1 //===- MipsLA25Stub.cpp ---------------------------------------------------===//
2 //
3 // The MCLinker Project
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 #include "mcld/LD/ResolveInfo.h"
10 #include "MipsLA25Stub.h"
11 #include "MipsLDBackend.h"
12
13 namespace {
14
15 const uint32_t STUB[] = {
16 0x3c190000, // lui $25,%hi(func)
17 0x08000000, // j func
18 0x27390000, // add $25,$25,%lo(func)
19 0x00000000 // nop
20 };
21
22 enum {
23 // Fake relocations for patching LA25 stubs.
24 R_MIPS_LA25_LUI = 200,
25 R_MIPS_LA25_J = 201,
26 R_MIPS_LA25_ADD = 202
27 };
28
29 } // anonymous namespace
30
31 namespace mcld {
32
33 //===----------------------------------------------------------------------===//
34 // MipsLA25Stub
35 //===----------------------------------------------------------------------===//
36
MipsLA25Stub(const MipsGNULDBackend & pTarget)37 MipsLA25Stub::MipsLA25Stub(const MipsGNULDBackend& pTarget)
38 : m_Target(pTarget),
39 m_Name("MipsLA25_Prototype"),
40 m_pData(STUB),
41 m_Size(sizeof(STUB)) {
42 addFixup(0, 0x0, R_MIPS_LA25_LUI);
43 addFixup(4, 0x0, R_MIPS_LA25_J);
44 addFixup(8, 0x0, R_MIPS_LA25_ADD);
45 }
46
MipsLA25Stub(const MipsGNULDBackend & pTarget,const uint32_t * pData,size_t pSize,const_fixup_iterator pBegin,const_fixup_iterator pEnd)47 MipsLA25Stub::MipsLA25Stub(const MipsGNULDBackend& pTarget,
48 const uint32_t* pData,
49 size_t pSize,
50 const_fixup_iterator pBegin,
51 const_fixup_iterator pEnd)
52 : m_Target(pTarget), m_Name("pic"), m_pData(pData), m_Size(pSize) {
53 for (const_fixup_iterator it = pBegin, ie = pEnd; it != ie; ++it)
54 addFixup(**it);
55 }
56
isMyDuty(const Relocation & pReloc,uint64_t pSource,uint64_t pTargetSymValue) const57 bool MipsLA25Stub::isMyDuty(const Relocation& pReloc,
58 uint64_t pSource,
59 uint64_t pTargetSymValue) const {
60 if (llvm::ELF::R_MIPS_26 != pReloc.type())
61 return false;
62
63 const ResolveInfo* rsym = pReloc.symInfo();
64
65 if (!rsym->isDefine())
66 return false;
67
68 if (rsym->isDyn() || rsym->isUndef())
69 return false;
70
71 if (!m_Target.hasNonPICBranch(rsym))
72 return false;
73
74 return true;
75 }
76
name() const77 const std::string& MipsLA25Stub::name() const {
78 return m_Name;
79 }
80
getContent() const81 const uint8_t* MipsLA25Stub::getContent() const {
82 return reinterpret_cast<const uint8_t*>(m_pData);
83 }
84
size() const85 size_t MipsLA25Stub::size() const {
86 return m_Size;
87 }
88
alignment() const89 size_t MipsLA25Stub::alignment() const {
90 return 4;
91 }
92
doClone()93 Stub* MipsLA25Stub::doClone() {
94 return new MipsLA25Stub(
95 m_Target, m_pData, m_Size, fixup_begin(), fixup_end());
96 }
97
98 } // namespace mcld
99