compiler/jni/quick/arm64/calling_convention_arm64.cc - platform/art - Git at Google

 /*
  * Copyright (C) 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.
  */

 #include "base/logging.h"
 #include "calling_convention_arm64.h"
 #include "handle_scope-inl.h"
 #include "utils/arm64/managed_register_arm64.h"

 namespace art {
 namespace arm64 {

 static const XRegister kXArgumentRegisters[] = {
   X0, X1, X2, X3, X4, X5, X6, X7
 };

 static const WRegister kWArgumentRegisters[] = {
   W0, W1, W2, W3, W4, W5, W6, W7
 };

 static const DRegister kDArgumentRegisters[] = {
   D0, D1, D2, D3, D4, D5, D6, D7
 };

 static const SRegister kSArgumentRegisters[] = {
   S0, S1, S2, S3, S4, S5, S6, S7
 };

 static const DRegister kDCalleeSaveRegisters[] = {
   D8, D9, D10, D11, D12, D13, D14, D15
 };

 // Calling convention
 ManagedRegister Arm64ManagedRuntimeCallingConvention::InterproceduralScratchRegister() {
   return Arm64ManagedRegister::FromXRegister(X20);  // saved on entry restored on exit
 }

 ManagedRegister Arm64JniCallingConvention::InterproceduralScratchRegister() {
   return Arm64ManagedRegister::FromXRegister(X20);  // saved on entry restored on exit
 }

 static ManagedRegister ReturnRegisterForShorty(const char* shorty) {
   if (shorty[0] == 'F') {
     return Arm64ManagedRegister::FromSRegister(S0);
   } else if (shorty[0] == 'D') {
     return Arm64ManagedRegister::FromDRegister(D0);
   } else if (shorty[0] == 'J') {
     return Arm64ManagedRegister::FromXRegister(X0);
   } else if (shorty[0] == 'V') {
     return Arm64ManagedRegister::NoRegister();
   } else {
     return Arm64ManagedRegister::FromWRegister(W0);
   }
 }

 ManagedRegister Arm64ManagedRuntimeCallingConvention::ReturnRegister() {
   return ReturnRegisterForShorty(GetShorty());
 }

 ManagedRegister Arm64JniCallingConvention::ReturnRegister() {
   return ReturnRegisterForShorty(GetShorty());
 }

 ManagedRegister Arm64JniCallingConvention::IntReturnRegister() {
   return Arm64ManagedRegister::FromWRegister(W0);
 }

 // Managed runtime calling convention

 ManagedRegister Arm64ManagedRuntimeCallingConvention::MethodRegister() {
   return Arm64ManagedRegister::FromXRegister(X0);
 }

 bool Arm64ManagedRuntimeCallingConvention::IsCurrentParamInRegister() {
   return false;  // Everything moved to stack on entry.
 }

 bool Arm64ManagedRuntimeCallingConvention::IsCurrentParamOnStack() {
   return true;
 }

 ManagedRegister Arm64ManagedRuntimeCallingConvention::CurrentParamRegister() {
   LOG(FATAL) << "Should not reach here";
   return ManagedRegister::NoRegister();
 }

 FrameOffset Arm64ManagedRuntimeCallingConvention::CurrentParamStackOffset() {
   CHECK(IsCurrentParamOnStack());
   FrameOffset result =
       FrameOffset(displacement_.Int32Value() +  // displacement
                   kFramePointerSize +  // Method ref
                   (itr_slots_ * sizeof(uint32_t)));  // offset into in args
   return result;
 }

 const ManagedRegisterEntrySpills& Arm64ManagedRuntimeCallingConvention::EntrySpills() {
   // We spill the argument registers on ARM64 to free them up for scratch use, we then assume
   // all arguments are on the stack.
   if ((entry_spills_.size() == 0) && (NumArgs() > 0)) {
     int gp_reg_index = 1;   // we start from X1/W1, X0 holds ArtMethod*.
     int fp_reg_index = 0;   // D0/S0.

