1 //===-- ARMWinCOFFObjectWriter.cpp - ARM Windows COFF Object 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/ARMFixupKinds.h"
10 #include "llvm/ADT/Twine.h"
11 #include "llvm/BinaryFormat/COFF.h"
12 #include "llvm/MC/MCAsmBackend.h"
13 #include "llvm/MC/MCExpr.h"
14 #include "llvm/MC/MCFixup.h"
15 #include "llvm/MC/MCFixupKindInfo.h"
16 #include "llvm/MC/MCObjectWriter.h"
17 #include "llvm/MC/MCValue.h"
18 #include "llvm/MC/MCWinCOFFObjectWriter.h"
19 #include "llvm/Support/ErrorHandling.h"
20 #include "llvm/Support/raw_ostream.h"
21 #include <cassert>
22
23 using namespace llvm;
24
25 namespace {
26
27 class ARMWinCOFFObjectWriter : public MCWinCOFFObjectTargetWriter {
28 public:
ARMWinCOFFObjectWriter(bool Is64Bit)29 ARMWinCOFFObjectWriter(bool Is64Bit)
30 : MCWinCOFFObjectTargetWriter(COFF::IMAGE_FILE_MACHINE_ARMNT) {
31 assert(!Is64Bit && "AArch64 support not yet implemented");
32 }
33
34 ~ARMWinCOFFObjectWriter() override = default;
35
36 unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
37 const MCFixup &Fixup, bool IsCrossSection,
38 const MCAsmBackend &MAB) const override;
39
40 bool recordRelocation(const MCFixup &) const override;
41 };
42
43 } // end anonymous namespace
44
getRelocType(MCContext & Ctx,const MCValue & Target,const MCFixup & Fixup,bool IsCrossSection,const MCAsmBackend & MAB) const45 unsigned ARMWinCOFFObjectWriter::getRelocType(MCContext &Ctx,
46 const MCValue &Target,
47 const MCFixup &Fixup,
48 bool IsCrossSection,
49 const MCAsmBackend &MAB) const {
50 assert(getMachine() == COFF::IMAGE_FILE_MACHINE_ARMNT &&
51 "AArch64 support not yet implemented");
52
53 MCSymbolRefExpr::VariantKind Modifier =
54 Target.isAbsolute() ? MCSymbolRefExpr::VK_None : Target.getSymA()->getKind();
55
56 switch (static_cast<unsigned>(Fixup.getKind())) {
57 default: {
58 const MCFixupKindInfo &Info = MAB.getFixupKindInfo(Fixup.getKind());
59 report_fatal_error(Twine("unsupported relocation type: ") + Info.Name);
60 }
61 case FK_Data_4:
62 switch (Modifier) {
63 case MCSymbolRefExpr::VK_COFF_IMGREL32:
64 return COFF::IMAGE_REL_ARM_ADDR32NB;
65 case MCSymbolRefExpr::VK_SECREL:
66 return COFF::IMAGE_REL_ARM_SECREL;
67 default:
68 return COFF::IMAGE_REL_ARM_ADDR32;
69 }
70 case FK_SecRel_2:
71 return COFF::IMAGE_REL_ARM_SECTION;
72 case FK_SecRel_4:
73 return COFF::IMAGE_REL_ARM_SECREL;
74 case ARM::fixup_t2_condbranch:
75 return COFF::IMAGE_REL_ARM_BRANCH20T;
76 case ARM::fixup_t2_uncondbranch:
77 case ARM::fixup_arm_thumb_bl:
78 return COFF::IMAGE_REL_ARM_BRANCH24T;
79 case ARM::fixup_arm_thumb_blx:
80 return COFF::IMAGE_REL_ARM_BLX23T;
81 case ARM::fixup_t2_movw_lo16:
82 case ARM::fixup_t2_movt_hi16:
83 return COFF::IMAGE_REL_ARM_MOV32T;
84 }
85 }
86
recordRelocation(const MCFixup & Fixup) const87 bool ARMWinCOFFObjectWriter::recordRelocation(const MCFixup &Fixup) const {
88 return static_cast<unsigned>(Fixup.getKind()) != ARM::fixup_t2_movt_hi16;
89 }
90
91 namespace llvm {
92
93 std::unique_ptr<MCObjectTargetWriter>
createARMWinCOFFObjectWriter(bool Is64Bit)94 createARMWinCOFFObjectWriter(bool Is64Bit) {
95 return std::make_unique<ARMWinCOFFObjectWriter>(Is64Bit);
96 }
97
98 } // end namespace llvm
99