src/calling_convention.h - platform/art - Gitiles

 /*
  * 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.
  */

 #ifndef ART_SRC_CALLING_CONVENTION_H_
 #define ART_SRC_CALLING_CONVENTION_H_

 #include <vector>
 #include "managed_register.h"
 #include "stack_indirect_reference_table.h"
 #include "thread.h"

 namespace art {

 // Top-level abstraction for different calling conventions
 class CallingConvention {
  public:
   bool IsReturnAReference() const { return shorty_[0] == 'L'; }

   size_t SizeOfReturnValue() const {
     size_t result = Primitive::ComponentSize(Primitive::GetType(shorty_[0]));
     if (result >= 1 && result < 4) {
       result = 4;
     }
     return result;
   }

   // Register that holds result of this method
   virtual ManagedRegister ReturnRegister() = 0;
   // Register reserved for scratch usage during procedure calls
   virtual ManagedRegister InterproceduralScratchRegister() = 0;

   // Offset of Method within the frame
   FrameOffset MethodStackOffset();

   // Iterator interface

   // Place iterator at start of arguments. The displacement is applied to
   // frame offset methods to account for frames which may be on the stack
   // below the one being iterated over.
   void ResetIterator(FrameOffset displacement) {
     displacement_ = displacement;
     itr_slots_ = 0;
     itr_args_ = 0;
     itr_refs_ = 0;
     itr_longs_and_doubles_ = 0;
   }

   virtual ~CallingConvention() {}

  protected:
   CallingConvention(bool is_static, bool is_synchronized, const char* shorty)
       : displacement_(0), is_static_(is_static), is_synchronized_(is_synchronized),
         shorty_(shorty) {
     num_args_ = (is_static ? 0 : 1) + strlen(shorty) - 1;
     num_ref_args_ = is_static ? 0 : 1;  // The implicit this pointer.
     num_long_or_double_args_ = 0;
     for (size_t i = 1; i < strlen(shorty); i++) {
       char ch = shorty_[i];
       if (ch == 'L') {
         num_ref_args_++;
       } else if ((ch == 'D') || (ch == 'J')) {
         num_long_or_double_args_++;
       }
     }
   }

   bool IsStatic() const {
     return is_static_;
   }
   bool IsSynchronized() const {
     return is_synchronized_;
   }
   bool IsParamALongOrDouble(unsigned int param) const {
     DCHECK_LT(param, NumArgs());
     if (IsStatic()) {
       param++;  // 0th argument must skip return value at start of the shorty
     } else if (param == 0) {
       return false;  // this argument
     }
     char ch = shorty_[param];
     return (ch == 'J' || ch == 'D');
   }
   bool IsParamAReference(unsigned int param) const {
     DCHECK_LT(param, NumArgs());
     if (IsStatic()) {
       param++;  // 0th argument must skip return value at start of the shorty
     } else if (param == 0) {
       return true;  // this argument
     }
     return shorty_[param] == 'L';
   }
   size_t NumArgs() const {
     return num_args_;
   }
   size_t NumLongOrDoubleArgs() const {
     return num_long_or_double_args_;
   }
   size_t NumReferenceArgs() const {
     return num_ref_args_;
   }
   size_t ParamSize(unsigned int param) const {
     DCHECK_LT(param, NumArgs());
     if (IsStatic()) {
       param++;  // 0th argument must skip return value at start of the shorty
     } else if (param == 0) {
       return kPointerSize;  // this argument
     }
     size_t result = Primitive::ComponentSize(Primitive::GetType(shorty_[param]));
     if (result >= 1 && result < 4) {
       result = 4;
     }
     return result;
   }
   const char* GetShorty() const {
     return shorty_.c_str();
   }
   // The slot number for current calling_convention argument.
   // Note that each slot is 32-bit. When the current argument is bigger
   // than 32 bits, return the first slot number for this argument.
   unsigned int itr_slots_;
   // The number of references iterated past
   unsigned int itr_refs_;
   // The argument number along argument list for current argument
   unsigned int itr_args_;
   // Number of longs and doubles seen along argument list
   unsigned int itr_longs_and_doubles_;
   // Space for frames below this on the stack
   FrameOffset displacement_;

  private:
   const bool is_static_;
   const bool is_synchronized_;
   std::string shorty_;
   size_t num_args_;
   size_t num_ref_args_;
   size_t num_long_or_double_args_;
 };

 // Abstraction for managed code's calling conventions
 // | { Incoming stack args } |
 // | { Prior Method* }       | <-- Prior SP
 // | { Return address }      |
 // | { Callee saves }        |
 // | { Spills ... }          |
 // | { Outgoing stack args } |
 // | { Method* }             | <-- SP
 class ManagedRuntimeCallingConvention : public CallingConvention {
  public:
   static ManagedRuntimeCallingConvention* Create(bool is_static, bool is_synchronized,
                                                  const char* shorty,
                                                  InstructionSet instruction_set);

