diff options
Diffstat (limited to 'contrib/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp')
-rw-r--r-- | contrib/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp new file mode 100644 index 0000000..0dc52da --- /dev/null +++ b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp @@ -0,0 +1,154 @@ +//===-- CodeGen/AsmPrinter/DwarfException.cpp - Dwarf Exception Impl ------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This file contains support for writing DWARF exception info into asm files. +// +//===----------------------------------------------------------------------===// + +#include "DwarfException.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/StringExtras.h" +#include "llvm/ADT/Twine.h" +#include "llvm/CodeGen/AsmPrinter.h" +#include "llvm/CodeGen/MachineFrameInfo.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/CodeGen/MachineModuleInfo.h" +#include "llvm/IR/DataLayout.h" +#include "llvm/IR/Mangler.h" +#include "llvm/IR/Module.h" +#include "llvm/MC/MCAsmInfo.h" +#include "llvm/MC/MCContext.h" +#include "llvm/MC/MCExpr.h" +#include "llvm/MC/MCSection.h" +#include "llvm/MC/MCStreamer.h" +#include "llvm/MC/MCSymbol.h" +#include "llvm/MC/MachineLocation.h" +#include "llvm/Support/Dwarf.h" +#include "llvm/Support/ErrorHandling.h" +#include "llvm/Support/FormattedStream.h" +#include "llvm/Target/TargetFrameLowering.h" +#include "llvm/Target/TargetLoweringObjectFile.h" +#include "llvm/Target/TargetMachine.h" +#include "llvm/Target/TargetOptions.h" +#include "llvm/Target/TargetRegisterInfo.h" +using namespace llvm; + +DwarfCFIException::DwarfCFIException(AsmPrinter *A) + : EHStreamer(A), shouldEmitPersonality(false), shouldEmitLSDA(false), + shouldEmitMoves(false), moveTypeModule(AsmPrinter::CFI_M_None) {} + +DwarfCFIException::~DwarfCFIException() {} + +/// endModule - Emit all exception information that should come after the +/// content. +void DwarfCFIException::endModule() { + if (moveTypeModule == AsmPrinter::CFI_M_Debug) + Asm->OutStreamer.EmitCFISections(false, true); + + if (!Asm->MAI->usesItaniumLSDAForExceptions()) + return; + + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); + + unsigned PerEncoding = TLOF.getPersonalityEncoding(); + + if ((PerEncoding & 0x80) != dwarf::DW_EH_PE_indirect) + return; + + // Emit references to all used personality functions + const std::vector<const Function*> &Personalities = MMI->getPersonalities(); + for (size_t i = 0, e = Personalities.size(); i != e; ++i) { + if (!Personalities[i]) + continue; + MCSymbol *Sym = Asm->getSymbol(Personalities[i]); + TLOF.emitPersonalityValue(Asm->OutStreamer, Asm->TM, Sym); + } +} + +/// beginFunction - Gather pre-function exception information. Assumes it's +/// being emitted immediately after the function entry point. +void DwarfCFIException::beginFunction(const MachineFunction *MF) { + shouldEmitMoves = shouldEmitPersonality = shouldEmitLSDA = false; + + // If any landing pads survive, we need an EH table. + bool hasLandingPads = !MMI->getLandingPads().empty(); + + // See if we need frame move info. + AsmPrinter::CFIMoveType MoveType = Asm->needsCFIMoves(); + if (MoveType == AsmPrinter::CFI_M_EH || + (MoveType == AsmPrinter::CFI_M_Debug && + moveTypeModule == AsmPrinter::CFI_M_None)) + moveTypeModule = MoveType; + + shouldEmitMoves = MoveType != AsmPrinter::CFI_M_None; + + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); + unsigned PerEncoding = TLOF.getPersonalityEncoding(); + const Function *Per = MMI->getPersonalities()[MMI->getPersonalityIndex()]; + + shouldEmitPersonality = hasLandingPads && + PerEncoding != dwarf::DW_EH_PE_omit && Per; + + unsigned LSDAEncoding = TLOF.getLSDAEncoding(); + shouldEmitLSDA = shouldEmitPersonality && + LSDAEncoding != dwarf::DW_EH_PE_omit; + + if (!shouldEmitPersonality && !shouldEmitMoves) + return; + + Asm->OutStreamer.EmitCFIStartProc(/*IsSimple=*/false); + + // Indicate personality routine, if any. + if (!shouldEmitPersonality) + return; + + const MCSymbol *Sym = + TLOF.getCFIPersonalitySymbol(Per, *Asm->Mang, Asm->TM, MMI); + Asm->OutStreamer.EmitCFIPersonality(Sym, PerEncoding); + + MCSymbol *EHBegin = + Asm->GetTempSymbol("eh_func_begin", Asm->getFunctionNumber()); + if (Asm->MAI->useAssignmentForEHBegin()) { + MCContext &Ctx = Asm->OutContext; + MCSymbol *CurPos = Ctx.CreateTempSymbol(); + Asm->OutStreamer.EmitLabel(CurPos); + Asm->OutStreamer.EmitAssignment(EHBegin, + MCSymbolRefExpr::Create(CurPos, Ctx)); + } else { + Asm->OutStreamer.EmitLabel(EHBegin); + } + + // Provide LSDA information. + if (!shouldEmitLSDA) + return; + + Asm->OutStreamer.EmitCFILsda(Asm->GetTempSymbol("exception", + Asm->getFunctionNumber()), + LSDAEncoding); +} + +/// endFunction - Gather and emit post-function exception information. +/// +void DwarfCFIException::endFunction(const MachineFunction *) { + if (!shouldEmitPersonality && !shouldEmitMoves) + return; + + Asm->OutStreamer.EmitCFIEndProc(); + + if (!shouldEmitPersonality) + return; + + Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_end", + Asm->getFunctionNumber())); + + // Map all labels and get rid of any dead landing pads. + MMI->TidyLandingPads(); + + emitExceptionTable(); +} |