Revert of Reland Implement .eh_frame writer and disassembler.

src/eh-frame.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/eh-frame.h"
-
-#include <iomanip>
-#include <ostream>
-
-#if !defined(V8_TARGET_ARCH_X64) && !defined(V8_TARGET_ARCH_ARM) && \
-    !defined(V8_TARGET_ARCH_ARM64)
-
-// Placeholders for unsupported architectures.
+#include "src/objects-inl.h"
+#include "src/objects.h"
 
 namespace v8 {
 namespace internal {
 
-STATIC_CONST_MEMBER_DEFINITION const int
-    EhFrameConstants::kCodeAlignmentFactor = 1;
+static const int DW_EH_PE_pcrel = 0x10;
+static const int DW_EH_PE_datarel = 0x30;
+static const int DW_EH_PE_udata4 = 0x03;
+static const int DW_EH_PE_sdata4 = 0x0b;
 
-STATIC_CONST_MEMBER_DEFINITION const int
-    EhFrameConstants::kDataAlignmentFactor = 1;
+const int EhFrameHdr::kCIESize = 0;
 
-void EhFrameWriter::WriteReturnAddressRegisterCode() { UNIMPLEMENTED(); }
+static const int kVersionSize = 1;
+static const int kEncodingSpecifiersSize = 3;
 
-void EhFrameWriter::WriteInitialStateInCie() { UNIMPLEMENTED(); }
+//
+// In order to calculate offsets in the .eh_frame_hdr, we must know the layout
+// of the DSO generated by perf inject, which is assumed to be the following:
+//
+//  |      ...      |                        |
+//  +---------------+ <-- (F) ---            |  Larger offsets in file
+//  |               |           ^            |
+//  |  Instructions |           | .text      v
+//  |               |           v
+//  +---------------+ <-- (E) ---
+//  |///////////////|
+//  |////Padding////|
+//  |///////////////|
+//  +---------------+ <-- (D) ---
+//  |               |           ^
+//  |      CIE      |           |
+//  |               |           |
+//  +---------------+ <-- (C)   | .eh_frame
+//  |               |           |
+//  |      FDE      |           |
+//  |               |           v
+//  +---------------+ <-- (B) ---
+//  |    version    |           ^
+//  +---------------+           |
+//  |   encoding    |           |
+//  |  specifiers   |           |
+//  +---------------+ <---(A)   | .eh_frame_hdr
+//  |   offset to   |           |
+//  |   .eh_frame   |           |
+//  +---------------+           |
+//  |      ...      |          ...
+//
+// (F) is aligned at a 16-byte boundary.
+// (D) is aligned at a  8-byte boundary.
+// (B) is aligned at a  4-byte boundary.
+// (E), (C) and (A) have no alignment requirements.
+//
+// The distance between (A) and (B) is 4 bytes.
+//
+// The size of the .eh_frame is required to be a multiple of the pointer size,
+// which means that (B) will be naturally aligned to a 4-byte boundary on all
+// the architectures we support.
+//
+// Because (E) has no alignment requirements, there is padding between (E) and
+// (D). (F) is aligned at a 16-byte boundary, thus to a 8-byte one as well.
