compiler/optimizing/intrinsics_utils.h - platform/art - Git at Google

 /*
  * 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.
  */

 #ifndef ART_COMPILER_OPTIMIZING_INTRINSICS_UTILS_H_
 #define ART_COMPILER_OPTIMIZING_INTRINSICS_UTILS_H_

 #include "base/casts.h"
 #include "base/macros.h"
 #include "class_root-inl.h"
 #include "code_generator.h"
 #include "data_type-inl.h"
 #include "dex/dex_file-inl.h"
 #include "locations.h"
 #include "mirror/var_handle.h"
 #include "nodes.h"
 #include "utils/assembler.h"
 #include "utils/label.h"

 namespace art {

 // Default slow-path for fallback (calling the managed code to handle the intrinsic) in an
 // intrinsified call. This will copy the arguments into the positions for a regular call.
 //
 // Note: The actual parameters are required to be in the locations given by the invoke's location
 //       summary. If an intrinsic modifies those locations before a slowpath call, they must be
 //       restored!
 //
 // Note: If an invoke wasn't sharpened, we will put down an invoke-virtual here. That's potentially
 //       sub-optimal (compared to a direct pointer call), but this is a slow-path.

 template <typename TDexCallingConvention,
           typename TSlowPathCode = SlowPathCode,
           typename TAssembler = Assembler>
 class IntrinsicSlowPath : public TSlowPathCode {
  public:
   explicit IntrinsicSlowPath(HInvoke* invoke) : TSlowPathCode(invoke), invoke_(invoke) { }

   Location MoveArguments(CodeGenerator* codegen) {
     TDexCallingConvention calling_convention_visitor;
     IntrinsicVisitor::MoveArguments(invoke_, codegen, &calling_convention_visitor);
     return calling_convention_visitor.GetMethodLocation();
   }

   void EmitNativeCode(CodeGenerator* codegen) override {
     TAssembler* assembler = down_cast<TAssembler*>(codegen->GetAssembler());
     assembler->Bind(this->GetEntryLabel());

     this->SaveLiveRegisters(codegen, invoke_->GetLocations());

     Location method_loc = MoveArguments(codegen);

     if (invoke_->IsInvokeStaticOrDirect()) {
       HInvokeStaticOrDirect* invoke_static_or_direct = invoke_->AsInvokeStaticOrDirect();
       DCHECK_NE(invoke_static_or_direct->GetMethodLoadKind(), MethodLoadKind::kRecursive);
       DCHECK_NE(invoke_static_or_direct->GetCodePtrLocation(),
                 CodePtrLocation::kCallCriticalNative);
       codegen->GenerateStaticOrDirectCall(invoke_static_or_direct, method_loc, this);
     } else if (invoke_->IsInvokeVirtual()) {
       codegen->GenerateVirtualCall(invoke_->AsInvokeVirtual(), method_loc, this);
     } else {
       DCHECK(invoke_->IsInvokePolymorphic());
       codegen->GenerateInvokePolymorphicCall(invoke_->AsInvokePolymorphic(), this);
     }

     // Copy the result back to the expected output.
     Location out = invoke_->GetLocations()->Out();
     if (out.IsValid()) {
       DCHECK(out.IsRegisterKind());  // TODO: Replace this when we support output in memory.
       // We want to double-check that we don't overwrite a live register with the return
       // value.
       // Note: For the possible kNoOutputOverlap case we can't simply remove the OUT register
       // from the GetLiveRegisters() - theoretically it might be needed after the return from
       // the slow path.
       DCHECK(!invoke_->GetLocations()->GetLiveRegisters()->OverlapsRegisters(out));
       codegen->MoveFromReturnRegister(out, invoke_->GetType());
     }

     this->RestoreLiveRegisters(codegen, invoke_->GetLocations());
     assembler->Jump(this->GetExitLabel());
   }

   const char* GetDescription() const override { return "IntrinsicSlowPath"; }

  private:
   // The instruction where this slow path is happening.
   HInvoke* const invoke_;

