1 files changed, 340 insertions, 0 deletions
diff --git a/llvm/tools/llvm-readobj/Win64EHDumper.cpp b/llvm/tools/llvm-readobj/Win64EHDumper.cpp
new file mode 100644
index 000000000000..fa268ce9d434
--- /dev/null
+++ b/llvm/tools/llvm-readobj/Win64EHDumper.cpp
@@ -0,0 +1,340 @@
+//===- Win64EHDumper.cpp - Win64 EH Printer ---------------------*- C++ -*-===//
+//
+// 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 "Win64EHDumper.h"
+#include "llvm-readobj.h"
+#include "llvm/Object/COFF.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/Format.h"
+
+using namespace llvm;
+using namespace llvm::object;
+using namespace llvm::Win64EH;
+
+static const EnumEntry<unsigned> UnwindFlags[] = {
+  { "ExceptionHandler", UNW_ExceptionHandler },
+  { "TerminateHandler", UNW_TerminateHandler },
+  { "ChainInfo"       , UNW_ChainInfo        }
+};
+
+static const EnumEntry<unsigned> UnwindOpInfo[] = {
+  { "RAX",  0 },
+  { "RCX",  1 },
+  { "RDX",  2 },
+  { "RBX",  3 },
+  { "RSP",  4 },
+  { "RBP",  5 },
+  { "RSI",  6 },
+  { "RDI",  7 },
+  { "R8",   8 },
+  { "R9",   9 },
+  { "R10", 10 },
+  { "R11", 11 },
+  { "R12", 12 },
+  { "R13", 13 },
+  { "R14", 14 },
+  { "R15", 15 }
+};
+
+static uint64_t getOffsetOfLSDA(const UnwindInfo& UI) {
+  return static_cast<const char*>(UI.getLanguageSpecificData())
+         - reinterpret_cast<const char*>(&UI);
+}
+
+static uint32_t getLargeSlotValue(ArrayRef<UnwindCode> UC) {
+  if (UC.size() < 3)
+    return 0;
+  return UC[1].FrameOffset + (static_cast<uint32_t>(UC[2].FrameOffset) << 16);
+}
+
+// Returns the name of the unwind code.
+static StringRef getUnwindCodeTypeName(uint8_t Code) {
+  switch (Code) {
+  default: llvm_unreachable("Invalid unwind code");
+  case UOP_PushNonVol: return "PUSH_NONVOL";
+  case UOP_AllocLarge: return "ALLOC_LARGE";
+  case UOP_AllocSmall: return "ALLOC_SMALL";
+  case UOP_SetFPReg: return "SET_FPREG";
+  case UOP_SaveNonVol: return "SAVE_NONVOL";
+  case UOP_SaveNonVolBig: return "SAVE_NONVOL_FAR";
+  case UOP_SaveXMM128: return "SAVE_XMM128";
+  case UOP_SaveXMM128Big: return "SAVE_XMM128_FAR";
+  case UOP_PushMachFrame: return "PUSH_MACHFRAME";
+  }
+}
+
+// Returns the name of a referenced register.
+static StringRef getUnwindRegisterName(uint8_t Reg) {
+  switch (Reg) {
+  default: llvm_unreachable("Invalid register");
+  case 0: return "RAX";
+  case 1: return "RCX";
+  case 2: return "RDX";
+  case 3: return "RBX";
+  case 4: return "RSP";
+  case 5: return "RBP";
+  case 6: return "RSI";
+  case 7: return "RDI";
+  case 8: return "R8";
+  case 9: return "R9";
+  case 10: return "R10";
+  case 11: return "R11";
+  case 12: return "R12";
+  case 13: return "R13";
+  case 14: return "R14";
+  case 15: return "R15";
+  }
+}
+
+// Calculates the number of array slots required for the unwind code.
+static unsigned getNumUsedSlots(const UnwindCode &UnwindCode) {
+  switch (UnwindCode.getUnwindOp()) {
+  default: llvm_unreachable("Invalid unwind code");
+  case UOP_PushNonVol:
+  case UOP_AllocSmall:
+  case UOP_SetFPReg:
+  case UOP_PushMachFrame:
+    return 1;
+  case UOP_SaveNonVol:
+  case UOP_SaveXMM128:
+    return 2;
+  case UOP_SaveNonVolBig:
+  case UOP_SaveXMM128Big:
+    return 3;
+  case UOP_AllocLarge:
+    return (UnwindCode.getOpInfo() == 0) ? 2 : 3;
+  }
+}
+
+static std::string formatSymbol(const Dumper::Context &Ctx,
+                                const coff_section *Section, uint64_t Offset,
+                                uint32_t Displacement) {
+  std::string Buffer;
+  raw_string_ostream OS(Buffer);
+
+  SymbolRef Symbol;
+  if (!Ctx.ResolveSymbol(Section, Offset, Symbol, Ctx.UserData)) {
+    Expected<StringRef> Name = Symbol.getName();
+    if (Name) {
+      OS << *Name;
+      if (Displacement > 0)
+        OS << format(" +0x%X (0x%" PRIX64 ")", Displacement, Offset);
+      else
+        OS << format(" (0x%" PRIX64 ")", Offset);
+      return OS.str();
+    } else {
+      // TODO: Actually report errors helpfully.
