CSE2410 Fall 2014 Bounce

// Copyright (c) 1994-2006 Sun Microsystems Inc.

// All Rights Reserved.

//

// Redistribution and use in source and binary forms, with or without

// modification, are permitted provided that the following conditions are

// met:

//

// - Redistributions of source code must retain the above copyright notice,

// this list of conditions and the following disclaimer.

//

// - Redistribution in binary form must reproduce the above copyright

// notice, this list of conditions and the following disclaimer in the

// documentation and/or other materials provided with the distribution.

//

// - Neither the name of Sun Microsystems or the names of contributors may

// be used to endorse or promote products derived from this software without

// specific prior written permission.

//

// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS

// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,

// THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR

// PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR

// CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,

// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,

// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// The original source code covered by the above license above has been

// modified significantly by Google Inc.

// Copyright 2012 the V8 project authors. All rights reserved.

#ifndef V8_MIPS_ASSEMBLER_MIPS_INL_H_

#define V8_MIPS_ASSEMBLER_MIPS_INL_H_

#include "mips/assembler-mips.h"

#include "cpu.h"

#include "debug.h"

namespace v8 {

namespace internal {

// -----------------------------------------------------------------------------

// Operand and MemOperand.

Operand::Operand(int32_t immediate, RelocInfo::Mode rmode)  {

  rm_ = no_reg;

  imm32_ = immediate;

  rmode_ = rmode;

}

Operand::Operand(const ExternalReference& f)  {

  rm_ = no_reg;

  imm32_ = reinterpret_cast<int32_t>(f.address());

  rmode_ = RelocInfo::EXTERNAL_REFERENCE;

}

Operand::Operand(Smi* value) {

  rm_ = no_reg;

  imm32_ =  reinterpret_cast<intptr_t>(value);

  rmode_ = RelocInfo::NONE32;

}

Operand::Operand(Register rm) {

  rm_ = rm;

}

bool Operand::is_reg() const {

  return rm_.is_valid();

}

int Register::NumAllocatableRegisters() {

    return kMaxNumAllocatableRegisters;

}

int DoubleRegister::NumRegisters() {

    return FPURegister::kMaxNumRegisters;

}

int DoubleRegister::NumAllocatableRegisters() {

    return FPURegister::kMaxNumAllocatableRegisters;

}

int FPURegister::ToAllocationIndex(FPURegister reg) {

  ASSERT(reg.code() % 2 == 0);

  ASSERT(reg.code() / 2 < kMaxNumAllocatableRegisters);

  ASSERT(reg.is_valid());

  ASSERT(!reg.is(kDoubleRegZero));

  ASSERT(!reg.is(kLithiumScratchDouble));

  return (reg.code() / 2);

}

// -----------------------------------------------------------------------------

// RelocInfo.

void RelocInfo::apply(intptr_t delta) {

  if (IsCodeTarget(rmode_)) {

    uint32_t scope1 = (uint32_t) target_address() & ~kImm28Mask;

    uint32_t scope2 = reinterpret_cast<uint32_t>(pc_) & ~kImm28Mask;

    if (scope1 != scope2) {

      Assembler::JumpLabelToJumpRegister(pc_);

    }

  }

  if (IsInternalReference(rmode_)) {

    // Absolute code pointer inside code object moves with the code object.

    byte* p = reinterpret_cast<byte*>(pc_);

    int count = Assembler::RelocateInternalReference(p, delta);

    CPU::FlushICache(p, count * sizeof(uint32_t));

  }

}

Address RelocInfo::target_address() {

  ASSERT(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_));

  return Assembler::target_address_at(pc_);

}

Address RelocInfo::target_address_address() {

  ASSERT(IsCodeTarget(rmode_) ||

         IsRuntimeEntry(rmode_) ||

         rmode_ == EMBEDDED_OBJECT ||

         rmode_ == EXTERNAL_REFERENCE);

  // Read the address of the word containing the target_address in an

  // instruction stream.

  // The only architecture-independent user of this function is the serializer.

  // The serializer uses it to find out how many raw bytes of instruction to

  // output before the next target.

  // For an instruction like LUI/ORI where the target bits are mixed into the

  // instruction bits, the size of the target will be zero, indicating that the

  // serializer should not step forward in memory after a target is resolved

  // and written. In this case the target_address_address function should

  // return the end of the instructions to be patched, allowing the

  // deserializer to deserialize the instructions as raw bytes and put them in

  // place, ready to be patched with the target. After jump optimization,

  // that is the address of the instruction that follows J/JAL/JR/JALR

  // instruction.

  return reinterpret_cast<Address>(

    pc_ + Assembler::kInstructionsFor32BitConstant * Assembler::kInstrSize);

}

int RelocInfo::target_address_size() {

  return Assembler::kSpecialTargetSize;

}

void RelocInfo::set_target_address(Address target, WriteBarrierMode mode) {

  ASSERT(IsCodeTarget(rmode_) || IsRuntimeEntry(rmode_));

