1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207
|
//===- lib/MC/MCSectionELF.cpp - ELF Code Section Representation ----------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#include "llvm/MC/MCSectionELF.h"
#include "llvm/ADT/Triple.h"
#include "llvm/BinaryFormat/ELF.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include <cassert>
using namespace llvm;
// Decides whether a '.section' directive
// should be printed before the section name.
bool MCSectionELF::ShouldOmitSectionDirective(StringRef Name,
const MCAsmInfo &MAI) const {
if (isUnique())
return false;
return MAI.shouldOmitSectionDirective(Name);
}
static void printName(raw_ostream &OS, StringRef Name) {
if (Name.find_first_not_of("0123456789_."
"abcdefghijklmnopqrstuvwxyz"
"ABCDEFGHIJKLMNOPQRSTUVWXYZ") == Name.npos) {
OS << Name;
return;
}
OS << '"';
for (const char *B = Name.begin(), *E = Name.end(); B < E; ++B) {
if (*B == '"') // Unquoted "
OS << "\\\"";
else if (*B != '\\') // Neither " or backslash
OS << *B;
else if (B + 1 == E) // Trailing backslash
OS << "\\\\";
else {
OS << B[0] << B[1]; // Quoted character
++B;
}
}
OS << '"';
}
void MCSectionELF::PrintSwitchToSection(const MCAsmInfo &MAI, const Triple &T,
raw_ostream &OS,
const MCExpr *Subsection) const {
if (ShouldOmitSectionDirective(getName(), MAI)) {
OS << '\t' << getName();
if (Subsection) {
OS << '\t';
Subsection->print(OS, &MAI);
}
OS << '\n';
return;
}
OS << "\t.section\t";
printName(OS, getName());
// Handle the weird solaris syntax if desired.
if (MAI.usesSunStyleELFSectionSwitchSyntax() &&
!(Flags & ELF::SHF_MERGE)) {
if (Flags & ELF::SHF_ALLOC)
OS << ",#alloc";
if (Flags & ELF::SHF_EXECINSTR)
OS << ",#execinstr";
if (Flags & ELF::SHF_WRITE)
OS << ",#write";
if (Flags & ELF::SHF_EXCLUDE)
OS << ",#exclude";
if (Flags & ELF::SHF_TLS)
OS << ",#tls";
OS << '\n';
return;
}
OS << ",\"";
if (Flags & ELF::SHF_ALLOC)
OS << 'a';
if (Flags & ELF::SHF_EXCLUDE)
OS << 'e';
if (Flags & ELF::SHF_EXECINSTR)
OS << 'x';
if (Flags & ELF::SHF_GROUP)
OS << 'G';
if (Flags & ELF::SHF_WRITE)
OS << 'w';
if (Flags & ELF::SHF_MERGE)
OS << 'M';
if (Flags & ELF::SHF_STRINGS)
OS << 'S';
if (Flags & ELF::SHF_TLS)
OS << 'T';
if (Flags & ELF::SHF_LINK_ORDER)
OS << 'o';
if (Flags & ELF::SHF_GNU_RETAIN)
OS << 'R';
// If there are target-specific flags, print them.
Triple::ArchType Arch = T.getArch();
if (Arch == Triple::xcore) {
if (Flags & ELF::XCORE_SHF_CP_SECTION)
OS << 'c';
if (Flags & ELF::XCORE_SHF_DP_SECTION)
OS << 'd';
} else if (T.isARM() || T.isThumb()) {
if (Flags & ELF::SHF_ARM_PURECODE)
OS << 'y';
} else if (Arch == Triple::hexagon) {
if (Flags & ELF::SHF_HEX_GPREL)
OS << 's';
}
OS << '"';
OS << ',';
// If comment string is '@', e.g. as on ARM - use '%' instead
if (MAI.getCommentString()[0] == '@')
OS << '%';
else
OS << '@';
if (Type == ELF::SHT_INIT_ARRAY)
OS << "init_array";
else if (Type == ELF::SHT_FINI_ARRAY)
OS << "fini_array";
else if (Type == ELF::SHT_PREINIT_ARRAY)
OS << "preinit_array";
else if (Type == ELF::SHT_NOBITS)
OS << "nobits";
else if (Type == ELF::SHT_NOTE)
OS << "note";
else if (Type == ELF::SHT_PROGBITS)
OS << "progbits";
else if (Type == ELF::SHT_X86_64_UNWIND)
OS << "unwind";
else if (Type == ELF::SHT_MIPS_DWARF)
// Print hex value of the flag while we do not have
// any standard symbolic representation of the flag.
OS << "0x7000001e";
else if (Type == ELF::SHT_LLVM_ODRTAB)
OS << "llvm_odrtab";
else if (Type == ELF::SHT_LLVM_LINKER_OPTIONS)
OS << "llvm_linker_options";
else if (Type == ELF::SHT_LLVM_CALL_GRAPH_PROFILE)
OS << "llvm_call_graph_profile";
else if (Type == ELF::SHT_LLVM_DEPENDENT_LIBRARIES)
OS << "llvm_dependent_libraries";
else if (Type == ELF::SHT_LLVM_SYMPART)
OS << "llvm_sympart";
else if (Type == ELF::SHT_LLVM_BB_ADDR_MAP)
OS << "llvm_bb_addr_map";
else
report_fatal_error("unsupported type 0x" + Twine::utohexstr(Type) +
" for section " + getName());
if (EntrySize) {
assert(Flags & ELF::SHF_MERGE);
OS << "," << EntrySize;
}
if (Flags & ELF::SHF_GROUP) {
OS << ",";
printName(OS, Group.getPointer()->getName());
if (isComdat())
OS << ",comdat";
}
if (Flags & ELF::SHF_LINK_ORDER) {
OS << ",";
if (LinkedToSym)
printName(OS, LinkedToSym->getName());
else
OS << '0';
}
if (isUnique())
OS << ",unique," << UniqueID;
OS << '\n';
if (Subsection) {
OS << "\t.subsection\t";
Subsection->print(OS, &MAI);
OS << '\n';
}
}
bool MCSectionELF::UseCodeAlign() const {
return getFlags() & ELF::SHF_EXECINSTR;
}
bool MCSectionELF::isVirtualSection() const {
return getType() == ELF::SHT_NOBITS;
}
StringRef MCSectionELF::getVirtualSectionKind() const { return "SHT_NOBITS"; }
|