+//
+EhFrameHdr::EhFrameHdr(Code* code) {
+  int code_size = code->is_crankshafted() ? code->safepoint_table_offset()
+                                          : code->instruction_size();
+  version_ = 1;
+  eh_frame_ptr_encoding_ = DW_EH_PE_sdata4 | DW_EH_PE_pcrel;
+  lut_size_encoding_ = DW_EH_PE_udata4;
+  lut_entries_encoding_ = DW_EH_PE_sdata4 | DW_EH_PE_datarel;
 
-int EhFrameWriter::RegisterToDwarfCode(Register) {
-  UNIMPLEMENTED();
-  return -1;
+  // .eh_frame pointer and LUT
+  if (code->has_unwinding_info()) {
+    DCHECK_GE(code->unwinding_info_size(), EhFrameHdr::kRecordSize);
+    int eh_frame_size = code->unwinding_info_size() - EhFrameHdr::kRecordSize;
+
+    offset_to_eh_frame_ =
+        -(eh_frame_size + kVersionSize + kEncodingSpecifiersSize);  // A -> D
+    lut_entries_number_ = 1;
+    offset_to_procedure_ = -(RoundUp(code_size, 8) + eh_frame_size);  // B -> F
+    offset_to_fde_ = -(eh_frame_size - kCIESize);                     // B -> C
+  } else {
+    // Create a dummy table
+    offset_to_eh_frame_ = 0;
+    lut_entries_number_ = 0;
+    offset_to_procedure_ = 0;
+    offset_to_fde_ = 0;
+  }
 }
 
-#ifdef ENABLE_DISASSEMBLER
-
-const char* EhFrameDisassembler::DwarfRegisterCodeToString(int) {
-  UNIMPLEMENTED();
-  return nullptr;
-}
-
-#endif
-
 }  // namespace internal
 }  // namespace v8
-
-#endif
-
-namespace v8 {
-namespace internal {
-
-STATIC_CONST_MEMBER_DEFINITION const int
-    EhFrameConstants::kEhFrameTerminatorSize;
-STATIC_CONST_MEMBER_DEFINITION const int EhFrameConstants::kEhFrameHdrVersion;
-STATIC_CONST_MEMBER_DEFINITION const int EhFrameConstants::kEhFrameHdrSize;
-
-STATIC_CONST_MEMBER_DEFINITION const uint32_t EhFrameWriter::kInt32Placeholder;
-
-// static
-void EhFrameWriter::WriteEmptyEhFrame(std::ostream& stream) {  // NOLINT
-  stream.put(EhFrameConstants::kEhFrameHdrVersion);
-
-  // .eh_frame pointer encoding specifier.
-  stream.put(EhFrameConstants::kSData4 | EhFrameConstants::kPcRel);
-
-  // Lookup table size encoding.
-  stream.put(EhFrameConstants::kUData4);
-
-  // Lookup table entries encoding.
-  stream.put(EhFrameConstants::kSData4 | EhFrameConstants::kDataRel);
-
-  // Dummy pointers and 0 entries in the lookup table.
-  char dummy_data[EhFrameConstants::kEhFrameHdrSize - 4] = {0};
-  stream.write(&dummy_data[0], sizeof(dummy_data));
-}
-
-EhFrameWriter::EhFrameWriter(Zone* zone)
-    : cie_size_(0),
-      last_pc_offset_(0),
-      writer_state_(InternalState::kUndefined),
-      base_register_(no_reg),
-      base_offset_(0),
-      eh_frame_buffer_(zone) {}
-
-void EhFrameWriter::Initialize() {
-  DCHECK(writer_state_ == InternalState::kUndefined);
-  eh_frame_buffer_.reserve(128);
-  writer_state_ = InternalState::kInitialized;
-  WriteCie();
-  WriteFdeHeader();
-}
-
-void EhFrameWriter::WriteCie() {
-  static const int kCIEIdentifier = 0;
-  static const int kCIEVersion = 3;
-  static const int kAugmentationDataSize = 2;
-  static const byte kAugmentationString[] = {'z', 'L', 'R', 0};
-
-  // Placeholder for the size of the CIE.
-  int size_offset = eh_frame_offset();
-  WriteInt32(kInt32Placeholder);
-
-  // CIE identifier and version.
-  int record_start_offset = eh_frame_offset();
-  WriteInt32(kCIEIdentifier);
-  WriteByte(kCIEVersion);
-
-  // Augmentation data contents descriptor: LSDA and FDE encoding.
-  WriteBytes(&kAugmentationString[0], sizeof(kAugmentationString));
-
-  // Alignment factors.
-  WriteSLeb128(EhFrameConstants::kCodeAlignmentFactor);
-  WriteSLeb128(EhFrameConstants::kDataAlignmentFactor);
-
-  WriteReturnAddressRegisterCode();
-
-  // Augmentation data.
-  WriteULeb128(kAugmentationDataSize);
-  // No language-specific data area (LSDA).
-  WriteByte(EhFrameConstants::kOmit);
-  // FDE pointers encoding.
-  WriteByte(EhFrameConstants::kSData4 | EhFrameConstants::kPcRel);
-
-  // Write directives to build the initial state of the unwinding table.
-  DCHECK_EQ(eh_frame_offset() - size_offset,
-            EhFrameConstants::kInitialStateOffsetInCie);
-  WriteInitialStateInCie();
-
-  // Pad with nops to the next multiple of 8 bytes.
-  WritePaddingTo8ByteAlignment();
-
-  int record_end_offset = eh_frame_offset();
-  int encoded_cie_size = record_end_offset - record_start_offset;
-  cie_size_ = record_end_offset - size_offset;
-
-  // Patch the size of the CIE now that we know it.