  Assembler::set_target_address_at(pc_, target);

  if (mode == UPDATE_WRITE_BARRIER && host() != NULL && IsCodeTarget(rmode_)) {

    Object* target_code = Code::GetCodeFromTargetAddress(target);

    host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(

        host(), this, HeapObject::cast(target_code));

  }

}

Address Assembler::target_address_from_return_address(Address pc) {

  return pc - kCallTargetAddressOffset;

}

Object* RelocInfo::target_object() {

  ASSERT(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);

  return reinterpret_cast<Object*>(Assembler::target_address_at(pc_));

}

Handle<Object> RelocInfo::target_object_handle(Assembler* origin) {

  ASSERT(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);

  return Handle<Object>(reinterpret_cast<Object**>(

      Assembler::target_address_at(pc_)));

}

Object** RelocInfo::target_object_address() {

  // Provide a "natural pointer" to the embedded object,

  // which can be de-referenced during heap iteration.

  ASSERT(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);

  reconstructed_obj_ptr_ =

      reinterpret_cast<Object*>(Assembler::target_address_at(pc_));

  return &reconstructed_obj_ptr_;

}

void RelocInfo::set_target_object(Object* target, WriteBarrierMode mode) {

  ASSERT(IsCodeTarget(rmode_) || rmode_ == EMBEDDED_OBJECT);

  ASSERT(!target->IsConsString());

  Assembler::set_target_address_at(pc_, reinterpret_cast<Address>(target));

  if (mode == UPDATE_WRITE_BARRIER &&

      host() != NULL &&

      target->IsHeapObject()) {

    host()->GetHeap()->incremental_marking()->RecordWrite(

        host(), &Memory::Object_at(pc_), HeapObject::cast(target));

  }

}

Address* RelocInfo::target_reference_address() {

  ASSERT(rmode_ == EXTERNAL_REFERENCE);

  reconstructed_adr_ptr_ = Assembler::target_address_at(pc_);

  return &reconstructed_adr_ptr_;

}

Address RelocInfo::target_runtime_entry(Assembler* origin) {

  ASSERT(IsRuntimeEntry(rmode_));

  return target_address();

}

void RelocInfo::set_target_runtime_entry(Address target,

                                         WriteBarrierMode mode) {

  ASSERT(IsRuntimeEntry(rmode_));

  if (target_address() != target) set_target_address(target, mode);

}

Handle<Cell> RelocInfo::target_cell_handle() {

  ASSERT(rmode_ == RelocInfo::CELL);

  Address address = Memory::Address_at(pc_);

  return Handle<Cell>(reinterpret_cast<Cell**>(address));

}

Cell* RelocInfo::target_cell() {

  ASSERT(rmode_ == RelocInfo::CELL);

  return Cell::FromValueAddress(Memory::Address_at(pc_));

}

void RelocInfo::set_target_cell(Cell* cell, WriteBarrierMode mode) {

  ASSERT(rmode_ == RelocInfo::CELL);

  Address address = cell->address() + Cell::kValueOffset;

  Memory::Address_at(pc_) = address;

  if (mode == UPDATE_WRITE_BARRIER && host() != NULL) {

    // TODO(1550) We are passing NULL as a slot because cell can never be on

    // evacuation candidate.

    host()->GetHeap()->incremental_marking()->RecordWrite(

        host(), NULL, cell);

  }

}

static const int kNoCodeAgeSequenceLength = 7;

Handle<Object> RelocInfo::code_age_stub_handle(Assembler* origin) {

  UNREACHABLE();  // This should never be reached on Arm.

  return Handle<Object>();

}

Code* RelocInfo::code_age_stub() {

  ASSERT(rmode_ == RelocInfo::CODE_AGE_SEQUENCE);

  return Code::GetCodeFromTargetAddress(

      Memory::Address_at(pc_ + Assembler::kInstrSize *

                         (kNoCodeAgeSequenceLength - 1)));

}

void RelocInfo::set_code_age_stub(Code* stub) {

  ASSERT(rmode_ == RelocInfo::CODE_AGE_SEQUENCE);

  Memory::Address_at(pc_ + Assembler::kInstrSize *

                     (kNoCodeAgeSequenceLength - 1)) =

      stub->instruction_start();

}

Address RelocInfo::call_address() {

  ASSERT((IsJSReturn(rmode()) && IsPatchedReturnSequence()) ||

         (IsDebugBreakSlot(rmode()) && IsPatchedDebugBreakSlotSequence()));

  // The pc_ offset of 0 assumes mips patched return sequence per

  // debug-mips.cc BreakLocationIterator::SetDebugBreakAtReturn(), or

  // debug break slot per BreakLocationIterator::SetDebugBreakAtSlot().

  return Assembler::target_address_at(pc_);

}

void RelocInfo::set_call_address(Address target) {

  ASSERT((IsJSReturn(rmode()) && IsPatchedReturnSequence()) ||

         (IsDebugBreakSlot(rmode()) && IsPatchedDebugBreakSlotSequence()));

  // The pc_ offset of 0 assumes mips patched return sequence per

  // debug-mips.cc BreakLocationIterator::SetDebugBreakAtReturn(), or

  // debug break slot per BreakLocationIterator::SetDebugBreakAtSlot().

