llvm-6502/tools/llvm-objdump/COFFDump.cpp
David Majnemer b3a86a097b Object: Add support for bigobj
This adds support for reading the "bigobj" variant of COFF produced by
cl's /bigobj and mingw's -mbig-obj.

The most significant difference that bigobj brings is more than 2**16
sections to COFF.

bigobj brings a few interesting differences with it:
- It doesn't have a Characteristics field in the file header.
- It doesn't have a SizeOfOptionalHeader field in the file header (it's
  only used in executable files).
- Auxiliary symbol records have the same width as a symbol table entry.
  Since symbol table entries are bigger, so are auxiliary symbol
  records.

Write support will come soon.

Differential Revision: http://reviews.llvm.org/D5259

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@217496 91177308-0d34-0410-b5e6-96231b3b80d8
2014-09-10 12:51:52 +00:00

551 lines
19 KiB
C++

//===-- COFFDump.cpp - COFF-specific dumper ---------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// \file
/// \brief This file implements the COFF-specific dumper for llvm-objdump.
/// It outputs the Win64 EH data structures as plain text.
/// The encoding of the unwind codes is described in MSDN:
/// http://msdn.microsoft.com/en-us/library/ck9asaa9.aspx
///
//===----------------------------------------------------------------------===//
#include "llvm-objdump.h"
#include "llvm/Object/COFF.h"
#include "llvm/Object/ObjectFile.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/SourceMgr.h"
#include "llvm/Support/Win64EH.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
#include <cstring>
#include <system_error>
using namespace llvm;
using namespace object;
using namespace llvm::Win64EH;
// 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 "UOP_PushNonVol";
case UOP_AllocLarge: return "UOP_AllocLarge";
case UOP_AllocSmall: return "UOP_AllocSmall";
case UOP_SetFPReg: return "UOP_SetFPReg";
case UOP_SaveNonVol: return "UOP_SaveNonVol";
case UOP_SaveNonVolBig: return "UOP_SaveNonVolBig";
case UOP_SaveXMM128: return "UOP_SaveXMM128";
case UOP_SaveXMM128Big: return "UOP_SaveXMM128Big";
case UOP_PushMachFrame: return "UOP_PushMachFrame";
}
}
// 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;
}
}
// 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.
static void printUnwindCode(ArrayRef<UnwindCode> UCs) {
assert(UCs.size() >= getNumUsedSlots(UCs[0]));
outs() << format(" 0x%02x: ", unsigned(UCs[0].u.CodeOffset))
<< getUnwindCodeTypeName(UCs[0].getUnwindOp());
switch (UCs[0].getUnwindOp()) {
case UOP_PushNonVol:
outs() << " " << getUnwindRegisterName(UCs[0].getOpInfo());
break;
case UOP_AllocLarge:
if (UCs[0].getOpInfo() == 0) {
outs() << " " << UCs[1].FrameOffset;
} else {
outs() << " " << UCs[1].FrameOffset
+ (static_cast<uint32_t>(UCs[2].FrameOffset) << 16);
}
break;
case UOP_AllocSmall:
outs() << " " << ((UCs[0].getOpInfo() + 1) * 8);
break;
case UOP_SetFPReg:
outs() << " ";
break;
case UOP_SaveNonVol:
outs() << " " << getUnwindRegisterName(UCs[0].getOpInfo())
<< format(" [0x%04x]", 8 * UCs[1].FrameOffset);
break;
case UOP_SaveNonVolBig:
outs() << " " << getUnwindRegisterName(UCs[0].getOpInfo())
<< format(" [0x%08x]", UCs[1].FrameOffset
+ (static_cast<uint32_t>(UCs[2].FrameOffset) << 16));
break;
case UOP_SaveXMM128:
outs() << " XMM" << static_cast<uint32_t>(UCs[0].getOpInfo())
<< format(" [0x%04x]", 16 * UCs[1].FrameOffset);
break;
case UOP_SaveXMM128Big:
outs() << " XMM" << UCs[0].getOpInfo()
<< format(" [0x%08x]", UCs[1].FrameOffset
+ (static_cast<uint32_t>(UCs[2].FrameOffset) << 16));
break;
case UOP_PushMachFrame:
outs() << " " << (UCs[0].getOpInfo() ? "w/o" : "w")
<< " error code";
break;
}
outs() << "\n";
}
static void printAllUnwindCodes(ArrayRef<UnwindCode> UCs) {
for (const UnwindCode *I = UCs.begin(), *E = UCs.end(); I < E; ) {
unsigned UsedSlots = getNumUsedSlots(*I);
if (UsedSlots > UCs.size()) {
outs() << "Unwind data corrupted: Encountered unwind op "
<< getUnwindCodeTypeName((*I).getUnwindOp())
<< " which requires " << UsedSlots
<< " slots, but only " << UCs.size()
<< " remaining in buffer";
return ;
}
printUnwindCode(ArrayRef<UnwindCode>(I, E));
I += UsedSlots;
}
}
// Given a symbol sym this functions returns the address and section of it.
