(field_name, "I");
   DCHECK(field != nullptr);
   return field->GetInt(cache_class);
 }

 static bool CheckIntegerCache(Thread* self,
                               ClassLinker* class_linker,
                               ObjPtr<mirror::ObjectArray<mirror::Object>> boot_image_live_objects,
                               ObjPtr<mirror::ObjectArray<mirror::Object>> boot_image_cache)
     REQUIRES_SHARED(Locks::mutator_lock_) {
   DCHECK(boot_image_cache != nullptr);

   // Since we have a cache in the boot image, both java.lang.Integer and
   // java.lang.Integer$IntegerCache must be initialized in the boot image.
   ObjPtr<mirror::Class> cache_class =
       LookupInitializedClass(self, class_linker, kIntegerCacheDescriptor);
   ObjPtr<mirror::Class> integer_class =
       LookupInitializedClass(self, class_linker, kIntegerDescriptor);

   // Check that the current cache is the same as the `boot_image_cache`.
   ObjPtr<mirror::ObjectArray<mirror::Object>> current_cache = GetIntegerCacheArray(cache_class);
   if (current_cache != boot_image_cache) {
     return false;  // Messed up IntegerCache.cache.
   }

   // Check that the range matches the boot image cache length.
   int32_t low = GetIntegerCacheField(cache_class, kLowFieldName);
   int32_t high = GetIntegerCacheField(cache_class, kHighFieldName);
   if (boot_image_cache->GetLength() != high - low + 1) {
     return false;  // Messed up IntegerCache.low or IntegerCache.high.
   }

   // Check that the elements match the boot image intrinsic objects and check their values as well.
   ArtField* value_field = integer_class->FindDeclaredInstanceField(kValueFieldName, "I");
   DCHECK(value_field != nullptr);
   for (int32_t i = 0, len = boot_image_cache->GetLength(); i != len; ++i) {
     ObjPtr<mirror::Object> boot_image_object =
         IntrinsicObjects::GetIntegerValueOfObject(boot_image_live_objects, i);
     DCHECK(Runtime::Current()->GetHeap()->ObjectIsInBootImageSpace(boot_image_object));
     // No need for read barrier for comparison with a boot image object.
     ObjPtr<mirror::Object> current_object =
         boot_image_cache->GetWithoutChecks<kVerifyNone, kWithoutReadBarrier>(i);
     if (boot_image_object != current_object) {
       return false;  // Messed up IntegerCache.cache[i]
     }
     if (value_field->GetInt(boot_image_object) != low + i) {
       return false;  // Messed up IntegerCache.cache[i].value.
     }
   }