  Assembler::set_target_address_at(pc_, target);

  if (host() != NULL) {

    Object* target_code = Code::GetCodeFromTargetAddress(target);

    host()->GetHeap()->incremental_marking()->RecordWriteIntoCode(

        host(), this, HeapObject::cast(target_code));

  }

}

Object* RelocInfo::call_object() {

  return *call_object_address();

}

Object** RelocInfo::call_object_address() {

  ASSERT((IsJSReturn(rmode()) && IsPatchedReturnSequence()) ||

         (IsDebugBreakSlot(rmode()) && IsPatchedDebugBreakSlotSequence()));

  return reinterpret_cast<Object**>(pc_ + 2 * Assembler::kInstrSize);

}

void RelocInfo::set_call_object(Object* target) {

  *call_object_address() = target;

}

bool RelocInfo::IsPatchedReturnSequence() {

  Instr instr0 = Assembler::instr_at(pc_);

  Instr instr1 = Assembler::instr_at(pc_ + 1 * Assembler::kInstrSize);

  Instr instr2 = Assembler::instr_at(pc_ + 2 * Assembler::kInstrSize);

  bool patched_return = ((instr0 & kOpcodeMask) == LUI &&

                         (instr1 & kOpcodeMask) == ORI &&

                         ((instr2 & kOpcodeMask) == JAL ||

                          ((instr2 & kOpcodeMask) == SPECIAL &&

                           (instr2 & kFunctionFieldMask) == JALR)));

  return patched_return;

}

bool RelocInfo::IsPatchedDebugBreakSlotSequence() {

  Instr current_instr = Assembler::instr_at(pc_);

  return !Assembler::IsNop(current_instr, Assembler::DEBUG_BREAK_NOP);

}

void RelocInfo::Visit(Isolate* isolate, ObjectVisitor* visitor) {

  RelocInfo::Mode mode = rmode();

  if (mode == RelocInfo::EMBEDDED_OBJECT) {

    visitor->VisitEmbeddedPointer(this);

  } else if (RelocInfo::IsCodeTarget(mode)) {

    visitor->VisitCodeTarget(this);

  } else if (mode == RelocInfo::CELL) {

    visitor->VisitCell(this);

  } else if (mode == RelocInfo::EXTERNAL_REFERENCE) {

    visitor->VisitExternalReference(this);

  } else if (RelocInfo::IsCodeAgeSequence(mode)) {

    visitor->VisitCodeAgeSequence(this);

#ifdef ENABLE_DEBUGGER_SUPPORT

  } else if (((RelocInfo::IsJSReturn(mode) &&

              IsPatchedReturnSequence()) ||

             (RelocInfo::IsDebugBreakSlot(mode) &&

             IsPatchedDebugBreakSlotSequence())) &&

             isolate->debug()->has_break_points()) {

    visitor->VisitDebugTarget(this);

#endif

  } else if (RelocInfo::IsRuntimeEntry(mode)) {

    visitor->VisitRuntimeEntry(this);

  }

}

template<typename StaticVisitor>

void RelocInfo::Visit(Heap* heap) {

  RelocInfo::Mode mode = rmode();

  if (mode == RelocInfo::EMBEDDED_OBJECT) {

    StaticVisitor::VisitEmbeddedPointer(heap, this);

  } else if (RelocInfo::IsCodeTarget(mode)) {

    StaticVisitor::VisitCodeTarget(heap, this);

  } else if (mode == RelocInfo::CELL) {

    StaticVisitor::VisitCell(heap, this);

  } else if (mode == RelocInfo::EXTERNAL_REFERENCE) {

    StaticVisitor::VisitExternalReference(this);

  } else if (RelocInfo::IsCodeAgeSequence(mode)) {

    StaticVisitor::VisitCodeAgeSequence(heap, this);

#ifdef ENABLE_DEBUGGER_SUPPORT

  } else if (heap->isolate()->debug()->has_break_points() &&

             ((RelocInfo::IsJSReturn(mode) &&

              IsPatchedReturnSequence()) ||

             (RelocInfo::IsDebugBreakSlot(mode) &&

              IsPatchedDebugBreakSlotSequence()))) {

    StaticVisitor::VisitDebugTarget(heap, this);

#endif

  } else if (RelocInfo::IsRuntimeEntry(mode)) {

    StaticVisitor::VisitRuntimeEntry(this);

  }

}

// -----------------------------------------------------------------------------

// Assembler.

void Assembler::CheckBuffer() {

  if (buffer_space() <= kGap) {

    GrowBuffer();

  }

}

void Assembler::CheckTrampolinePoolQuick() {

  if (pc_offset() >= next_buffer_check_) {

    CheckTrampolinePool();

  }

}

void Assembler::emit(Instr x) {

  if (!is_buffer_growth_blocked()) {

    CheckBuffer();

  }

  *reinterpret_cast<Instr*>(pc_) = x;

  pc_ += kInstrSize;

  CheckTrampolinePoolQuick();

}

} }  // namespace v8::internal

#endif  // V8_MIPS_ASSEMBLER_MIPS_INL_H_