From eef7b6219ebe5d0ded0be4adb3003055fa8a63c4 Mon Sep 17 00:00:00 2001 From: "Michael J. Spencer" Date: Wed, 5 Dec 2012 20:12:35 +0000 Subject: [PATCH] Add dump of Win64 EH unwind data. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The new command line option -unwind-info dumps the Win64 EH unwind data to the console. This is a nice feature if you need to debug generated EH data (e.g. from LLVM). Includes a test case. Initial patch by João Matos, extensions and rework by Kai Nacke. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169415 91177308-0d34-0410-b5e6-96231b3b80d8 --- test/tools/llvm-objdump/win64-unwind-data.s | 106 ++++++ tools/llvm-objdump/CMakeLists.txt | 1 + tools/llvm-objdump/COFFDump.cpp | 355 ++++++++++++++++++++ tools/llvm-objdump/llvm-objdump.cpp | 29 +- tools/llvm-objdump/llvm-objdump.h | 9 + 5 files changed, 497 insertions(+), 3 deletions(-) create mode 100644 test/tools/llvm-objdump/win64-unwind-data.s create mode 100644 tools/llvm-objdump/COFFDump.cpp diff --git a/test/tools/llvm-objdump/win64-unwind-data.s b/test/tools/llvm-objdump/win64-unwind-data.s new file mode 100644 index 00000000000..1e4c7428ce3 --- /dev/null +++ b/test/tools/llvm-objdump/win64-unwind-data.s @@ -0,0 +1,106 @@ +// This test checks that the unwind data is dumped by llvm-objdump. +// RUN: llvm-mc -triple x86_64-pc-win32 -filetype=obj %s | llvm-objdump -u - | FileCheck %s + +// CHECK: Unwind info: +// CHECK: Function Table: +// CHECK-NEXT: Start Address: .text +// CHECK-NEXT: End Address: .text + 0x001b +// CHECK-NEXT: Unwind Info Address: .xdata +// CHECK-NEXT: Version: 1 +// CHECK-NEXT: Flags: 1 UNW_ExceptionHandler +// CHECK-NEXT: Size of prolog: 18 +// CHECK-NEXT: Number of Codes: 8 +// CHECK-NEXT: Frame register: RBX +// CHECK-NEXT: Frame offset: 0 +// CHECK-NEXT: Unwind Codes: +// CHECK-NEXT: 0x00: UOP_SetFPReg +// CHECK-NEXT: 0x0f: UOP_PushNonVol RBX +// CHECK-NEXT: 0x0e: UOP_SaveXMM128 XMM8 [0x0000] +// CHECK-NEXT: 0x09: UOP_SaveNonVol RSI [0x0010] +// CHECK-NEXT: 0x04: UOP_AllocSmall 24 +// CHECK-NEXT: 0x00: UOP_PushMachFrame w/o error code +// CHECK: Function Table: +// CHECK-NEXT: Start Address: .text + 0x0012 +// CHECK-NEXT: End Address: .text + 0x0012 +// CHECK-NEXT: Unwind Info Address: .xdata + 0x001c +// CHECK-NEXT: Version: 1 +// CHECK-NEXT: Flags: 4 UNW_ChainInfo +// CHECK-NEXT: Size of prolog: 0 +// CHECK-NEXT: Number of Codes: 0 +// CHECK-NEXT: No frame pointer used +// CHECK: Function Table: +// CHECK-NEXT: Start Address: .text + 0x001b +// CHECK-NEXT: End Address: .text + 0x001c +// CHECK-NEXT: Unwind Info Address: .xdata + 0x002c +// CHECK-NEXT: Version: 1 +// CHECK-NEXT: Flags: 0 +// CHECK-NEXT: Size of prolog: 0 +// CHECK-NEXT: Number of Codes: 0 +// CHECK-NEXT: No frame pointer used +// CHECK: Function Table: +// CHECK-NEXT: Start Address: .text + 0x001c +// CHECK-NEXT: End Address: .text + 0x0039 +// CHECK-NEXT: Unwind Info Address: .xdata + 0x0034 +// CHECK-NEXT: Version: 1 +// CHECK-NEXT: Flags: 0 +// CHECK-NEXT: Size of prolog: 14 +// CHECK-NEXT: Number of Codes: 6 +// CHECK-NEXT: No frame pointer used +// CHECK-NEXT: Unwind Codes: +// CHECK-NEXT: 0x0e: UOP_AllocLarge 8454128 +// CHECK-NEXT: 0x07: UOP_AllocLarge 8190 +// CHECK-NEXT: 