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);
24 
25   ~LoongArchELFObjectWriter() override;
26 
27 protected:
28   unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
29                         const MCFixup &Fixup, bool IsPCRel) const override;
30 };
31 } // end namespace
32 
33 LoongArchELFObjectWriter::LoongArchELFObjectWriter(uint8_t OSABI, bool Is64Bit)
34     : MCELFObjectTargetWriter(Is64Bit, OSABI, ELF::EM_LOONGARCH,
35                               /*HasRelocationAddend*/ true) {}
36 
37 LoongArchELFObjectWriter::~LoongArchELFObjectWriter() {}
38 
39 unsigned LoongArchELFObjectWriter::getRelocType(MCContext &Ctx,
40                                                 const MCValue &Target,
41                                                 const MCFixup &Fixup,
42                                                 bool IsPCRel) const {
43   // Determine the type of the relocation
44   unsigned Kind = Fixup.getTargetKind();
45 
46   if (Kind >= FirstLiteralRelocationKind)
47     return Kind - FirstLiteralRelocationKind;
48 
49   switch (Kind) {
50   default:
51     Ctx.reportError(Fixup.getLoc(), "Unsupported relocation type");
52     return ELF::R_LARCH_NONE;
53   case FK_Data_1:
54     Ctx.reportError(Fixup.getLoc(), "1-byte data relocations not supported");
55     return ELF::R_LARCH_NONE;
56   case FK_Data_2:
57     Ctx.reportError(Fixup.getLoc(), "2-byte data relocations not supported");
58     return ELF::R_LARCH_NONE;
59   case FK_Data_4:
60     return IsPCRel ? ELF::R_LARCH_32_PCREL : ELF::R_LARCH_32;
61   case FK_Data_8:
62     return IsPCRel ? ELF::R_LARCH_64_PCREL : ELF::R_LARCH_64;
63   case LoongArch::fixup_loongarch_b16:
64     return ELF::R_LARCH_B16;
65   case LoongArch::fixup_loongarch_b21:
66     return ELF::R_LARCH_B21;
67   case LoongArch::fixup_loongarch_b26:
68     return ELF::R_LARCH_B26;
69   case LoongArch::fixup_loongarch_abs_hi20:
70     return ELF::R_LARCH_ABS_HI20;
71   case LoongArch::fixup_loongarch_abs_lo12:
72     return ELF::R_LARCH_ABS_LO12;
73   case LoongArch::fixup_loongarch_abs64_lo20:
74     return ELF::R_LARCH_ABS64_LO20;
75   case LoongArch::fixup_loongarch_abs64_hi12:
76     return ELF::R_LARCH_ABS64_HI12;
77   case LoongArch::fixup_loongarch_tls_le_hi20:
78     return ELF::R_LARCH_TLS_LE_HI20;
79   case LoongArch::fixup_loongarch_tls_le_lo12:
80     return ELF::R_LARCH_TLS_LE_LO12;
81   case LoongArch::fixup_loongarch_tls_le64_lo20:
82     return ELF::R_LARCH_TLS_LE64_LO20;
83   case LoongArch::fixup_loongarch_tls_le64_hi12:
84     return ELF::R_LARCH_TLS_LE64_HI12;
85     // TODO: Handle more fixup-kinds.
86   }
87 }
88 
89 std::unique_ptr<MCObjectTargetWriter>
90 llvm::createLoongArchELFObjectWriter(uint8_t OSABI, bool Is64Bit) {
91   return std::make_unique<LoongArchELFObjectWriter>(OSABI, Is64Bit);
92 }
93