-  PatchInt32(size_offset, encoded_cie_size);
-}
-
-void EhFrameWriter::WriteFdeHeader() {
-  DCHECK_NE(cie_size_, 0);
-
-  // Placeholder for size of the FDE. Will be filled in Finish().
-  DCHECK_EQ(eh_frame_offset(), fde_offset());
-  WriteInt32(kInt32Placeholder);
-
-  // Backwards offset to the CIE.
-  WriteInt32(cie_size_ + kInt32Size);
-
-  // Placeholder for pointer to procedure. Will be filled in Finish().
-  DCHECK_EQ(eh_frame_offset(), GetProcedureAddressOffset());
-  WriteInt32(kInt32Placeholder);
-
-  // Placeholder for size of the procedure. Will be filled in Finish().
-  DCHECK_EQ(eh_frame_offset(), GetProcedureSizeOffset());
-  WriteInt32(kInt32Placeholder);
-
-  // No augmentation data.
-  WriteByte(0);
-}
-
-void EhFrameWriter::WriteEhFrameHdr(int code_size) {
-  DCHECK(writer_state_ == InternalState::kInitialized);
-
-  //
-  // In order to calculate offsets in the .eh_frame_hdr, we must know the layout
-  // of the DSO generated by perf inject, which is assumed to be the following:
-  //
-  //  |      ...      |                        |
-  //  +---------------+ <-- (F) ---            |  Larger offsets in file
-  //  |               |           ^            |
-  //  |  Instructions |           | .text      v
-  //  |               |           v
-  //  +---------------+ <-- (E) ---
-  //  |///////////////|
-  //  |////Padding////|
-  //  |///////////////|
-  //  +---------------+ <-- (D) ---
-  //  |               |           ^
-  //  |      CIE      |           |
-  //  |               |           |
-  //  +---------------+ <-- (C)   |
-  //  |               |           | .eh_frame
-  //  |      FDE      |           |
-  //  |               |           |
-  //  +---------------+           |
-  //  |   terminator  |           v
-  //  +---------------+ <-- (B) ---
-  //  |    version    |           ^
-  //  +---------------+           |
-  //  |   encoding    |           |
-  //  |  specifiers   |           |
-  //  +---------------+ <---(A)   | .eh_frame_hdr
-  //  |   offset to   |           |
-  //  |   .eh_frame   |           |
-  //  +---------------+           |
-  //  |      ...      |          ...
-  //
-  // (F) is aligned to a 16-byte boundary.
-  // (D) is aligned to a  8-byte boundary.
-  // (B) is aligned to a  4-byte boundary.
-  // (C) is aligned to an addressing unit size boundary.
-  // (E) and (A) have no alignment requirements.
-  //
-  // The distance between (A) and (B) is 4 bytes.
-  //
-  // The size of the FDE is required to be a multiple of the pointer size, which
-  // means that (B) will be naturally aligned to a 4-byte boundary on all the
-  // architectures we support.
-  //
-  // Because (E) has no alignment requirements, there is padding between (E) and
-  // (D). (F) is aligned at a 16-byte boundary, thus to a 8-byte one as well.
-  //
-
-  int eh_frame_size = eh_frame_offset();
-
-  WriteByte(EhFrameConstants::kEhFrameHdrVersion);
-
-  // .eh_frame pointer encoding specifier.
-  WriteByte(EhFrameConstants::kSData4 | EhFrameConstants::kPcRel);
-  // Lookup table size encoding specifier.
-  WriteByte(EhFrameConstants::kUData4);
-  // Lookup table entries encoding specifier.
-  WriteByte(EhFrameConstants::kSData4 | EhFrameConstants::kDataRel);
-
-  // Pointer to .eh_frame, relative to this offset (A -> D in the diagram).
-  WriteInt32(-(eh_frame_size + EhFrameConstants::kFdeVersionSize +
-               EhFrameConstants::kFdeEncodingSpecifiersSize));
-
-  // Number of entries in the LUT, one for the only routine.
-  WriteInt32(1);
-
-  // Pointer to the start of the routine, relative to the beginning of the
-  // .eh_frame_hdr (B -> F in the diagram).
-  WriteInt32(-(RoundUp(code_size, 8) + eh_frame_size));
-
-  // Pointer to the start of the associated FDE, relative to the start of the
-  // .eh_frame_hdr (B -> C  in the diagram).
