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.

// A light-weight IA32 Assembler.

#ifndef V8_IA32_ASSEMBLER_IA32_INL_H_

#define V8_IA32_ASSEMBLER_IA32_INL_H_

#include "ia32/assembler-ia32.h"

#include "cpu.h"

#include "debug.h"

namespace v8 {

namespace internal {

static const byte kCallOpcode = 0xE8;

static const int kNoCodeAgeSequenceLength = 5;

// The modes possibly affected by apply must be in kApplyMask.

void RelocInfo::apply(intptr_t delta) {

  if (IsRuntimeEntry(rmode_) || IsCodeTarget(rmode_)) {

    int32_t* p = reinterpret_cast<int32_t*>(pc_);

    *p -= delta;  // Relocate entry.

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

  } else if (rmode_ == CODE_AGE_SEQUENCE) {

    if (*pc_ == kCallOpcode) {

      int32_t* p = reinterpret_cast<int32_t*>(pc_ + 1);

      *p -= delta;  // Relocate entry.

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

    }

  } else if (rmode_ == JS_RETURN && IsPatchedReturnSequence()) {

    // Special handling of js_return when a break point is set (call

    // instruction has been inserted).

    int32_t* p = reinterpret_cast<int32_t*>(pc_ + 1);

    *p -= delta;  // Relocate entry.

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

  } else if (rmode_ == DEBUG_BREAK_SLOT && IsPatchedDebugBreakSlotSequence()) {

    // Special handling of a debug break slot when a break point is set (call

    // instruction has been inserted).

    int32_t* p = reinterpret_cast<int32_t*>(pc_ + 1);

    *p -= delta;  // Relocate entry.

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

  } else if (IsInternalReference(rmode_)) {

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

    int32_t* p = reinterpret_cast<int32_t*>(pc_);

    *p += delta;  // Relocate entry.

    CPU::FlushICache(p, 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);

  return reinterpret_cast<Address>(pc_);

}

int RelocInfo::target_address_size() {

  return Assembler::kSpecialTargetSize;

}

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

  Assembler::set_target_address_at(pc_, target);

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

  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));

  }

}

Object* RelocInfo::target_object() {

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

  return Memory::Object_at(pc_);

}

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

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

  return Memory::Object_Handle_at(pc_);

}

Object** RelocInfo::target_object_address() {

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

  return &Memory::Object_at(pc_);

}

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

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

  ASSERT(!target->IsConsString());

  Memory::Object_at(pc_) = target;

  CPU::FlushICache(pc_, sizeof(Address));

  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_ == RelocInfo::EXTERNAL_REFERENCE);

  return reinterpret_cast<Address*>(pc_);

}

Address RelocInfo::target_runtime_entry(Assembler* origin) {

  ASSERT(IsRuntimeEntry(rmode_));

  return reinterpret_cast<Address>(*reinterpret_cast<int32_t*>(pc_));

}

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;

  CPU::FlushICache(pc_, sizeof(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);

  }

}

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

  ASSERT(rmode_ == RelocInfo::CODE_AGE_SEQUENCE);

  ASSERT(*pc_ == kCallOpcode);

  return Memory::Object_Handle_at(pc_ + 1);

}

Code* RelocInfo::code_age_stub() {

  ASSERT(rmode_ == RelocInfo::CODE_AGE_SEQUENCE);

  ASSERT(*pc_ == kCallOpcode);

  return Code::GetCodeFromTargetAddress(

      Assembler::target_address_at(pc_ + 1));

}

void RelocInfo::set_code_age_stub(Code* stub) {

  ASSERT(*pc_ == kCallOpcode);

  ASSERT(rmode_ == RelocInfo::CODE_AGE_SEQUENCE);

  Assembler::set_target_address_at(pc_ + 1, stub->instruction_start());

}

Address RelocInfo::call_address() {

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

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

  return Assembler::target_address_at(pc_ + 1);