     // We need to choose the correct register (D/S or X/W) since the managed
     // stack uses 32bit stack slots.
     ResetIterator(FrameOffset(0));
     while (HasNext()) {
       if (IsCurrentParamAFloatOrDouble()) {  // FP regs.
           if (fp_reg_index < 8) {
             if (!IsCurrentParamADouble()) {
               entry_spills_.push_back(Arm64ManagedRegister::FromSRegister(kSArgumentRegisters[fp_reg_index]));
             } else {
               entry_spills_.push_back(Arm64ManagedRegister::FromDRegister(kDArgumentRegisters[fp_reg_index]));
             }
             fp_reg_index++;
           } else {  // just increase the stack offset.
             if (!IsCurrentParamADouble()) {
               entry_spills_.push_back(ManagedRegister::NoRegister(), 4);
             } else {
               entry_spills_.push_back(ManagedRegister::NoRegister(), 8);
             }
           }
       } else {  // GP regs.
         if (gp_reg_index < 8) {
           if (IsCurrentParamALong() && (!IsCurrentParamAReference())) {
             entry_spills_.push_back(Arm64ManagedRegister::FromXRegister(kXArgumentRegisters[gp_reg_index]));
           } else {
             entry_spills_.push_back(Arm64ManagedRegister::FromWRegister(kWArgumentRegisters[gp_reg_index]));
           }
           gp_reg_index++;
         } else {  // just increase the stack offset.
           if (IsCurrentParamALong() && (!IsCurrentParamAReference())) {
               entry_spills_.push_back(ManagedRegister::NoRegister(), 8);
           } else {
               entry_spills_.push_back(ManagedRegister::NoRegister(), 4);
           }
         }
       }
       Next();
     }
   }
   return entry_spills_;
 }

 // JNI calling convention
 Arm64JniCallingConvention::Arm64JniCallingConvention(bool is_static, bool is_synchronized,
                                                      const char* shorty)
     : JniCallingConvention(is_static, is_synchronized, shorty, kFramePointerSize) {
   uint32_t core_spill_mask = CoreSpillMask();
   DCHECK_EQ(XZR, kNumberOfXRegisters - 1);  // Exclude XZR from the loop (avoid 1 << 32).
   for (int x_reg = 0; x_reg < kNumberOfXRegisters - 1; ++x_reg) {
     if (((1 << x_reg) & core_spill_mask) != 0) {
       callee_save_regs_.push_back(
           Arm64ManagedRegister::FromXRegister(static_cast<XRegister>(x_reg)));
     }
   }

   uint32_t fp_spill_mask = FpSpillMask();
   for (int d_reg = 0; d_reg < kNumberOfDRegisters; ++d_reg) {
     if (((1 << d_reg) & fp_spill_mask) != 0) {
       callee_save_regs_.push_back(
           Arm64ManagedRegister::FromDRegister(static_cast<DRegister>(d_reg)));
     }
   }
 }

 uint32_t Arm64JniCallingConvention::CoreSpillMask() const {
   // Compute spill mask to agree with callee saves initialized in the constructor.
   // Note: The native jni function may call to some VM runtime functions which may suspend
   // or trigger GC. And the jni method frame will become top quick frame in those cases.
   // So we need to satisfy GC to save LR and callee-save registers which is similar to
   // CalleeSaveMethod(RefOnly) frame.
   // Jni function is the native function which the java code wants to call.
   // Jni method is the method that compiled by jni compiler.
   // Call chain: managed code(java) --> jni method --> jni function.
   // Thread register(X18, scratched by aapcs64) is not saved on stack, it is saved in ETR(X21).
   return 1 << X19 | 1 << X20 | 1 << X21 | 1 << X22 | 1 << X23 | 1 << X24 |
          1 << X25 | 1 << X26 | 1 << X27 | 1 << X28 | 1 << X29 | 1 << LR;
 }

 uint32_t Arm64JniCallingConvention::FpSpillMask() const {
   // Considering the case, java_method_1 --> jni method --> jni function --> java_method_2, we may
   // break on java_method_2 and we still need to find out the values of DEX registers in
   // java_method_1. So all callee-saves(in managed code) need to be saved.
   uint32_t result = 0;
   for (size_t i = 0; i < arraysize(kDCalleeSaveRegisters); ++i) {
     result |= (1 << kDCalleeSaveRegisters[i]);
   }
   return result;
 }