   return true;
 }

 void IntrinsicVisitor::ComputeIntegerValueOfLocations(HInvoke* invoke,
                                                       CodeGenerator* codegen,
                                                       Location return_location,
                                                       Location first_argument_location) {
   // The intrinsic will call if it needs to allocate a j.l.Integer.
   LocationSummary::CallKind call_kind = LocationSummary::kCallOnMainOnly;
   const CompilerOptions& compiler_options = codegen->GetCompilerOptions();
   if (compiler_options.IsBootImage()) {
     // Piggyback on the method load kind to determine whether we can use PC-relative addressing.
     // This should cover both the testing config (non-PIC boot image) and codegens that reject
     // PC-relative load kinds and fall back to the runtime call.
     if (!invoke->AsInvokeStaticOrDirect()->HasPcRelativeMethodLoadKind()) {
       return;
     }
     if (!compiler_options.IsImageClass(kIntegerCacheDescriptor) ||
         !compiler_options.IsImageClass(kIntegerDescriptor)) {
       return;
     }
     ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
     Thread* self = Thread::Current();
     ScopedObjectAccess soa(self);
     ObjPtr<mirror::Class> cache_class = class_linker->LookupClass(
         self, kIntegerCacheDescriptor, /* class_loader= */ nullptr);
     DCHECK(cache_class != nullptr);
     if (UNLIKELY(!cache_class->IsInitialized())) {
       LOG(WARNING) << "Image class " << cache_class->PrettyDescriptor() << " is uninitialized.";
       return;
     }
     ObjPtr<mirror::Class> integer_class =
         class_linker->LookupClass(self, kIntegerDescriptor, /* class_loader= */ nullptr);
     DCHECK(integer_class != nullptr);
     if (UNLIKELY(!integer_class->IsInitialized())) {
       LOG(WARNING) << "Image class " << integer_class->PrettyDescriptor() << " is uninitialized.";
       return;
     }
     int32_t low = GetIntegerCacheField(cache_class, kLowFieldName);
     int32_t high = GetIntegerCacheField(cache_class, kHighFieldName);
     if (kIsDebugBuild) {
       ObjPtr<mirror::ObjectArray<mirror::Object>> current_cache = GetIntegerCacheArray(cache_class);
       CHECK(current_cache != nullptr);
       CHECK_EQ(current_cache->GetLength(), high - low + 1);
       ArtField* value_field = integer_class->FindDeclaredInstanceField(kValueFieldName, "I");
       CHECK(value_field != nullptr);
       for (int32_t i = 0, len = current_cache->GetLength(); i != len; ++i) {
         ObjPtr<mirror::Object> current_object = current_cache->GetWithoutChecks(i);
         CHECK(current_object != nullptr);
         CHECK_EQ(value_field->GetInt(current_object), low + i);
       }
     }
     if (invoke->InputAt(0)->IsIntConstant()) {
       int32_t value = invoke->InputAt(0)->AsIntConstant()->GetValue();
       if (static_cast<uint32_t>(value) - static_cast<uint32_t>(low) <
           static_cast<uint32_t>(high - low + 1)) {
         // No call, we shall use direct pointer to the Integer object.
         call_kind = LocationSummary::kNoCall;
       }
     }
   } else {
     Runtime* runtime = Runtime::Current();
     if (runtime->GetHeap()->GetBootImageSpaces().empty()) {
       return;  // Running without boot image, cannot use required boot image objects.
     }
     Thread* self = Thread::Current();
     ScopedObjectAccess soa(self);
     ObjPtr<mirror::ObjectArray<mirror::Object>> boot_image_live_objects = GetBootImageLiveObjects();
     ObjPtr<mirror::ObjectArray<mirror::Object>> cache =
         IntrinsicObjects::GetIntegerValueOfCache(boot_image_live_objects);
     if (cache == nullptr) {
       return;  // No cache in the boot image.
     }
     if (runtime->UseJitCompilation()) {
       if (!CheckIntegerCache(self, runtime->GetClassLinker(), boot_image_live_objects, cache)) {
         return;  // The cache was somehow messed up, probably by using reflection.
       }
     } else {
       DCHECK(runtime->IsAotCompiler());
       DCHECK(CheckIntegerCache(self, runtime->GetClassLinker(), boot_image_live_objects, cache));
       if (invoke->InputAt(0)->IsIntConstant()) {
         int32_t value = invoke->InputAt(0)->AsIntConstant()->GetValue();
         // Retrieve the `value` from the lowest cached Integer.
         ObjPtr<mirror::Object> low_integer =
             IntrinsicObjects::GetIntegerValueOfObject(boot_image_live_objects, 0u);
         ObjPtr<mirror::Class> integer_class =
             low_integer->GetClass<kVerifyNone, kWithoutReadBarrier>();
         ArtField* value_field = integer_class->FindDeclaredInstanceField(kValueFieldName, "I");
         DCHECK(value_field != nullptr);
         int32_t low = value_field->GetInt(low_integer);
         if (static_cast<uint32_t>(value) - static_cast<uint32_t>(low) <
             static_cast<uint32_t>(cache->GetLength())) {
           // No call, we shall use direct pointer to the Integer object. Note that we cannot
           // do this for JIT as the "low" can change through reflection before emitting the code.
           call_kind = LocationSummary::kNoCall;
         }
       }
     }
   }

