1 //===-- MCAsmInfo.cpp - Asm Info -------------------------------------------==// 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 defines target asm properties related what form asm statements 11 // should take. 12 // 13 //===----------------------------------------------------------------------===// 14 15 #include "llvm/MC/MCAsmInfo.h" 16 #include "llvm/MC/MCContext.h" 17 #include "llvm/MC/MCExpr.h" 18 #include "llvm/MC/MCStreamer.h" 19 #include "llvm/Support/DataTypes.h" 20 #include "llvm/Support/Dwarf.h" 21 #include <cctype> 22 #include <cstring> 23 using namespace llvm; 24 25 MCAsmInfo::MCAsmInfo() { 26 PointerSize = 4; 27 CalleeSaveStackSlotSize = 4; 28 29 IsLittleEndian = true; 30 StackGrowsUp = false; 31 HasSubsectionsViaSymbols = false; 32 HasMachoZeroFillDirective = false; 33 HasMachoTBSSDirective = false; 34 HasStaticCtorDtorReferenceInStaticMode = false; 35 LinkerRequiresNonEmptyDwarfLines = false; 36 MaxInstLength = 4; 37 PCSymbol = "$"; 38 SeparatorString = ";"; 39 CommentColumn = 40; 40 CommentString = "#"; 41 LabelSuffix = ":"; 42 DebugLabelSuffix = ":"; 43 GlobalPrefix = ""; 44 PrivateGlobalPrefix = "."; 45 LinkerPrivateGlobalPrefix = ""; 46 InlineAsmStart = "APP"; 47 InlineAsmEnd = "NO_APP"; 48 Code16Directive = ".code16"; 49 Code32Directive = ".code32"; 50 Code64Directive = ".code64"; 51 AssemblerDialect = 0; 52 AllowQuotesInName = false; 53 AllowNameToStartWithDigit = false; 54 AllowPeriodsInName = true; 55 AllowUTF8 = true; 56 UseDataRegionDirectives = false; 57 ZeroDirective = "\t.zero\t"; 58 AsciiDirective = "\t.ascii\t"; 59 AscizDirective = "\t.asciz\t"; 60 Data8bitsDirective = "\t.byte\t"; 61 Data16bitsDirective = "\t.short\t"; 62 Data32bitsDirective = "\t.long\t"; 63 Data64bitsDirective = "\t.quad\t"; 64 SunStyleELFSectionSwitchSyntax = false; 65 UsesELFSectionDirectiveForBSS = false; 66 AlignDirective = "\t.align\t"; 67 AlignmentIsInBytes = true; 68 TextAlignFillValue = 0; 69 GPRel64Directive = 0; 70 GPRel32Directive = 0; 71 GlobalDirective = "\t.globl\t"; 72 HasSetDirective = true; 73 HasAggressiveSymbolFolding = true; 74 COMMDirectiveAlignmentIsInBytes = true; 75 LCOMMDirectiveAlignmentType = LCOMM::NoAlignment; 76 HasDotTypeDotSizeDirective = true; 77 HasSingleParameterDotFile = true; 78 HasNoDeadStrip = false; 79 HasSymbolResolver = false; 80 WeakRefDirective = 0; 81 WeakDefDirective = 0; 82 LinkOnceDirective = 0; 83 HiddenVisibilityAttr = MCSA_Hidden; 84 HiddenDeclarationVisibilityAttr = MCSA_Hidden; 85 ProtectedVisibilityAttr = MCSA_Protected; 86 HasLEB128 = false; 87 SupportsDebugInformation = false; 88 ExceptionsType = ExceptionHandling::None; 89 DwarfUsesInlineInfoSection = false; 90 DwarfSectionOffsetDirective = 0; 91 DwarfUsesRelocationsAcrossSections = true; 92 DwarfRegNumForCFI = false; 93 HasMicrosoftFastStdCallMangling = false; 94 } 95 96 MCAsmInfo::~MCAsmInfo() { 97 } 98 99 100 unsigned MCAsmInfo::getULEB128Size(unsigned Value) { 101 unsigned Size = 0; 102 do { 103 Value >>= 7; 104 Size += sizeof(int8_t); 105 } while (Value); 106 return Size; 107 } 108 109 unsigned MCAsmInfo::getSLEB128Size(int Value) { 110 unsigned Size = 0; 111 int Sign = Value >> (8 * sizeof(Value) - 1); 112 bool IsMore; 113 114 do { 115 unsigned Byte = Value & 0x7f; 116 Value >>= 7; 117 IsMore = Value != Sign || ((Byte ^ Sign) & 0x40) != 0; 118 Size += sizeof(int8_t); 119 } while (IsMore); 120 return Size; 121 } 122 123 const MCExpr * 124 MCAsmInfo::getExprForPersonalitySymbol(const MCSymbol *Sym, 125 unsigned Encoding, 126 MCStreamer &Streamer) const { 127 return getExprForFDESymbol(Sym, Encoding, Streamer); 128 } 129 130 const MCExpr * 131 MCAsmInfo::getExprForFDESymbol(const MCSymbol *Sym, 132 unsigned Encoding, 133 MCStreamer &Streamer) const { 134 if (!(Encoding & dwarf::DW_EH_PE_pcrel)) 135 return MCSymbolRefExpr::Create(Sym, Streamer.getContext()); 136 137 MCContext &Context = Streamer.getContext(); 138 const MCExpr *Res = MCSymbolRefExpr::Create(Sym, Context); 139 MCSymbol *PCSym = Context.CreateTempSymbol(); 140 Streamer.EmitLabel(PCSym); 141 const MCExpr *PC = MCSymbolRefExpr::Create(PCSym, Context); 142 return MCBinaryExpr::CreateSub(Res, PC, Context); 143 } 144