1 //===-- SparcELFObjectWriter.cpp - Sparc ELF Writer -----------------------===//
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/SparcFixupKinds.h"
10 #include "MCTargetDesc/SparcMCExpr.h"
11 #include "MCTargetDesc/SparcMCTargetDesc.h"
12 #include "llvm/ADT/STLExtras.h"
13 #include "llvm/MC/MCELFObjectWriter.h"
14 #include "llvm/MC/MCExpr.h"
15 #include "llvm/MC/MCObjectWriter.h"
16 #include "llvm/MC/MCValue.h"
17 #include "llvm/Support/ErrorHandling.h"
18 
19 using namespace llvm;
20 
21 namespace {
22   class SparcELFObjectWriter : public MCELFObjectTargetWriter {
23   public:
24     SparcELFObjectWriter(bool Is64Bit, uint8_t OSABI)
25       : MCELFObjectTargetWriter(Is64Bit, OSABI,
26                                 Is64Bit ?  ELF::EM_SPARCV9 : ELF::EM_SPARC,
27                                 /*HasRelocationAddend*/ true) {}
28 
29     ~SparcELFObjectWriter() override = default;
30 
31   protected:
32     unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
33                           const MCFixup &Fixup, bool IsPCRel) const override;
34 
35     bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
36                                  unsigned Type) const override;
37   };
38 }
39 
40 unsigned SparcELFObjectWriter::getRelocType(MCContext &Ctx,
41                                             const MCValue &Target,
42                                             const MCFixup &Fixup,
43                                             bool IsPCRel) const {
44   MCFixupKind Kind = Fixup.getKind();
45   if (Kind >= FirstLiteralRelocationKind)
46     return Kind - FirstLiteralRelocationKind;
47 
48   if (const SparcMCExpr *SExpr = dyn_cast<SparcMCExpr>(Fixup.getValue())) {
49     if (SExpr->getKind() == SparcMCExpr::VK_Sparc_R_DISP32)
50       return ELF::R_SPARC_DISP32;
51   }
52 
53   if (IsPCRel) {
54     switch(Fixup.getTargetKind()) {
55     default:
56       llvm_unreachable("Unimplemented fixup -> relocation");
57     case FK_Data_1:                  return ELF::R_SPARC_DISP8;
58     case FK_Data_2:                  return ELF::R_SPARC_DISP16;
59     case FK_Data_4:                  return ELF::R_SPARC_DISP32;
60     case FK_Data_8:                  return ELF::R_SPARC_DISP64;
61     case Sparc::fixup_sparc_call30:  return ELF::R_SPARC_WDISP30;
62     case Sparc::fixup_sparc_br22:    return ELF::R_SPARC_WDISP22;
63     case Sparc::fixup_sparc_br19:    return ELF::R_SPARC_WDISP19;
64     case Sparc::fixup_sparc_br16:
65       return ELF::R_SPARC_WDISP16;
66     case Sparc::fixup_sparc_pc22:    return ELF::R_SPARC_PC22;
67     case Sparc::fixup_sparc_pc10:    return ELF::R_SPARC_PC10;
68     case Sparc::fixup_sparc_wplt30:  return ELF::R_SPARC_WPLT30;
69     }
70   }
71 
72   switch(Fixup.getTargetKind()) {
73   default:
74     llvm_unreachable("Unimplemented fixup -> relocation");
75   case FK_NONE:                  return ELF::R_SPARC_NONE;
76   case FK_Data_1:                return ELF::R_SPARC_8;
77   case FK_Data_2:                return ((Fixup.getOffset() % 2)
78                                          ? ELF::R_SPARC_UA16
79                                          : ELF::R_SPARC_16);
80   case FK_Data_4:                return ((Fixup.getOffset() % 4)
81                                          ? ELF::R_SPARC_UA32
82                                          : ELF::R_SPARC_32);
83   case FK_Data_8:                return ((Fixup.getOffset() % 8)
84                                          ? ELF::R_SPARC_UA64
85                                          : ELF::R_SPARC_64);
86   case Sparc::fixup_sparc_13:    return ELF::R_SPARC_13;
