1 //===-- RISCVELFObjectWriter.cpp - RISCV ELF Writer -----------------------===// 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 #include "MCTargetDesc/RISCVFixupKinds.h" 11 #include "MCTargetDesc/RISCVMCTargetDesc.h" 12 #include "llvm/MC/MCELFObjectWriter.h" 13 #include "llvm/MC/MCFixup.h" 14 #include "llvm/MC/MCObjectWriter.h" 15 #include "llvm/Support/ErrorHandling.h" 16 17 using namespace llvm; 18 19 namespace { 20 class RISCVELFObjectWriter : public MCELFObjectTargetWriter { 21 public: 22 RISCVELFObjectWriter(uint8_t OSABI, bool Is64Bit); 23 24 ~RISCVELFObjectWriter() override; 25 26 // Return true if the given relocation must be with a symbol rather than 27 // section plus offset. 28 bool needsRelocateWithSymbol(const MCSymbol &Sym, 29 unsigned Type) const override { 30 // TODO: this is very conservative, update once RISC-V psABI requirements 31 // are clarified. 32 return true; 33 } 34 35 protected: 36 unsigned getRelocType(MCContext &Ctx, const MCValue &Target, 37 const MCFixup &Fixup, bool IsPCRel) const override; 38 }; 39 } 40 41 RISCVELFObjectWriter::RISCVELFObjectWriter(uint8_t OSABI, bool Is64Bit) 42 : MCELFObjectTargetWriter(Is64Bit, OSABI, ELF::EM_RISCV, 43 /*HasRelocationAddend*/ true) {} 44 45 RISCVELFObjectWriter::~RISCVELFObjectWriter() {} 46 47 unsigned RISCVELFObjectWriter::getRelocType(MCContext &Ctx, 48 const MCValue &Target, 49 const MCFixup &Fixup, 50 bool IsPCRel) const { 51 // Determine the type of the relocation 52 switch ((unsigned)Fixup.getKind()) { 53 default: 54 llvm_unreachable("invalid fixup kind!"); 55 case FK_Data_4: 56 return ELF::R_RISCV_32; 57 case FK_Data_8: 58 return ELF::R_RISCV_64; 59 case FK_Data_Add_1: 60 return ELF::R_RISCV_ADD8; 61 case FK_Data_Add_2: 62 return ELF::R_RISCV_ADD16; 63 case FK_Data_Add_4: 64 return ELF::R_RISCV_ADD32; 65 case FK_Data_Add_8: 66 return ELF::R_RISCV_ADD64; 67 case FK_Data_Sub_1: 68 return ELF::R_RISCV_SUB8; 69 case FK_Data_Sub_2: 70 return ELF::R_RISCV_SUB16; 71 case FK_Data_Sub_4: 72 return ELF::R_RISCV_SUB32; 73 case FK_Data_Sub_8: 74 return ELF::R_RISCV_SUB64; 75 case RISCV::fixup_riscv_hi20: 76 return ELF::R_RISCV_HI20; 77 case RISCV::fixup_riscv_lo12_i: 78 return ELF::R_RISCV_LO12_I; 79 case RISCV::fixup_riscv_lo12_s: 80 return ELF::R_RISCV_LO12_S; 81 case RISCV::fixup_riscv_pcrel_hi20: 82 return ELF::R_RISCV_PCREL_HI20; 83 case RISCV::fixup_riscv_pcrel_lo12_i: 84 return ELF::R_RISCV_PCREL_LO12_I; 85 case RISCV::fixup_riscv_pcrel_lo12_s: 86 return ELF::R_RISCV_PCREL_LO12_S; 87 case RISCV::fixup_riscv_jal: 88 return ELF::R_RISCV_JAL; 89 case RISCV::fixup_riscv_branch: 90 return ELF::R_RISCV_BRANCH; 91 case RISCV::fixup_riscv_rvc_jump: 92 return ELF::R_RISCV_RVC_JUMP; 93 case RISCV::fixup_riscv_rvc_branch: 94 return ELF::R_RISCV_RVC_BRANCH; 95 case RISCV::fixup_riscv_call: 96 return ELF::R_RISCV_CALL; 97 } 98 } 99 100 std::unique_ptr<MCObjectTargetWriter> 101 llvm::createRISCVELFObjectWriter(uint8_t OSABI, bool Is64Bit) { 102 return llvm::make_unique<RISCVELFObjectWriter>(OSABI, Is64Bit); 103 } 104