1243730Srwatson//===- lib/MC/MCSectionELF.cpp - ELF Code Section Representation ----------===// 2243730Srwatson// 3243730Srwatson// The LLVM Compiler Infrastructure 4243730Srwatson// 5243730Srwatson// This file is distributed under the University of Illinois Open Source 6243730Srwatson// License. See LICENSE.TXT for details. 7243730Srwatson// 8243730Srwatson//===----------------------------------------------------------------------===// 9243730Srwatson 10243730Srwatson#include "llvm/MC/MCSectionELF.h" 11243730Srwatson#include "llvm/MC/MCAsmInfo.h" 12243730Srwatson#include "llvm/MC/MCContext.h" 13243730Srwatson#include "llvm/MC/MCExpr.h" 14243730Srwatson#include "llvm/MC/MCSymbol.h" 15243730Srwatson#include "llvm/Support/ELF.h" 16243730Srwatson#include "llvm/Support/raw_ostream.h" 17243730Srwatson 18243730Srwatsonusing namespace llvm; 19243730Srwatson 20243730SrwatsonMCSectionELF::~MCSectionELF() {} // anchor. 21243730Srwatson 22243730Srwatson// ShouldOmitSectionDirective - Decides whether a '.section' directive 23243730Srwatson// should be printed before the section name 24243730Srwatsonbool MCSectionELF::ShouldOmitSectionDirective(StringRef Name, 25243730Srwatson const MCAsmInfo &MAI) const { 26243730Srwatson 27243730Srwatson // FIXME: Does .section .bss/.data/.text work everywhere?? 28243730Srwatson if (Name == ".text" || Name == ".data" || 29243734Srwatson (Name == ".bss" && !MAI.usesELFSectionDirectiveForBSS())) 30243730Srwatson return true; 31243730Srwatson 32243730Srwatson return false; 33243730Srwatson} 34243730Srwatson 35243730Srwatsonstatic void printName(raw_ostream &OS, StringRef Name) { 36243730Srwatson if (Name.find_first_not_of("0123456789_." 37243730Srwatson "abcdefghijklmnopqrstuvwxyz" 38243730Srwatson "ABCDEFGHIJKLMNOPQRSTUVWXYZ") == Name.npos) { 39243730Srwatson OS << Name; 40243730Srwatson return; 41243730Srwatson } 42243730Srwatson OS << '"'; 43243734Srwatson for (const char *B = Name.begin(), *E = Name.end(); B < E; ++B) { 44243730Srwatson if (*B == '"') // Unquoted " 45243730Srwatson OS << "\\\""; 46243730Srwatson else if (*B != '\\') // Neither " or backslash 47243730Srwatson OS << *B; 48243730Srwatson else if (B + 1 == E) // Trailing backslash 49243730Srwatson OS << "\\\\"; 50243730Srwatson else { 51243730Srwatson OS << B[0] << B[1]; // Quoted character 52243730Srwatson ++B; 53243730Srwatson } 54243730Srwatson } 55243730Srwatson OS << '"'; 56243730Srwatson} 57243730Srwatson 58243730Srwatsonvoid MCSectionELF::PrintSwitchToSection(const MCAsmInfo &MAI, 59243730Srwatson raw_ostream &OS, 60243730Srwatson const MCExpr *Subsection) const { 61243730Srwatson 62243730Srwatson if (ShouldOmitSectionDirective(SectionName, MAI)) { 63243730Srwatson OS << '\t' << getSectionName(); 64243730Srwatson if (Subsection) 65243730Srwatson OS << '\t' << *Subsection; 66243730Srwatson OS << '\n'; 67243730Srwatson return; 68243730Srwatson } 69243730Srwatson 70243730Srwatson OS << "\t.section\t"; 71243730Srwatson printName(OS, getSectionName()); 72243730Srwatson 73243730Srwatson // Handle the weird solaris syntax if desired. 74243730Srwatson if (MAI.usesSunStyleELFSectionSwitchSyntax() && 75243730Srwatson !