87   case Sparc::fixup_sparc_hi22:  return ELF::R_SPARC_HI22;
88   case Sparc::fixup_sparc_lo10:  return ELF::R_SPARC_LO10;
89   case Sparc::fixup_sparc_h44:   return ELF::R_SPARC_H44;
90   case Sparc::fixup_sparc_m44:   return ELF::R_SPARC_M44;
91   case Sparc::fixup_sparc_l44:   return ELF::R_SPARC_L44;
92   case Sparc::fixup_sparc_hh:    return ELF::R_SPARC_HH22;
93   case Sparc::fixup_sparc_hm:    return ELF::R_SPARC_HM10;
94   case Sparc::fixup_sparc_lm:    return ELF::R_SPARC_LM22;
95   case Sparc::fixup_sparc_got22: return ELF::R_SPARC_GOT22;
96   case Sparc::fixup_sparc_got10: return ELF::R_SPARC_GOT10;
97   case Sparc::fixup_sparc_got13: return ELF::R_SPARC_GOT13;
98   case Sparc::fixup_sparc_tls_gd_hi22:   return ELF::R_SPARC_TLS_GD_HI22;
99   case Sparc::fixup_sparc_tls_gd_lo10:   return ELF::R_SPARC_TLS_GD_LO10;
100   case Sparc::fixup_sparc_tls_gd_add:    return ELF::R_SPARC_TLS_GD_ADD;
101   case Sparc::fixup_sparc_tls_gd_call:   return ELF::R_SPARC_TLS_GD_CALL;
102   case Sparc::fixup_sparc_tls_ldm_hi22:  return ELF::R_SPARC_TLS_LDM_HI22;
103   case Sparc::fixup_sparc_tls_ldm_lo10:  return ELF::R_SPARC_TLS_LDM_LO10;
104   case Sparc::fixup_sparc_tls_ldm_add:   return ELF::R_SPARC_TLS_LDM_ADD;
105   case Sparc::fixup_sparc_tls_ldm_call:  return ELF::R_SPARC_TLS_LDM_CALL;
106   case Sparc::fixup_sparc_tls_ldo_hix22: return ELF::R_SPARC_TLS_LDO_HIX22;
107   case Sparc::fixup_sparc_tls_ldo_lox10: return ELF::R_SPARC_TLS_LDO_LOX10;
108   case Sparc::fixup_sparc_tls_ldo_add:   return ELF::R_SPARC_TLS_LDO_ADD;
109   case Sparc::fixup_sparc_tls_ie_hi22:   return ELF::R_SPARC_TLS_IE_HI22;
110   case Sparc::fixup_sparc_tls_ie_lo10:   return ELF::R_SPARC_TLS_IE_LO10;
111   case Sparc::fixup_sparc_tls_ie_ld:     return ELF::R_SPARC_TLS_IE_LD;
112   case Sparc::fixup_sparc_tls_ie_ldx:    return ELF::R_SPARC_TLS_IE_LDX;
113   case Sparc::fixup_sparc_tls_ie_add:    return ELF::R_SPARC_TLS_IE_ADD;
114   case Sparc::fixup_sparc_tls_le_hix22:  return ELF::R_SPARC_TLS_LE_HIX22;
115   case Sparc::fixup_sparc_tls_le_lox10:  return ELF::R_SPARC_TLS_LE_LOX10;
116   case Sparc::fixup_sparc_hix22:         return ELF::R_SPARC_HIX22;
117   case Sparc::fixup_sparc_lox10:         return ELF::R_SPARC_LOX10;
118   case Sparc::fixup_sparc_gotdata_hix22: return ELF::R_SPARC_GOTDATA_HIX22;
119   case Sparc::fixup_sparc_gotdata_lox10: return ELF::R_SPARC_GOTDATA_LOX10;
120   case Sparc::fixup_sparc_gotdata_op:    return ELF::R_SPARC_GOTDATA_OP;
121   }
122 
123   return ELF::R_SPARC_NONE;
124 }
125 
126 bool SparcELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
127                                                    const MCSymbol &,
128                                                    unsigned Type) const {
129   switch (Type) {
130     default:
131       return false;
132 
133     // All relocations that use a GOT need a symbol, not an offset, as
134     // the offset of the symbol within the section is irrelevant to
135     // where the GOT entry is. Don't need to list all the TLS entries,
136     // as they're all marked as requiring a symbol anyways.
137     case ELF::R_SPARC_GOT10:
138     case ELF::R_SPARC_GOT13:
139     case ELF::R_SPARC_GOT22:
140     case ELF::R_SPARC_GOTDATA_HIX22:
141     case ELF::R_SPARC_GOTDATA_LOX10:
142     case ELF::R_SPARC_GOTDATA_OP_HIX22:
143     case ELF::R_SPARC_GOTDATA_OP_LOX10:
144       return true;
145   }
146 }
147 
148 std::unique_ptr<MCObjectTargetWriter>
149 llvm::createSparcELFObjectWriter(bool Is64Bit, uint8_t OSABI) {
150   return std::make_unique<SparcELFObjectWriter>(Is64Bit, OSABI);
151 }
152