0x00: UOP_PushMachFrame w/o error code + + .text + .globl func + .def func; .scl 2; .type 32; .endef + .seh_proc func +func: + .seh_pushframe @code + subq $24, %rsp + .seh_stackalloc 24 + movq %rsi, 16(%rsp) + .seh_savereg %rsi, 16 + movups %xmm8, (%rsp) + .seh_savexmm %xmm8, 0 + pushq %rbx + .seh_pushreg 3 + mov %rsp, %rbx + .seh_setframe 3, 0 + .seh_endprologue + .seh_handler __C_specific_handler, @except + .seh_handlerdata + .long 0 + .text + .seh_startchained + .seh_endprologue + .seh_endchained + lea (%rbx), %rsp + pop %rbx + addq $24, %rsp + ret + .seh_endproc + +// Test emission of small functions. + .globl smallFunc + .def smallFunc; .scl 2; .type 32; .endef + .seh_proc smallFunc +smallFunc: + ret + .seh_endproc + +// Function with big stack allocation. + .globl smallFunc + .def allocFunc; .scl 2; .type 32; .endef + .seh_proc smallFunc +allocFunc: + .seh_pushframe @code + subq $65520, %rsp + .seh_stackalloc 65520 + sub $8454128, %rsp + .seh_stackalloc 8454128 + .seh_endprologue + add $8454128, %rsp + addq $65520, %rsp + ret + .seh_endproc diff --git a/tools/llvm-objdump/CMakeLists.txt b/tools/llvm-objdump/CMakeLists.txt index f3b2e1fe419..5001435e83d 100644 --- a/tools/llvm-objdump/CMakeLists.txt +++ b/tools/llvm-objdump/CMakeLists.txt @@ -9,6 +9,7 @@ set(LLVM_LINK_COMPONENTS add_llvm_tool(llvm-objdump llvm-objdump.cpp + COFFDump.cpp MachODump.cpp MCFunction.cpp ) diff --git a/tools/llvm-objdump/COFFDump.cpp b/tools/llvm-objdump/COFFDump.cpp new file mode 100644 index 00000000000..ed4d1c3344f --- /dev/null +++ b/tools/llvm-objdump/COFFDump.cpp @@ -0,0 +1,355 @@ +//===-- 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 decribed 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/raw_ostream.h" +#include "llvm/Support/system_error.h" +#include "llvm/Support/Win64EH.h" +#include +#include + +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 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(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(UCs[2].FrameOffset) << 16)); + break; + case UOP_SaveXMM128: + outs() << " XMM" << static_cast(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(UCs[2].FrameOffset) << 16)); + break; + case UOP_PushMachFrame: + outs() << " " << (UCs[0].getOpInfo() ? "w/o" : "w") + << " error code"; + break; + } + outs() << "\n"; +} + +static void printAllUnwindCodes(ArrayRef 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(I, E)); + I += UsedSlots; + } +} + +// Given a symbol sym this functions returns the address and section of it. +static error_code resolveSectionAndAddress(const COFFObjectFile *Obj, + const SymbolRef &Sym, + const coff_section *&ResolvedSection, + uint64_t &ResolvedAddr) { + if (error_code ec = Sym.getAddress(ResolvedAddr)) return ec; + section_iterator iter(Obj->begin_sections()); + if (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 error_code resolveSymbol(const std::vector &Rels, + uint64_t Offset, SymbolRef &Sym) { + for (std::vector::const_iterator I = Rels.begin(), + E = Rels.end(); + I != E; ++I) { + uint64_t Ofs; + if (error_code ec = I->getOffset(Ofs)) return ec; + if (Ofs == Offset) { + if (error_code ec = I->getSymbol(Sym)) return ec; + break; + } + } + return object_error::success; +} + +// 