+      consumeError(Name.takeError());
+    }
+  }
+
+  OS << format(" (0x%" PRIX64 ")", Offset);
+  return OS.str();
+}
+
+static std::error_code resolveRelocation(const Dumper::Context &Ctx,
+                                         const coff_section *Section,
+                                         uint64_t Offset,
+                                         const coff_section *&ResolvedSection,
+                                         uint64_t &ResolvedAddress) {
+  SymbolRef Symbol;
+  if (std::error_code EC =
+          Ctx.ResolveSymbol(Section, Offset, Symbol, Ctx.UserData))
+    return EC;
+
+  Expected<uint64_t> ResolvedAddressOrErr = Symbol.getAddress();
+  if (!ResolvedAddressOrErr)
+    return errorToErrorCode(ResolvedAddressOrErr.takeError());
+  ResolvedAddress = *ResolvedAddressOrErr;
+
+  Expected<section_iterator> SI = Symbol.getSection();
+  if (!SI)
+    return errorToErrorCode(SI.takeError());
+  ResolvedSection = Ctx.COFF.getCOFFSection(**SI);
+  return std::error_code();
+}
+
+namespace llvm {
+namespace Win64EH {
+void Dumper::printRuntimeFunctionEntry(const Context &Ctx,
+                                       const coff_section *Section,
+                                       uint64_t Offset,
+                                       const RuntimeFunction &RF) {
+  SW.printString("StartAddress",
+                 formatSymbol(Ctx, Section, Offset + 0, RF.StartAddress));
+  SW.printString("EndAddress",
+                 formatSymbol(Ctx, Section, Offset + 4, RF.EndAddress));
+  SW.printString("UnwindInfoAddress",
+                 formatSymbol(Ctx, Section, Offset + 8, RF.UnwindInfoOffset));
+}
+
+// Prints one unwind code. Because an unwind code can occupy up to 3 slots in
+// the unwind codes array, this function requires that the correct number of
+// slots is provided.
+void Dumper::printUnwindCode(const UnwindInfo& UI, ArrayRef<UnwindCode> UC) {
+  assert(UC.size() >= getNumUsedSlots(UC[0]));
+
+  SW.startLine() << format("0x%02X: ", unsigned(UC[0].u.CodeOffset))
+                 << getUnwindCodeTypeName(UC[0].getUnwindOp());
+
+  switch (UC[0].getUnwindOp()) {
+  case UOP_PushNonVol:
+    OS << " reg=" << getUnwindRegisterName(UC[0].getOpInfo());
+    break;
+
+  case UOP_AllocLarge:
+    OS << " size="
+       << ((UC[0].getOpInfo() == 0) ? UC[1].FrameOffset * 8
+                                    : getLargeSlotValue(UC));
+    break;
+
+  case UOP_AllocSmall:
+    OS << " size=" << (UC[0].getOpInfo() + 1) * 8;
+    break;
+
+  case UOP_SetFPReg:
+    if (UI.getFrameRegister() == 0)
+      OS << " reg=<invalid>";
+    else
+      OS << " reg=" << getUnwindRegisterName(UI.getFrameRegister())
+         << format(", offset=0x%X", UI.getFrameOffset() * 16);
+    break;
+
+  case UOP_SaveNonVol:
+    OS << " reg=" << getUnwindRegisterName(UC[0].getOpInfo())
+       << format(", offset=0x%X", UC[1].FrameOffset * 8);
+    break;
+
+  case UOP_SaveNonVolBig:
+    OS << " reg=" << getUnwindRegisterName(UC[0].getOpInfo())
+       << format(", offset=0x%X", getLargeSlotValue(UC));
+    break;
+
+  case UOP_SaveXMM128:
+    OS << " reg=XMM" << static_cast<uint32_t>(UC[0].getOpInfo())
+       << format(", offset=0x%X", UC[1].FrameOffset * 16);
+    break;
+
+  case UOP_SaveXMM128Big:
+    OS << " reg=XMM" << static_cast<uint32_t>(UC[0].getOpInfo())
+       << format(", offset=0x%X", getLargeSlotValue(UC));
+    break;
+
+  case UOP_PushMachFrame:
+    OS << " errcode=" << (UC[0].getOpInfo() == 0 ? "no" : "yes");
+    break;
+  }
+
+  OS << "\n";
+}
+
+void Dumper::printUnwindInfo(const Context &Ctx, const coff_section *Section,