static std::error_code
resolveSectionAndAddress(const COFFObjectFile *Obj, const SymbolRef &Sym,
const coff_section *&ResolvedSection,
uint64_t &ResolvedAddr) {
if (std::error_code EC = Sym.getAddress(ResolvedAddr))
return EC;
section_iterator iter(Obj->section_begin());
if (std::error_code EC = Sym.getSection(iter))
return EC;
ResolvedSection = Obj->getCOFFSection(*iter);
return object_error::success;
}
// Given a vector of relocations for a section and an offset into this section
// the function returns the symbol used for the relocation at the offset.
static std::error_code resolveSymbol(const std::vector<RelocationRef> &Rels,
uint64_t Offset, SymbolRef &Sym) {
for (std::vector<RelocationRef>::const_iterator I = Rels.begin(),
E = Rels.end();
I != E; ++I) {
uint64_t Ofs;
if (std::error_code EC = I->getOffset(Ofs))
return EC;
if (Ofs == Offset) {
Sym = *I->getSymbol();
return object_error::success;
}
}
return object_error::parse_failed;
}
// Given a vector of relocations for a section and an offset into this section
// the function resolves the symbol used for the relocation at the offset and
// returns the section content and the address inside the content pointed to
// by the symbol.
static std::error_code
getSectionContents(const COFFObjectFile *Obj,
const std::vector<RelocationRef> &Rels, uint64_t Offset,
ArrayRef<uint8_t> &Contents, uint64_t &Addr) {
SymbolRef Sym;
if (std::error_code EC = resolveSymbol(Rels, Offset, Sym))
return EC;
const coff_section *Section;
if (std::error_code EC = resolveSectionAndAddress(Obj, Sym, Section, Addr))
return EC;
if (std::error_code EC = Obj->getSectionContents(Section, Contents))
return EC;
return object_error::success;
}
// Given a vector of relocations for a section and an offset into this section
// the function returns the name of the symbol used for the relocation at the
// offset.
static std::error_code resolveSymbolName(const std::vector<RelocationRef> &Rels,
uint64_t Offset, StringRef &Name) {
SymbolRef Sym;
if (std::error_code EC = resolveSymbol(Rels, Offset, Sym))
return EC;
if (std::error_code EC = Sym.getName(Name))
return EC;
return object_error::success;
}
static void printCOFFSymbolAddress(llvm::raw_ostream &Out,
const std::vector<RelocationRef> &Rels,
uint64_t Offset, uint32_t Disp) {
StringRef Sym;
if (!resolveSymbolName(Rels, Offset, Sym)) {
Out << Sym;
if (Disp > 0)
Out << format(" + 0x%04x", Disp);
} else {
Out << format("0x%04x", Disp);
}
}
static void
printSEHTable(const COFFObjectFile *Obj, uint32_t TableVA, int Count) {
if (Count == 0)
return;
const pe32_header *PE32Header;
if (error(Obj->getPE32Header(PE32Header)))
return;
uint32_t ImageBase = PE32Header->ImageBase;
uintptr_t IntPtr = 0;
if (error(Obj->getVaPtr(TableVA, IntPtr)))
return;
const support::ulittle32_t *P = (const support::ulittle32_t *)IntPtr;
outs() << "SEH Table:";
for (int I = 0; I < Count; ++I)
outs() << format(" 0x%x", P[I] + ImageBase);
outs() << "\n\n";
}
static void printLoadConfiguration(const COFFObjectFile *Obj) {
// Skip if it's not executable.