 ManagedRegister Arm64JniCallingConvention::ReturnScratchRegister() const {
   return ManagedRegister::NoRegister();
 }

 size_t Arm64JniCallingConvention::FrameSize() {
   // Method*, callee save area size, local reference segment state
   size_t frame_data_size = kFramePointerSize +
       CalleeSaveRegisters().size() * kFramePointerSize + sizeof(uint32_t);
   // References plus 2 words for HandleScope header
   size_t handle_scope_size = HandleScope::SizeOf(kFramePointerSize, ReferenceCount());
   // Plus return value spill area size
   return RoundUp(frame_data_size + handle_scope_size + SizeOfReturnValue(), kStackAlignment);
 }

 size_t Arm64JniCallingConvention::OutArgSize() {
   return RoundUp(NumberOfOutgoingStackArgs() * kFramePointerSize, kStackAlignment);
 }

 bool Arm64JniCallingConvention::IsCurrentParamInRegister() {
   if (IsCurrentParamAFloatOrDouble()) {
     return (itr_float_and_doubles_ < 8);
   } else {
     return ((itr_args_ - itr_float_and_doubles_) < 8);
   }
 }

 bool Arm64JniCallingConvention::IsCurrentParamOnStack() {
   return !IsCurrentParamInRegister();
 }

 ManagedRegister Arm64JniCallingConvention::CurrentParamRegister() {
   CHECK(IsCurrentParamInRegister());
   if (IsCurrentParamAFloatOrDouble()) {
     CHECK_LT(itr_float_and_doubles_, 8u);
     if (IsCurrentParamADouble()) {
       return Arm64ManagedRegister::FromDRegister(kDArgumentRegisters[itr_float_and_doubles_]);
     } else {
       return Arm64ManagedRegister::FromSRegister(kSArgumentRegisters[itr_float_and_doubles_]);
     }
   } else {
     int gp_reg = itr_args_ - itr_float_and_doubles_;
     CHECK_LT(static_cast<unsigned int>(gp_reg), 8u);
     if (IsCurrentParamALong() || IsCurrentParamAReference() || IsCurrentParamJniEnv())  {
       return Arm64ManagedRegister::FromXRegister(kXArgumentRegisters[gp_reg]);
     } else {
       return Arm64ManagedRegister::FromWRegister(kWArgumentRegisters[gp_reg]);
     }
   }
 }

 FrameOffset Arm64JniCallingConvention::CurrentParamStackOffset() {
   CHECK(IsCurrentParamOnStack());
   size_t args_on_stack = itr_args_
                   - std::min(8u, itr_float_and_doubles_)
                   - std::min(8u, (itr_args_ - itr_float_and_doubles_));
   size_t offset = displacement_.Int32Value() - OutArgSize() + (args_on_stack * kFramePointerSize);
   CHECK_LT(offset, OutArgSize());
   return FrameOffset(offset);
 }

 size_t Arm64JniCallingConvention::NumberOfOutgoingStackArgs() {
   // all arguments including JNI args
   size_t all_args = NumArgs() + NumberOfExtraArgumentsForJni();

   size_t all_stack_args = all_args -
             std::min(8u, static_cast<unsigned int>(NumFloatOrDoubleArgs())) -
             std::min(8u, static_cast<unsigned int>((all_args - NumFloatOrDoubleArgs())));

   return all_stack_args;
 }

 }  // namespace arm64
 }  // namespace art
	/*
	* Copyright (C) 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.
	*/

