1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
| //===-- RuntimeDyldELF.h - Run-time dynamic linker for MC-JIT ---*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// ELF support for MC-JIT runtime dynamic linker.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_EXECUTIONENGINE_RUNTIMEDYLD_RUNTIMEDYLDELF_H
#define LLVM_LIB_EXECUTIONENGINE_RUNTIMEDYLD_RUNTIMEDYLDELF_H
#include "RuntimeDyldImpl.h"
#include "llvm/ADT/DenseMap.h"
using namespace llvm;
namespace llvm {
namespace object {
class ELFObjectFileBase;
}
class RuntimeDyldELF : public RuntimeDyldImpl {
void resolveRelocation(const SectionEntry &Section, uint64_t Offset,
uint64_t Value, uint32_t Type, int64_t Addend,
uint64_t SymOffset = 0, SID SectionID = 0);
void resolveX86_64Relocation(const SectionEntry &Section, uint64_t Offset,
uint64_t Value, uint32_t Type, int64_t Addend,
uint64_t SymOffset);
void resolveX86Relocation(const SectionEntry &Section, uint64_t Offset,
uint32_t Value, uint32_t Type, int32_t Addend);
void resolveAArch64Relocation(const SectionEntry &Section, uint64_t Offset,
uint64_t Value, uint32_t Type, int64_t Addend);
bool resolveAArch64ShortBranch(unsigned SectionID, relocation_iterator RelI,
const RelocationValueRef &Value);
void resolveAArch64Branch(unsigned SectionID, const RelocationValueRef &Value,
relocation_iterator RelI, StubMap &Stubs);
void resolveARMRelocation(const SectionEntry &Section, uint64_t Offset,
uint32_t Value, uint32_t Type, int32_t Addend);
void resolvePPC32Relocation(const SectionEntry &Section, uint64_t Offset,
uint64_t Value, uint32_t Type, int64_t Addend);
void resolvePPC64Relocation(const SectionEntry &Section, uint64_t Offset,
uint64_t Value, uint32_t Type, int64_t Addend);
void resolveSystemZRelocation(const SectionEntry &Section, uint64_t Offset,
uint64_t Value, uint32_t Type, int64_t Addend);
void resolveBPFRelocation(const SectionEntry &Section, uint64_t Offset,
uint64_t Value, uint32_t Type, int64_t Addend);
unsigned getMaxStubSize() const override {
if (Arch == Triple::aarch64 || Arch == Triple::aarch64_be)
return 20; // movz; movk; movk; movk; br
if (Arch == Triple::arm || Arch == Triple::thumb)
return 8; // 32-bit instruction and 32-bit address
else if (IsMipsO32ABI || IsMipsN32ABI)
return 16;
else if (IsMipsN64ABI)
return 32;
else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le)
return 44;
else if (Arch == Triple::x86_64)
return 6; // 2-byte jmp instruction + 32-bit relative address
else if (Arch == Triple::systemz)
return 16;
else
return 0;
}
unsigned getStubAlignment() override {
if (Arch == Triple::systemz)
return 8;
else
return 1;
}
void setMipsABI(const ObjectFile &Obj) override;
Error findPPC64TOCSection(const ELFObjectFileBase &Obj,
ObjSectionToIDMap &LocalSections,
RelocationValueRef &Rel);
Error findOPDEntrySection(const ELFObjectFileBase &Obj,
ObjSectionToIDMap &LocalSections,
RelocationValueRef &Rel);
protected:
size_t getGOTEntrySize() override;
private:
SectionEntry &getSection(unsigned SectionID) { return Sections[SectionID]; }
// Allocate no GOT entries for use in the given section.
uint64_t allocateGOTEntries(unsigned no);
// Find GOT entry corresponding to relocation or create new one.
uint64_t findOrAllocGOTEntry(const RelocationValueRef &Value,
unsigned GOTRelType);
// Resolve the relvative address of GOTOffset in Section ID and place
// it at the given Offset
void resolveGOTOffsetRelocation(unsigned SectionID, uint64_t Offset,
uint64_t GOTOffset, uint32_t Type);
// For a GOT entry referenced from SectionID, compute a relocation entry
// that will place the final resolved value in the GOT slot
RelocationEntry computeGOTOffsetRE(uint64_t GOTOffset, uint64_t SymbolOffset,
unsigned Type);
// Compute the address in memory where we can find the placeholder
void *computePlaceholderAddress(unsigned SectionID, uint64_t Offset) const;
// Split out common case for createing the RelocationEntry for when the relocation requires
// no particular advanced processing.
void processSimpleRelocation(unsigned SectionID, uint64_t Offset, unsigned RelType, RelocationValueRef Value);
// Return matching *LO16 relocation (Mips specific)
uint32_t getMatchingLoRelocation(uint32_t RelType,
bool IsLocal = false) const;
// The tentative ID for the GOT section
unsigned GOTSectionID;
// Records the current number of allocated slots in the GOT
// (This would be equivalent to GOTEntries.size() were it not for relocations
// that consume more than one slot)
unsigned CurrentGOTIndex;
protected:
// A map from section to a GOT section that has entries for section's GOT
// relocations. (Mips64 specific)
DenseMap<SID, SID> SectionToGOTMap;
private:
// A map to avoid duplicate got entries (Mips64 specific)
StringMap<uint64_t> GOTSymbolOffsets;
// *HI16 relocations will be added for resolving when we find matching
// *LO16 part. (Mips specific)
SmallVector<std::pair<RelocationValueRef, RelocationEntry>, 8> PendingRelocs;
// When a module is loaded we save the SectionID of the EH frame section
// in a table until we receive a request to register all unregistered
// EH frame sections with the memory manager.
SmallVector<SID, 2> UnregisteredEHFrameSections;
// Map between GOT relocation value and corresponding GOT offset
std::map<RelocationValueRef, uint64_t> GOTOffsetMap;
bool relocationNeedsGot(const RelocationRef &R) const override;
bool relocationNeedsStub(const RelocationRef &R) const override;
public:
RuntimeDyldELF(RuntimeDyld::MemoryManager &MemMgr,
JITSymbolResolver &Resolver);
~RuntimeDyldELF() override;
static std::unique_ptr<RuntimeDyldELF>
create(Triple::ArchType Arch, RuntimeDyld::MemoryManager &MemMgr,
JITSymbolResolver &Resolver);
std::unique_ptr<RuntimeDyld::LoadedObjectInfo>
loadObject(const object::ObjectFile &O) override;
void resolveRelocation(const RelocationEntry &RE, uint64_t Value) override;
Expected<relocation_iterator>
processRelocationRef(unsigned SectionID, relocation_iterator RelI,
const ObjectFile &Obj,
ObjSectionToIDMap &ObjSectionToID,
StubMap &Stubs) override;
bool isCompatibleFile(const object::ObjectFile &Obj) const override;
void registerEHFrames() override;
Error finalizeLoad(const ObjectFile &Obj,
ObjSectionToIDMap &SectionMap) override;
};
} // end namespace llvm
#endif
|