| //===- 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"; } |