llvm-project/llvm/tools/llvm-readobj/Win64EHDumper.cpp

427 lines
14 KiB
C++

//===- 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;
const EnumEntry<unsigned> UnwindFlags[] = {
{ "ExceptionHandler", UNW_ExceptionHandler },
{ "TerminateHandler", UNW_TerminateHandler },
{ "ChainInfo" , UNW_ChainInfo }
};
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::error_code getSymbol(const COFFObjectFile &COFF, uint64_t VA,
object::SymbolRef &Sym) {
for (const auto &Symbol : COFF.symbols()) {
Expected<uint64_t> Address = Symbol.getAddress();
if (!Address)
return errorToErrorCode(Address.takeError());
if (*Address == VA) {
Sym = Symbol;
return std::error_code();
}
}
return inconvertibleErrorCode();
}
static object::SymbolRef getPreferredSymbol(const COFFObjectFile &COFF,
object::SymbolRef Sym,
uint32_t &SymbolOffset,
bool IsRangeEnd) {
// The symbol resolved by ResolveSymbol can be any internal
// nondescriptive symbol; try to resolve a more descriptive one.
COFFSymbolRef CoffSym = COFF.getCOFFSymbol(Sym);
if (CoffSym.getStorageClass() != COFF::IMAGE_SYM_CLASS_LABEL &&
CoffSym.getSectionDefinition() == nullptr)
return Sym;
for (const auto &S : COFF.symbols()) {
COFFSymbolRef CS = COFF.getCOFFSymbol(S);
if (CS.getSectionNumber() == CoffSym.getSectionNumber() &&
CS.getValue() <= CoffSym.getValue() + SymbolOffset &&
CS.getStorageClass() != COFF::IMAGE_SYM_CLASS_LABEL &&
CS.getSectionDefinition() == nullptr) {
uint32_t Offset = CoffSym.getValue() + SymbolOffset - CS.getValue();
// For the end of a range, don't pick a symbol with a zero offset;
// prefer a symbol with a small positive offset.
if (Offset <= SymbolOffset && (!IsRangeEnd || Offset > 0)) {
SymbolOffset = Offset;
Sym = S;
CoffSym = CS;
if (CS.isExternal() && SymbolOffset == 0)
return Sym;
}
}
}
return Sym;
}
static std::string formatSymbol(const Dumper::Context &Ctx,
const coff_section *Section, uint64_t Offset,
uint32_t Displacement,
bool IsRangeEnd = false) {
std::string Buffer;
raw_string_ostream OS(Buffer);
SymbolRef Symbol;
if (!Ctx.ResolveSymbol(Section, Offset, Symbol, Ctx.UserData)) {
// We found a relocation at the given offset in the section, pointing
// at a symbol.
// Try to resolve label/section symbols into function names.
Symbol = getPreferredSymbol(Ctx.COFF, Symbol, Displacement, IsRangeEnd);
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());
}
} else if (!getSymbol(Ctx.COFF, Ctx.COFF.getImageBase() + Displacement,
Symbol)) {
Expected<StringRef> Name = Symbol.getName();
if (Name) {
OS << *Name;
OS << format(" (0x%" PRIX64 ")", Ctx.COFF.getImageBase() + Displacement);
return OS.str();
} else {
consumeError(Name.takeError());
}
}
if (Displacement > 0)
OS << format("(0x%" PRIX64 ")", Ctx.COFF.getImageBase() + Displacement);
else
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();
}
static const object::coff_section *
getSectionContaining(const COFFObjectFile &COFF, uint64_t VA) {
for (const auto &Section : COFF.sections()) {
uint64_t Address = Section.getAddress();
uint64_t Size = Section.getSize();
if (VA >= Address && (VA - Address) <= Size)
return COFF.getCOFFSection(Section);
}
return nullptr;
}
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,
/*IsRangeEnd=*/true));
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 = nullptr;
uint64_t Offset;
resolveRelocation(Ctx, Section, SectionOffset + 8, XData, Offset);
Offset = Offset + RF.UnwindInfoOffset;
if (!XData) {
uint64_t Address = Ctx.COFF.getImageBase() + RF.UnwindInfoOffset;
XData = getSectionContaining(Ctx.COFF, Address);
if (!XData)
return;
Offset = RF.UnwindInfoOffset - XData->VirtualAddress;
}
ArrayRef<uint8_t> Contents;
if (Error E = Ctx.COFF.getSectionContents(XData, Contents))
reportError(std::move(E), Ctx.COFF.getFileName());
if (Contents.empty())
return;
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;
}
}
}
}
}