   // Register that holds the incoming method argument
   virtual ManagedRegister MethodRegister() = 0;

   // Iterator interface
   bool HasNext();
   void Next();
   bool IsCurrentParamAReference();
   bool IsCurrentArgExplicit();  // ie a non-implict argument such as this
   bool IsCurrentArgPossiblyNull();
   size_t CurrentParamSize();
   virtual bool IsCurrentParamInRegister() = 0;
   virtual bool IsCurrentParamOnStack() = 0;
   virtual ManagedRegister CurrentParamRegister() = 0;
   virtual FrameOffset CurrentParamStackOffset() = 0;

   virtual ~ManagedRuntimeCallingConvention() {}

   // Registers to spill to caller's out registers on entry.
   virtual const std::vector<ManagedRegister>& EntrySpills() = 0;

  protected:
   ManagedRuntimeCallingConvention(bool is_static, bool is_synchronized, const char* shorty) :
       CallingConvention(is_static, is_synchronized, shorty) {}
 };

 // Abstraction for JNI calling conventions
 // | { Incoming stack args }         | <-- Prior SP
 // | { Return address }              |
 // | { Callee saves }                |     ([1])
 // | { Return value spill }          |     (live on return slow paths)
 // | { Local Ref. Table State }      |
 // | { Stack Indirect Ref. Table     |
 // |   num. refs./link }             |     (here to prior SP is frame size)
 // | { Method* }                     | <-- Anchor SP written to thread
 // | { Outgoing stack args }         | <-- SP at point of call
 // | Native frame                    |
 //
 // [1] We must save all callee saves here to enable any exception throws to restore
 // callee saves for frames above this one.
 class JniCallingConvention : public CallingConvention {
  public:
   static JniCallingConvention* Create(bool is_static, bool is_synchronized, const char* shorty,
                                       InstructionSet instruction_set);

   // Size of frame excluding space for outgoing args (its assumed Method* is
   // always at the bottom of a frame, but this doesn't work for outgoing
   // native args). Includes alignment.
   virtual size_t FrameSize() = 0;
   // Size of outgoing arguments, including alignment
   virtual size_t OutArgSize() = 0;
   // Number of references in stack indirect reference table
   size_t ReferenceCount() const;
   // Location where the segment state of the local indirect reference table is saved
   FrameOffset SavedLocalReferenceCookieOffset() const;
   // Location where the return value of a call can be squirreled if another
   // call is made following the native call
   FrameOffset ReturnValueSaveLocation() const;

   // Callee save registers to spill prior to native code (which may clobber)
   virtual const std::vector<ManagedRegister>& CalleeSaveRegisters() const = 0;

   // Spill mask values
   virtual uint32_t CoreSpillMask() const = 0;
   virtual uint32_t FpSpillMask() const = 0;

   // Returns true if the method register will have been clobbered during argument
   // set up
   virtual bool IsMethodRegisterClobberedPreCall() = 0;

   // An extra scratch register live after the call
   virtual ManagedRegister ReturnScratchRegister() const = 0;

   // Iterator interface
   bool HasNext();
   virtual void Next();
   bool IsCurrentParamAReference();
   size_t CurrentParamSize();
   virtual bool IsCurrentParamInRegister() = 0;
   virtual bool IsCurrentParamOnStack() = 0;
   virtual ManagedRegister CurrentParamRegister() = 0;
   virtual FrameOffset CurrentParamStackOffset() = 0;

   // Iterator interface extension for JNI
   FrameOffset CurrentParamSirtEntryOffset();

   // Position of SIRT and interior fields
   FrameOffset SirtOffset() const {
     return FrameOffset(displacement_.Int32Value() +
                        kPointerSize);  // above Method*
   }
   FrameOffset SirtNumRefsOffset() const {
     return FrameOffset(SirtOffset().Int32Value() +
                        StackIndirectReferenceTable::NumberOfReferencesOffset());
   }
   FrameOffset SirtLinkOffset() const {
     return FrameOffset(SirtOffset().Int32Value() +
                        StackIndirectReferenceTable::LinkOffset());
   }

   virtual ~JniCallingConvention() {}

  protected:
   // Named iterator positions
   enum IteratorPos {
     kJniEnv = 0,
     kObjectOrClass = 1
   };

   explicit JniCallingConvention(bool is_static, bool is_synchronized, const char* shorty) :
       CallingConvention(is_static, is_synchronized, shorty) {}

   // Number of stack slots for outgoing arguments, above which the SIRT is
   // located
   virtual size_t NumberOfOutgoingStackArgs() = 0;

  protected:
   size_t NumberOfExtraArgumentsForJni();
 };

