1 //===-- CodeGen/AsmPrinter/ARMException.cpp - ARM EHABI Exception Impl ----===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file contains support for writing DWARF exception info into asm files. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "DwarfException.h" 15 #include "llvm/ADT/SmallString.h" 16 #include "llvm/ADT/StringExtras.h" 17 #include "llvm/ADT/Twine.h" 18 #include "llvm/CodeGen/AsmPrinter.h" 19 #include "llvm/CodeGen/MachineFrameInfo.h" 20 #include "llvm/CodeGen/MachineFunction.h" 21 #include "llvm/CodeGen/MachineModuleInfo.h" 22 #include "llvm/IR/DataLayout.h" 23 #include "llvm/IR/Mangler.h" 24 #include "llvm/IR/Module.h" 25 #include "llvm/MC/MCAsmInfo.h" 26 #include "llvm/MC/MCContext.h" 27 #include "llvm/MC/MCExpr.h" 28 #include "llvm/MC/MCSection.h" 29 #include "llvm/MC/MCStreamer.h" 30 #include "llvm/MC/MCSymbol.h" 31 #include "llvm/Support/CommandLine.h" 32 #include "llvm/Support/Dwarf.h" 33 #include "llvm/Support/FormattedStream.h" 34 #include "llvm/Target/TargetFrameLowering.h" 35 #include "llvm/Target/TargetOptions.h" 36 #include "llvm/Target/TargetRegisterInfo.h" 37 using namespace llvm; 38 ARMException(AsmPrinter * A)39ARMException::ARMException(AsmPrinter *A) : DwarfCFIExceptionBase(A) {} 40 ~ARMException()41ARMException::~ARMException() {} 42 getTargetStreamer()43ARMTargetStreamer &ARMException::getTargetStreamer() { 44 MCTargetStreamer &TS = *Asm->OutStreamer.getTargetStreamer(); 45 return static_cast<ARMTargetStreamer &>(TS); 46 } 47 48 /// endModule - Emit all exception information that should come after the 49 /// content. endModule()50void ARMException::endModule() { 51 if (shouldEmitCFI) 52 Asm->OutStreamer.EmitCFISections(false, true); 53 } 54 beginFunction(const MachineFunction * MF)55void ARMException::beginFunction(const MachineFunction *MF) { 56 if (Asm->MAI->getExceptionHandlingType() == ExceptionHandling::ARM) 57 getTargetStreamer().emitFnStart(); 58 // See if we need call frame info. 59 AsmPrinter::CFIMoveType MoveType = Asm->needsCFIMoves(); 60 assert(MoveType != AsmPrinter::CFI_M_EH && 61 "non-EH CFI not yet supported in prologue with EHABI lowering"); 62 if (MoveType == AsmPrinter::CFI_M_Debug) { 63 shouldEmitCFI = true; 64 Asm->OutStreamer.EmitCFIStartProc(false); 65 } 66 } 67 68 /// endFunction - Gather and emit post-function exception information. 69 /// endFunction(const MachineFunction * MF)70void ARMException::endFunction(const MachineFunction *MF) { 71 ARMTargetStreamer &ATS = getTargetStreamer(); 72 if (!Asm->MF->getFunction()->needsUnwindTableEntry() && 73 MMI->getLandingPads().empty()) 74 ATS.emitCantUnwind(); 75 else { 76 if (!MMI->getLandingPads().empty()) { 77 // Emit references to personality. 78 if (const Function *Personality = MMI->getPersonality()) { 79 MCSymbol *PerSym = Asm->getSymbol(Personality); 80 Asm->OutStreamer.EmitSymbolAttribute(PerSym, MCSA_Global); 81 ATS.emitPersonality(PerSym); 82 } 83 84 // Emit .handlerdata directive. 85 ATS.emitHandlerData(); 86 87 // Emit actual exception table 88 emitExceptionTable(); 89 } 90 } 91 92 if (Asm->MAI->getExceptionHandlingType() == ExceptionHandling::ARM) 93 ATS.emitFnEnd(); 94 } 95 emitTypeInfos(unsigned TTypeEncoding)96void ARMException::emitTypeInfos(unsigned TTypeEncoding) { 97 const std::vector<const GlobalValue *> &TypeInfos = MMI->getTypeInfos(); 98 const std::vector<unsigned> &FilterIds = MMI->getFilterIds(); 99 100 bool VerboseAsm = Asm->OutStreamer.isVerboseAsm(); 101 102 int Entry = 0; 103 // Emit the Catch TypeInfos. 104 if (VerboseAsm && !TypeInfos.empty()) { 105 Asm->OutStreamer.AddComment(">> Catch TypeInfos <<"); 106 Asm->OutStreamer.AddBlankLine(); 107 Entry = TypeInfos.size(); 108 } 109 110 for (std::vector<const GlobalValue *>::const_reverse_iterator 111 I = TypeInfos.rbegin(), E = TypeInfos.rend(); I != E; ++I) { 112 const GlobalValue *GV = *I; 113 if (VerboseAsm) 114 Asm->OutStreamer.AddComment("TypeInfo " + Twine(Entry--)); 115 Asm->EmitTTypeReference(GV, TTypeEncoding); 116 } 117 118 // Emit the Exception Specifications. 119 if (VerboseAsm && !FilterIds.empty()) { 120 Asm->OutStreamer.AddComment(">> Filter TypeInfos <<"); 121 Asm->OutStreamer.AddBlankLine(); 122 Entry = 0; 123 } 124 for (std::vector<unsigned>::const_iterator 125 I = FilterIds.begin(), E = FilterIds.end(); I < E; ++I) { 126 unsigned TypeID = *I; 127 if (VerboseAsm) { 128 --Entry; 129 if (TypeID != 0) 130 Asm->OutStreamer.AddComment("FilterInfo " + Twine(Entry)); 131 } 132 133 Asm->EmitTTypeReference((TypeID == 0 ? nullptr : TypeInfos[TypeID - 1]), 134 TTypeEncoding); 135 } 136 } 137