diff options
Diffstat (limited to 'llvm/lib/DebugInfo/DWARF/DWARFExpression.cpp')
| -rw-r--r-- | llvm/lib/DebugInfo/DWARF/DWARFExpression.cpp | 344 | 
1 files changed, 344 insertions, 0 deletions
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFExpression.cpp b/llvm/lib/DebugInfo/DWARF/DWARFExpression.cpp new file mode 100644 index 0000000000000..5009b1b7b4127 --- /dev/null +++ b/llvm/lib/DebugInfo/DWARF/DWARFExpression.cpp @@ -0,0 +1,344 @@ +//===-- DWARFExpression.cpp -----------------------------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// + +#include "llvm/DebugInfo/DWARF/DWARFExpression.h" +#include "llvm/DebugInfo/DWARF/DWARFUnit.h" +#include "llvm/BinaryFormat/Dwarf.h" +#include "llvm/MC/MCRegisterInfo.h" +#include "llvm/Support/Format.h" +#include <cassert> +#include <cstdint> +#include <vector> + +using namespace llvm; +using namespace dwarf; + +namespace llvm { + +typedef std::vector<DWARFExpression::Operation::Description> DescVector; + +static DescVector getDescriptions() { +  DescVector Descriptions; +  typedef DWARFExpression::Operation Op; +  typedef Op::Description Desc; + +  Descriptions.resize(0xff); +  Descriptions[DW_OP_addr] = Desc(Op::Dwarf2, Op::SizeAddr); +  Descriptions[DW_OP_deref] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_const1u] = Desc(Op::Dwarf2, Op::Size1); +  Descriptions[DW_OP_const1s] = Desc(Op::Dwarf2, Op::SignedSize1); +  Descriptions[DW_OP_const2u] = Desc(Op::Dwarf2, Op::Size2); +  Descriptions[DW_OP_const2s] = Desc(Op::Dwarf2, Op::SignedSize2); +  Descriptions[DW_OP_const4u] = Desc(Op::Dwarf2, Op::Size4); +  Descriptions[DW_OP_const4s] = Desc(Op::Dwarf2, Op::SignedSize4); +  Descriptions[DW_OP_const8u] = Desc(Op::Dwarf2, Op::Size8); +  Descriptions[DW_OP_const8s] = Desc(Op::Dwarf2, Op::SignedSize8); +  Descriptions[DW_OP_constu] = Desc(Op::Dwarf2, Op::SizeLEB); +  Descriptions[DW_OP_consts] = Desc(Op::Dwarf2, Op::SignedSizeLEB); +  Descriptions[DW_OP_dup] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_drop] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_over] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_pick] = Desc(Op::Dwarf2, Op::Size1); +  Descriptions[DW_OP_swap] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_rot] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_xderef] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_abs] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_and] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_div] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_minus] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_mod] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_mul] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_neg] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_not] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_or] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_plus] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_plus_uconst] = Desc(Op::Dwarf2, Op::SizeLEB); +  Descriptions[DW_OP_shl] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_shr] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_shra] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_xor] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_skip] = Desc(Op::Dwarf2, Op::SignedSize2); +  Descriptions[DW_OP_bra] = Desc(Op::Dwarf2, Op::SignedSize2); +  Descriptions[DW_OP_eq] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_ge] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_gt] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_le] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_lt] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_ne] = Desc(Op::Dwarf2); +  for (uint16_t LA = DW_OP_lit0; LA <= DW_OP_lit31; ++LA) +    Descriptions[LA] = Desc(Op::Dwarf2); +  for (uint16_t LA = DW_OP_reg0; LA <= DW_OP_reg31; ++LA) +    Descriptions[LA] = Desc(Op::Dwarf2); +  for (uint16_t LA = DW_OP_breg0; LA <= DW_OP_breg31; ++LA) +    Descriptions[LA] = Desc(Op::Dwarf2, Op::SignedSizeLEB); +  Descriptions[DW_OP_regx] = Desc(Op::Dwarf2, Op::SizeLEB); +  Descriptions[DW_OP_fbreg] = Desc(Op::Dwarf2, Op::SignedSizeLEB); +  Descriptions[DW_OP_bregx] = Desc(Op::Dwarf2, Op::SizeLEB, Op::SignedSizeLEB); +  Descriptions[DW_OP_piece] = Desc(Op::Dwarf2, Op::SizeLEB); +  Descriptions[DW_OP_deref_size] = Desc(Op::Dwarf2, Op::Size1); +  