-  WriteInt32(-(eh_frame_size - cie_size_));
-
-  DCHECK_EQ(eh_frame_offset() - eh_frame_size,
-            EhFrameConstants::kEhFrameHdrSize);
-}
-
-void EhFrameWriter::WritePaddingTo8ByteAlignment() {
-  DCHECK(writer_state_ == InternalState::kInitialized);
-
-  int unpadded_size = eh_frame_offset();
-  int padded_size = RoundUp(unpadded_size, 8);
-  int padding_size = padded_size - unpadded_size;
-
-  byte nop = static_cast<byte>(EhFrameConstants::DwarfOpcodes::kNop);
-  static const byte kPadding[] = {nop, nop, nop, nop, nop, nop, nop, nop};
-  DCHECK_LE(padding_size, static_cast<int>(sizeof(kPadding)));
-  WriteBytes(&kPadding[0], padding_size);
-}
-
-void EhFrameWriter::AdvanceLocation(int pc_offset) {
-  DCHECK(writer_state_ == InternalState::kInitialized);
-  DCHECK_GE(pc_offset, last_pc_offset_);
-  uint32_t delta = pc_offset - last_pc_offset_;
-
-  DCHECK_EQ(delta % EhFrameConstants::kCodeAlignmentFactor, 0);
-  uint32_t factored_delta = delta / EhFrameConstants::kCodeAlignmentFactor;
-
-  if (factored_delta <= EhFrameConstants::kLocationMask) {
-    WriteByte((EhFrameConstants::kLocationTag
-               << EhFrameConstants::kLocationMaskSize) |
-              (factored_delta & EhFrameConstants::kLocationMask));
-  } else if (factored_delta <= kMaxUInt8) {
-    WriteOpcode(EhFrameConstants::DwarfOpcodes::kAdvanceLoc1);
-    WriteByte(factored_delta);
-  } else if (factored_delta <= kMaxUInt16) {
-    WriteOpcode(EhFrameConstants::DwarfOpcodes::kAdvanceLoc2);
-    WriteInt16(factored_delta);
-  } else {
-    WriteOpcode(EhFrameConstants::DwarfOpcodes::kAdvanceLoc4);
-    WriteInt32(factored_delta);
-  }
-
-  last_pc_offset_ = pc_offset;
-}
-
-void EhFrameWriter::SetBaseAddressOffset(int base_offset) {
-  DCHECK(writer_state_ == InternalState::kInitialized);
-  DCHECK_GE(base_offset, 0);
-  WriteOpcode(EhFrameConstants::DwarfOpcodes::kDefCfaOffset);
-  WriteULeb128(base_offset);
-  base_offset_ = base_offset;
-}
-
-void EhFrameWriter::SetBaseAddressRegister(Register base_register) {
-  DCHECK(writer_state_ == InternalState::kInitialized);
-  int code = RegisterToDwarfCode(base_register);
-  WriteOpcode(EhFrameConstants::DwarfOpcodes::kDefCfaRegister);
-  WriteULeb128(code);
-  base_register_ = base_register;
-}
-
-void EhFrameWriter::SetBaseAddressRegisterAndOffset(Register base_register,
-                                                    int base_offset) {
-  DCHECK(writer_state_ == InternalState::kInitialized);
-  DCHECK_GE(base_offset, 0);
-  int code = RegisterToDwarfCode(base_register);
-  WriteOpcode(EhFrameConstants::DwarfOpcodes::kDefCfa);
-  WriteULeb128(code);
-  WriteULeb128(base_offset);
-  base_offset_ = base_offset;
-  base_register_ = base_register;
-}
-
-void EhFrameWriter::RecordRegisterSavedToStack(int register_code, int offset) {
-  DCHECK(writer_state_ == InternalState::kInitialized);
-  DCHECK_EQ(offset % EhFrameConstants::kDataAlignmentFactor, 0);
-  int factored_offset = offset / EhFrameConstants::kDataAlignmentFactor;
-  if (factored_offset >= 0) {
-    DCHECK_LE(register_code, EhFrameConstants::kSavedRegisterMask);
-    WriteByte((EhFrameConstants::kSavedRegisterTag
-               << EhFrameConstants::kSavedRegisterMaskSize) |
-              (register_code & EhFrameConstants::kSavedRegisterMask));
-    WriteULeb128(factored_offset);
-  } else {
-    WriteOpcode(EhFrameConstants::DwarfOpcodes::kOffsetExtendedSf);
-    WriteULeb128(register_code);
-    WriteSLeb128(factored_offset);
-  }
-}
-
-void EhFrameWriter::RecordRegisterNotModified(Register name) {
-  DCHECK(writer_state_ == InternalState::kInitialized);
-  WriteOpcode(EhFrameConstants::DwarfOpcodes::kSameValue);
-  WriteULeb128(RegisterToDwarfCode(name));
-}
-
-void EhFrameWriter::RecordRegisterFollowsInitialRule(Register name) {
-  DCHECK(writer_state_ == InternalState::kInitialized);
-  int code = RegisterToDwarfCode(name);
-  DCHECK_LE(code, EhFrameConstants::kFollowInitialRuleMask);
-  WriteByte((EhFrameConstants::kFollowInitialRuleTag
-             << EhFrameConstants::kFollowInitialRuleMaskSize) |
-            (code & EhFrameConstants::kFollowInitialRuleMask));
-}
-
-void EhFrameWriter::Finish(int code_size) {
-  DCHECK(writer_state_ == InternalState::kInitialized);
-  DCHECK_GE(eh_frame_offset(), cie_size_);
-
-  WritePaddingTo8ByteAlignment();
-
-  // Write the size of the FDE now that we know it.