	#include "base/logging.h"
	#include "calling_convention_arm64.h"
	#include "handle_scope-inl.h"
	#include "utils/arm64/managed_register_arm64.h"

	namespace art {
	namespace arm64 {

	static const XRegister kXArgumentRegisters[] = {
	X0, X1, X2, X3, X4, X5, X6, X7
	};

	static const WRegister kWArgumentRegisters[] = {
	W0, W1, W2, W3, W4, W5, W6, W7
	};

	static const DRegister kDArgumentRegisters[] = {
	D0, D1, D2, D3, D4, D5, D6, D7
	};

	static const SRegister kSArgumentRegisters[] = {
	S0, S1, S2, S3, S4, S5, S6, S7
	};

	static const DRegister kDCalleeSaveRegisters[] = {
	D8, D9, D10, D11, D12, D13, D14, D15
	};

	// Calling convention
	ManagedRegister Arm64ManagedRuntimeCallingConvention::InterproceduralScratchRegister() {
	return Arm64ManagedRegister::FromXRegister(X20); // saved on entry restored on exit
	}

	ManagedRegister Arm64JniCallingConvention::InterproceduralScratchRegister() {
	return Arm64ManagedRegister::FromXRegister(X20); // saved on entry restored on exit
	}

	static ManagedRegister ReturnRegisterForShorty(const char* shorty) {
	if (shorty[0] == 'F') {
	return Arm64ManagedRegister::FromSRegister(S0);
	} else if (shorty[0] == 'D') {
	return Arm64ManagedRegister::FromDRegister(D0);
	} else if (shorty[0] == 'J') {
	return Arm64ManagedRegister::FromXRegister(X0);
	} else if (shorty[0] == 'V') {
	return Arm64ManagedRegister::NoRegister();
	} else {
	return Arm64ManagedRegister::FromWRegister(W0);
	}
	}

	ManagedRegister Arm64ManagedRuntimeCallingConvention::ReturnRegister() {
	return ReturnRegisterForShorty(GetShorty());
	}

	ManagedRegister Arm64JniCallingConvention::ReturnRegister() {
	return ReturnRegisterForShorty(GetShorty());
	}

	ManagedRegister Arm64JniCallingConvention::IntReturnRegister() {
	return Arm64ManagedRegister::FromWRegister(W0);
	}

	// Managed runtime calling convention

	ManagedRegister Arm64ManagedRuntimeCallingConvention::MethodRegister() {
	return Arm64ManagedRegister::FromXRegister(X0);
	}

	bool Arm64ManagedRuntimeCallingConvention::IsCurrentParamInRegister() {
	return false; // Everything moved to stack on entry.
	}

	bool Arm64ManagedRuntimeCallingConvention::IsCurrentParamOnStack() {
	return true;
	}

	ManagedRegister Arm64ManagedRuntimeCallingConvention::CurrentParamRegister() {
	LOG(FATAL) << "Should not reach here";
	return ManagedRegister::NoRegister();
	}

	FrameOffset Arm64ManagedRuntimeCallingConvention::CurrentParamStackOffset() {
	CHECK(IsCurrentParamOnStack());
	FrameOffset result =
	FrameOffset(displacement_.Int32Value() + // displacement
	kFramePointerSize + // Method ref
	(itr_slots_ * sizeof(uint32_t))); // offset into in args
	return result;
	}

	const ManagedRegisterEntrySpills& Arm64ManagedRuntimeCallingConvention::EntrySpills() {
	// We spill the argument registers on ARM64 to free them up for scratch use, we then assume
	// all arguments are on the stack.
	if ((entry_spills_.size() == 0) && (NumArgs() > 0)) {
	int gp_reg_index = 1; // we start from X1/W1, X0 holds ArtMethod*.
	int fp_reg_index = 0; // D0/S0.