   ArenaAllocator* allocator = invoke->GetBlock()->GetGraph()->GetAllocator();
   LocationSummary* locations = new (allocator) LocationSummary(invoke, call_kind, kIntrinsified);
   if (call_kind == LocationSummary::kCallOnMainOnly) {
     locations->SetInAt(0, Location::RegisterOrConstant(invoke->InputAt(0)));
     locations->AddTemp(first_argument_location);
     locations->SetOut(return_location);
   } else {
     locations->SetInAt(0, Location::ConstantLocation(invoke->InputAt(0)->AsConstant()));
     locations->SetOut(Location::RequiresRegister());
   }
 }

 static int32_t GetIntegerCacheLowFromIntegerCache(Thread* self, ClassLinker* class_linker)
     REQUIRES_SHARED(Locks::mutator_lock_) {
   ObjPtr<mirror::Class> cache_class =
       LookupInitializedClass(self, class_linker, kIntegerCacheDescriptor);
   return GetIntegerCacheField(cache_class, kLowFieldName);
 }

 static uint32_t CalculateBootImageOffset(ObjPtr<mirror::Object> object)
     REQUIRES_SHARED(Locks::mutator_lock_) {
   gc::Heap* heap = Runtime::Current()->GetHeap();
   DCHECK(heap->ObjectIsInBootImageSpace(object));
   return reinterpret_cast<const uint8_t*>(object.Ptr()) - heap->GetBootImageSpaces()[0]->Begin();
 }

 inline IntrinsicVisitor::IntegerValueOfInfo::IntegerValueOfInfo()
     : value_offset(0),
       low(0),
       length(0u),
       integer_boot_image_offset(kInvalidReference),
       value_boot_image_reference(kInvalidReference) {}

 IntrinsicVisitor::IntegerValueOfInfo IntrinsicVisitor::ComputeIntegerValueOfInfo(
     HInvoke* invoke, const CompilerOptions& compiler_options) {
   // Note that we could cache all of the data looked up here. but there's no good
   // location for it. We don't want to add it to WellKnownClasses, to avoid creating global
   // jni values. Adding it as state to the compiler singleton seems like wrong
   // separation of concerns.
   // The need for this data should be pretty rare though.

   // Note that at this point we can no longer abort the code generation. Therefore,
   // we need to provide data that shall not lead to a crash even if the fields were
   // modified through reflection since ComputeIntegerValueOfLocations() when JITting.

   Runtime* runtime = Runtime::Current();
   ClassLinker* class_linker = runtime->GetClassLinker();
   Thread* self = Thread::Current();
   ScopedObjectAccess soa(self);

   IntegerValueOfInfo info;
   if (compiler_options.IsBootImage()) {
     ObjPtr<mirror::Class> integer_class =
         LookupInitializedClass(self, class_linker, kIntegerDescriptor);
     ArtField* value_field = integer_class->FindDeclaredInstanceField(kValueFieldName, "I");
     DCHECK(value_field != nullptr);
     info.value_offset = value_field->GetOffset().Uint32Value();
     ObjPtr<mirror::Class> cache_class =
         LookupInitializedClass(self, class_linker, kIntegerCacheDescriptor);
     info.low = GetIntegerCacheField(cache_class, kLowFieldName);
     int32_t high = GetIntegerCacheField(cache_class, kHighFieldName);
     info.length = dchecked_integral_cast<uint32_t>(high - info.low + 1);

     info.integer_boot_image_offset = IntegerValueOfInfo::kInvalidReference;
     if (invoke->InputAt(0)->IsIntConstant()) {
       int32_t input_value = invoke->InputAt(0)->AsIntConstant()->GetValue();
       uint32_t index = static_cast<uint32_t>(input_value) - static_cast<uint32_t>(info.low);
       if (index < static_cast<uint32_t>(info.length)) {
         info.value_boot_image_reference = IntrinsicObjects::EncodePatch(
             IntrinsicObjects::PatchType::kIntegerValueOfObject, index);
       } else {
         // Not in the cache.
         info.value_boot_image_reference = IntegerValueOfInfo::kInvalidReference;
       }
     } else {
       info.array_data_boot_image_reference =
           IntrinsicObjects::EncodePatch(IntrinsicObjects::PatchType::kIntegerValueOfArray);
     }
   } else {
     ObjPtr<mirror::ObjectArray<mirror::Object>> boot_image_live_objects = GetBootImageLiveObjects();
     ObjPtr<mirror::Object> low_integer =
         IntrinsicObjects::GetIntegerValueOfObject(boot_image_live_objects, 0u);
     ObjPtr<mirror::Class> integer_class = low_integer->GetClass<kVerifyNone, kWithoutReadBarrier>();
     ArtField* value_field = integer_class->FindDeclaredInstanceField(kValueFieldName, "I");
     DCHECK(value_field != nullptr);
     info.value_offset = value_field->GetOffset().Uint32Value();
     if (runtime->UseJitCompilation()) {
       // Use the current `IntegerCache.low` for JIT to avoid truly surprising behavior if the
       // code messes up the `value` field in the lowest cached Integer using reflection.
       info.low = GetIntegerCacheLowFromIntegerCache(self, class_linker);
     } else {
       // For app AOT, the `low_integer->value` should be the same as `IntegerCache.low`.
       info.low = value_field->GetInt(low_integer);
       DCHECK_EQ(info.low, GetIntegerCacheLowFromIntegerCache(self, class_linker));
     }
     // Do not look at `IntegerCache.high`, use the immutable length of the cache array instead.
     info.length = dchecked_integral_cast<uint32_t>(
         IntrinsicObjects::GetIntegerValueOfCache(boot_image_live_objects)->GetLength());