-  // The encoded size does not include the size field itself.
-  int encoded_fde_size = eh_frame_offset() - fde_offset() - kInt32Size;
-  PatchInt32(fde_offset(), encoded_fde_size);
-
-  // Write size and offset to procedure.
-  PatchInt32(GetProcedureAddressOffset(),
-             -(RoundUp(code_size, 8) + GetProcedureAddressOffset()));
-  PatchInt32(GetProcedureSizeOffset(), code_size);
-
-  // Terminate the .eh_frame.
-  static const byte kTerminator[EhFrameConstants::kEhFrameTerminatorSize] = {0};
-  WriteBytes(&kTerminator[0], EhFrameConstants::kEhFrameTerminatorSize);
-
-  WriteEhFrameHdr(code_size);
-
-  writer_state_ = InternalState::kFinalized;
-}
-
-void EhFrameWriter::GetEhFrame(CodeDesc* desc) {
-  DCHECK(writer_state_ == InternalState::kFinalized);
-  desc->unwinding_info_size = static_cast<int>(eh_frame_buffer_.size());
-  desc->unwinding_info = eh_frame_buffer_.data();
-}
-
-void EhFrameWriter::WriteULeb128(uint32_t value) {
-  do {
-    byte chunk = value & 0x7f;
-    value >>= 7;
-    if (value != 0) chunk |= 0x80;
-    WriteByte(chunk);
-  } while (value != 0);
-}
-
-void EhFrameWriter::WriteSLeb128(int32_t value) {
-  static const int kSignBitMask = 0x40;
-  bool done;
-  do {
-    byte chunk = value & 0x7f;
-    value >>= 7;
-    done = ((value == 0) && ((chunk & kSignBitMask) == 0)) ||
-           ((value == -1) && ((chunk & kSignBitMask) != 0));
-    if (!done) chunk |= 0x80;
-    WriteByte(chunk);
-  } while (!done);
-}
-
-uint32_t EhFrameIterator::GetNextULeb128() {
-  int size = 0;
-  uint32_t result = DecodeULeb128(next_, &size);
-  DCHECK_LE(next_ + size, end_);
-  next_ += size;
-  return result;
-}
-
-int32_t EhFrameIterator::GetNextSLeb128() {
-  int size = 0;
-  int32_t result = DecodeSLeb128(next_, &size);
-  DCHECK_LE(next_ + size, end_);
-  next_ += size;
-  return result;
-}
-
-// static
-uint32_t EhFrameIterator::DecodeULeb128(const byte* encoded,
-                                        int* encoded_size) {
-  const byte* current = encoded;
-  uint32_t result = 0;
-  int shift = 0;
-
-  do {
-    DCHECK_LT(shift, 8 * static_cast<int>(sizeof(result)));
-    result |= (*current & 0x7f) << shift;
-    shift += 7;
-  } while (*current++ >= 128);
-
-  DCHECK_NOT_NULL(encoded_size);
-  *encoded_size = static_cast<int>(current - encoded);
-
-  return result;
-}
-
-// static
-int32_t EhFrameIterator::DecodeSLeb128(const byte* encoded, int* encoded_size) {
-  static const byte kSignBitMask = 0x40;
-
-  const byte* current = encoded;
-  int32_t result = 0;
-  int shift = 0;
-  byte chunk;
-
-  do {
-    chunk = *current++;
-    DCHECK_LT(shift, 8 * static_cast<int>(sizeof(result)));
-    result |= (chunk & 0x7f) << shift;
-    shift += 7;
-  } while (chunk >= 128);
-
-  // Sign extend the result if the last chunk has the sign bit set.