   DISALLOW_COPY_AND_ASSIGN(IntrinsicSlowPath);
 };

 static inline size_t GetExpectedVarHandleCoordinatesCount(HInvoke *invoke) {
   mirror::VarHandle::AccessModeTemplate access_mode_template =
       mirror::VarHandle::GetAccessModeTemplateByIntrinsic(invoke->GetIntrinsic());
   size_t var_type_count = mirror::VarHandle::GetNumberOfVarTypeParameters(access_mode_template);
   size_t accessor_argument_count = invoke->GetNumberOfArguments() - 1;

   return accessor_argument_count - var_type_count;
 }

 static inline DataType::Type GetDataTypeFromShorty(HInvoke* invoke, uint32_t index) {
   DCHECK(invoke->IsInvokePolymorphic());
   const DexFile* dex_file = invoke->GetMethodReference().dex_file;
   const char* shorty = dex_file->GetShorty(invoke->AsInvokePolymorphic()->GetProtoIndex());
   DCHECK_LT(index, strlen(shorty));

   return DataType::FromShorty(shorty[index]);
 }

 static inline bool IsVarHandleGetAndBitwiseOp(HInvoke* invoke) {
   switch (invoke->GetIntrinsic()) {
     case Intrinsics::kVarHandleGetAndBitwiseOr:
     case Intrinsics::kVarHandleGetAndBitwiseOrAcquire:
     case Intrinsics::kVarHandleGetAndBitwiseOrRelease:
     case Intrinsics::kVarHandleGetAndBitwiseXor:
     case Intrinsics::kVarHandleGetAndBitwiseXorAcquire:
     case Intrinsics::kVarHandleGetAndBitwiseXorRelease:
     case Intrinsics::kVarHandleGetAndBitwiseAnd:
     case Intrinsics::kVarHandleGetAndBitwiseAndAcquire:
     case Intrinsics::kVarHandleGetAndBitwiseAndRelease:
       return true;
     default:
       return false;
   }
 }

 static inline bool IsVarHandleGetAndAdd(HInvoke* invoke) {
   switch (invoke->GetIntrinsic()) {
     case Intrinsics::kVarHandleGetAndAdd:
     case Intrinsics::kVarHandleGetAndAddAcquire:
     case Intrinsics::kVarHandleGetAndAddRelease:
       return true;
     default:
       return false;
   }
 }

 static inline bool IsVarHandleGet(HInvoke* invoke) {
   mirror::VarHandle::AccessModeTemplate access_mode =
       mirror::VarHandle::GetAccessModeTemplateByIntrinsic(invoke->GetIntrinsic());
   return access_mode == mirror::VarHandle::AccessModeTemplate::kGet;
 }

 static inline bool IsUnsafeGetObject(HInvoke* invoke) {
   switch (invoke->GetIntrinsic()) {
     case Intrinsics::kUnsafeGetObject:
     case Intrinsics::kUnsafeGetObjectVolatile:
     case Intrinsics::kJdkUnsafeGetObject:
     case Intrinsics::kJdkUnsafeGetObjectVolatile:
     case Intrinsics::kJdkUnsafeGetObjectAcquire:
       return true;
     default:
       return false;
   }
 }

 static inline bool IsUnsafeCASObject(HInvoke* invoke) {
   switch (invoke->GetIntrinsic()) {
     case Intrinsics::kUnsafeCASObject:
     case Intrinsics::kJdkUnsafeCASObject:
     case Intrinsics::kJdkUnsafeCompareAndSetObject:
       return true;
     default:
       return false;
   }
 }

 static inline bool IsVarHandleCASFamily(HInvoke* invoke) {
   mirror::VarHandle::AccessModeTemplate access_mode =
       mirror::VarHandle::GetAccessModeTemplateByIntrinsic(invoke->GetIntrinsic());
   return access_mode == mirror::VarHandle::AccessModeTemplate::kCompareAndSet ||
       access_mode == mirror::VarHandle::AccessModeTemplate::kGetAndUpdate ||
       access_mode == mirror::VarHandle::AccessModeTemplate::kCompareAndExchange;
 }