}

void RelocInfo::set_call_address(Address target) {

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

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

  Assembler::set_target_address_at(pc_ + 1, 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();

}

void RelocInfo::set_call_object(Object* target) {

  *call_object_address() = target;

}

Object** RelocInfo::call_object_address() {

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

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

  return reinterpret_cast<Object**>(pc_ + 1);

}

bool RelocInfo::IsPatchedReturnSequence() {

  return *pc_ == kCallOpcode;

}

bool RelocInfo::IsPatchedDebugBreakSlotSequence() {

  return !Assembler::IsNop(pc());

}

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

  RelocInfo::Mode mode = rmode();

  if (mode == RelocInfo::EMBEDDED_OBJECT) {

    visitor->VisitEmbeddedPointer(this);

    CPU::FlushICache(pc_, sizeof(Address));

  } 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);

    CPU::FlushICache(pc_, sizeof(Address));

  } 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 (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);

    CPU::FlushICache(pc_, sizeof(Address));

  } 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);

    CPU::FlushICache(pc_, sizeof(Address));

  } 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 (IsRuntimeEntry(mode)) {

    StaticVisitor::VisitRuntimeEntry(this);

  }

}

Immediate::Immediate(int x)  {

  x_ = x;

  rmode_ = RelocInfo::NONE32;

}

Immediate::Immediate(const ExternalReference& ext) {

  x_ = reinterpret_cast<int32_t>(ext.address());

  rmode_ = RelocInfo::EXTERNAL_REFERENCE;

}

Immediate::Immediate(Label* internal_offset) {

  x_ = reinterpret_cast<int32_t>(internal_offset);

  rmode_ = RelocInfo::INTERNAL_REFERENCE;

}

Immediate::Immediate(Handle<Object> handle) {

  AllowDeferredHandleDereference using_raw_address;

  // Verify all Objects referred by code are NOT in new space.

  Object* obj = *handle;

  if (obj->IsHeapObject()) {

    ASSERT(!HeapObject::cast(obj)->GetHeap()->InNewSpace(obj));

    x_ = reinterpret_cast<intptr_t>(handle.location());

    rmode_ = RelocInfo::EMBEDDED_OBJECT;

  } else {

    // no relocation needed

    x_ =  reinterpret_cast<intptr_t>(obj);

    rmode_ = RelocInfo::NONE32;

  }

}

Immediate::Immediate(Smi* value) {

  x_ = reinterpret_cast<intptr_t>(value);

  rmode_ = RelocInfo::NONE32;

}

Immediate::Immediate(Address addr) {

  x_ = reinterpret_cast<int32_t>(addr);

  rmode_ = RelocInfo::NONE32;

}

void Assembler::emit(uint32_t x) {

  *reinterpret_cast<uint32_t*>(pc_) = x;

  pc_ += sizeof(uint32_t);

}

void Assembler::emit(Handle<Object> handle) {

  AllowDeferredHandleDereference heap_object_check;

  // Verify all Objects referred by code are NOT in new space.

  Object* obj = *handle;

  ASSERT(!isolate()->heap()->InNewSpace(obj));

  if (obj->IsHeapObject()) {

    emit(reinterpret_cast<intptr_t>(handle.location()),

         RelocInfo::EMBEDDED_OBJECT);

  } else {

    // no relocation needed

    emit(reinterpret_cast<intptr_t>(obj));

  }

}

void Assembler::emit(uint32_t x, RelocInfo::Mode rmode, TypeFeedbackId id) {

  if (rmode == RelocInfo::CODE_TARGET && !id.IsNone()) {

    RecordRelocInfo(RelocInfo::CODE_TARGET_WITH_ID, id.ToInt());

  } else if (!RelocInfo::IsNone(rmode)

      && rmode != RelocInfo::CODE_AGE_SEQUENCE) {

    RecordRelocInfo(rmode);

  }

  emit(x);

}

void Assembler::emit(Handle<Code> code,

                     RelocInfo::Mode rmode,

                     TypeFeedbackId id) {

  AllowDeferredHandleDereference embedding_raw_address;

  emit(reinterpret_cast<intptr_t>(code.location()), rmode, id);

