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 ~MCSectionCOFF()17MCSectionCOFF::~MCSectionCOFF() {} // anchor. 18 19 // ShouldOmitSectionDirective - Decides whether a '.section' directive 20 // should be printed before the section name ShouldOmitSectionDirective(StringRef Name,const MCAsmInfo & MAI) const21bool MCSectionCOFF::ShouldOmitSectionDirective(StringRef Name, 22 const MCAsmInfo &MAI) const { 23 24 // FIXME: Does .section .bss/.data/.text work everywhere?? 25 if (Name == ".text" || Name == ".data" || Name == ".bss") 26 return true; 27 28 return false; 29 } 30 PrintSwitchToSection(const MCAsmInfo & MAI,raw_ostream & OS) const31void MCSectionCOFF::PrintSwitchToSection(const MCAsmInfo &MAI, 32 raw_ostream &OS) const { 33 34 // standard sections don't require the '.section' 35 if (ShouldOmitSectionDirective(SectionName, MAI)) { 36 OS << '\t' << getSectionName() << '\n'; 37 return; 38 } 39 40 OS << "\t.section\t" << getSectionName() << ",\""; 41 if (getKind().isText()) 42 OS << 'x'; 43 if (getKind().isWriteable()) 44 OS << 'w'; 45 else 46 OS << 'r'; 47 if (getCharacteristics() & COFF::IMAGE_SCN_MEM_DISCARDABLE) 48 OS << 'n'; 49 OS << "\"\n"; 50 51 if (getCharacteristics() & COFF::IMAGE_SCN_LNK_COMDAT) { 52 switch (Selection) { 53 case COFF::IMAGE_COMDAT_SELECT_NODUPLICATES: 54 OS << "\t.linkonce one_only\n"; 55 break; 56 case COFF::IMAGE_COMDAT_SELECT_ANY: 57 OS << "\t.linkonce discard\n"; 58 break; 59 case COFF::IMAGE_COMDAT_SELECT_SAME_SIZE: 60 OS << "\t.linkonce same_size\n"; 61 break; 62 case COFF::IMAGE_COMDAT_SELECT_EXACT_MATCH: 63 OS << "\t.linkonce same_contents\n"; 64 break; 65 //NOTE: as of binutils 2.20, there is no way to specifiy select largest 66 // with the .linkonce directive. For now, we treat it as an invalid 67 // comdat selection value. 68 case COFF::IMAGE_COMDAT_SELECT_LARGEST: 69 // OS << "\t.linkonce largest\n"; 70 // break; 71 default: 72 assert (0 && "unsupported COFF selection type"); 73 break; 74 } 75 } 76 } 77 UseCodeAlign() const78bool MCSectionCOFF::UseCodeAlign() const { 79 return getKind().isText(); 80 } 81 isVirtualSection() const82bool MCSectionCOFF::isVirtualSection() const { 83 return getCharacteristics() & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA; 84 } 85