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 error_code getSectionContents(const COFFObjectFile *Obj, + const std::vector &Rels, + uint64_t Offset, + ArrayRef &Contents, + uint64_t &Addr) { + SymbolRef Sym; + if (error_code ec = resolveSymbol(Rels, Offset, Sym)) return ec; + const coff_section *Section; + if (error_code ec = resolveSectionAndAddress(Obj, Sym, Section, Addr)) + return ec; + if (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 error_code resolveSymbolName(const std::vector &Rels, + uint64_t Offset, StringRef &Name) { + SymbolRef Sym; + if (error_code ec = resolveSymbol(Rels, Offset, Sym)) return ec; + if (error_code ec = Sym.getName(Name)) return ec; + return object_error::success; +} + +static void printCOFFSymbolAddress(llvm::raw_ostream &Out, + const std::vector &Rels, + uint64_t Offset, uint32_t Disp) { + StringRef Sym; + if (error_code ec = resolveSymbolName(Rels, Offset, Sym)) { + error(ec); + return ; + } + Out << Sym; + if (Disp > 0) + Out << format(" + 0x%04x", Disp); +} + +void llvm::printCOFFUnwindInfo(const COFFObjectFile *Obj) { + const coff_file_header *Header; + if (error(Obj->getHeader(Header))) return; + + if (Header->Machine != COFF::IMAGE_FILE_MACHINE_AMD64) { + errs() << "Unsupported image machine type " + "(currently only AMD64 is supported).\n"; + return; + } + + const coff_section *Pdata = 0; + + error_code ec; + for (section_iterator SI = Obj->begin_sections(), + SE = Obj->end_sections(); + SI != SE; SI.increment(ec)) { + if (error(ec)) return; + + StringRef Name; + if (error(SI->getName(Name))) continue; + + if (Name != ".pdata") continue; + + Pdata = Obj->getCOFFSection(SI); + std::vector Rels; + for (relocation_iterator RI = SI->begin_relocations(), + RE = SI->end_relocations(); + RI != RE; RI.increment(ec)) { + if (error(ec)) break; + Rels.push_back(*RI); + } + + // Sort relocations by address. + std::sort(Rels.begin(), Rels.end(), RelocAddressLess); + + ArrayRef Contents; + if (error(Obj->getSectionContents(Pdata, Contents))) continue; + if (Contents.empty()) continue; + + ArrayRef RFs( + reinterpret_cast(Contents.data()), + Contents.size() / sizeof(RuntimeFunction)); + for (const RuntimeFunction *I = RFs.begin(), *E = RFs.end(); I < E; ++I) { + const uint64_t SectionOffset = std::distance(RFs.begin(), I) + * sizeof(RuntimeFunction); + + outs() << "Function Table:\n"; + + outs() << " Start Address: "; + printCOFFSymbolAddress(outs(), Rels, SectionOffset + + offsetof(RuntimeFunction, StartAddress), + I->StartAddress); + outs() << "\n"; + + outs() << " End Address: "; + printCOFFSymbolAddress(outs(), Rels, SectionOffset + + offsetof(RuntimeFunction, EndAddress), + I->EndAddress); + outs() << "\n"; + + outs() << " Unwind Info Address: "; + printCOFFSymbolAddress(outs(), Rels, SectionOffset + + offsetof(RuntimeFunction, UnwindInfoOffset), + I->UnwindInfoOffset); + outs() << "\n"; + + ArrayRef XContents; + uint64_t UnwindInfoOffset = 0; + if (error(getSectionContents(Obj, Rels, SectionOffset + + offsetof(RuntimeFunction, UnwindInfoOffset), + XContents, UnwindInfoOffset))) continue; + if (XContents.empty()) continue; + + UnwindInfoOffset += I->UnwindInfoOffset; + if (UnwindInfoOffset > XContents.size()) continue; + + const