-  if (chunk & kSignBitMask) result |= (~0ull) << shift;
-
-  DCHECK_NOT_NULL(encoded_size);
-  *encoded_size = static_cast<int>(current - encoded);
-
-  return result;
-}
-
-#ifdef ENABLE_DISASSEMBLER
-
-namespace {
-
-class StreamModifiersScope final {
- public:
-  explicit StreamModifiersScope(std::ostream* stream)
-      : stream_(stream), flags_(stream->flags()) {}
-  ~StreamModifiersScope() { stream_->flags(flags_); }
-
- private:
-  std::ostream* stream_;
-  std::ios::fmtflags flags_;
-};
-
-}  // namespace
-
-// static
-void EhFrameDisassembler::DumpDwarfDirectives(std::ostream& stream,  // NOLINT
-                                              const byte* start,
-                                              const byte* end) {
-  StreamModifiersScope modifiers_scope(&stream);
-
-  EhFrameIterator eh_frame_iterator(start, end);
-  uint32_t offset_in_procedure = 0;
-
-  while (!eh_frame_iterator.Done()) {
-    stream << eh_frame_iterator.current_address() << "  ";
-
-    byte bytecode = eh_frame_iterator.GetNextByte();
-
-    if (((bytecode >> EhFrameConstants::kLocationMaskSize) & 0xff) ==
-        EhFrameConstants::kLocationTag) {
-      int value = (bytecode & EhFrameConstants::kLocationMask) *
-                  EhFrameConstants::kCodeAlignmentFactor;
-      offset_in_procedure += value;
-      stream << "| pc_offset=" << offset_in_procedure << " (delta=" << value
-             << ")\n";
-      continue;
-    }
-
-    if (((bytecode >> EhFrameConstants::kSavedRegisterMaskSize) & 0xff) ==
-        EhFrameConstants::kSavedRegisterTag) {
-      uint32_t decoded_offset = eh_frame_iterator.GetNextULeb128();
-      stream << "| " << DwarfRegisterCodeToString(
-                            bytecode & EhFrameConstants::kLocationMask)
-             << " saved at base" << std::showpos
-             << decoded_offset * EhFrameConstants::kDataAlignmentFactor
-             << std::noshowpos << '\n';
-      continue;
-    }
-
-    if (((bytecode >> EhFrameConstants::kFollowInitialRuleMaskSize) & 0xff) ==
-        EhFrameConstants::kFollowInitialRuleTag) {
-      stream << "| " << DwarfRegisterCodeToString(
-                            bytecode & EhFrameConstants::kLocationMask)
-             << " follows rule in CIE\n";
-      continue;
-    }
-
-    switch (static_cast<EhFrameConstants::DwarfOpcodes>(bytecode)) {
-      case EhFrameConstants::DwarfOpcodes::kOffsetExtendedSf: {
-        stream << "| "
-               << DwarfRegisterCodeToString(eh_frame_iterator.GetNextULeb128());
-        int32_t decoded_offset = eh_frame_iterator.GetNextSLeb128();
-        stream << " saved at base" << std::showpos
-               << decoded_offset * EhFrameConstants::kDataAlignmentFactor
-               << std::noshowpos << '\n';
-        break;
-      }
-      case EhFrameConstants::DwarfOpcodes::kAdvanceLoc1: {
-        int value = eh_frame_iterator.GetNextByte() *
-                    EhFrameConstants::kCodeAlignmentFactor;
-        offset_in_procedure += value;
-        stream << "| pc_offset=" << offset_in_procedure << " (delta=" << value
-               << ")\n";
-        break;
-      }
-      case EhFrameConstants::DwarfOpcodes::kAdvanceLoc2: {
-        int value = eh_frame_iterator.GetNextUInt16() *
-                    EhFrameConstants::kCodeAlignmentFactor;
-        offset_in_procedure += value;
-        stream << "| pc_offset=" << offset_in_procedure << " (delta=" << value
-               << ")\n";
-        break;
-      }
-      case EhFrameConstants::DwarfOpcodes::kAdvanceLoc4: {
-        int value = eh_frame_iterator.GetNextUInt32() *
-                    EhFrameConstants::kCodeAlignmentFactor;