 static inline DataType::Type GetVarHandleExpectedValueType(HInvoke* invoke,
                                                            size_t expected_coordinates_count) {
   DCHECK_EQ(expected_coordinates_count, GetExpectedVarHandleCoordinatesCount(invoke));
   uint32_t number_of_arguments = invoke->GetNumberOfArguments();
   DCHECK_GE(number_of_arguments, /* VarHandle object */ 1u + expected_coordinates_count);
   if (number_of_arguments == /* VarHandle object */ 1u + expected_coordinates_count) {
     return invoke->GetType();
   } else {
     return GetDataTypeFromShorty(invoke, number_of_arguments - 1u);
   }
 }

 static inline ArtField* GetBootImageVarHandleField(HInvoke* invoke)
     REQUIRES_SHARED(Locks::mutator_lock_) {
   DCHECK_LE(GetExpectedVarHandleCoordinatesCount(invoke), 1u);
   DCHECK(VarHandleOptimizations(invoke).GetUseKnownBootImageVarHandle());
   HInstruction* var_handle_instruction = invoke->InputAt(0);
   if (var_handle_instruction->IsNullCheck()) {
     var_handle_instruction = var_handle_instruction->InputAt(0);
   }
   DCHECK(var_handle_instruction->IsStaticFieldGet());
   ArtField* field = var_handle_instruction->AsStaticFieldGet()->GetFieldInfo().GetField();
   DCHECK(field->IsStatic());
   DCHECK(field->IsFinal());
   DCHECK(var_handle_instruction->InputAt(0)->AsLoadClass()->IsInBootImage());
   ObjPtr<mirror::Object> var_handle = field->GetObject(field->GetDeclaringClass());
   DCHECK(var_handle->GetClass() ==
          (GetExpectedVarHandleCoordinatesCount(invoke) == 0u
              ? GetClassRoot<mirror::StaticFieldVarHandle>()
              : GetClassRoot<mirror::FieldVarHandle>()));
   static_assert(std::is_base_of_v<mirror::FieldVarHandle, mirror::StaticFieldVarHandle>);
   return ObjPtr<mirror::FieldVarHandle>::DownCast(var_handle)->GetArtField();
 }

 }  // namespace art

 #endif  // ART_COMPILER_OPTIMIZING_INTRINSICS_UTILS_H_
	/*
	* 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.
	*/

	#ifndef ART_COMPILER_OPTIMIZING_INTRINSICS_UTILS_H_
	#define ART_COMPILER_OPTIMIZING_INTRINSICS_UTILS_H_

	#include "base/casts.h"
	#include "base/macros.h"
	#include "class_root-inl.h"
	#include "code_generator.h"
	#include "data_type-inl.h"
	#include "dex/dex_file-inl.h"
	#include "locations.h"
	#include "mirror/var_handle.h"
	#include "nodes.h"
	#include "utils/assembler.h"
	#include "utils/label.h"

	namespace art {

	// Default slow-path for fallback (calling the managed code to handle the intrinsic) in an
	// intrinsified call. This will copy the arguments into the positions for a regular call.
	//
	// Note: The actual parameters are required to be in the locations given by the invoke's location
	// summary. If an intrinsic modifies those locations before a slowpath call, they must be
	// restored!
	//
	// Note: If an invoke wasn't sharpened, we will put down an invoke-virtual here. That's potentially
	// sub-optimal (compared to a direct pointer call), but this is a slow-path.

	template <typename TDexCallingConvention,
	typename TSlowPathCode = SlowPathCode,
	typename TAssembler = Assembler>
	class IntrinsicSlowPath : public TSlowPathCode {
	public:
	explicit IntrinsicSlowPath(HInvoke* invoke) : TSlowPathCode(invoke), invoke_(invoke) { }

	Location MoveArguments(CodeGenerator* codegen) {
	TDexCallingConvention calling_convention_visitor;
	IntrinsicVisitor::MoveArguments(invoke_, codegen, &calling_convention_visitor);
	return calling_convention_visitor.GetMethodLocation();
	}

	void EmitNativeCode(CodeGenerator* codegen) override {
	TAssembler* assembler = down_cast<TAssembler*>(codegen->GetAssembler());
	assembler->Bind(this->GetEntryLabel());

	this->SaveLiveRegisters(codegen, invoke_->GetLocations());