const pe32_header *PE32Header;
if (error(Obj->getPE32Header(PE32Header)))
return;
if (!PE32Header)
return;
// Currently only x86 is supported
if (Obj->getMachine() != COFF::IMAGE_FILE_MACHINE_I386)
return;
const data_directory *DataDir;
if (error(Obj->getDataDirectory(COFF::LOAD_CONFIG_TABLE, DataDir)))
return;
uintptr_t IntPtr = 0;
if (DataDir->RelativeVirtualAddress == 0)
return;
if (error(Obj->getRvaPtr(DataDir->RelativeVirtualAddress, IntPtr)))
return;
auto *LoadConf = reinterpret_cast<const coff_load_configuration32 *>(IntPtr);
outs() << "Load configuration:"
<< "\n Timestamp: " << LoadConf->TimeDateStamp
<< "\n Major Version: " << LoadConf->MajorVersion
<< "\n Minor Version: " << LoadConf->MinorVersion
<< "\n GlobalFlags Clear: " << LoadConf->GlobalFlagsClear
<< "\n GlobalFlags Set: " << LoadConf->GlobalFlagsSet
<< "\n Critical Section Default Timeout: " << LoadConf->CriticalSectionDefaultTimeout
<< "\n Decommit Free Block Threshold: " << LoadConf->DeCommitFreeBlockThreshold
<< "\n Decommit Total Free Threshold: " << LoadConf->DeCommitTotalFreeThreshold
<< "\n Lock Prefix Table: " << LoadConf->LockPrefixTable
<< "\n Maximum Allocation Size: " << LoadConf->MaximumAllocationSize
<< "\n Virtual Memory Threshold: " << LoadConf->VirtualMemoryThreshold
<< "\n Process Affinity Mask: " << LoadConf->ProcessAffinityMask
<< "\n Process Heap Flags: " << LoadConf->ProcessHeapFlags
<< "\n CSD Version: " << LoadConf->CSDVersion
<< "\n Security Cookie: " << LoadConf->SecurityCookie
<< "\n SEH Table: " << LoadConf->SEHandlerTable
<< "\n SEH Count: " << LoadConf->SEHandlerCount
<< "\n\n";
printSEHTable(Obj, LoadConf->SEHandlerTable, LoadConf->SEHandlerCount);
outs() << "\n";
}
// Prints import tables. The import table is a table containing the list of
// DLL name and symbol names which will be linked by the loader.
static void printImportTables(const COFFObjectFile *Obj) {
import_directory_iterator I = Obj->import_directory_begin();
import_directory_iterator E = Obj->import_directory_end();
if (I == E)
return;
outs() << "The Import Tables:\n";
for (; I != E; I = ++I) {
const import_directory_table_entry *Dir;
StringRef Name;
if (I->getImportTableEntry(Dir)) return;
if (I->getName(Name)) return;
outs() << format(" lookup %08x time %08x fwd %08x name %08x addr %08x\n\n",
static_cast<uint32_t>(Dir->ImportLookupTableRVA),
static_cast<uint32_t>(Dir->TimeDateStamp),
static_cast<uint32_t>(Dir->ForwarderChain),
static_cast<uint32_t>(Dir->NameRVA),
static_cast<uint32_t>(Dir->ImportAddressTableRVA));
outs() << " DLL Name: " << Name << "\n";
outs() << " Hint/Ord Name\n";
const import_lookup_table_entry32 *entry;
if (I->getImportLookupEntry(entry))
return;
for (; entry->data; ++entry) {
if (entry->isOrdinal()) {
outs() << format(" % 6d\n", entry->getOrdinal());
continue;
}
uint16_t Hint;
StringRef Name;
if (Obj->getHintName(entry->getHintNameRVA(), Hint, Name))
return;
outs() << format(" % 6d ", Hint) << Name << "\n";
}
outs() << "\n";
}
}
// Prints export tables. The export table is a table containing the list of
// exported symbol from the DLL.