     info.integer_boot_image_offset = CalculateBootImageOffset(integer_class);
     if (invoke->InputAt(0)->IsIntConstant()) {
       int32_t input_value = invoke->InputAt(0)->AsIntConstant()->GetValue();
       uint32_t index = static_cast<uint32_t>(input_value) - static_cast<uint32_t>(info.low);
       if (index < static_cast<uint32_t>(info.length)) {
         ObjPtr<mirror::Object> integer =
             IntrinsicObjects::GetIntegerValueOfObject(boot_image_live_objects, index);
         info.value_boot_image_reference = CalculateBootImageOffset(integer);
       } else {
         // Not in the cache.
         info.value_boot_image_reference = IntegerValueOfInfo::kInvalidReference;
       }
     } else {
       info.array_data_boot_image_reference =
           CalculateBootImageOffset(boot_image_live_objects) +
           IntrinsicObjects::GetIntegerValueOfArrayDataOffset(boot_image_live_objects).Uint32Value();
     }
   }

   return info;
 }

 void IntrinsicVisitor::AssertNonMovableStringClass() {
   if (kIsDebugBuild) {
     ScopedObjectAccess soa(Thread::Current());
     ObjPtr<mirror::Class> string_class = GetClassRoot<art::mirror::String>();
     CHECK(!art::Runtime::Current()->GetHeap()->IsMovableObject(string_class));
   }
 }

 }  // namespace art
	/*
	* Copyright (C) 2015 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 "intrinsics.h"

	#include "art_field-inl.h"
	#include "art_method-inl.h"
	#include "base/utils.h"
	#include "class_linker.h"
	#include "class_root.h"
	#include "dex/invoke_type.h"
	#include "driver/compiler_options.h"
	#include "gc/space/image_space.h"
	#include "image-inl.h"
	#include "intrinsic_objects.h"
	#include "nodes.h"
	#include "obj_ptr-inl.h"
	#include "scoped_thread_state_change-inl.h"
	#include "thread-current-inl.h"

	namespace art {

	std::ostream& operator<<(std::ostream& os, const Intrinsics& intrinsic) {
	switch (intrinsic) {
	case Intrinsics::kNone:
	os << "None";
	break;
	#define OPTIMIZING_INTRINSICS(Name, IsStatic, NeedsEnvironmentOrCache, SideEffects, Exceptions, ...) \
	case Intrinsics::k ## Name: \
	os << # Name; \
	break;
	#include "intrinsics_list.h"
	INTRINSICS_LIST(OPTIMIZING_INTRINSICS)
	#undef STATIC_INTRINSICS_LIST
	#undef VIRTUAL_INTRINSICS_LIST
	#undef OPTIMIZING_INTRINSICS
	}
	return os;
	}

	static const char kIntegerCacheDescriptor[] = "Ljava/lang/Integer$IntegerCache;";
	static const char kIntegerDescriptor[] = "Ljava/lang/Integer;";
	static const char kIntegerArrayDescriptor[] = "[Ljava/lang/Integer;";
	static const char kLowFieldName[] = "low";
	static const char kHighFieldName[] = "high";
	static const char kValueFieldName[] = "value";