	// We need to choose the correct register (D/S or X/W) since the managed
	// stack uses 32bit stack slots.
	ResetIterator(FrameOffset(0));
	while (HasNext()) {
	if (IsCurrentParamAFloatOrDouble()) { // FP regs.
	if (fp_reg_index < 8) {
	if (!IsCurrentParamADouble()) {
	entry_spills_.push_back(Arm64ManagedRegister::FromSRegister(kSArgumentRegisters[fp_reg_index]));
	} else {
	entry_spills_.push_back(Arm64ManagedRegister::FromDRegister(kDArgumentRegisters[fp_reg_index]));
	}
	fp_reg_index++;
	} else { // just increase the stack offset.
	if (!IsCurrentParamADouble()) {
	entry_spills_.push_back(ManagedRegister::NoRegister(), 4);
	} else {
	entry_spills_.push_back(ManagedRegister::NoRegister(), 8);
	}
	}
	} else { // GP regs.
	if (gp_reg_index < 8) {
	if (IsCurrentParamALong() && (!IsCurrentParamAReference())) {
	entry_spills_.push_back(Arm64ManagedRegister::FromXRegister(kXArgumentRegisters[gp_reg_index]));
	} else {
	entry_spills_.push_back(Arm64ManagedRegister::FromWRegister(kWArgumentRegisters[gp_reg_index]));
	}
	gp_reg_index++;
	} else { // just increase the stack offset.
	if (IsCurrentParamALong() && (!IsCurrentParamAReference())) {
	entry_spills_.push_back(ManagedRegister::NoRegister(), 8);
	} else {
	entry_spills_.push_back(ManagedRegister::NoRegister(), 4);
	}
	}
	}
	Next();
	}
	}
	return entry_spills_;
	}

	// JNI calling convention
	Arm64JniCallingConvention::Arm64JniCallingConvention(bool is_static, bool is_synchronized,
	const char* shorty)
	: JniCallingConvention(is_static, is_synchronized, shorty, kFramePointerSize) {
	uint32_t core_spill_mask = CoreSpillMask();
	DCHECK_EQ(XZR, kNumberOfXRegisters - 1); // Exclude XZR from the loop (avoid 1 << 32).
	for (int x_reg = 0; x_reg < kNumberOfXRegisters - 1; ++x_reg) {
	if (((1 << x_reg) & core_spill_mask) != 0) {
	callee_save_regs_.push_back(
	Arm64ManagedRegister::FromXRegister(static_cast<XRegister>(x_reg)));
	}
	}

	uint32_t fp_spill_mask = FpSpillMask();
	for (int d_reg = 0; d_reg < kNumberOfDRegisters; ++d_reg) {
	if (((1 << d_reg) & fp_spill_mask) != 0) {
	callee_save_regs_.push_back(
	Arm64ManagedRegister::FromDRegister(static_cast<DRegister>(d_reg)));
	}
	}
	}

	uint32_t Arm64JniCallingConvention::CoreSpillMask() const {
	// Compute spill mask to agree with callee saves initialized in the constructor.
	// Note: The native jni function may call to some VM runtime functions which may suspend
	// or trigger GC. And the jni method frame will become top quick frame in those cases.
	// So we need to satisfy GC to save LR and callee-save registers which is similar to
	// CalleeSaveMethod(RefOnly) frame.
	// Jni function is the native function which the java code wants to call.
	// Jni method is the method that compiled by jni compiler.
	// Call chain: managed code(java) --> jni method --> jni function.
	// Thread register(X18, scratched by aapcs64) is not saved on stack, it is saved in ETR(X21).
	return 1 << X19 \| 1 << X20 \| 1 << X21 \| 1 << X22 \| 1 << X23 \| 1 << X24 \|
	1 << X25 \| 1 << X26 \| 1 << X27 \| 1 << X28 \| 1 << X29 \| 1 << LR;
	}

	uint32_t Arm64JniCallingConvention::FpSpillMask() const {
	// Considering the case, java_method_1 --> jni method --> jni function --> java_method_2, we may
	// break on java_method_2 and we still need to find out the values of DEX registers in
	// java_method_1. So all callee-saves(in managed code) need to be saved.
	uint32_t result = 0;
	for (size_t i = 0; i < arraysize(kDCalleeSaveRegisters); ++i) {
	result \|= (1 << kDCalleeSaveRegisters[i]);
	}
	return result;
	}

