1 //===-- X86WinCOFFObjectWriter.cpp - X86 Win COFF 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/X86FixupKinds.h"
11 #include "MCTargetDesc/X86MCTargetDesc.h"
12 #include "llvm/MC/MCExpr.h"
13 #include "llvm/MC/MCValue.h"
14 #include "llvm/MC/MCWinCOFFObjectWriter.h"
15 #include "llvm/Support/COFF.h"
16 #include "llvm/Support/ErrorHandling.h"
17 
18 using namespace llvm;
19 
20 namespace llvm {
21   class MCObjectWriter;
22 }
23 
24 namespace {
25   class X86WinCOFFObjectWriter : public MCWinCOFFObjectTargetWriter {
26   public:
27     X86WinCOFFObjectWriter(bool Is64Bit);
28     ~X86WinCOFFObjectWriter() override;
29 
30     unsigned getRelocType(const MCValue &Target, const MCFixup &Fixup,
31                           bool IsCrossSection,
32                           const MCAsmBackend &MAB) const override;
33   };
34 }
35 
36 X86WinCOFFObjectWriter::X86WinCOFFObjectWriter(bool Is64Bit)
37     : MCWinCOFFObjectTargetWriter(Is64Bit ? COFF::IMAGE_FILE_MACHINE_AMD64
38                                           : COFF::IMAGE_FILE_MACHINE_I386) {}
39 
40 X86WinCOFFObjectWriter::~X86WinCOFFObjectWriter() {}
41 
42 unsigned X86WinCOFFObjectWriter::getRelocType(const MCValue &Target,
43                                               const MCFixup &Fixup,
44                                               bool IsCrossSection,
45                                               const MCAsmBackend &MAB) const {
46   unsigned FixupKind = IsCrossSection ? FK_PCRel_4 : Fixup.getKind();
47 
48   MCSymbolRefExpr::VariantKind Modifier = Target.isAbsolute() ?
49     MCSymbolRefExpr::VK_None : Target.getSymA()->getKind();
50 
51   if (getMachine() == COFF::IMAGE_FILE_MACHINE_AMD64) {
52     switch (FixupKind) {
53     case FK_PCRel_4:
54     case X86::reloc_riprel_4byte:
55     case X86::reloc_riprel_4byte_movq_load:
56     case X86::reloc_riprel_4byte_relax:
57     case X86::reloc_riprel_4byte_relax_rex:
58       return COFF::IMAGE_REL_AMD64_REL32;
59     case FK_Data_4:
60     case X86::reloc_signed_4byte:
61       if (Modifier == MCSymbolRefExpr::VK_COFF_IMGREL32)
62         return COFF::IMAGE_REL_AMD64_ADDR32NB;
63       if (Modifier == MCSymbolRefExpr::VK_SECREL)
64         return COFF::IMAGE_REL_AMD64_SECREL;
65       return COFF::IMAGE_REL_AMD64_ADDR32;
66     case FK_Data_8:
67       return COFF::IMAGE_REL_AMD64_ADDR64;
68     case FK_SecRel_2:
69       return COFF::IMAGE_REL_AMD64_SECTION;
70     case FK_SecRel_4:
71       return COFF::IMAGE_REL_AMD64_SECREL;
72     default:
73       llvm_unreachable("unsupported relocation type");
74     }
75   } else if (getMachine() == COFF::IMAGE_FILE_MACHINE_I386) {
76     switch (FixupKind) {
77     case FK_PCRel_4:
78     case X86::reloc_riprel_4byte:
79     case X86::reloc_riprel_4byte_movq_load:
80       return COFF::IMAGE_REL_I386_REL32;
81     case FK_Data_4:
82     case X86::reloc_signed_4byte:
83       if (Modifier == MCSymbolRefExpr::VK_COFF_IMGREL32)
84         return COFF::IMAGE_REL_I386_DIR32NB;
85       if (Modifier == MCSymbolRefExpr::VK_SECREL)
86         return COFF::IMAGE_REL_AMD64_SECREL;
87       return COFF::IMAGE_REL_I386_DIR32;
88     case FK_SecRel_2:
89       return COFF::IMAGE_REL_I386_SECTION;
90     case FK_SecRel_4:
91       return COFF::IMAGE_REL_I386_SECREL;
92     default:
93       llvm_unreachable("unsupported relocation type");
94     }
95   } else
96     llvm_unreachable("Unsupported COFF machine type.");
97 }
98 
99 MCObjectWriter *llvm::createX86WinCOFFObjectWriter(raw_pwrite_stream &OS,
100                                                    bool Is64Bit) {
101   MCWinCOFFObjectTargetWriter *MOTW = new X86WinCOFFObjectWriter(Is64Bit);
102   return createWinCOFFObjectWriter(MOTW, OS);
103 }
104