	static ObjPtr<mirror::ObjectArray<mirror::Object>> GetBootImageLiveObjects()
	REQUIRES_SHARED(Locks::mutator_lock_) {
	gc::Heap* heap = Runtime::Current()->GetHeap();
	const std::vector<gc::space::ImageSpace*>& boot_image_spaces = heap->GetBootImageSpaces();
	DCHECK(!boot_image_spaces.empty());
	const ImageHeader& main_header = boot_image_spaces[0]->GetImageHeader();
	ObjPtr<mirror::ObjectArray<mirror::Object>> boot_image_live_objects =
	ObjPtr<mirror::ObjectArray<mirror::Object>>::DownCast(
	main_header.GetImageRoot<kWithoutReadBarrier>(ImageHeader::kBootImageLiveObjects));
	DCHECK(boot_image_live_objects != nullptr);
	DCHECK(heap->ObjectIsInBootImageSpace(boot_image_live_objects));
	return boot_image_live_objects;
	}

	static ObjPtr<mirror::Class> LookupInitializedClass(Thread* self,
	ClassLinker* class_linker,
	const char* descriptor)
	REQUIRES_SHARED(Locks::mutator_lock_) {
	ObjPtr<mirror::Class> klass =
	class_linker->LookupClass(self, descriptor, /* class_loader= */ nullptr);
	DCHECK(klass != nullptr);
	DCHECK(klass->IsInitialized());
	return klass;
	}

	static ObjPtr<mirror::ObjectArray<mirror::Object>> GetIntegerCacheArray(
	ObjPtr<mirror::Class> cache_class) REQUIRES_SHARED(Locks::mutator_lock_) {
	ArtField* cache_field = cache_class->FindDeclaredStaticField("cache", kIntegerArrayDescriptor);
	DCHECK(cache_field != nullptr);
	return ObjPtr<mirror::ObjectArray<mirror::Object>>::DownCast(cache_field->GetObject(cache_class));
	}

	static int32_t GetIntegerCacheField(ObjPtr<mirror::Class> cache_class, const char* field_name)
	REQUIRES_SHARED(Locks::mutator_lock_) {
	ArtField* field = cache_class->FindDeclaredStaticField(field_name, "I");
	DCHECK(field != nullptr);
	return field->GetInt(cache_class);
	}

	static bool CheckIntegerCache(Thread* self,
	ClassLinker* class_linker,
	ObjPtr<mirror::ObjectArray<mirror::Object>> boot_image_live_objects,
	ObjPtr<mirror::ObjectArray<mirror::Object>> boot_image_cache)
	REQUIRES_SHARED(Locks::mutator_lock_) {
	DCHECK(boot_image_cache != nullptr);

	// Since we have a cache in the boot image, both java.lang.Integer and
	// java.lang.Integer$IntegerCache must be initialized in the boot image.
	ObjPtr<mirror::Class> cache_class =
	LookupInitializedClass(self, class_linker, kIntegerCacheDescriptor);
	ObjPtr<mirror::Class> integer_class =
	LookupInitializedClass(self, class_linker, kIntegerDescriptor);

	// Check that the current cache is the same as the `boot_image_cache`.
	ObjPtr<mirror::ObjectArray<mirror::Object>> current_cache = GetIntegerCacheArray(cache_class);
	if (current_cache != boot_image_cache) {
	return false; // Messed up IntegerCache.cache.
	}

	// Check that the range matches the boot image cache length.
	int32_t low = GetIntegerCacheField(cache_class, kLowFieldName);
	int32_t high = GetIntegerCacheField(cache_class, kHighFieldName);
	if (boot_image_cache->GetLength() != high - low + 1) {
	return false; // Messed up IntegerCache.low or IntegerCache.high.
	}

	// Check that the elements match the boot image intrinsic objects and check their values as well.
	ArtField* value_field = integer_class->FindDeclaredInstanceField(kValueFieldName, "I");
	DCHECK(value_field != nullptr);
	for (int32_t i = 0, len = boot_image_cache->GetLength(); i != len; ++i) {
	ObjPtr<mirror::Object> boot_image_object =
	IntrinsicObjects::GetIntegerValueOfObject(boot_image_live_objects, i);
	DCHECK(Runtime::Current()->GetHeap()->ObjectIsInBootImageSpace(boot_image_object));
	// No need for read barrier for comparison with a boot image object.
	ObjPtr<mirror::Object> current_object =
	boot_image_cache->GetWithoutChecks<kVerifyNone, kWithoutReadBarrier>(i);
	if (boot_image_object != current_object) {
	return false; // Messed up IntegerCache.cache[i]
	}
	if (value_field->GetInt(boot_image_object) != low + i) {
	return false; // Messed up IntegerCache.cache[i].value.
	}
	}

