diff options
Diffstat (limited to 'contrib/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp')
-rw-r--r-- | contrib/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp | 138 |
1 files changed, 138 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..68be2ee --- /dev/null +++ b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfCFIException.cpp @@ -0,0 +1,138 @@ +//===-- 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/Module.h" +#include "llvm/CodeGen/AsmPrinter.h" +#include "llvm/CodeGen/MachineModuleInfo.h" +#include "llvm/CodeGen/MachineFrameInfo.h" +#include "llvm/CodeGen/MachineFunction.h" +#include "llvm/CodeGen/MachineLocation.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/Target/Mangler.h" +#include "llvm/Target/TargetData.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" +#include "llvm/Support/Dwarf.h" +#include "llvm/Support/FormattedStream.h" +#include "llvm/ADT/SmallString.h" +#include "llvm/ADT/StringExtras.h" +#include "llvm/ADT/Twine.h" +using namespace llvm; + +DwarfCFIException::DwarfCFIException(AsmPrinter *A) + : DwarfException(A), + shouldEmitTable(false), shouldEmitMoves(false), shouldEmitTableModule(false) + {} + +DwarfCFIException::~DwarfCFIException() {} + +/// EndModule - Emit all exception information that should come after the +/// content. +void DwarfCFIException::EndModule() { + if (!Asm->MAI->isExceptionHandlingDwarf()) + return; + + if (!shouldEmitTableModule) + return; + + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); + unsigned PerEncoding = TLOF.getPersonalityEncoding(); + + // Begin eh frame section. + Asm->OutStreamer.SwitchSection(TLOF.getEHFrameSection()); + + // 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) { + Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("personality", i)); + Asm->EmitReference(Personalities[i], PerEncoding); + } +} + +/// BeginFunction - Gather pre-function exception information. Assumes it's +/// being emitted immediately after the function entry point. +void DwarfCFIException::BeginFunction(const MachineFunction *MF) { + shouldEmitTable = shouldEmitMoves = false; + + // If any landing pads survive, we need an EH table. + shouldEmitTable = !MMI->getLandingPads().empty(); + + // See if we need frame move info. + shouldEmitMoves = + !Asm->MF->getFunction()->doesNotThrow() || UnwindTablesMandatory; + + if (shouldEmitMoves || shouldEmitTable) + // Assumes in correct section after the entry point. + Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_begin", + Asm->getFunctionNumber())); + + shouldEmitTableModule |= shouldEmitTable; + + if (shouldEmitMoves) { + const TargetFrameLowering *TFL = Asm->TM.getFrameLowering(); + Asm->OutStreamer.EmitCFIStartProc(); + + // Indicate locations of general callee saved registers in frame. + std::vector<MachineMove> Moves; + TFL->getInitialFrameState(Moves); + Asm->EmitCFIFrameMoves(Moves); + Asm->EmitCFIFrameMoves(MMI->getFrameMoves()); + } + + if (!shouldEmitTable) + return; + + const TargetLoweringObjectFile &TLOF = Asm->getObjFileLowering(); + + // Provide LSDA information. + unsigned LSDAEncoding = TLOF.getLSDAEncoding(); + if (LSDAEncoding != dwarf::DW_EH_PE_omit) + Asm->OutStreamer.EmitCFILsda(Asm->GetTempSymbol("exception", + Asm->getFunctionNumber()), + LSDAEncoding); + + // Indicate personality routine, if any. + unsigned PerEncoding = TLOF.getPersonalityEncoding(); + if (PerEncoding != dwarf::DW_EH_PE_omit && + MMI->getPersonalities()[MMI->getPersonalityIndex()]) + Asm->OutStreamer.EmitCFIPersonality(Asm->GetTempSymbol("personality", + MMI->getPersonalityIndex()), + PerEncoding); +} + +/// EndFunction - Gather and emit post-function exception information. +/// +void DwarfCFIException::EndFunction() { + if (!shouldEmitMoves && !shouldEmitTable) return; + + if (shouldEmitMoves) + Asm->OutStreamer.EmitCFIEndProc(); + + Asm->OutStreamer.EmitLabel(Asm->GetTempSymbol("eh_func_end", + Asm->getFunctionNumber())); + + // Map all labels and get rid of any dead landing pads. + MMI->TidyLandingPads(); + + if (shouldEmitTable) + EmitExceptionTable(); +} |