+                             off_t Offset, const UnwindInfo &UI) {
+  DictScope UIS(SW, "UnwindInfo");
+  SW.printNumber("Version", UI.getVersion());
+  SW.printFlags("Flags", UI.getFlags(), makeArrayRef(UnwindFlags));
+  SW.printNumber("PrologSize", UI.PrologSize);
+  if (UI.getFrameRegister()) {
+    SW.printEnum("FrameRegister", UI.getFrameRegister(),
+                 makeArrayRef(UnwindOpInfo));
+    SW.printHex("FrameOffset", UI.getFrameOffset());
+  } else {
+    SW.printString("FrameRegister", StringRef("-"));
+    SW.printString("FrameOffset", StringRef("-"));
+  }
+
+  SW.printNumber("UnwindCodeCount", UI.NumCodes);
+  {
+    ListScope UCS(SW, "UnwindCodes");
+    ArrayRef<UnwindCode> UC(&UI.UnwindCodes[0], UI.NumCodes);
+    for (const UnwindCode *UCI = UC.begin(), *UCE = UC.end(); UCI < UCE; ++UCI) {
+      unsigned UsedSlots = getNumUsedSlots(*UCI);
+      if (UsedSlots > UC.size()) {
+        errs() << "corrupt unwind data";
+        return;
+      }
+
+      printUnwindCode(UI, makeArrayRef(UCI, UCE));
+      UCI = UCI + UsedSlots - 1;
+    }
+  }
+
+  uint64_t LSDAOffset = Offset + getOffsetOfLSDA(UI);
+  if (UI.getFlags() & (UNW_ExceptionHandler | UNW_TerminateHandler)) {
+    SW.printString("Handler",
+                   formatSymbol(Ctx, Section, LSDAOffset,
+                                UI.getLanguageSpecificHandlerOffset()));
+  } else if (UI.getFlags() & UNW_ChainInfo) {
+    if (const RuntimeFunction *Chained = UI.getChainedFunctionEntry()) {
+      DictScope CS(SW, "Chained");
+      printRuntimeFunctionEntry(Ctx, Section, LSDAOffset, *Chained);
+    }
+  }
+}
+
+void Dumper::printRuntimeFunction(const Context &Ctx,
+                                  const coff_section *Section,
+                                  uint64_t SectionOffset,
+                                  const RuntimeFunction &RF) {
+  DictScope RFS(SW, "RuntimeFunction");
+  printRuntimeFunctionEntry(Ctx, Section, SectionOffset, RF);
+
+  const coff_section *XData;
+  uint64_t Offset;
+  resolveRelocation(Ctx, Section, SectionOffset + 8, XData, Offset);
+
+  ArrayRef<uint8_t> Contents;
+  if (Error E = Ctx.COFF.getSectionContents(XData, Contents))
+    reportError(std::move(E), Ctx.COFF.getFileName());
+
+  if (Contents.empty())
+    return;
+
+  Offset = Offset + RF.UnwindInfoOffset;
+  if (Offset > Contents.size())
+    return;
+
+  const auto UI = reinterpret_cast<const UnwindInfo*>(Contents.data() + Offset);
+  printUnwindInfo(Ctx, XData, Offset, *UI);
+}
+
+void Dumper::printData(const Context &Ctx) {
+  for (const auto &Section : Ctx.COFF.sections()) {
+    StringRef Name;
+    if (Expected<StringRef> NameOrErr = Section.getName())
+      Name = *NameOrErr;
+    else
+      consumeError(NameOrErr.takeError());
+
+    if (Name != ".pdata" && !Name.startswith(".pdata$"))
+      continue;
+
+    const coff_section *PData = Ctx.COFF.getCOFFSection(Section);
+    ArrayRef<uint8_t> Contents;
+
+    if (Error E = Ctx.COFF.getSectionContents(PData, Contents))
+      reportError(std::move(E), Ctx.COFF.getFileName());
+    if (Contents.empty())
+      continue;
+
+    const RuntimeFunction *Entries =
+      reinterpret_cast<const RuntimeFunction *>(Contents.data());
+    const size_t Count = Contents.size() / sizeof(RuntimeFunction);
+    ArrayRef<RuntimeFunction> RuntimeFunctions(Entries, Count);
+
+    size_t Index = 0;
+    for (const auto &RF : RuntimeFunctions) {
+      printRuntimeFunction(Ctx, Ctx.COFF.getCOFFSection(Section),
+                           Index * sizeof(RuntimeFunction), RF);
+      ++Index;
+    }
+  }
+}
+}
+}
+