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
|
//===- MachOObjcopy.cpp -----------------------------------------*- 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
//
//===----------------------------------------------------------------------===//
#include "MachOObjcopy.h"
#include "../CopyConfig.h"
#include "MachOReader.h"
#include "MachOWriter.h"
#include "llvm/Support/Errc.h"
#include "llvm/Support/Error.h"
namespace llvm {
namespace objcopy {
namespace macho {
using namespace object;
using SectionPred = std::function<bool(const Section &Sec)>;
static void removeSections(const CopyConfig &Config, Object &Obj) {
SectionPred RemovePred = [](const Section &) { return false; };
if (Config.StripAll) {
// Remove all debug sections.
RemovePred = [RemovePred](const Section &Sec) {
if (Sec.Segname == "__DWARF")
return true;
return RemovePred(Sec);
};
}
if (!Config.OnlySection.empty()) {
RemovePred = [&Config, RemovePred](const Section &Sec) {
return !Config.OnlySection.matches(Sec.CanonicalName);
};
}
return Obj.removeSections(RemovePred);
}
static void markSymbols(const CopyConfig &Config, Object &Obj) {
// Symbols referenced from the indirect symbol table must not be removed.
for (IndirectSymbolEntry &ISE : Obj.IndirectSymTable.Symbols)
if (ISE.Symbol)
(*ISE.Symbol)->Referenced = true;
}
static void removeSymbols(const CopyConfig &Config, Object &Obj) {
auto RemovePred = [Config](const std::unique_ptr<SymbolEntry> &N) {
if (N->Referenced)
return false;
return Config.StripAll;
};
Obj.SymTable.removeSymbols(RemovePred);
}
static Error handleArgs(const CopyConfig &Config, Object &Obj) {
if (Config.AllowBrokenLinks || !Config.BuildIdLinkDir.empty() ||
Config.BuildIdLinkInput || Config.BuildIdLinkOutput ||
!Config.SplitDWO.empty() || !Config.SymbolsPrefix.empty() ||
!Config.AllocSectionsPrefix.empty() || !Config.AddSection.empty() ||
!Config.DumpSection.empty() || !Config.KeepSection.empty() ||
Config.NewSymbolVisibility || !Config.SymbolsToGlobalize.empty() ||
!Config.SymbolsToKeep.empty() || !Config.SymbolsToLocalize.empty() ||
!Config.SymbolsToWeaken.empty() || !Config.SymbolsToKeepGlobal.empty() ||
!Config.SectionsToRename.empty() || !Config.SymbolsToRename.empty() ||
!Config.UnneededSymbolsToRemove.empty() ||
!Config.SetSectionAlignment.empty() || !Config.SetSectionFlags.empty() ||
!Config.ToRemove.empty() || Config.ExtractDWO || Config.KeepFileSymbols ||
Config.LocalizeHidden || Config.PreserveDates || Config.StripAllGNU ||
Config.StripDWO || Config.StripNonAlloc || Config.StripSections ||
Config.Weaken || Config.DecompressDebugSections || Config.StripDebug ||
Config.StripNonAlloc || Config.StripSections || Config.StripUnneeded ||
Config.DiscardMode != DiscardType::None || !Config.SymbolsToAdd.empty() ||
Config.EntryExpr) {
return createStringError(llvm::errc::invalid_argument,
"option not supported by llvm-objcopy for MachO");
}
removeSections(Config, Obj);
// Mark symbols to determine which symbols are still needed.
if (Config.StripAll)
markSymbols(Config, Obj);
removeSymbols(Config, Obj);
if (Config.StripAll)
for (LoadCommand &LC : Obj.LoadCommands)
for (Section &Sec : LC.Sections)
Sec.Relocations.clear();
return Error::success();
}
Error executeObjcopyOnBinary(const CopyConfig &Config,
object::MachOObjectFile &In, Buffer &Out) {
MachOReader Reader(In);
std::unique_ptr<Object> O = Reader.create();
if (!O)
return createFileError(
Config.InputFilename,
createStringError(object_error::parse_failed,
"unable to deserialize MachO object"));
if (Error E = handleArgs(Config, *O))
return createFileError(Config.InputFilename, std::move(E));
// TODO: Support 16KB pages which are employed in iOS arm64 binaries:
// https://github.com/llvm/llvm-project/commit/1bebb2832ee312d3b0316dacff457a7a29435edb
const uint64_t PageSize = 4096;
MachOWriter Writer(*O, In.is64Bit(), In.isLittleEndian(), PageSize, Out);
if (auto E = Writer.finalize())
return E;
return Writer.write();
}
} // end namespace macho
} // end namespace objcopy
} // end namespace llvm
|
