MCSectionCOFF.cpp revision cd81d94322a39503e4a3e87b6ee03d4fcb3465fb
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" 15using namespace llvm; 16 17MCSectionCOFF::~MCSectionCOFF() {} // anchor. 18 19// ShouldOmitSectionDirective - Decides whether a '.section' directive 20// should be printed before the section name 21bool 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 33void 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 39void 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 (getKind().isText()) 51 OS << 'x'; 52 else if (getKind().isBSS()) 53 OS << 'b'; 54 if (getKind().isWriteable()) 55 OS << 'w'; 56 else 57 OS << 'r'; 58 if (getCharacteristics() & COFF::IMAGE_SCN_MEM_DISCARDABLE) 59 OS << 'n'; 60 if (getCharacteristics() & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA) 61 OS << 'd'; 62 OS << '"'; 63 64 if (getCharacteristics() & COFF::IMAGE_SCN_LNK_COMDAT) { 65 OS << ","; 66 switch (Selection) { 67 case COFF::IMAGE_COMDAT_SELECT_NODUPLICATES: 68 OS << "one_only,"; 69 break; 70 case COFF::IMAGE_COMDAT_SELECT_ANY: 71 OS << "discard,"; 72 break; 73 case COFF::IMAGE_COMDAT_SELECT_SAME_SIZE: 74 OS << "same_size,"; 75 break; 76 case COFF::IMAGE_COMDAT_SELECT_EXACT_MATCH: 77 OS << "same_contents,"; 78 break; 79 case COFF::IMAGE_COMDAT_SELECT_ASSOCIATIVE: 80 OS << "associative,"; 81 break; 82 case COFF::IMAGE_COMDAT_SELECT_LARGEST: 83 OS << "largest,"; 84 break; 85 case COFF::IMAGE_COMDAT_SELECT_NEWEST: 86 OS << "newest,"; 87 break; 88 default: 89 assert (0 && "unsupported COFF selection type"); 90 break; 91 } 92 assert(COMDATSymbol); 93 OS << *COMDATSymbol; 94 } 95 OS << '\n'; 96} 97 98bool MCSectionCOFF::UseCodeAlign() const { 99 return getKind().isText(); 100} 101 102bool MCSectionCOFF::isVirtualSection() const { 103 return getCharacteristics() & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA; 104} 105