(Flags & ELF::SHF_MERGE)) { 76243730Srwatson if (Flags & ELF::SHF_ALLOC) 77243730Srwatson OS << ",#alloc"; 78243730Srwatson if (Flags & ELF::SHF_EXECINSTR) 79243730Srwatson OS << ",#execinstr"; 80243730Srwatson if (Flags & ELF::SHF_WRITE) 81243730Srwatson OS << ",#write"; 82243730Srwatson if (Flags & ELF::SHF_EXCLUDE) 83243730Srwatson OS << ",#exclude"; 84243730Srwatson if (Flags & ELF::SHF_TLS) 85243730Srwatson OS << ",#tls"; 86243730Srwatson OS << '\n'; 87243730Srwatson return; 88243730Srwatson } 89243730Srwatson 90243730Srwatson OS << ",\""; 91243730Srwatson if (Flags & ELF::SHF_ALLOC) 92243730Srwatson OS << 'a'; 93243730Srwatson if (Flags & ELF::SHF_EXCLUDE) 94243730Srwatson OS << 'e'; 95243730Srwatson if (Flags & ELF::SHF_EXECINSTR) 96243730Srwatson OS << 'x'; 97243730Srwatson if (Flags & ELF::SHF_GROUP) 98243730Srwatson OS << 'G'; 99243730Srwatson if (Flags & ELF::SHF_WRITE) 100243730Srwatson OS << 'w'; 101243730Srwatson if (Flags & ELF::SHF_MERGE) 102243730Srwatson OS << 'M'; 103243730Srwatson if (Flags & ELF::SHF_STRINGS) 104243730Srwatson OS << 'S'; 105243730Srwatson if (Flags & ELF::SHF_TLS) 106243730Srwatson OS << 'T'; 107243730Srwatson 108243730Srwatson // If there are target-specific flags, print them. 109243730Srwatson if (Flags & ELF::XCORE_SHF_CP_SECTION) 110243730Srwatson OS << 'c'; 111243730Srwatson if (Flags & ELF::XCORE_SHF_DP_SECTION) 112243730Srwatson OS << 'd'; 113243730Srwatson 114243730Srwatson OS << '"'; 115243730Srwatson 116243730Srwatson OS << ','; 117243730Srwatson 118243730Srwatson // If comment string is '@', e.g. as on ARM - use '%' instead 119243730Srwatson if (MAI.getCommentString()[0] == '@') 120243730Srwatson OS << '%'; 121243730Srwatson else 122243730Srwatson OS << '@'; 123243730Srwatson 124243730Srwatson if (Type == ELF::SHT_INIT_ARRAY) 125243730Srwatson OS << "init_array"; 126243730Srwatson else if (Type == ELF::SHT_FINI_ARRAY) 127243730Srwatson OS << "fini_array"; 128243730Srwatson else if (Type == ELF::SHT_PREINIT_ARRAY) 129243730Srwatson OS << "preinit_array"; 130243730Srwatson else if (Type == ELF::SHT_NOBITS) 131243730Srwatson OS << "nobits"; 132243730Srwatson else if (Type == ELF::SHT_NOTE) 133243730Srwatson OS << "note"; 134243730Srwatson else if (Type == ELF::SHT_PROGBITS) 135243730Srwatson OS << "progbits"; 136243730Srwatson 137243730Srwatson if (EntrySize) { 138243730Srwatson assert(Flags & ELF::SHF_MERGE); 139243730Srwatson OS << "," << EntrySize; 140243730Srwatson } 141243730Srwatson 142243730Srwatson if (Flags & ELF::SHF_GROUP) { 143243730Srwatson OS << ","; 144243730Srwatson printName(OS, Group->getName()); 145243730Srwatson OS << ",comdat"; 146243730Srwatson } 147243730Srwatson OS << '\n'; 148243730Srwatson 149243730Srwatson if (Subsection) 150243730Srwatson OS << "\t.subsection\t" << *Subsection << '\n'; 151243730Srwatson} 152243730Srwatson 153243730Srwatsonbool MCSectionELF::UseCodeAlign() const { 154243730Srwatson return getFlags() & ELF::SHF_EXECINSTR; 155243730Srwatson} 156243730Srwatson 157243730Srwatsonbool MCSectionELF::isVirtualSection() const { 158243730Srwatson return getType() == ELF::SHT_NOBITS; 159243730Srwatson} 160243730Srwatson 161243730Srwatsonunsigned MCSectionELF::DetermineEntrySize(SectionKind Kind) { 162243730Srwatson if (Kind.isMergeable1ByteCString()) return 1; 163243730Srwatson if (Kind.isMergeable2ByteCString()) return 2; 164243730Srwatson if (Kind.isMergeable4ByteCString()) return 4; 165243730Srwatson if (Kind.isMergeableConst4()) return 4; 166243730Srwatson if (Kind.isMergeableConst8()) return 8; 167243730Srwatson if (Kind.isMergeableConst16()) return 16; 168243730Srwatson return 0; 169243730Srwatson} 170243730Srwatson