1 //===- ELFObjectFile.cpp - ELF object file implementation -------*- C++ -*-===// 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 // Part of the ELFObjectFile class implementation. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "llvm/Object/ELF.h" 15 #include "llvm/Support/MathExtras.h" 16 17 namespace llvm { 18 19 using namespace object; 20 21 // Creates an in-memory object-file by default: createELFObjectFile(Buffer) 22 ObjectFile *ObjectFile::createELFObjectFile(MemoryBuffer *Object) { 23 std::pair<unsigned char, unsigned char> Ident = getElfArchType(Object); 24 error_code ec; 25 26 std::size_t MaxAlignment = 27 1ULL << CountTrailingZeros_64(uintptr_t(Object->getBufferStart())); 28 29 if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2LSB) 30 if (MaxAlignment >= 4) 31 return new ELFObjectFile<ELFType<support::little, 4, false> >(Object, ec); 32 else if (MaxAlignment >= 2) 33 return new ELFObjectFile<ELFType<support::little, 2, false> >(Object, ec); 34 else 35 llvm_unreachable("Invalid alignment for ELF file!"); 36 else if (Ident.first == ELF::ELFCLASS32 && Ident.second == ELF::ELFDATA2MSB) 37 if (MaxAlignment >= 4) 38 return new ELFObjectFile<ELFType<support::big, 4, false> >(Object, ec); 39 else if (MaxAlignment >= 2) 40 return new ELFObjectFile<ELFType<support::big, 2, false> >(Object, ec); 41 else 42 llvm_unreachable("Invalid alignment for ELF file!"); 43 else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2MSB) 44 if (MaxAlignment >= 8) 45 return new ELFObjectFile<ELFType<support::big, 8, true> >(Object, ec); 46 else if (MaxAlignment >= 2) 47 return new ELFObjectFile<ELFType<support::big, 2, true> >(Object, ec); 48 else 49 llvm_unreachable("Invalid alignment for ELF file!"); 50 else if (Ident.first == ELF::ELFCLASS64 && Ident.second == ELF::ELFDATA2LSB) { 51 if (MaxAlignment >= 8) 52 return new ELFObjectFile<ELFType<support::little, 8, true> >(Object, ec); 53 else if (MaxAlignment >= 2) 54 return new ELFObjectFile<ELFType<support::little, 2, true> >(Object, ec); 55 else 56 llvm_unreachable("Invalid alignment for ELF file!"); 57 } 58 59 report_fatal_error("Buffer is not an ELF object file!"); 60 } 61 62 } // end namespace llvm 63