	return true;
	}

	void IntrinsicVisitor::ComputeIntegerValueOfLocations(HInvoke* invoke,
	CodeGenerator* codegen,
	Location return_location,
	Location first_argument_location) {
	// The intrinsic will call if it needs to allocate a j.l.Integer.
	LocationSummary::CallKind call_kind = LocationSummary::kCallOnMainOnly;
	const CompilerOptions& compiler_options = codegen->GetCompilerOptions();
	if (compiler_options.IsBootImage()) {
	// Piggyback on the method load kind to determine whether we can use PC-relative addressing.
	// This should cover both the testing config (non-PIC boot image) and codegens that reject
	// PC-relative load kinds and fall back to the runtime call.
	if (!invoke->AsInvokeStaticOrDirect()->HasPcRelativeMethodLoadKind()) {
	return;
	}
	if (!compiler_options.IsImageClass(kIntegerCacheDescriptor) \|\|
	!compiler_options.IsImageClass(kIntegerDescriptor)) {
	return;
	}
	ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
	Thread* self = Thread::Current();
	ScopedObjectAccess soa(self);
	ObjPtr<mirror::Class> cache_class = class_linker->LookupClass(
	self, kIntegerCacheDescriptor, /* class_loader= */ nullptr);
	DCHECK(cache_class != nullptr);
	if (UNLIKELY(!cache_class->IsInitialized())) {
	LOG(WARNING) << "Image class " << cache_class->PrettyDescriptor() << " is uninitialized.";
	return;
	}
	ObjPtr<mirror::Class> integer_class =
	class_linker->LookupClass(self, kIntegerDescriptor, /* class_loader= */ nullptr);
	DCHECK(integer_class != nullptr);
	if (UNLIKELY(!integer_class->IsInitialized())) {
	LOG(WARNING) << "Image class " << integer_class->PrettyDescriptor() << " is uninitialized.";
	return;
	}
	int32_t low = GetIntegerCacheField(cache_class, kLowFieldName);
	int32_t high = GetIntegerCacheField(cache_class, kHighFieldName);
	if (kIsDebugBuild) {
	ObjPtr<mirror::ObjectArray<mirror::Object>> current_cache = GetIntegerCacheArray(cache_class);
	CHECK(current_cache != nullptr);
	CHECK_EQ(current_cache->GetLength(), high - low + 1);
	ArtField* value_field = integer_class->FindDeclaredInstanceField(kValueFieldName, "I");
	CHECK(value_field != nullptr);
	for (int32_t i = 0, len = current_cache->GetLength(); i != len; ++i) {
	ObjPtr<mirror::Object> current_object = current_cache->GetWithoutChecks(i);
	CHECK(current_object != nullptr);
	CHECK_EQ(value_field->GetInt(current_object), low + i);
	}
	}
	if (invoke->InputAt(0)->IsIntConstant()) {
	int32_t value = invoke->InputAt(0)->AsIntConstant()->GetValue();
	if (static_cast<uint32_t>(value) - static_cast<uint32_t>(low) <
	static_cast<uint32_t>(high - low + 1)) {
	// No call, we shall use direct pointer to the Integer object.
	call_kind = LocationSummary::kNoCall;
	}
	}
	} else {
	Runtime* runtime = Runtime::Current();
	if (runtime->GetHeap()->GetBootImageSpaces().empty()) {
	return; // Running without boot image, cannot use required boot image objects.
	}
	Thread* self = Thread::Current();
	ScopedObjectAccess soa(self);
	ObjPtr<mirror::ObjectArray<mirror::Object>> boot_image_live_objects = GetBootImageLiveObjects();
	ObjPtr<mirror::ObjectArray<mirror::Object>> cache =
	IntrinsicObjects::GetIntegerValueOfCache(boot_image_live_objects);
	if (cache == nullptr) {
	return; // No cache in the boot image.
	}
	if (runtime->UseJitCompilation()) {
	if (!CheckIntegerCache(self, runtime->GetClassLinker(), boot_image_live_objects, cache)) {
	return; // The cache was somehow messed up, probably by using reflection.
	}
	} else {
	DCHECK(runtime->IsAotCompiler());
	DCHECK(CheckIntegerCache(self, runtime->GetClassLinker(), boot_image_live_objects, cache));
	if (invoke->InputAt(0)->IsIntConstant()) {
	int32_t value = invoke->InputAt(0)->AsIntConstant()->GetValue();
	// Retrieve the `value` from the lowest cached Integer.
	ObjPtr<mirror::Object> low_integer =
	IntrinsicObjects::GetIntegerValueOfObject(boot_image_live_objects, 0u);
	ObjPtr<mirror::Class> integer_class =
	low_integer->GetClass<kVerifyNone, kWithoutReadBarrier>();
	ArtField* value_field = integer_class->FindDeclaredInstanceField(kValueFieldName, "I");
	DCHECK(value_field != nullptr);
	int32_t low = value_field->GetInt(low_integer);
	if (static_cast<uint32_t>(value) - static_cast<uint32_t>(low) <
	static_cast<uint32_t>(cache->GetLength())) {
	// No call, we shall use direct pointer to the Integer object. Note that we cannot
	// do this for JIT as the "low" can change through reflection before emitting the code.
	call_kind = LocationSummary::kNoCall;
	}
	}
	}
	}

