1 //===-- LoongArchELFObjectWriter.cpp - LoongArch ELF Writer ---*- C++ -*---===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "MCTargetDesc/LoongArchFixupKinds.h"
10 #include "MCTargetDesc/LoongArchMCTargetDesc.h"
11 #include "llvm/BinaryFormat/ELF.h"
12 #include "llvm/MC/MCContext.h"
13 #include "llvm/MC/MCELFObjectWriter.h"
14 #include "llvm/MC/MCFixup.h"
15 #include "llvm/MC/MCObjectWriter.h"
16 #include "llvm/Support/ErrorHandling.h"
17 
18 using namespace llvm;
19 
20 namespace {
21 class LoongArchELFObjectWriter : public MCELFObjectTargetWriter {
22 public:
23   LoongArchELFObjectWriter(uint8_t OSABI, bool Is64Bit, bool EnableRelax);
24 
25   ~LoongArchELFObjectWriter() override;
26 
27   bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
28                                unsigned Type) const override {
29     return EnableRelax;
30   }
31 
32 protected:
33   unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
34                         const MCFixup &Fixup, bool IsPCRel) const override;
35   bool EnableRelax;
36 };
37 } // end namespace
38 
39 LoongArchELFObjectWriter::LoongArchELFObjectWriter(uint8_t OSABI, bool Is64Bit,
40                                                    bool EnableRelax)
41     : MCELFObjectTargetWriter(Is64Bit, OSABI, ELF::EM_LOONGARCH,
42                               /*HasRelocationAddend=*/true),
43       EnableRelax(EnableRelax) {}
44 
45 LoongArchELFObjectWriter::~LoongArchELFObjectWriter() {}
46 
47 unsigned LoongArchELFObjectWriter::getRelocType(MCContext &Ctx,
48                                                 const MCValue &Target,
49                                                 const MCFixup &Fixup,
50                                                 bool IsPCRel) const {
51   // Determine the type of the relocation
52   unsigned Kind = Fixup.getTargetKind();
53 
54   if (Kind >= FirstLiteralRelocationKind)
55     return Kind - FirstLiteralRelocationKind;
56 
57   switch (Kind) {
58   default:
59     Ctx.reportError(Fixup.getLoc(), "Unsupported relocation type");
60     return ELF::R_LARCH_NONE;
61   case FK_Data_1:
62     Ctx.reportError(Fixup.getLoc(), "1-byte data relocations not supported");
63     return ELF::R_LARCH_NONE;
64   case FK_Data_2:
65     Ctx.reportError(Fixup.getLoc(), "2-byte data relocations not supported");
66     return ELF::R_LARCH_NONE;
67   case FK_Data_4:
68     return IsPCRel ? ELF::R_LARCH_32_PCREL : ELF::R_LARCH_32;
69   case FK_Data_8:
70     return IsPCRel ? ELF::R_LARCH_64_PCREL : ELF::R_LARCH_64;
71   case LoongArch::fixup_loongarch_b16:
72     return ELF::R_LARCH_B16;
73   case LoongArch::fixup_loongarch_b21:
74     return ELF::R_LARCH_B21;
75   case LoongArch::fixup_loongarch_b26:
76     return ELF::R_LARCH_B26;
77   case LoongArch::fixup_loongarch_abs_hi20:
78     return ELF::R_LARCH_ABS_HI20;
79   case LoongArch::fixup_loongarch_abs_lo12:
80     return ELF::R_LARCH_ABS_LO12;
81   case LoongArch::fixup_loongarch_abs64_lo20:
82     return ELF::R_LARCH_ABS64_LO20;
83   case LoongArch::fixup_loongarch_abs64_hi12:
84     return ELF::R_LARCH_ABS64_HI12;
85   case LoongArch::fixup_loongarch_tls_le_hi20:
86     return ELF::R_LARCH_TLS_LE_HI20;
87   case LoongArch::fixup_loongarch_tls_le_lo12:
88     return ELF::R_LARCH_TLS_LE_LO12;
89   case LoongArch::fixup_loongarch_tls_le64_lo20:
90     return ELF::R_LARCH_TLS_LE64_LO20;
91   case LoongArch::fixup_loongarch_tls_le64_hi12:
92     return ELF::R_LARCH_TLS_LE64_HI12;
93   case LoongArch::fixup_loongarch_call36:
94     return ELF::R_LARCH_CALL36;
95     // TODO: Handle more fixup-kinds.
96   }
97 }
98 
99 std::unique_ptr<MCObjectTargetWriter>
100 llvm::createLoongArchELFObjectWriter(uint8_t OSABI, bool Is64Bit, bool Relax) {
101   return std::make_unique<LoongArchELFObjectWriter>(OSABI, Is64Bit, Relax);
102 }
103