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
|
//===- lib/ReaderWriter/MachO/ObjCPass.cpp -------------------------------===//
//
// The LLVM Linker
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
//===----------------------------------------------------------------------===//
#include "ArchHandler.h"
#include "File.h"
#include "MachONormalizedFileBinaryUtils.h"
#include "MachOPasses.h"
#include "lld/Core/DefinedAtom.h"
#include "lld/Core/File.h"
#include "lld/Core/LLVM.h"
#include "lld/Core/Reference.h"
#include "lld/Core/Simple.h"
#include "lld/ReaderWriter/MachOLinkingContext.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/STLExtras.h"
namespace lld {
namespace mach_o {
///
/// ObjC Image Info Atom created by the ObjC pass.
///
class ObjCImageInfoAtom : public SimpleDefinedAtom {
public:
ObjCImageInfoAtom(const File &file, bool isBig,
MachOLinkingContext::ObjCConstraint objCConstraint,
uint32_t swiftVersion)
: SimpleDefinedAtom(file) {
Data.info.version = 0;
switch (objCConstraint) {
case MachOLinkingContext::objc_unknown:
llvm_unreachable("Shouldn't run the objc pass without a constraint");
case MachOLinkingContext::objc_supports_gc:
case MachOLinkingContext::objc_gc_only:
llvm_unreachable("GC is not supported");
case MachOLinkingContext::objc_retainReleaseForSimulator:
// The retain/release for simulator flag is already the correct
// encoded value for the data so just set it here.
Data.info.flags = (uint32_t)objCConstraint;
break;
case MachOLinkingContext::objc_retainRelease:
// We don't need to encode this flag, so just leave the flags as 0.
Data.info.flags = 0;
break;
}
Data.info.flags |= (swiftVersion << 8);
normalized::write32(Data.bytes + 4, Data.info.flags, isBig);
}
~ObjCImageInfoAtom() override = default;
ContentType contentType() const override {
return DefinedAtom::typeObjCImageInfo;
}
Alignment alignment() const override {
return 4;
}
uint64_t size() const override {
return 8;
}
ContentPermissions permissions() const override {
return DefinedAtom::permR__;
}
ArrayRef<uint8_t> rawContent() const override {
return llvm::makeArrayRef(Data.bytes, size());
}
private:
struct objc_image_info {
uint32_t version;
uint32_t flags;
};
union {
objc_image_info info;
uint8_t bytes[8];
} Data;
};
class ObjCPass : public Pass {
public:
ObjCPass(const MachOLinkingContext &context)
: _ctx(context),
_file(*_ctx.make_file<MachOFile>("<mach-o objc pass>")) {
_file.setOrdinal(_ctx.getNextOrdinalAndIncrement());
}
llvm::Error perform(SimpleFile &mergedFile) override {
// Add the image info.
mergedFile.addAtom(*getImageInfo());
return llvm::Error::success();
}
private:
const DefinedAtom* getImageInfo() {
bool IsBig = MachOLinkingContext::isBigEndian(_ctx.arch());
return new (_file.allocator()) ObjCImageInfoAtom(_file, IsBig,
_ctx.objcConstraint(),
_ctx.swiftVersion());
}
const MachOLinkingContext &_ctx;
MachOFile &_file;
};
void addObjCPass(PassManager &pm, const MachOLinkingContext &ctx) {
pm.add(llvm::make_unique<ObjCPass>(ctx));
}
} // end namespace mach_o
} // end namespace lld
|