-        offset_in_procedure += value;
-        stream << "| pc_offset=" << offset_in_procedure << " (delta=" << value
-               << ")\n";
-        break;
-      }
-      case EhFrameConstants::DwarfOpcodes::kDefCfa: {
-        uint32_t base_register = eh_frame_iterator.GetNextULeb128();
-        uint32_t base_offset = eh_frame_iterator.GetNextULeb128();
-        stream << "| base_register=" << DwarfRegisterCodeToString(base_register)
-               << ", base_offset=" << base_offset << '\n';
-        break;
-      }
-      case EhFrameConstants::DwarfOpcodes::kDefCfaOffset: {
-        stream << "| base_offset=" << eh_frame_iterator.GetNextULeb128()
-               << '\n';
-        break;
-      }
-      case EhFrameConstants::DwarfOpcodes::kDefCfaRegister: {
-        stream << "| base_register="
-               << DwarfRegisterCodeToString(eh_frame_iterator.GetNextULeb128())
-               << '\n';
-        break;
-      }
-      case EhFrameConstants::DwarfOpcodes::kSameValue: {
-        stream << "| "
-               << DwarfRegisterCodeToString(eh_frame_iterator.GetNextULeb128())
-               << " not modified from previous frame\n";
-        break;
-      }
-      case EhFrameConstants::DwarfOpcodes::kNop:
-        stream << "| nop\n";
-        break;
-      default:
-        UNREACHABLE();
-        return;
-    }
-  }
-}
-
-void EhFrameDisassembler::DisassembleToStream(std::ostream& stream) {  // NOLINT
-  // The encoded CIE size does not include the size field itself.
-  const int cie_size = ReadUnalignedUInt32(start_) + kInt32Size;
-  const int fde_offset = cie_size;
-
-  const byte* cie_directives_start =
-      start_ + EhFrameConstants::kInitialStateOffsetInCie;
-  const byte* cie_directives_end = start_ + cie_size;
-  DCHECK_LE(cie_directives_start, cie_directives_end);
-
-  stream << reinterpret_cast<const void*>(start_) << "  .eh_frame: CIE\n";
-  DumpDwarfDirectives(stream, cie_directives_start, cie_directives_end);
-
-  const byte* procedure_offset_address =
-      start_ + fde_offset + EhFrameConstants::kProcedureAddressOffsetInFde;
-  int32_t procedure_offset =
-      ReadUnalignedValue<int32_t>(procedure_offset_address);
-
-  const byte* procedure_size_address =
-      start_ + fde_offset + EhFrameConstants::kProcedureSizeOffsetInFde;
-  uint32_t procedure_size = ReadUnalignedUInt32(procedure_size_address);
-
-  const byte* fde_start = start_ + fde_offset;
-  stream << reinterpret_cast<const void*>(fde_start) << "  .eh_frame: FDE\n"
-         << reinterpret_cast<const void*>(procedure_offset_address)
-         << "  | procedure_offset=" << procedure_offset << '\n'
-         << reinterpret_cast<const void*>(procedure_size_address)
-         << "  | procedure_size=" << procedure_size << '\n';
-
-  const int fde_directives_offset = fde_offset + 4 * kInt32Size + 1;
-
-  const byte* fde_directives_start = start_ + fde_directives_offset;
-  const byte* fde_directives_end = end_ - EhFrameConstants::kEhFrameHdrSize -
-                                   EhFrameConstants::kEhFrameTerminatorSize;
-  DCHECK_LE(fde_directives_start, fde_directives_end);
-
-  DumpDwarfDirectives(stream, fde_directives_start, fde_directives_end);
-
-  const byte* fde_terminator_start = fde_directives_end;
-  stream << reinterpret_cast<const void*>(fde_terminator_start)
-         << "  .eh_frame: terminator\n";
-
-  const byte* eh_frame_hdr_start =
-      fde_terminator_start + EhFrameConstants::kEhFrameTerminatorSize;
-  stream << reinterpret_cast<const void*>(eh_frame_hdr_start)
-         << "  .eh_frame_hdr\n";
-}
-
-#endif
-
-}  // namespace internal
-}  // namespace v8