	ManagedRegister Arm64JniCallingConvention::ReturnScratchRegister() const {
	return ManagedRegister::NoRegister();
	}

	size_t Arm64JniCallingConvention::FrameSize() {
	// Method*, callee save area size, local reference segment state
	size_t frame_data_size = kFramePointerSize +
	CalleeSaveRegisters().size() * kFramePointerSize + sizeof(uint32_t);
	// References plus 2 words for HandleScope header
	size_t handle_scope_size = HandleScope::SizeOf(kFramePointerSize, ReferenceCount());
	// Plus return value spill area size
	return RoundUp(frame_data_size + handle_scope_size + SizeOfReturnValue(), kStackAlignment);
	}

	size_t Arm64JniCallingConvention::OutArgSize() {
	return RoundUp(NumberOfOutgoingStackArgs() * kFramePointerSize, kStackAlignment);
	}

	bool Arm64JniCallingConvention::IsCurrentParamInRegister() {
	if (IsCurrentParamAFloatOrDouble()) {
	return (itr_float_and_doubles_ < 8);
	} else {
	return ((itr_args_ - itr_float_and_doubles_) < 8);
	}
	}

	bool Arm64JniCallingConvention::IsCurrentParamOnStack() {
	return !IsCurrentParamInRegister();
	}

	ManagedRegister Arm64JniCallingConvention::CurrentParamRegister() {
	CHECK(IsCurrentParamInRegister());
	if (IsCurrentParamAFloatOrDouble()) {
	CHECK_LT(itr_float_and_doubles_, 8u);
	if (IsCurrentParamADouble()) {
	return Arm64ManagedRegister::FromDRegister(kDArgumentRegisters[itr_float_and_doubles_]);
	} else {
	return Arm64ManagedRegister::FromSRegister(kSArgumentRegisters[itr_float_and_doubles_]);
	}
	} else {
	int gp_reg = itr_args_ - itr_float_and_doubles_;
	CHECK_LT(static_cast<unsigned int>(gp_reg), 8u);
	if (IsCurrentParamALong() \|\| IsCurrentParamAReference() \|\| IsCurrentParamJniEnv()) {
	return Arm64ManagedRegister::FromXRegister(kXArgumentRegisters[gp_reg]);
	} else {
	return Arm64ManagedRegister::FromWRegister(kWArgumentRegisters[gp_reg]);
	}
	}
	}

	FrameOffset Arm64JniCallingConvention::CurrentParamStackOffset() {
	CHECK(IsCurrentParamOnStack());
	size_t args_on_stack = itr_args_
	- std::min(8u, itr_float_and_doubles_)
	- std::min(8u, (itr_args_ - itr_float_and_doubles_));
	size_t offset = displacement_.Int32Value() - OutArgSize() + (args_on_stack * kFramePointerSize);
	CHECK_LT(offset, OutArgSize());
	return FrameOffset(offset);
	}

	size_t Arm64JniCallingConvention::NumberOfOutgoingStackArgs() {
	// all arguments including JNI args
	size_t all_args = NumArgs() + NumberOfExtraArgumentsForJni();

	size_t all_stack_args = all_args -
	std::min(8u, static_cast<unsigned int>(NumFloatOrDoubleArgs())) -
	std::min(8u, static_cast<unsigned int>((all_args - NumFloatOrDoubleArgs())));

	return all_stack_args;
	}

	} // namespace arm64
	} // namespace art