1 //===- lib/MC/MCSectionCOFF.cpp - COFF Code Section Representation --------===// 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/MCSectionCOFF.h" 11 #include "llvm/MC/MCAsmInfo.h" 12 #include "llvm/MC/MCContext.h" 13 #include "llvm/MC/MCSymbol.h" 14 #include "llvm/Support/raw_ostream.h" 15 using namespace llvm; 16 17 MCSectionCOFF::~MCSectionCOFF() {} // anchor. 18 19 // ShouldOmitSectionDirective - Decides whether a '.section' directive 20 // should be printed before the section name 21 bool MCSectionCOFF::ShouldOmitSectionDirective(StringRef Name, 22 const MCAsmInfo &MAI) const { 23 if (COMDATSymbol) 24 return false; 25 26 // FIXME: Does .section .bss/.data/.text work everywhere?? 27 if (Name == ".text" || Name == ".data" || Name == ".bss") 28 return true; 29 30 return false; 31 } 32 33 void MCSectionCOFF::setSelection(int Selection) const { 34 assert(Selection != 0 && "invalid COMDAT selection type"); 35 this->Selection = Selection; 36 Characteristics |= COFF::IMAGE_SCN_LNK_COMDAT; 37 } 38 39 void MCSectionCOFF::PrintSwitchToSection(const MCAsmInfo &MAI, 40 raw_ostream &OS, 41 const MCExpr *Subsection) const { 42 43 // standard sections don't require the '.section' 44 if (ShouldOmitSectionDirective(SectionName, MAI)) { 45 OS << '\t' << getSectionName() << '\n'; 46 return; 47 } 48 49 OS << "\t.section\t" << getSectionName() << ",\""; 50 if (getCharacteristics() & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA) 51 OS << 'd'; 52 if (getCharacteristics() & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA) 53 OS << 'b'; 54 if (getCharacteristics() & COFF::IMAGE_SCN_MEM_EXECUTE) 55 OS << 'x'; 56 if (getCharacteristics() & COFF::IMAGE_SCN_MEM_WRITE) 57 OS << 'w'; 58 else if (getCharacteristics() & COFF::IMAGE_SCN_MEM_READ) 59 OS << 'r'; 60 else 61 OS << 'y'; 62 if (getCharacteristics() & COFF::IMAGE_SCN_LNK_REMOVE) 63 OS << 'n'; 64 if (getCharacteristics() & COFF::IMAGE_SCN_MEM_SHARED) 65 OS << 's'; 66 OS << '"'; 67 68 if (getCharacteristics() & COFF::IMAGE_SCN_LNK_COMDAT) { 69 OS << ","; 70 switch (Selection) { 71 case COFF::IMAGE_COMDAT_SELECT_NODUPLICATES: 72 OS << "one_only,"; 73 break; 74 case COFF::IMAGE_COMDAT_SELECT_ANY: 75 OS << "discard,"; 76 break; 77 case COFF::IMAGE_COMDAT_SELECT_SAME_SIZE: 78 OS << "same_size,"; 79 break; 80 case COFF::IMAGE_COMDAT_SELECT_EXACT_MATCH: 81 OS << "same_contents,"; 82 break; 83 case COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE: 84 OS << "associative,"; 85 break; 86 case COFF::IMAGE_COMDAT_SELECT_LARGEST: 87 OS << "largest,"; 88 break; 89 case COFF::IMAGE_COMDAT_SELECT_NEWEST: 90 OS << "newest,"; 91 break; 92 default: 93 assert (0 && "unsupported COFF selection type"); 94 break; 95 } 96 assert(COMDATSymbol); 97 OS << *COMDATSymbol; 98 } 99 OS << '\n'; 100 } 101 102 bool MCSectionCOFF::UseCodeAlign() const { 103 return getKind().isText(); 104 } 105 106 bool MCSectionCOFF::isVirtualSection() const { 107 return getCharacteristics() & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA; 108 } 109