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Unified Diff: src/eh-frame.cc

Issue 2143033002: Revert of Implement .eh_frame writer and disassembler. (Closed) Base URL: https://chromium.googlesource.com/v8/v8.git@eh-frame-base
Patch Set: Created 4 years, 5 months ago
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Index: src/eh-frame.cc
diff --git a/src/eh-frame.cc b/src/eh-frame.cc
index cceed6620a49645000919b8d8b9470c3aeed2338..af85e0b8d5f7143beb3c5243513a69fef0f5f919 100644
--- a/src/eh-frame.cc
+++ b/src/eh-frame.cc
@@ -3,632 +3,94 @@
// 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
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