	Location method_loc = MoveArguments(codegen);

	if (invoke_->IsInvokeStaticOrDirect()) {
	HInvokeStaticOrDirect* invoke_static_or_direct = invoke_->AsInvokeStaticOrDirect();
	DCHECK_NE(invoke_static_or_direct->GetMethodLoadKind(), MethodLoadKind::kRecursive);
	DCHECK_NE(invoke_static_or_direct->GetCodePtrLocation(),
	CodePtrLocation::kCallCriticalNative);
	codegen->GenerateStaticOrDirectCall(invoke_static_or_direct, method_loc, this);
	} else if (invoke_->IsInvokeVirtual()) {
	codegen->GenerateVirtualCall(invoke_->AsInvokeVirtual(), method_loc, this);
	} else {
	DCHECK(invoke_->IsInvokePolymorphic());
	codegen->GenerateInvokePolymorphicCall(invoke_->AsInvokePolymorphic(), this);
	}

	// Copy the result back to the expected output.
	Location out = invoke_->GetLocations()->Out();
	if (out.IsValid()) {
	DCHECK(out.IsRegisterKind()); // TODO: Replace this when we support output in memory.
	// We want to double-check that we don't overwrite a live register with the return
	// value.
	// Note: For the possible kNoOutputOverlap case we can't simply remove the OUT register
	// from the GetLiveRegisters() - theoretically it might be needed after the return from
	// the slow path.
	DCHECK(!invoke_->GetLocations()->GetLiveRegisters()->OverlapsRegisters(out));
	codegen->MoveFromReturnRegister(out, invoke_->GetType());
	}

	this->RestoreLiveRegisters(codegen, invoke_->GetLocations());
	assembler->Jump(this->GetExitLabel());
	}

	const char* GetDescription() const override { return "IntrinsicSlowPath"; }

	private:
	// The instruction where this slow path is happening.
	HInvoke* const invoke_;

	DISALLOW_COPY_AND_ASSIGN(IntrinsicSlowPath);
	};

	static inline size_t GetExpectedVarHandleCoordinatesCount(HInvoke *invoke) {
	mirror::VarHandle::AccessModeTemplate access_mode_template =
	mirror::VarHandle::GetAccessModeTemplateByIntrinsic(invoke->GetIntrinsic());
	size_t var_type_count = mirror::VarHandle::GetNumberOfVarTypeParameters(access_mode_template);
	size_t accessor_argument_count = invoke->GetNumberOfArguments() - 1;

	return accessor_argument_count - var_type_count;
	}

	static inline DataType::Type GetDataTypeFromShorty(HInvoke* invoke, uint32_t index) {
	DCHECK(invoke->IsInvokePolymorphic());
	const DexFile* dex_file = invoke->GetMethodReference().dex_file;
	const char* shorty = dex_file->GetShorty(invoke->AsInvokePolymorphic()->GetProtoIndex());
	DCHECK_LT(index, strlen(shorty));

	return DataType::FromShorty(shorty[index]);
	}

	static inline bool IsVarHandleGetAndBitwiseOp(HInvoke* invoke) {
	switch (invoke->GetIntrinsic()) {
	case Intrinsics::kVarHandleGetAndBitwiseOr:
	case Intrinsics::kVarHandleGetAndBitwiseOrAcquire:
	case Intrinsics::kVarHandleGetAndBitwiseOrRelease:
	case Intrinsics::kVarHandleGetAndBitwiseXor:
	case Intrinsics::kVarHandleGetAndBitwiseXorAcquire:
	case Intrinsics::kVarHandleGetAndBitwiseXorRelease:
	case Intrinsics::kVarHandleGetAndBitwiseAnd:
	case Intrinsics::kVarHandleGetAndBitwiseAndAcquire:
	case Intrinsics::kVarHandleGetAndBitwiseAndRelease:
	return true;
	default:
	return false;
	}
	}

	static inline bool IsVarHandleGetAndAdd(HInvoke* invoke) {
	switch (invoke->GetIntrinsic()) {
	case Intrinsics::kVarHandleGetAndAdd:
	case Intrinsics::kVarHandleGetAndAddAcquire:
	case Intrinsics::kVarHandleGetAndAddRelease:
	return true;
	default:
	return false;
	}
	}