	ArenaAllocator* allocator = invoke->GetBlock()->GetGraph()->GetAllocator();
	LocationSummary* locations = new (allocator) LocationSummary(invoke, call_kind, kIntrinsified);
	if (call_kind == LocationSummary::kCallOnMainOnly) {
	locations->SetInAt(0, Location::RegisterOrConstant(invoke->InputAt(0)));
	locations->AddTemp(first_argument_location);
	locations->SetOut(return_location);
	} else {
	locations->SetInAt(0, Location::ConstantLocation(invoke->InputAt(0)->AsConstant()));
	locations->SetOut(Location::RequiresRegister());
	}
	}

	static int32_t GetIntegerCacheLowFromIntegerCache(Thread* self, ClassLinker* class_linker)
	REQUIRES_SHARED(Locks::mutator_lock_) {
	ObjPtr<mirror::Class> cache_class =
	LookupInitializedClass(self, class_linker, kIntegerCacheDescriptor);
	return GetIntegerCacheField(cache_class, kLowFieldName);
	}

	static uint32_t CalculateBootImageOffset(ObjPtr<mirror::Object> object)
	REQUIRES_SHARED(Locks::mutator_lock_) {
	gc::Heap* heap = Runtime::Current()->GetHeap();
	DCHECK(heap->ObjectIsInBootImageSpace(object));
	return reinterpret_cast<const uint8_t*>(object.Ptr()) - heap->GetBootImageSpaces()[0]->Begin();
	}

	inline IntrinsicVisitor::IntegerValueOfInfo::IntegerValueOfInfo()
	: value_offset(0),
	low(0),
	length(0u),
	integer_boot_image_offset(kInvalidReference),
	value_boot_image_reference(kInvalidReference) {}

	IntrinsicVisitor::IntegerValueOfInfo IntrinsicVisitor::ComputeIntegerValueOfInfo(
	HInvoke* invoke, const CompilerOptions& compiler_options) {
	// Note that we could cache all of the data looked up here. but there's no good
	// location for it. We don't want to add it to WellKnownClasses, to avoid creating global
	// jni values. Adding it as state to the compiler singleton seems like wrong
	// separation of concerns.
	// The need for this data should be pretty rare though.

	// Note that at this point we can no longer abort the code generation. Therefore,
	// we need to provide data that shall not lead to a crash even if the fields were
	// modified through reflection since ComputeIntegerValueOfLocations() when JITting.