Win64EH::UnwindInfo *UI = + reinterpret_cast + (XContents.data() + UnwindInfoOffset); + + // 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(UI->getVersion()) << "\n"; + outs() << " Flags: " << static_cast(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(UI->PrologSize) << "\n"; + outs() << " Number of Codes: " + << static_cast(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(&UI->UnwindCodes[0], + UI->NumCodes)); + + outs() << "\n\n"; + outs().flush(); + } + } +} diff --git a/tools/llvm-objdump/llvm-objdump.cpp b/tools/llvm-objdump/llvm-objdump.cpp index f1749f031b3..2838a2a2b30 100644 --- a/tools/llvm-objdump/llvm-objdump.cpp +++ b/tools/llvm-objdump/llvm-objdump.cpp @@ -104,9 +104,16 @@ static cl::opt NoShowRawInsn("no-show-raw-insn", cl::desc("When disassembling instructions, " "do not print the instruction bytes.")); +static cl::opt +UnwindInfo("unwind-info", cl::desc("Display unwind information")); + +static cl::alias +UnwindInfoShort("u", cl::desc("Alias for --unwind-info"), + cl::aliasopt(UnwindInfo)); + static StringRef ToolName; -static bool error(error_code ec) { +bool llvm::error(error_code ec) { if (!ec) return false; outs() << ToolName << ": error reading file: " << ec.message() << ".\n"; @@ -165,7 +172,7 @@ void llvm::DumpBytes(StringRef bytes) { outs() << output; } -static bool RelocAddressLess(RelocationRef a, RelocationRef b) { +bool llvm::RelocAddressLess(RelocationRef a, RelocationRef b) { uint64_t a_addr, b_addr; if (error(a.getAddress(a_addr))) return false; if (error(b.getAddress(b_addr))) return false; @@ -573,6 +580,19 @@ static void PrintSymbolTable(const ObjectFile *o) { } } +static void PrintUnwindInfo(const ObjectFile *o) { + outs() << "Unwind info:\n\n"; + + if (const COFFObjectFile *coff = dyn_cast(o)) { + printCOFFUnwindInfo(coff); + } else { + // TODO: Extract DWARF dump tool to objdump. + errs() << "This operation is only currently supported " + "for COFF object files.\n"; + return; + } +} + static void DumpObject(const ObjectFile *o) { outs() << '\n'; outs() << o->getFileName() @@ -588,6 +608,8 @@ static void DumpObject(const ObjectFile *o) { PrintSectionContents(o); if (SymbolTable) PrintSymbolTable(o); + if (UnwindInfo) + PrintUnwindInfo(o); } /// @brief Dump each object file in \a a; @@ -666,7 +688,8 @@ int main(int argc, char **argv) { && !Relocations && !SectionHeaders && !SectionContents - && !SymbolTable) { + && !SymbolTable + && !UnwindInfo) { cl::PrintHelpMessage(); return 2; } diff --git a/tools/llvm-objdump/llvm-objdump.h b/tools/llvm-objdump/llvm-objdump.h index aa71b77c8ab..9f5a8c3db97 100644 --- a/tools/llvm-objdump/llvm-objdump.h +++ b/tools/llvm-objdump/llvm-objdump.h @@ -17,12 +17,21 @@ namespace llvm { +namespace object { + class COFFObjectFile; + class RelocationRef; +} +class error_code; + extern cl::opt TripleName; extern cl::opt ArchName; // Various helper functions. +bool error(error_code ec); +bool RelocAddressLess(object::RelocationRef a, object::RelocationRef b); void DumpBytes(StringRef bytes); void DisassembleInputMachO(StringRef Filename); +void printCOFFUnwindInfo(const object::COFFObjectFile* o); class StringRefMemoryObject : public MemoryObject { virtual void anchor();