llvm-project/lld/lib/Core/DefinedAtom.cpp

//===- DefinedAtom.cpp ------------------------------------------*- C++ -*-===//
//
//                             The LLVM Linker
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

#include "llvm/Support/ErrorHandling.h"
#include "lld/Core/DefinedAtom.h"
#include "lld/Core/File.h"

namespace lld {

DefinedAtom::ContentPermissions DefinedAtom::permissions() const {
  // By default base permissions on content type.
  return permissions(this->contentType());
}

// Utility function for deriving permissions from content type
DefinedAtom::ContentPermissions DefinedAtom::permissions(ContentType type) {
  switch (type) {
  case typeCode:
  case typeResolver:
  case typeBranchIsland:
  case typeBranchShim:
  case typeStub:
  case typeStubHelper:
  case typeMachHeader:
    return permR_X;

  case typeConstant:
  case typeCString:
  case typeUTF16String:
  case typeCFI:
  case typeLSDA:
  case typeLiteral4:
  case typeLiteral8:
  case typeLiteral16:
  case typeDTraceDOF:
  case typeCompactUnwindInfo:
  case typeProcessedUnwindInfo:
  case typeRONote:
  case typeNoAlloc:
    return permR__;

  case typeData:
  case typeDataFast:
  case typeZeroFill:
  case typeZeroFillFast:
  case typeObjC1Class:
  case typeLazyPointer:
  case typeLazyDylibPointer:
  case typeThunkTLV:
  case typeRWNote:
    return permRW_;

  case typeGOT:
  case typeConstData:
  case typeCFString:
  case typeInitializerPtr:
  case typeTerminatorPtr:
  case typeCStringPtr:
  case typeObjCClassPtr:
  case typeObjC2CategoryList:
  case typeInterposingTuples:
  case typeTLVInitialData:
  case typeTLVInitialZeroFill:
  case typeTLVInitializerPtr:
  case typeThreadData:
  case typeThreadZeroFill:
    return permRW_L;

  case typeGroupComdat:
  case typeGnuLinkOnce:
  case typeUnknown:
  case typeTempLTO:
    return permUnknown;
  }
  llvm_unreachable("unknown content type");
}

bool DefinedAtom::compareByPosition(const DefinedAtom *lhs,
                                    const DefinedAtom *rhs) {
  if (lhs == rhs)
    return false;
  const File *lhsFile = &lhs->file();
  const File *rhsFile = &rhs->file();
  if (lhsFile->ordinal() != rhsFile->ordinal())
    return lhsFile->ordinal() < rhsFile->ordinal();
  assert(lhs->ordinal() != rhs->ordinal());
  return lhs->ordinal() < rhs->ordinal();
}

} // namespace