	Runtime* runtime = Runtime::Current();
	ClassLinker* class_linker = runtime->GetClassLinker();
	Thread* self = Thread::Current();
	ScopedObjectAccess soa(self);

	IntegerValueOfInfo info;
	if (compiler_options.IsBootImage()) {
	ObjPtr<mirror::Class> integer_class =
	LookupInitializedClass(self, class_linker, kIntegerDescriptor);
	ArtField* value_field = integer_class->FindDeclaredInstanceField(kValueFieldName, "I");
	DCHECK(value_field != nullptr);
	info.value_offset = value_field->GetOffset().Uint32Value();
	ObjPtr<mirror::Class> cache_class =
	LookupInitializedClass(self, class_linker, kIntegerCacheDescriptor);
	info.low = GetIntegerCacheField(cache_class, kLowFieldName);
	int32_t high = GetIntegerCacheField(cache_class, kHighFieldName);
	info.length = dchecked_integral_cast<uint32_t>(high - info.low + 1);

	info.integer_boot_image_offset = IntegerValueOfInfo::kInvalidReference;
	if (invoke->InputAt(0)->IsIntConstant()) {
	int32_t input_value = invoke->InputAt(0)->AsIntConstant()->GetValue();
	uint32_t index = static_cast<uint32_t>(input_value) - static_cast<uint32_t>(info.low);
	if (index < static_cast<uint32_t>(info.length)) {
	info.value_boot_image_reference = IntrinsicObjects::EncodePatch(
	IntrinsicObjects::PatchType::kIntegerValueOfObject, index);
	} else {
	// Not in the cache.
	info.value_boot_image_reference = IntegerValueOfInfo::kInvalidReference;
	}
	} else {
	info.array_data_boot_image_reference =
	IntrinsicObjects::EncodePatch(IntrinsicObjects::PatchType::kIntegerValueOfArray);
	}
	} else {
	ObjPtr<mirror::ObjectArray<mirror::Object>> boot_image_live_objects = GetBootImageLiveObjects();
	ObjPtr<mirror::Object> low_integer =
	IntrinsicObjects::GetIntegerValueOfObject(boot_image_live_objects, 0u);
	ObjPtr<mirror::Class> integer_class = low_integer->GetClass<kVerifyNone, kWithoutReadBarrier>();
	ArtField* value_field = integer_class->FindDeclaredInstanceField(kValueFieldName, "I");
	DCHECK(value_field != nullptr);
	info.value_offset = value_field->GetOffset().Uint32Value();
	if (runtime->UseJitCompilation()) {
	// Use the current `IntegerCache.low` for JIT to avoid truly surprising behavior if the
	// code messes up the `value` field in the lowest cached Integer using reflection.
	info.low = GetIntegerCacheLowFromIntegerCache(self, class_linker);
	} else {
	// For app AOT, the `low_integer->value` should be the same as `IntegerCache.low`.
	info.low = value_field->GetInt(low_integer);
	DCHECK_EQ(info.low, GetIntegerCacheLowFromIntegerCache(self, class_linker));
	}
	// Do not look at `IntegerCache.high`, use the immutable length of the cache array instead.
	info.length = dchecked_integral_cast<uint32_t>(
	IntrinsicObjects::GetIntegerValueOfCache(boot_image_live_objects)->GetLength());

	info.integer_boot_image_offset = CalculateBootImageOffset(integer_class);
	if (invoke->InputAt(0)->IsIntConstant()) {
	int32_t input_value = invoke->InputAt(0)->AsIntConstant()->GetValue();
	uint32_t index = static_cast<uint32_t>(input_value) - static_cast<uint32_t>(info.low);
	if (index < static_cast<uint32_t>(info.length)) {
	ObjPtr<mirror::Object> integer =
	IntrinsicObjects::GetIntegerValueOfObject(boot_image_live_objects, index);
	info.value_boot_image_reference = CalculateBootImageOffset(integer);
	} else {
	// Not in the cache.
	info.value_boot_image_reference = IntegerValueOfInfo::kInvalidReference;
	}
	} else {
	info.array_data_boot_image_reference =
	CalculateBootImageOffset(boot_image_live_objects) +
	IntrinsicObjects::GetIntegerValueOfArrayDataOffset(boot_image_live_objects).Uint32Value();
	}
	}

	return info;
	}

	void IntrinsicVisitor::AssertNonMovableStringClass() {
	if (kIsDebugBuild) {
	ScopedObjectAccess soa(Thread::Current());
	ObjPtr<mirror::Class> string_class = GetClassRoot<art::mirror::String>();
	CHECK(!art::Runtime::Current()->GetHeap()->IsMovableObject(string_class));
	}
	}

	} // namespace art