Descriptions[DW_OP_xderef_size] = Desc(Op::Dwarf2, Op::Size1); +  Descriptions[DW_OP_nop] = Desc(Op::Dwarf2); +  Descriptions[DW_OP_push_object_address] = Desc(Op::Dwarf3); +  Descriptions[DW_OP_call2] = Desc(Op::Dwarf3, Op::Size2); +  Descriptions[DW_OP_call4] = Desc(Op::Dwarf3, Op::Size4); +  Descriptions[DW_OP_call_ref] = Desc(Op::Dwarf3, Op::SizeRefAddr); +  Descriptions[DW_OP_form_tls_address] = Desc(Op::Dwarf3); +  Descriptions[DW_OP_call_frame_cfa] = Desc(Op::Dwarf3); +  Descriptions[DW_OP_bit_piece] = Desc(Op::Dwarf3, Op::SizeLEB, Op::SizeLEB); +  Descriptions[DW_OP_implicit_value] = +      Desc(Op::Dwarf3, Op::SizeLEB, Op::SizeBlock); +  Descriptions[DW_OP_stack_value] = Desc(Op::Dwarf3); +  Descriptions[DW_OP_GNU_push_tls_address] = Desc(Op::Dwarf3); +  Descriptions[DW_OP_addrx] = Desc(Op::Dwarf4, Op::SizeLEB); +  Descriptions[DW_OP_GNU_addr_index] = Desc(Op::Dwarf4, Op::SizeLEB); +  Descriptions[DW_OP_GNU_const_index] = Desc(Op::Dwarf4, Op::SizeLEB); +  Descriptions[DW_OP_GNU_entry_value] = Desc(Op::Dwarf4, Op::SizeLEB); + +  Descriptions[DW_OP_convert] = Desc(Op::Dwarf5, Op::BaseTypeRef); +  Descriptions[DW_OP_entry_value] = Desc(Op::Dwarf5, Op::SizeLEB); + +  return Descriptions; +} + +static DWARFExpression::Operation::Description getOpDesc(unsigned OpCode) { +  // FIXME: Make this constexpr once all compilers are smart enough to do it. +  static DescVector Descriptions = getDescriptions(); +  // Handle possible corrupted or unsupported operation. +  if (OpCode >= Descriptions.size()) +    return {}; +  return Descriptions[OpCode]; +} + +static uint8_t getRefAddrSize(uint8_t AddrSize, uint16_t Version) { +  return (Version == 2) ? AddrSize : 4; +} + +bool DWARFExpression::Operation::extract(DataExtractor Data, uint16_t Version, +                                         uint8_t AddressSize, uint64_t Offset) { +  Opcode = Data.getU8(&Offset); + +  Desc = getOpDesc(Opcode); +  if (Desc.Version == Operation::DwarfNA) { +    EndOffset = Offset; +    return false; +  } + +  for (unsigned Operand = 0; Operand < 2; ++Operand) { +    unsigned Size = Desc.Op[Operand]; +    unsigned Signed = Size & Operation::SignBit; + +    if (Size == Operation::SizeNA) +      break; + +    switch (Size & ~Operation::SignBit) { +    case Operation::Size1: +      Operands[Operand] = Data.getU8(&Offset); +      if (Signed) +        Operands[Operand] = (int8_t)Operands[Operand]; +      break; +    case Operation::Size2: +      Operands[Operand] = Data.getU16(&Offset); +      if (Signed) +        Operands[Operand] = (int16_t)Operands[Operand]; +      break; +    case Operation::Size4: +      Operands[Operand] = Data.getU32(&Offset); +      if (Signed) +        Operands[Operand] = (int32_t)Operands[Operand]; +      break; +    case Operation::Size8: +      Operands[Operand] = Data.getU64(&Offset); +      break; +    case Operation::SizeAddr: +      if (AddressSize == 8) { +        Operands[Operand] = Data.getU64(&Offset); +      } else if (AddressSize == 4) { +        Operands[Operand] = Data.getU32(&Offset); +      } else { +        assert(AddressSize == 2); +        Operands[Operand] = Data.getU16(&Offset); +      } +      break; +    case Operation::SizeRefAddr: +      if (getRefAddrSize(AddressSize, Version) == 8) { +        Operands[Operand] = Data.getU64(&Offset); +      } else if (getRefAddrSize(AddressSize, Version) == 4) { +        Operands[Operand] = Data.getU32(&Offset); +      } else { +        assert(getRefAddrSize(AddressSize, Version) == 2); +        Operands[Operand] = Data.getU16(&Offset); +      } +      break; +    case Operation::SizeLEB: +      if (Signed) +        Operands[Operand] = Data.getSLEB128(&Offset); +      else +        Operands[Operand] = Data.getULEB128(&Offset); +      break; +    case Operation::BaseTypeRef: +      Operands[Operand] = Data.getULEB128(&Offset); +      break; +    case Operation::SizeBlock: +      // We need a size, so this cannot be the first operand +      if (Operand == 0) +        return false; +      // Store the offset of the block as the value. +      Operands[Operand] = Offset; +      Offset += Operands[Operand - 1]; +      break; +    default: +      llvm_unreachable("Unknown DWARFExpression Op size"); +    } + +    OperandEndOffsets[Operand] = Offset; +  } + +  EndOffset = Offset; +  return true; +} + +static