 }  // namespace art

 #endif  // ART_SRC_CALLING_CONVENTION_H_
	/*
	* 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.
	*/

	#ifndef ART_SRC_CALLING_CONVENTION_H_
	#define ART_SRC_CALLING_CONVENTION_H_

	#include <vector>
	#include "managed_register.h"
	#include "stack_indirect_reference_table.h"
	#include "thread.h"

	namespace art {

	// Top-level abstraction for different calling conventions
	class CallingConvention {
	public:
	bool IsReturnAReference() const { return shorty_[0] == 'L'; }

	size_t SizeOfReturnValue() const {
	size_t result = Primitive::ComponentSize(Primitive::GetType(shorty_[0]));
	if (result >= 1 && result < 4) {
	result = 4;
	}
	return result;
	}

	// Register that holds result of this method
	virtual ManagedRegister ReturnRegister() = 0;
	// Register reserved for scratch usage during procedure calls
	virtual ManagedRegister InterproceduralScratchRegister() = 0;

	// Offset of Method within the frame
	FrameOffset MethodStackOffset();

	// Iterator interface

	// Place iterator at start of arguments. The displacement is applied to
	// frame offset methods to account for frames which may be on the stack
	// below the one being iterated over.
	void ResetIterator(FrameOffset displacement) {
	displacement_ = displacement;
	itr_slots_ = 0;
	itr_args_ = 0;
	itr_refs_ = 0;
	itr_longs_and_doubles_ = 0;
	}

	virtual ~CallingConvention() {}

	protected:
	CallingConvention(bool is_static, bool is_synchronized, const char* shorty)
	: displacement_(0), is_static_(is_static), is_synchronized_(is_synchronized),
	shorty_(shorty) {
	num_args_ = (is_static ? 0 : 1) + strlen(shorty) - 1;
	num_ref_args_ = is_static ? 0 : 1; // The implicit this pointer.
	num_long_or_double_args_ = 0;
	for (size_t i = 1; i < strlen(shorty); i++) {
	char ch = shorty_[i];
	if (ch == 'L') {
	num_ref_args_++;
	} else if ((ch == 'D') \|\| (ch == 'J')) {
	num_long_or_double_args_++;
	}
	}
	}

	bool IsStatic() const {
	return is_static_;
	}
	bool IsSynchronized() const {
	return is_synchronized_;
	}
	bool IsParamALongOrDouble(unsigned int param) const {
	DCHECK_LT(param, NumArgs());
	if (IsStatic()) {
	param++; // 0th argument must skip return value at start of the shorty
	} else if (param == 0) {
	return false; // this argument
	}
	char ch = shorty_[param];
	return (ch == 'J' \|\| ch == 'D');
	}
	bool IsParamAReference(unsigned int param) const {
	DCHECK_LT(param, NumArgs());
	if (IsStatic()) {
	param++; // 0th argument must skip return value at start of the shorty
	} else if (param == 0) {
	return true; // this argument
	}
	return shorty_[param] == 'L';
	}
	size_t NumArgs() const {
	return num_args_;
	}
	size_t NumLongOrDoubleArgs() const {
	return num_long_or_double_args_;
	}
	size_t NumReferenceArgs() const {
	return num_ref_args_;
	}
	size_t ParamSize(unsigned int param) const {
	DCHECK_LT(param, NumArgs());
	if (IsStatic()) {
	param++; // 0th argument must skip return value at start of the shorty
	} else if (param == 0) {
	return kPointerSize; // this argument
	}
	size_t result = Primitive::ComponentSize(Primitive::GetType(shorty_[param]));
	if (result >= 1 && result < 4) {
	result = 4;
	}
	return result;
	}
	const char* GetShorty() const {
	return shorty_.c_str();
	}
	// The slot number for current calling_convention argument.
	// Note that each slot is 32-bit. When the current argument is bigger
	// than 32 bits, return the first slot number for this argument.
	unsigned int itr_slots_;
	// The number of references iterated past
	unsigned int itr_refs_;
	// The argument number along argument list for current argument
	unsigned int itr_args_;
	// Number of longs and doubles seen along argument list
	unsigned int itr_longs_and_doubles_;
	// Space for frames below this on the stack
	FrameOffset displacement_;

	private:
	const bool is_static_;
	const bool is_synchronized_;
	std::string shorty_;
	size_t num_args_;
	size_t num_ref_args_;
	size_t num_long_or_double_args_;
	};

	// Abstraction for managed code's calling conventions
	// \| { Incoming stack args } \|
	// \| { Prior Method* } \| <-- Prior SP
	// \| { Return address } \|
	// \| { Callee saves } \|
	// \| { Spills ... } \|
	// \| { Outgoing stack args } \|
	// \| { Method* } \| <-- SP
	class ManagedRuntimeCallingConvention : public CallingConvention {
	public:
	static ManagedRuntimeCallingConvention* Create(bool is_static, bool is_synchronized,
	const char* shorty,
	InstructionSet instruction_set);

