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 "MCTargetDesc/ARMMCAsmInfo.h"
11#include "llvm/ADT/Twine.h"
12#include "llvm/BinaryFormat/COFF.h"
13#include "llvm/MC/MCAsmBackend.h"
14#include "llvm/MC/MCContext.h"
15#include "llvm/MC/MCExpr.h"
16#include "llvm/MC/MCFixup.h"
17#include "llvm/MC/MCObjectWriter.h"
18#include "llvm/MC/MCValue.h"
19#include "llvm/MC/MCWinCOFFObjectWriter.h"
20#include "llvm/Support/ErrorHandling.h"
21
22using namespace llvm;
23
24namespace {
25
26class ARMWinCOFFObjectWriter : public MCWinCOFFObjectTargetWriter {
27public:
28 ARMWinCOFFObjectWriter()
29 : MCWinCOFFObjectTargetWriter(COFF::IMAGE_FILE_MACHINE_ARMNT) {
30 }
31
32 ~ARMWinCOFFObjectWriter() override = default;
33
34 unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
35 const MCFixup &Fixup, bool IsCrossSection,
36 const MCAsmBackend &MAB) const override;
37
38 bool recordRelocation(const MCFixup &) const override;
39};
40
41} // end anonymous namespace
42
43unsigned ARMWinCOFFObjectWriter::getRelocType(MCContext &Ctx,
44 const MCValue &Target,
45 const MCFixup &Fixup,
46 bool IsCrossSection,
47 const MCAsmBackend &MAB) const {
48 auto Spec = Target.getSpecifier();
49 unsigned FixupKind = Fixup.getKind();
50 if (IsCrossSection) {
51 if (FixupKind != FK_Data_4) {
52 Ctx.reportError(L: Fixup.getLoc(), Msg: "Cannot represent this expression");
53 return COFF::IMAGE_REL_ARM_ADDR32;
54 }
55 FixupKind = FK_PCRel_4;
56 }
57
58
59 switch (FixupKind) {
60 default: {
61 Ctx.reportError(L: Fixup.getLoc(), Msg: "unsupported relocation type");
62 return COFF::IMAGE_REL_ARM_ABSOLUTE;
63 }
64 case FK_Data_4:
65 switch (Spec) {
66 case MCSymbolRefExpr::VK_COFF_IMGREL32:
67 return COFF::IMAGE_REL_ARM_ADDR32NB;
68 case ARM::S_COFF_SECREL:
69 return COFF::IMAGE_REL_ARM_SECREL;
70 default:
71 return COFF::IMAGE_REL_ARM_ADDR32;
72 }
73 case FK_PCRel_4:
74 return COFF::IMAGE_REL_ARM_REL32;
75 case FK_SecRel_2:
76 return COFF::IMAGE_REL_ARM_SECTION;
77 case FK_SecRel_4:
78 return COFF::IMAGE_REL_ARM_SECREL;
79 case ARM::fixup_t2_condbranch:
80 return COFF::IMAGE_REL_ARM_BRANCH20T;
81 case ARM::fixup_t2_uncondbranch:
82 case ARM::fixup_arm_thumb_bl:
83 return COFF::IMAGE_REL_ARM_BRANCH24T;
84 case ARM::fixup_arm_thumb_blx:
85 return COFF::IMAGE_REL_ARM_BLX23T;
86 case ARM::fixup_t2_movw_lo16:
87 case ARM::fixup_t2_movt_hi16:
88 return COFF::IMAGE_REL_ARM_MOV32T;
89 }
90}
91
92bool ARMWinCOFFObjectWriter::recordRelocation(const MCFixup &Fixup) const {
93 return static_cast<unsigned>(Fixup.getKind()) != ARM::fixup_t2_movt_hi16;
94}
95
96namespace llvm {
97
98std::unique_ptr<MCObjectTargetWriter>
99createARMWinCOFFObjectWriter() {
100 return std::make_unique<ARMWinCOFFObjectWriter>();
101}
102
103} // end namespace llvm
104