static void printExportTable(const COFFObjectFile *Obj) {
outs() << "Export Table:\n";
export_directory_iterator I = Obj->export_directory_begin();
export_directory_iterator E = Obj->export_directory_end();
if (I == E)
return;
StringRef DllName;
uint32_t OrdinalBase;
if (I->getDllName(DllName))
return;
if (I->getOrdinalBase(OrdinalBase))
return;
outs() << " DLL name: " << DllName << "\n";
outs() << " Ordinal base: " << OrdinalBase << "\n";
outs() << " Ordinal RVA Name\n";
for (; I != E; I = ++I) {
uint32_t Ordinal;
if (I->getOrdinal(Ordinal))
return;
uint32_t RVA;
if (I->getExportRVA(RVA))
return;
outs() << format(" % 4d %# 8x", Ordinal, RVA);
StringRef Name;
if (I->getSymbolName(Name))
continue;
if (!Name.empty())
outs() << " " << Name;
outs() << "\n";
}
}
// Given the COFF object file, this function returns the relocations for .pdata
// and the pointer to "runtime function" structs.
static bool getPDataSection(const COFFObjectFile *Obj,
std::vector<RelocationRef> &Rels,
const RuntimeFunction *&RFStart, int &NumRFs) {
for (const SectionRef &Section : Obj->sections()) {
StringRef Name;
if (error(Section.getName(Name)))
continue;
if (Name != ".pdata")
continue;
const coff_section *Pdata = Obj->getCOFFSection(Section);
for (const RelocationRef &Reloc : Section.relocations())
Rels.push_back(Reloc);
// Sort relocations by address.
std::sort(Rels.begin(), Rels.end(), RelocAddressLess);
ArrayRef<uint8_t> Contents;
if (error(Obj->getSectionContents(Pdata, Contents)))
continue;
if (Contents.empty())
continue;
RFStart = reinterpret_cast<const RuntimeFunction *>(Contents.data());
NumRFs = Contents.size() / sizeof(RuntimeFunction);
return true;
}
return false;
}
static void printWin64EHUnwindInfo(const Win64EH::UnwindInfo *UI) {
// The casts to int are required in order to output the value as number.
// Without the casts the value would be interpreted as char data (which
// results in garbage output).
outs() << " Version: " << static_cast<int>(UI->getVersion()) << "\n";
outs() << " Flags: " << static_cast<int>(UI->getFlags());
if (UI->getFlags()) {
if (UI->getFlags() & UNW_ExceptionHandler)
outs() << " UNW_ExceptionHandler";
if (UI->getFlags() & UNW_TerminateHandler)
outs() << " UNW_TerminateHandler";
if (UI->getFlags() & UNW_ChainInfo)
outs() << " UNW_ChainInfo";
}
outs() << "\n";
outs() << " Size of prolog: " << static_cast<int>(UI->PrologSize) << "\n";
outs() << " Number of Codes: " << static_cast<int>(UI->NumCodes) << "\n";
// Maybe this should move to output of UOP_SetFPReg?
if (UI->getFrameRegister()) {
outs() << " Frame register: "
<< getUnwindRegisterName(UI->getFrameRegister()) << "\n";
outs() << " Frame offset: " << 16 * UI->getFrameOffset() << "\n";
} else {
outs() << " No frame pointer used\n";
}
if (UI->getFlags() & (UNW_ExceptionHandler | UNW_TerminateHandler)) {
// FIXME: Output exception handler data
} else if (UI->getFlags() & UNW_ChainInfo) {
// FIXME: Output chained unwind info
}
if (UI->NumCodes)
outs() << " Unwind Codes:\n";
printAllUnwindCodes(ArrayRef<UnwindCode>(&UI->UnwindCodes[0], UI->NumCodes));
outs() << "\n";
outs().flush();
}
/// Prints out the given RuntimeFunction struct for x64, assuming that Obj is
/// pointing to an executable file.