	// Register that holds the incoming method argument
	virtual ManagedRegister MethodRegister() = 0;

	// Iterator interface
	bool HasNext();
	void Next();
	bool IsCurrentParamAReference();
	bool IsCurrentArgExplicit(); // ie a non-implict argument such as this
	bool IsCurrentArgPossiblyNull();
	size_t CurrentParamSize();
	virtual bool IsCurrentParamInRegister() = 0;
	virtual bool IsCurrentParamOnStack() = 0;
	virtual ManagedRegister CurrentParamRegister() = 0;
	virtual FrameOffset CurrentParamStackOffset() = 0;

	virtual ~ManagedRuntimeCallingConvention() {}

	// Registers to spill to caller's out registers on entry.
	virtual const std::vector<ManagedRegister>& EntrySpills() = 0;

	protected:
	ManagedRuntimeCallingConvention(bool is_static, bool is_synchronized, const char* shorty) :
	CallingConvention(is_static, is_synchronized, shorty) {}
	};

	// Abstraction for JNI calling conventions
	// \| { Incoming stack args } \| <-- Prior SP
	// \| { Return address } \|
	// \| { Callee saves } \| ([1])
	// \| { Return value spill } \| (live on return slow paths)
	// \| { Local Ref. Table State } \|
	// \| { Stack Indirect Ref. Table \|
	// \| num. refs./link } \| (here to prior SP is frame size)
	// \| { Method* } \| <-- Anchor SP written to thread
	// \| { Outgoing stack args } \| <-- SP at point of call
	// \| Native frame \|
	//
	// [1] We must save all callee saves here to enable any exception throws to restore
	// callee saves for frames above this one.
	class JniCallingConvention : public CallingConvention {
	public:
	static JniCallingConvention* Create(bool is_static, bool is_synchronized, const char* shorty,
	InstructionSet instruction_set);

	// Size of frame excluding space for outgoing args (its assumed Method* is
	// always at the bottom of a frame, but this doesn't work for outgoing
	// native args). Includes alignment.
	virtual size_t FrameSize() = 0;
	// Size of outgoing arguments, including alignment
	virtual size_t OutArgSize() = 0;
	// Number of references in stack indirect reference table
	size_t ReferenceCount() const;
	// Location where the segment state of the local indirect reference table is saved
	FrameOffset SavedLocalReferenceCookieOffset() const;
	// Location where the return value of a call can be squirreled if another
	// call is made following the native call
	FrameOffset ReturnValueSaveLocation() const;

	// Callee save registers to spill prior to native code (which may clobber)
	virtual const std::vector<ManagedRegister>& CalleeSaveRegisters() const = 0;

	// Spill mask values
	virtual uint32_t CoreSpillMask() const = 0;
	virtual uint32_t FpSpillMask() const = 0;

	// Returns true if the method register will have been clobbered during argument
	// set up
	virtual bool IsMethodRegisterClobberedPreCall() = 0;

	// An extra scratch register live after the call
	virtual ManagedRegister ReturnScratchRegister() const = 0;

	// Iterator interface
	bool HasNext();
	virtual void Next();
	bool IsCurrentParamAReference();
	size_t CurrentParamSize();
	virtual bool IsCurrentParamInRegister() = 0;
	virtual bool IsCurrentParamOnStack() = 0;
	virtual ManagedRegister CurrentParamRegister() = 0;
	virtual FrameOffset CurrentParamStackOffset() = 0;

	// Iterator interface extension for JNI
	FrameOffset CurrentParamSirtEntryOffset();

	// Position of SIRT and interior fields
	FrameOffset SirtOffset() const {
	return FrameOffset(displacement_.Int32Value() +
	kPointerSize); // above Method*
	}
	FrameOffset SirtNumRefsOffset() const {
	return FrameOffset(SirtOffset().Int32Value() +
	StackIndirectReferenceTable::NumberOfReferencesOffset());
	}
	FrameOffset SirtLinkOffset() const {
	return FrameOffset(SirtOffset().Int32Value() +
	StackIndirectReferenceTable::LinkOffset());
	}

	virtual ~JniCallingConvention() {}

	protected:
	// Named iterator positions
	enum IteratorPos {
	kJniEnv = 0,
	kObjectOrClass = 1
	};

	explicit JniCallingConvention(bool is_static, bool is_synchronized, const char* shorty) :
	CallingConvention(is_static, is_synchronized, shorty) {}

	// Number of stack slots for outgoing arguments, above which the SIRT is
	// located
	virtual size_t NumberOfOutgoingStackArgs() = 0;

	protected:
	size_t NumberOfExtraArgumentsForJni();
	};

	} // namespace art

	#endif // ART_SRC_CALLING_CONVENTION_H_