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.
needsRelocateWithSymbol(const MCSymbol & Sym,unsigned Type) const28 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
RISCVELFObjectWriter(uint8_t OSABI,bool Is64Bit)41 RISCVELFObjectWriter::RISCVELFObjectWriter(uint8_t OSABI, bool Is64Bit)
42 : MCELFObjectTargetWriter(Is64Bit, OSABI, ELF::EM_RISCV,
43 /*HasRelocationAddend*/ true) {}
44
~RISCVELFObjectWriter()45 RISCVELFObjectWriter::~RISCVELFObjectWriter() {}
46
getRelocType(MCContext & Ctx,const MCValue & Target,const MCFixup & Fixup,bool IsPCRel) const47 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 case RISCV::fixup_riscv_relax:
98 return ELF::R_RISCV_RELAX;
99 }
100 }
101
102 std::unique_ptr<MCObjectTargetWriter>
createRISCVELFObjectWriter(uint8_t OSABI,bool Is64Bit)103 llvm::createRISCVELFObjectWriter(uint8_t OSABI, bool Is64Bit) {
104 return llvm::make_unique<RISCVELFObjectWriter>(OSABI, Is64Bit);
105 }
106