}

void Assembler::emit(const Immediate& x) {

  if (x.rmode_ == RelocInfo::INTERNAL_REFERENCE) {

    Label* label = reinterpret_cast<Label*>(x.x_);

    emit_code_relative_offset(label);

    return;

  }

  if (!RelocInfo::IsNone(x.rmode_)) RecordRelocInfo(x.rmode_);

  emit(x.x_);

}

void Assembler::emit_code_relative_offset(Label* label) {

  if (label->is_bound()) {

    int32_t pos;

    pos = label->pos() + Code::kHeaderSize - kHeapObjectTag;

    emit(pos);

  } else {

    emit_disp(label, Displacement::CODE_RELATIVE);

  }

}

void Assembler::emit_w(const Immediate& x) {

  ASSERT(RelocInfo::IsNone(x.rmode_));

  uint16_t value = static_cast<uint16_t>(x.x_);

  reinterpret_cast<uint16_t*>(pc_)[0] = value;

  pc_ += sizeof(uint16_t);

}

Address Assembler::target_address_at(Address pc) {

  return pc + sizeof(int32_t) + *reinterpret_cast<int32_t*>(pc);

}

void Assembler::set_target_address_at(Address pc, Address target) {

  int32_t* p = reinterpret_cast<int32_t*>(pc);

  *p = target - (pc + sizeof(int32_t));

  CPU::FlushICache(p, sizeof(int32_t));

}

Address Assembler::target_address_from_return_address(Address pc) {

  return pc - kCallTargetAddressOffset;

}

Displacement Assembler::disp_at(Label* L) {

  return Displacement(long_at(L->pos()));

}

void Assembler::disp_at_put(Label* L, Displacement disp) {

  long_at_put(L->pos(), disp.data());

}

void Assembler::emit_disp(Label* L, Displacement::Type type) {

  Displacement disp(L, type);

  L->link_to(pc_offset());

  emit(static_cast<int>(disp.data()));

}

void Assembler::emit_near_disp(Label* L) {

  byte disp = 0x00;

  if (L->is_near_linked()) {

    int offset = L->near_link_pos() - pc_offset();

    ASSERT(is_int8(offset));

    disp = static_cast<byte>(offset & 0xFF);

  }

  L->link_to(pc_offset(), Label::kNear);

  *pc_++ = disp;

}

void Operand::set_modrm(int mod, Register rm) {

  ASSERT((mod & -4) == 0);

  buf_[0] = mod << 6 | rm.code();

  len_ = 1;

}

void Operand::set_sib(ScaleFactor scale, Register index, Register base) {

  ASSERT(len_ == 1);

  ASSERT((scale & -4) == 0);

  // Use SIB with no index register only for base esp.

  ASSERT(!index.is(esp) || base.is(esp));

  buf_[1] = scale << 6 | index.code() << 3 | base.code();

  len_ = 2;

}

void Operand::set_disp8(int8_t disp) {

  ASSERT(len_ == 1 || len_ == 2);

  *reinterpret_cast<int8_t*>(&buf_[len_++]) = disp;

}

void Operand::set_dispr(int32_t disp, RelocInfo::Mode rmode) {

  ASSERT(len_ == 1 || len_ == 2);

  int32_t* p = reinterpret_cast<int32_t*>(&buf_[len_]);

  *p = disp;

  len_ += sizeof(int32_t);

  rmode_ = rmode;

}

Operand::Operand(Register reg) {

  // reg

  set_modrm(3, reg);

}

Operand::Operand(XMMRegister xmm_reg) {

  Register reg = { xmm_reg.code() };

  set_modrm(3, reg);

}

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

  // [disp/r]

  set_modrm(0, ebp);

  set_dispr(disp, rmode);

}

} }  // namespace v8::internal

#endif  // V8_IA32_ASSEMBLER_IA32_INL_H_