| /* |
| * 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. |
| */ |
| |
| #include "calling_convention_arm.h" |
| #include "logging.h" |
| #include "managed_register_arm.h" |
| |
| namespace art { |
| namespace arm { |
| |
| // Calling convention |
| |
| ManagedRegister ArmManagedRuntimeCallingConvention::InterproceduralScratchRegister() { |
| return ArmManagedRegister::FromCoreRegister(IP); // R12 |
| } |
| |
| ManagedRegister ArmJniCallingConvention::InterproceduralScratchRegister() { |
| return ArmManagedRegister::FromCoreRegister(IP); // R12 |
| } |
| |
| static ManagedRegister ReturnRegisterForShorty(const char* shorty) { |
| if (shorty[0] == 'F') { |
| return ArmManagedRegister::FromCoreRegister(R0); |
| } else if (shorty[0] == 'D') { |
| return ArmManagedRegister::FromRegisterPair(R0_R1); |
| } else if (shorty[0] == 'J') { |
| return ArmManagedRegister::FromRegisterPair(R0_R1); |
| } else if (shorty[0] == 'V') { |
| return ArmManagedRegister::NoRegister(); |
| } else { |
| return ArmManagedRegister::FromCoreRegister(R0); |
| } |
| } |
| |
| ManagedRegister ArmManagedRuntimeCallingConvention::ReturnRegister() { |
| return ReturnRegisterForShorty(GetShorty()); |
| } |
| |
| ManagedRegister ArmJniCallingConvention::ReturnRegister() { |
| return ReturnRegisterForShorty(GetShorty()); |
| } |
| |
| // Managed runtime calling convention |
| |
| ManagedRegister ArmManagedRuntimeCallingConvention::MethodRegister() { |
| return ArmManagedRegister::FromCoreRegister(R0); |
| } |
| |
| bool ArmManagedRuntimeCallingConvention::IsCurrentParamInRegister() { |
| return itr_slots_ < 3; |
| } |
| |
| bool ArmManagedRuntimeCallingConvention::IsCurrentParamOnStack() { |
| if (itr_slots_ < 2) { |
| return false; |
| } else if (itr_slots_ > 2) { |
| return true; |
| } else { |
| // handle funny case of a long/double straddling registers and the stack |
| return IsParamALongOrDouble(itr_args_); |
| } |
| } |
| |
| static const Register kManagedArgumentRegisters[] = { |
| R1, R2, R3 |
| }; |
| ManagedRegister ArmManagedRuntimeCallingConvention::CurrentParamRegister() { |
| CHECK(IsCurrentParamInRegister()); |
| if (IsParamALongOrDouble(itr_args_)) { |
| if (itr_slots_ == 0) { |
| return ArmManagedRegister::FromRegisterPair(R1_R2); |
| } else if (itr_slots_ == 1) { |
| return ArmManagedRegister::FromRegisterPair(R2_R3); |
| } else { |
| // This is a long/double split between registers and the stack |
| return ArmManagedRegister::FromCoreRegister( |
| kManagedArgumentRegisters[itr_slots_]); |
| } |
| } else { |
| return |
| ArmManagedRegister::FromCoreRegister(kManagedArgumentRegisters[itr_slots_]); |
| } |
| } |
| |
| FrameOffset ArmManagedRuntimeCallingConvention::CurrentParamStackOffset() { |
| CHECK(IsCurrentParamOnStack()); |
| FrameOffset result = |
| FrameOffset(displacement_.Int32Value() + // displacement |
| kPointerSize + // Method* |
| (itr_slots_ * kPointerSize)); // offset into in args |
| if (itr_slots_ == 2) { |
| // the odd spanning case, bump the offset to skip the first half of the |
| // input which is in a register |
| CHECK(IsCurrentParamInRegister()); |
| result = FrameOffset(result.Int32Value() + 4); |
| } |
| return result; |
| } |
| |
| // JNI calling convention |
| |
| ArmJniCallingConvention::ArmJniCallingConvention(bool is_static, bool is_synchronized, |
| const char* shorty) |
| : JniCallingConvention(is_static, is_synchronized, shorty) { |
| // Compute padding to ensure longs and doubles are not split in AAPCS. Ignore the 'this' jobject |
| // or jclass for static methods and the JNIEnv. We start at the aligned register r2. |
| size_t padding = 0; |
| for (size_t cur_arg = IsStatic() ? 0 : 1, cur_reg = 2; cur_arg < NumArgs(); cur_arg++) { |
| if (IsParamALongOrDouble(cur_arg)) { |
| if ((cur_reg & 1) != 0) { |
| padding += 4; |