bool prettyPrintRegisterOp(raw_ostream &OS, uint8_t Opcode, +                                  uint64_t Operands[2], +                                  const MCRegisterInfo *MRI, bool isEH) { +  if (!MRI) +    return false; + +  uint64_t DwarfRegNum; +  unsigned OpNum = 0; + +  if (Opcode == DW_OP_bregx || Opcode == DW_OP_regx) +    DwarfRegNum = Operands[OpNum++]; +  else if (Opcode >= DW_OP_breg0 && Opcode < DW_OP_bregx) +    DwarfRegNum = Opcode - DW_OP_breg0; +  else +    DwarfRegNum = Opcode - DW_OP_reg0; + +  if (Optional<unsigned> LLVMRegNum = MRI->getLLVMRegNum(DwarfRegNum, isEH)) { +    if (const char *RegName = MRI->getName(*LLVMRegNum)) { +      if ((Opcode >= DW_OP_breg0 && Opcode <= DW_OP_breg31) || +          Opcode == DW_OP_bregx) +        OS << format(" %s%+" PRId64, RegName, Operands[OpNum]); +      else +        OS << ' ' << RegName; +      return true; +    } +  } + +  return false; +} + +bool DWARFExpression::Operation::print(raw_ostream &OS, +                                       const DWARFExpression *Expr, +                                       const MCRegisterInfo *RegInfo, +                                       DWARFUnit *U, +                                       bool isEH) { +  if (Error) { +    OS << "<decoding error>"; +    return false; +  } + +  StringRef Name = OperationEncodingString(Opcode); +  assert(!Name.empty() && "DW_OP has no name!"); +  OS << Name; + +  if ((Opcode >= DW_OP_breg0 && Opcode <= DW_OP_breg31) || +      (Opcode >= DW_OP_reg0 && Opcode <= DW_OP_reg31) || +      Opcode == DW_OP_bregx || Opcode == DW_OP_regx) +    if (prettyPrintRegisterOp(OS, Opcode, Operands, RegInfo, isEH)) +      return true; + +  for (unsigned Operand = 0; Operand < 2; ++Operand) { +    unsigned Size = Desc.Op[Operand]; +    unsigned Signed = Size & Operation::SignBit; + +    if (Size == Operation::SizeNA) +      break; + +    if (Size == Operation::BaseTypeRef && U) { +      auto Die = U->getDIEForOffset(U->getOffset() + Operands[Operand]); +      if (Die && Die.getTag() == dwarf::DW_TAG_base_type) { +        OS << format(" (0x%08" PRIx64 ")", U->getOffset() + Operands[Operand]); +        if (auto Name = Die.find(dwarf::DW_AT_name)) +          OS << " \"" << Name->getAsCString() << "\""; +      } else { +        OS << format(" <invalid base_type ref: 0x%" PRIx64 ">", +                     Operands[Operand]); +      } +    } else if (Size == Operation::SizeBlock) { +      uint64_t Offset = Operands[Operand]; +      for (unsigned i = 0; i < Operands[Operand - 1]; ++i) +        OS << format(" 0x%02x", Expr->Data.getU8(&Offset)); +    } else { +      if (Signed) +        OS << format(" %+" PRId64, (int64_t)Operands[Operand]); +      else if (Opcode != DW_OP_entry_value && +               Opcode != DW_OP_GNU_entry_value) +        OS << format(" 0x%" PRIx64, Operands[Operand]); +    } +  } +  return true; +} + +void DWARFExpression::print(raw_ostream &OS, const MCRegisterInfo *RegInfo, +                            DWARFUnit *U, bool IsEH) const { +  uint32_t EntryValExprSize = 0; +  for (auto &Op : *this) { +    if (!Op.print(OS, this, RegInfo, U, IsEH)) { +      uint64_t FailOffset = Op.getEndOffset(); +      while (FailOffset < Data.getData().size()) +        OS << format(" %02x", Data.getU8(&FailOffset)); +      return; +    } + +    if (Op.getCode() == DW_OP_entry_value || +        Op.getCode() == DW_OP_GNU_entry_value) { +      OS << "("; +      EntryValExprSize = Op.getRawOperand(0); +      continue; +    } + +    if (EntryValExprSize) { +      EntryValExprSize--; +      if (EntryValExprSize == 0) +        OS << ")"; +    } + +    if (Op.getEndOffset() < Data.getData().size()) +      OS << ", "; +  } +} + +bool DWARFExpression::Operation::verify(DWARFUnit *U) { + +  for (unsigned Operand = 0; Operand < 2; ++Operand) { +    unsigned Size = Desc.Op[Operand]; + +    if (Size == Operation::SizeNA) +      break; + +    if (Size == Operation::BaseTypeRef) { +      auto Die = U->getDIEForOffset(U->getOffset() + Operands[Operand]); +      if (!Die || Die.getTag() != dwarf::DW_TAG_base_type) { +        Error = true; +        return false; +      } +    } +  } + +  return true; +} + +bool DWARFExpression::verify(DWARFUnit *U) { +  for (auto &Op : *this) +    if (!Op.verify(U)) +      return false; + +  return true; +} + +} // namespace llvm  | 
