1 //===- lib/MC/MCSymbol.cpp - MCSymbol implementation ----------------------===// 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 #include "llvm/MC/MCSymbol.h" 11 #include "llvm/MC/MCAsmInfo.h" 12 #include "llvm/MC/MCContext.h" 13 #include "llvm/MC/MCExpr.h" 14 #include "llvm/Support/Debug.h" 15 #include "llvm/Support/ErrorHandling.h" 16 #include "llvm/Support/raw_ostream.h" 17 using namespace llvm; 18 19 // Sentinel value for the absolute pseudo section. 20 MCSection *MCSymbol::AbsolutePseudoSection = reinterpret_cast<MCSection *>(1); 21 22 void *MCSymbol::operator new(size_t s, const StringMapEntry<bool> *Name, 23 MCContext &Ctx) { 24 // We may need more space for a Name to account for alignment. So allocate 25 // space for the storage type and not the name pointer. 26 size_t Size = s + (Name ? sizeof(NameEntryStorageTy) : 0); 27 28 // For safety, ensure that the alignment of a pointer is enough for an 29 // MCSymbol. This also ensures we don't need padding between the name and 30 // symbol. 31 static_assert(AlignOf<MCSymbol>::Alignment <= 32 AlignOf<NameEntryStorageTy>::Alignment, 33 "Bad alignment of MCSymbol"); 34 void *Storage = Ctx.allocate(Size, alignOf<NameEntryStorageTy>()); 35 NameEntryStorageTy *Start = static_cast<NameEntryStorageTy*>(Storage); 36 NameEntryStorageTy *End = Start + (Name ? 1 : 0); 37 return End; 38 } 39 40 void MCSymbol::setVariableValue(const MCExpr *Value) { 41 assert(!IsUsed && "Cannot set a variable that has already been used."); 42 assert(Value && "Invalid variable value!"); 43 assert((SymbolContents == SymContentsUnset || 44 SymbolContents == SymContentsVariable) && 45 "Cannot give common/offset symbol a variable value"); 46 this->Value = Value; 47 SymbolContents = SymContentsVariable; 48 SectionOrFragment = nullptr; 49 } 50 51 void MCSymbol::print(raw_ostream &OS, const MCAsmInfo *MAI) const { 52 // The name for this MCSymbol is required to be a valid target name. However, 53 // some targets support quoting names with funny characters. If the name 54 // contains a funny character, then print it quoted. 55 StringRef Name = getName(); 56 if (!MAI || MAI->isValidUnquotedName(Name)) { 57 OS << Name; 58 return; 59 } 60 61 if (MAI && !MAI->supportsNameQuoting()) 62 report_fatal_error("Symbol name with unsupported characters"); 63 64 OS << '"'; 65 for (char C : Name) { 66 if (C == '\n') 67 OS << "\\n"; 68 else if (C == '"') 69 OS << "\\\""; 70 else 71 OS << C; 72 } 73 OS << '"'; 74 } 75 76 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP) 77 void MCSymbol::dump() const { dbgs() << *this; } 78 #endif 79