| cur_reg++; // additional bump to ensure alignment |
| } |
| cur_reg++; // additional bump to skip extra long word |
| } |
| cur_reg++; // bump the iterator for every argument |
| } |
| padding_ = padding; |
| |
| callee_save_regs_.push_back(ArmManagedRegister::FromCoreRegister(R5)); |
| callee_save_regs_.push_back(ArmManagedRegister::FromCoreRegister(R6)); |
| callee_save_regs_.push_back(ArmManagedRegister::FromCoreRegister(R7)); |
| callee_save_regs_.push_back(ArmManagedRegister::FromCoreRegister(R8)); |
| callee_save_regs_.push_back(ArmManagedRegister::FromCoreRegister(R10)); |
| callee_save_regs_.push_back(ArmManagedRegister::FromCoreRegister(R11)); |
| } |
| |
| uint32_t ArmJniCallingConvention::CoreSpillMask() const { |
| // Compute spill mask to agree with callee saves initialized in the constructor |
| uint32_t result = 0; |
| result = 1 << R5 | 1 << R6 | 1 << R7 | 1 << R8 | 1 << R10 | 1 << R11 | 1 << LR; |
| return result; |
| } |
| |
| ManagedRegister ArmJniCallingConvention::ReturnScratchRegister() const { |
| return ArmManagedRegister::FromCoreRegister(R2); |
| } |
| |
| size_t ArmJniCallingConvention::FrameSize() { |
| // Method*, LR and callee save area size, local reference segment state |
| size_t frame_data_size = (3 + CalleeSaveRegisters().size()) * kPointerSize; |
| // References plus 2 words for SIRT header |
| size_t sirt_size = (ReferenceCount() + 2) * kPointerSize; |
| // Plus return value spill area size |
| return RoundUp(frame_data_size + sirt_size + SizeOfReturnValue(), kStackAlignment); |
| } |
| |
| size_t ArmJniCallingConvention::OutArgSize() { |
| return RoundUp(NumberOfOutgoingStackArgs() * kPointerSize + padding_, |
| kStackAlignment); |
| } |
| |
| // Will reg be crushed by an outgoing argument? |
| bool ArmJniCallingConvention::IsMethodRegisterClobberedPreCall() { |
| return true; // The method register R0 is always clobbered by the JNIEnv |
| } |
| |
| // JniCallingConvention ABI follows AAPCS where longs and doubles must occur |
| // in even register numbers and stack slots |
| void ArmJniCallingConvention::Next() { |
| JniCallingConvention::Next(); |
| size_t arg_pos = itr_args_ - NumberOfExtraArgumentsForJni(); |
| if ((itr_args_ >= 2) && |
| (arg_pos < NumArgs()) && |
| IsParamALongOrDouble(arg_pos)) { |
| // itr_slots_ needs to be an even number, according to AAPCS. |
| if ((itr_slots_ & 0x1u) != 0) { |
| itr_slots_++; |
| } |
| } |
| } |
| |
| bool ArmJniCallingConvention::IsCurrentParamInRegister() { |
| return itr_slots_ < 4; |
| } |
| |
| bool ArmJniCallingConvention::IsCurrentParamOnStack() { |
| return !IsCurrentParamInRegister(); |
| } |
| |
| static const Register kJniArgumentRegisters[] = { |
| R0, R1, R2, R3 |
| }; |
| ManagedRegister ArmJniCallingConvention::CurrentParamRegister() { |
| CHECK_LT(itr_slots_, 4u); |
| int arg_pos = itr_args_ - NumberOfExtraArgumentsForJni(); |
| if ((itr_args_ >= 2) && IsParamALongOrDouble(arg_pos)) { |
| CHECK_EQ(itr_slots_, 2u); |
| return ArmManagedRegister::FromRegisterPair(R2_R3); |
| } else { |
| return |
| ArmManagedRegister::FromCoreRegister(kJniArgumentRegisters[itr_slots_]); |
| } |
| } |
| |
| FrameOffset ArmJniCallingConvention::CurrentParamStackOffset() { |
| CHECK_GE(itr_slots_, 4u); |
| size_t offset = displacement_.Int32Value() - OutArgSize() + ((itr_slots_ - 4) * kPointerSize); |
| CHECK_LT(offset, OutArgSize()); |
| return FrameOffset(offset); |
| } |
| |
| size_t ArmJniCallingConvention::NumberOfOutgoingStackArgs() { |
| size_t static_args = IsStatic() ? 1 : 0; // count jclass |
| // regular argument parameters and this |
| size_t param_args = NumArgs() + NumLongOrDoubleArgs(); |
| // count JNIEnv* less arguments in registers |
| return static_args + param_args + 1 - 4; |
| } |
| |
| } // namespace arm |
| } // namespace art |