	static inline bool IsVarHandleGet(HInvoke* invoke) {
	mirror::VarHandle::AccessModeTemplate access_mode =
	mirror::VarHandle::GetAccessModeTemplateByIntrinsic(invoke->GetIntrinsic());
	return access_mode == mirror::VarHandle::AccessModeTemplate::kGet;
	}

	static inline bool IsUnsafeGetObject(HInvoke* invoke) {
	switch (invoke->GetIntrinsic()) {
	case Intrinsics::kUnsafeGetObject:
	case Intrinsics::kUnsafeGetObjectVolatile:
	case Intrinsics::kJdkUnsafeGetObject:
	case Intrinsics::kJdkUnsafeGetObjectVolatile:
	case Intrinsics::kJdkUnsafeGetObjectAcquire:
	return true;
	default:
	return false;
	}
	}

	static inline bool IsUnsafeCASObject(HInvoke* invoke) {
	switch (invoke->GetIntrinsic()) {
	case Intrinsics::kUnsafeCASObject:
	case Intrinsics::kJdkUnsafeCASObject:
	case Intrinsics::kJdkUnsafeCompareAndSetObject:
	return true;
	default:
	return false;
	}
	}

	static inline bool IsVarHandleCASFamily(HInvoke* invoke) {
	mirror::VarHandle::AccessModeTemplate access_mode =
	mirror::VarHandle::GetAccessModeTemplateByIntrinsic(invoke->GetIntrinsic());
	return access_mode == mirror::VarHandle::AccessModeTemplate::kCompareAndSet \|\|
	access_mode == mirror::VarHandle::AccessModeTemplate::kGetAndUpdate \|\|
	access_mode == mirror::VarHandle::AccessModeTemplate::kCompareAndExchange;
	}

	static inline DataType::Type GetVarHandleExpectedValueType(HInvoke* invoke,
	size_t expected_coordinates_count) {
	DCHECK_EQ(expected_coordinates_count, GetExpectedVarHandleCoordinatesCount(invoke));
	uint32_t number_of_arguments = invoke->GetNumberOfArguments();
	DCHECK_GE(number_of_arguments, /* VarHandle object */ 1u + expected_coordinates_count);
	if (number_of_arguments == /* VarHandle object */ 1u + expected_coordinates_count) {
	return invoke->GetType();
	} else {
	return GetDataTypeFromShorty(invoke, number_of_arguments - 1u);
	}
	}

	static inline ArtField* GetBootImageVarHandleField(HInvoke* invoke)
	REQUIRES_SHARED(Locks::mutator_lock_) {
	DCHECK_LE(GetExpectedVarHandleCoordinatesCount(invoke), 1u);
	DCHECK(VarHandleOptimizations(invoke).GetUseKnownBootImageVarHandle());
	HInstruction* var_handle_instruction = invoke->InputAt(0);
	if (var_handle_instruction->IsNullCheck()) {
	var_handle_instruction = var_handle_instruction->InputAt(0);
	}
	DCHECK(var_handle_instruction->IsStaticFieldGet());
	ArtField* field = var_handle_instruction->AsStaticFieldGet()->GetFieldInfo().GetField();
	DCHECK(field->IsStatic());
	DCHECK(field->IsFinal());
	DCHECK(var_handle_instruction->InputAt(0)->AsLoadClass()->IsInBootImage());
	ObjPtr<mirror::Object> var_handle = field->GetObject(field->GetDeclaringClass());
	DCHECK(var_handle->GetClass() ==
	(GetExpectedVarHandleCoordinatesCount(invoke) == 0u
	? GetClassRoot<mirror::StaticFieldVarHandle>()
	: GetClassRoot<mirror::FieldVarHandle>()));
	static_assert(std::is_base_of_v<mirror::FieldVarHandle, mirror::StaticFieldVarHandle>);
	return ObjPtr<mirror::FieldVarHandle>::DownCast(var_handle)->GetArtField();
	}

	} // namespace art

	#endif // ART_COMPILER_OPTIMIZING_INTRINSICS_UTILS_H_