1 //===-- llvm/Target/TargetELFWriterInfo.h - ELF Writer Info -----*- 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 // This file defines the TargetELFWriterInfo class. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #ifndef LLVM_TARGET_TARGETELFWRITERINFO_H 15 #define LLVM_TARGET_TARGETELFWRITERINFO_H 16 17 namespace llvm { 18 19 //===--------------------------------------------------------------------===// 20 // TargetELFWriterInfo 21 //===--------------------------------------------------------------------===// 22 23 class TargetELFWriterInfo { 24 protected: 25 // EMachine - This field is the target specific value to emit as the 26 // e_machine member of the ELF header. 27 unsigned short EMachine; 28 bool is64Bit, isLittleEndian; 29 public: 30 31 // Machine architectures 32 enum MachineType { 33 EM_NONE = 0, // No machine 34 EM_M32 = 1, // AT&T WE 32100 35 EM_SPARC = 2, // SPARC 36 EM_386 = 3, // Intel 386 37 EM_68K = 4, // Motorola 68000 38 EM_88K = 5, // Motorola 88000 39 EM_486 = 6, // Intel 486 (deprecated) 40 EM_860 = 7, // Intel 80860 41 EM_MIPS = 8, // MIPS R3000 42 EM_PPC = 20, // PowerPC 43 EM_ARM = 40, // ARM 44 EM_ALPHA = 41, // DEC Alpha 45 EM_SPARCV9 = 43, // SPARC V9 46 EM_X86_64 = 62 // AMD64 47 }; 48 49 // ELF File classes 50 enum { 51 ELFCLASS32 = 1, // 32-bit object file 52 ELFCLASS64 = 2 // 64-bit object file 53 }; 54 55 // ELF Endianess 56 enum { 57 ELFDATA2LSB = 1, // Little-endian object file 58 ELFDATA2MSB = 2 // Big-endian object file 59 }; 60 61 explicit TargetELFWriterInfo(bool is64Bit_, bool isLittleEndian_); 62 virtual ~TargetELFWriterInfo(); 63 getEMachine()64 unsigned short getEMachine() const { return EMachine; } getEFlags()65 unsigned getEFlags() const { return 0; } getEIClass()66 unsigned getEIClass() const { return is64Bit ? ELFCLASS64 : ELFCLASS32; } getEIData()67 unsigned getEIData() const { 68 return isLittleEndian ? ELFDATA2LSB : ELFDATA2MSB; 69 } 70 71 /// ELF Header and ELF Section Header Info getHdrSize()72 unsigned getHdrSize() const { return is64Bit ? 64 : 52; } getSHdrSize()73 unsigned getSHdrSize() const { return is64Bit ? 64 : 40; } 74 75 /// Symbol Table Info getSymTabEntrySize()76 unsigned getSymTabEntrySize() const { return is64Bit ? 24 : 16; } 77 78 /// getPrefELFAlignment - Returns the preferred alignment for ELF. This 79 /// is used to align some sections. getPrefELFAlignment()80 unsigned getPrefELFAlignment() const { return is64Bit ? 8 : 4; } 81 82 /// getRelocationEntrySize - Entry size used in the relocation section getRelocationEntrySize()83 unsigned getRelocationEntrySize() const { 84 return is64Bit ? (hasRelocationAddend() ? 24 : 16) 85 : (hasRelocationAddend() ? 12 : 8); 86 } 87 88 /// getRelocationType - Returns the target specific ELF Relocation type. 89 /// 'MachineRelTy' contains the object code independent relocation type 90 virtual unsigned getRelocationType(unsigned MachineRelTy) const = 0; 91 92 /// hasRelocationAddend - True if the target uses an addend in the 93 /// ELF relocation entry. 94 virtual bool hasRelocationAddend() const = 0; 95 96 /// getDefaultAddendForRelTy - Gets the default addend value for a 97 /// relocation entry based on the target ELF relocation type. 98 virtual long int getDefaultAddendForRelTy(unsigned RelTy, 99 long int Modifier = 0) const = 0; 100 101 /// getRelTySize - Returns the size of relocatable field in bits 102 virtual unsigned getRelocationTySize(unsigned RelTy) const = 0; 103 104 /// isPCRelativeRel - True if the relocation type is pc relative 105 virtual bool isPCRelativeRel(unsigned RelTy) const = 0; 106 107 /// getJumpTableRelocationTy - Returns the machine relocation type used 108 /// to reference a jumptable. 109 virtual unsigned getAbsoluteLabelMachineRelTy() const = 0; 110 111 /// computeRelocation - Some relocatable fields could be relocated 112 /// directly, avoiding the relocation symbol emission, compute the 113 /// final relocation value for this symbol. 114 virtual long int computeRelocation(unsigned SymOffset, unsigned RelOffset, 115 unsigned RelTy) const = 0; 116 }; 117 118 } // end llvm namespace 119 120 #endif // LLVM_TARGET_TARGETELFWRITERINFO_H 121