static void printRuntimeFunction(const COFFObjectFile *Obj,
const RuntimeFunction &RF) {
if (!RF.StartAddress)
return;
outs() << "Function Table:\n"
<< format(" Start Address: 0x%04x\n",
static_cast<uint32_t>(RF.StartAddress))
<< format(" End Address: 0x%04x\n",
static_cast<uint32_t>(RF.EndAddress))
<< format(" Unwind Info Address: 0x%04x\n",
static_cast<uint32_t>(RF.UnwindInfoOffset));
uintptr_t addr;
if (Obj->getRvaPtr(RF.UnwindInfoOffset, addr))
return;
printWin64EHUnwindInfo(reinterpret_cast<const Win64EH::UnwindInfo *>(addr));
}
/// Prints out the given RuntimeFunction struct for x64, assuming that Obj is
/// pointing to an object file. Unlike executable, fields in RuntimeFunction
/// struct are filled with zeros, but instead there are relocations pointing to
/// them so that the linker will fill targets' RVAs to the fields at link
/// time. This function interprets the relocations to find the data to be used
/// in the resulting executable.
static void printRuntimeFunctionRels(const COFFObjectFile *Obj,
const RuntimeFunction &RF,
uint64_t SectionOffset,
const std::vector<RelocationRef> &Rels) {
outs() << "Function Table:\n";
outs() << " Start Address: ";
printCOFFSymbolAddress(outs(), Rels,
SectionOffset +
/*offsetof(RuntimeFunction, StartAddress)*/ 0,
RF.StartAddress);
outs() << "\n";
outs() << " End Address: ";
printCOFFSymbolAddress(outs(), Rels,
SectionOffset +
/*offsetof(RuntimeFunction, EndAddress)*/ 4,
RF.EndAddress);
outs() << "\n";
outs() << " Unwind Info Address: ";
printCOFFSymbolAddress(outs(), Rels,
SectionOffset +
/*offsetof(RuntimeFunction, UnwindInfoOffset)*/ 8,
RF.UnwindInfoOffset);
outs() << "\n";
ArrayRef<uint8_t> XContents;
uint64_t UnwindInfoOffset = 0;
if (error(getSectionContents(
Obj, Rels, SectionOffset +
/*offsetof(RuntimeFunction, UnwindInfoOffset)*/ 8,
XContents, UnwindInfoOffset)))
return;
if (XContents.empty())
return;
UnwindInfoOffset += RF.UnwindInfoOffset;
if (UnwindInfoOffset > XContents.size())
return;
auto *UI = reinterpret_cast<const Win64EH::UnwindInfo *>(XContents.data() +
UnwindInfoOffset);
printWin64EHUnwindInfo(UI);
}
void llvm::printCOFFUnwindInfo(const COFFObjectFile *Obj) {
if (Obj->getMachine() != COFF::IMAGE_FILE_MACHINE_AMD64) {
errs() << "Unsupported image machine type "
"(currently only AMD64 is supported).\n";
return;
}
std::vector<RelocationRef> Rels;
const RuntimeFunction *RFStart;
int NumRFs;
if (!getPDataSection(Obj, Rels, RFStart, NumRFs))
return;
ArrayRef<RuntimeFunction> RFs(RFStart, NumRFs);
bool IsExecutable = Rels.empty();
if (IsExecutable) {
for (const RuntimeFunction &RF : RFs)
printRuntimeFunction(Obj, RF);
return;
}
for (const RuntimeFunction &RF : RFs) {
uint64_t SectionOffset =
std::distance(RFs.begin(), &RF) * sizeof(RuntimeFunction);
printRuntimeFunctionRels(Obj, RF, SectionOffset, Rels);
}
}
void llvm::printCOFFFileHeader(const object::ObjectFile *Obj) {
const COFFObjectFile *file = dyn_cast<const COFFObjectFile>(Obj);
printLoadConfiguration(file);
printImportTables(file);
printExportTable(file);
}