1 //===- SPARCV9.cpp --------------------------------------------------------===//
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 "InputFiles.h"
10 #include "Symbols.h"
11 #include "SyntheticSections.h"
12 #include "Target.h"
13 #include "lld/Common/ErrorHandler.h"
14 #include "llvm/Support/Endian.h"
15 
16 using namespace llvm;
17 using namespace llvm::support::endian;
18 using namespace llvm::ELF;
19 
20 namespace lld {
21 namespace elf {
22 
23 namespace {
24 class SPARCV9 final : public TargetInfo {
25 public:
26   SPARCV9();
27   RelExpr getRelExpr(RelType type, const Symbol &s,
28                      const uint8_t *loc) const override;
29   void writePlt(uint8_t *buf, const Symbol &sym,
30                 uint64_t pltEntryAddr) const override;
31   void relocateOne(uint8_t *loc, RelType type, uint64_t val) const override;
32 };
33 } // namespace
34 
35 SPARCV9::SPARCV9() {
36   copyRel = R_SPARC_COPY;
37   gotRel = R_SPARC_GLOB_DAT;
38   noneRel = R_SPARC_NONE;
39   pltRel = R_SPARC_JMP_SLOT;
40   relativeRel = R_SPARC_RELATIVE;
41   symbolicRel = R_SPARC_64;
42   pltEntrySize = 32;
43   pltHeaderSize = 4 * pltEntrySize;
44 
45   defaultCommonPageSize = 8192;
46   defaultMaxPageSize = 0x100000;
47   defaultImageBase = 0x100000;
48 }
49 
50 RelExpr SPARCV9::getRelExpr(RelType type, const Symbol &s,
51                             const uint8_t *loc) const {
52   switch (type) {
53   case R_SPARC_32:
54   case R_SPARC_UA32:
55   case R_SPARC_64:
56   case R_SPARC_UA64:
57     return R_ABS;
58   case R_SPARC_PC10:
59   case R_SPARC_PC22:
60   case R_SPARC_DISP32:
61   case R_SPARC_WDISP30:
62     return R_PC;
63   case R_SPARC_GOT10:
64     return R_GOT_OFF;
65   case R_SPARC_GOT22:
66     return R_GOT_OFF;
67   case R_SPARC_WPLT30:
68     return R_PLT_PC;
69   case R_SPARC_NONE:
70     return R_NONE;
71   default:
72     error(getErrorLocation(loc) + "unknown relocation (" + Twine(type) +
73           ") against symbol " + toString(s));
74     return R_NONE;
75   }
76 }
77 
78 void SPARCV9::relocateOne(uint8_t *loc, RelType type, uint64_t val) const {
79   switch (type) {
80   case R_SPARC_32:
81   case R_SPARC_UA32:
82     // V-word32
83     checkUInt(loc, val, 32, type);
84     write32be(loc, val);
85     break;
86   case R_SPARC_DISP32:
87     // V-disp32
88     checkInt(loc, val, 32, type);
89     write32be(loc, val);
90     break;
91   case R_SPARC_WDISP30:
92   case R_SPARC_WPLT30:
93     // V-disp30
94     checkInt(loc, val, 32, type);
95     write32be(loc, (read32be(loc) & ~0x3fffffff) | ((val >> 2) & 0x3fffffff));
96     break;
97   case R_SPARC_22:
98     // V-imm22
99     checkUInt(loc, val, 22, type);
100     write32be(loc, (read32be(loc) & ~0x003fffff) | (val & 0x003fffff));
101     break;
102   case R_SPARC_GOT22:
103   case R_SPARC_PC22:
104     // T-imm22
105     write32be(loc, (read32be(loc) & ~0x003fffff) | ((val >> 10) & 0x003fffff));
106     break;
107   case R_SPARC_WDISP19:
108     // V-disp19
109     checkInt(loc, val, 21, type);
110     write32be(loc, (read32be(loc) & ~0x0007ffff) | ((val >> 2) & 0x0007ffff));
111     break;
112   case R_SPARC_GOT10:
113   case R_SPARC_PC10:
114     // T-simm10
115     write32be(loc, (read32be(loc) & ~0x000003ff) | (val & 0x000003ff));
116     break;
117   case R_SPARC_64:
118   case R_SPARC_UA64:
119     // V-xword64
120     write64be(loc, val);
121     break;
122   default:
123     llvm_unreachable("unknown relocation");
124   }
125 }
126 
127 void SPARCV9::writePlt(uint8_t *buf, const Symbol & /*sym*/,
128                        uint64_t pltEntryAddr) const {
129   const uint8_t pltData[] = {
130       0x03, 0x00, 0x00, 0x00, // sethi   (. - .PLT0), %g1
131       0x30, 0x68, 0x00, 0x00, // ba,a    %xcc, .PLT1
132       0x01, 0x00, 0x00, 0x00, // nop
133       0x01, 0x00, 0x00, 0x00, // nop
134       0x01, 0x00, 0x00, 0x00, // nop
135       0x01, 0x00, 0x00, 0x00, // nop
136       0x01, 0x00, 0x00, 0x00, // nop
137       0x01, 0x00, 0x00, 0x00  // nop
138   };
139   memcpy(buf, pltData, sizeof(pltData));
140 
141   uint64_t off = pltEntryAddr - in.plt->getVA();
142   relocateOne(buf, R_SPARC_22, off);
143   relocateOne(buf + 4, R_SPARC_WDISP19, -(off + 4 - pltEntrySize));
144 }
145 
146 TargetInfo *getSPARCV9TargetInfo() {
147   static SPARCV9 target;
148   return ⌖
149 }
150 
151 } // namespace elf
152 } // namespace lld
153