Home | History | Annotate | Download | only in x86 
      1 /*
      2  * Copyright (C) 2011 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 
     17 #include "calling_convention_x86.h"
     18 
     19 #include "base/logging.h"
     20 #include "utils/x86/managed_register_x86.h"
     21 #include "utils.h"
     22 
     23 namespace art {
     24 namespace x86 {
     25 
     26 // Calling convention
     27 
     28 ManagedRegister X86ManagedRuntimeCallingConvention::InterproceduralScratchRegister() {
     29   return X86ManagedRegister::FromCpuRegister(ECX);
     30 }
     31 
     32 ManagedRegister X86JniCallingConvention::InterproceduralScratchRegister() {
     33   return X86ManagedRegister::FromCpuRegister(ECX);
     34 }
     35 
     36 ManagedRegister X86JniCallingConvention::ReturnScratchRegister() const {
     37   return ManagedRegister::NoRegister();  // No free regs, so assembler uses push/pop
     38 }
     39 
     40 static ManagedRegister ReturnRegisterForShorty(const char* shorty, bool jni) {
     41   if (shorty[0] == 'F' || shorty[0] == 'D') {
     42     if (jni) {
     43       return X86ManagedRegister::FromX87Register(ST0);
     44     } else {
     45       return X86ManagedRegister::FromXmmRegister(XMM0);
     46     }
     47   } else if (shorty[0] == 'J') {
     48     return X86ManagedRegister::FromRegisterPair(EAX_EDX);
     49   } else if (shorty[0] == 'V') {
     50     return ManagedRegister::NoRegister();
     51   } else {
     52     return X86ManagedRegister::FromCpuRegister(EAX);
     53   }
     54 }
     55 
     56 ManagedRegister X86ManagedRuntimeCallingConvention::ReturnRegister() {
     57   return ReturnRegisterForShorty(GetShorty(), false);
     58 }
     59 
     60 ManagedRegister X86JniCallingConvention::ReturnRegister() {
     61   return ReturnRegisterForShorty(GetShorty(), true);
     62 }
     63 
     64 ManagedRegister X86JniCallingConvention::IntReturnRegister() {
     65   return X86ManagedRegister::FromCpuRegister(EAX);
     66 }
     67 
     68 // Managed runtime calling convention
     69 
     70 ManagedRegister X86ManagedRuntimeCallingConvention::MethodRegister() {
     71   return X86ManagedRegister::FromCpuRegister(EAX);
     72 }
     73 
     74 bool X86ManagedRuntimeCallingConvention::IsCurrentParamInRegister() {
     75   return false;  // Everything is passed by stack
     76 }
     77 
     78 bool X86ManagedRuntimeCallingConvention::IsCurrentParamOnStack() {
     79   return true;  // Everything is passed by stack
     80 }
     81 
     82 ManagedRegister X86ManagedRuntimeCallingConvention::CurrentParamRegister() {
     83   LOG(FATAL) << "Should not reach here";
     84   return ManagedRegister::NoRegister();
     85 }
     86 
     87 FrameOffset X86ManagedRuntimeCallingConvention::CurrentParamStackOffset() {
     88   return FrameOffset(displacement_.Int32Value() +   // displacement
     89                      kFramePointerSize +                 // Method*
     90                      (itr_slots_ * kFramePointerSize));  // offset into in args
     91 }
     92 
     93 const ManagedRegisterEntrySpills& X86ManagedRuntimeCallingConvention::EntrySpills() {
     94   // We spill the argument registers on X86 to free them up for scratch use, we then assume
     95   // all arguments are on the stack.
     96   if (entry_spills_.size() == 0) {
     97     size_t num_spills = NumArgs() + NumLongOrDoubleArgs();
     98     if (num_spills > 0) {
     99       entry_spills_.push_back(X86ManagedRegister::FromCpuRegister(ECX));
    100       if (num_spills > 1) {
    101         entry_spills_.push_back(X86ManagedRegister::FromCpuRegister(EDX));
    102         if (num_spills > 2) {
    103           entry_spills_.push_back(X86ManagedRegister::FromCpuRegister(EBX));
    104         }
    105       }
    106     }
    107   }
    108   return entry_spills_;
    109 }
    110 
    111 // JNI calling convention
    112 
    113 X86JniCallingConvention::X86JniCallingConvention(bool is_static, bool is_synchronized,
    114                                                  const char* shorty)
    115     : JniCallingConvention(is_static, is_synchronized, shorty, kFramePointerSize) {
    116   callee_save_regs_.push_back(X86ManagedRegister::FromCpuRegister(EBP));
    117   callee_save_regs_.push_back(X86ManagedRegister::FromCpuRegister(ESI));
    118   callee_save_regs_.push_back(X86ManagedRegister::FromCpuRegister(EDI));
    119 }
    120 
    121 uint32_t X86JniCallingConvention::CoreSpillMask() const {
    122   return 1 << EBP | 1 << ESI | 1 << EDI | 1 << kNumberOfCpuRegisters;
    123 }
    124 
    125 size_t X86JniCallingConvention::FrameSize() {
    126   // Method*, return address and callee save area size, local reference segment state
    127   size_t frame_data_size = sizeof(StackReference<mirror::ArtMethod>) +
    128       (2 + CalleeSaveRegisters().size()) * kFramePointerSize;
    129   // References plus 2 words for HandleScope header
    130   size_t handle_scope_size = HandleScope::SizeOf(kFramePointerSize, ReferenceCount());
    131   // Plus return value spill area size
    132   return RoundUp(frame_data_size + handle_scope_size + SizeOfReturnValue(), kStackAlignment);
    133 }
    134 
    135 size_t X86JniCallingConvention::OutArgSize() {
    136   return RoundUp(NumberOfOutgoingStackArgs() * kFramePointerSize, kStackAlignment);
    137 }
    138 
    139 bool X86JniCallingConvention::IsCurrentParamInRegister() {
    140   return false;  // Everything is passed by stack.
    141 }
    142 
    143 bool X86JniCallingConvention::IsCurrentParamOnStack() {
    144   return true;  // Everything is passed by stack.
    145 }
    146 
    147 ManagedRegister X86JniCallingConvention::CurrentParamRegister() {
    148   LOG(FATAL) << "Should not reach here";
    149   return ManagedRegister::NoRegister();
    150 }
    151 
    152 FrameOffset X86JniCallingConvention::CurrentParamStackOffset() {
    153   return FrameOffset(displacement_.Int32Value() - OutArgSize() + (itr_slots_ * kFramePointerSize));
    154 }
    155 
    156 size_t X86JniCallingConvention::NumberOfOutgoingStackArgs() {
    157   size_t static_args = IsStatic() ? 1 : 0;  // count jclass
    158   // regular argument parameters and this
    159   size_t param_args = NumArgs() + NumLongOrDoubleArgs();
    160   // count JNIEnv* and return pc (pushed after Method*)
    161   size_t total_args = static_args + param_args + 2;
    162   return total_args;
    163 }
    164 
    165 }  // namespace x86
    166 }  // namespace art
    167