1 //===- Object.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 "Object.h"
10 #include "llvm/ADT/DenseSet.h"
11 #include <algorithm>
12
13 namespace llvm {
14 namespace objcopy {
15 namespace coff {
16
17 using namespace object;
18
addSymbols(ArrayRef<Symbol> NewSymbols)19 void Object::addSymbols(ArrayRef<Symbol> NewSymbols) {
20 for (Symbol S : NewSymbols) {
21 S.UniqueId = NextSymbolUniqueId++;
22 Symbols.emplace_back(S);
23 }
24 updateSymbols();
25 }
26
updateSymbols()27 void Object::updateSymbols() {
28 SymbolMap = DenseMap<size_t, Symbol *>(Symbols.size());
29 for (Symbol &Sym : Symbols)
30 SymbolMap[Sym.UniqueId] = &Sym;
31 }
32
findSymbol(size_t UniqueId) const33 const Symbol *Object::findSymbol(size_t UniqueId) const {
34 return SymbolMap.lookup(UniqueId);
35 }
36
removeSymbols(function_ref<Expected<bool> (const Symbol &)> ToRemove)37 Error Object::removeSymbols(
38 function_ref<Expected<bool>(const Symbol &)> ToRemove) {
39 Error Errs = Error::success();
40 llvm::erase_if(Symbols, [ToRemove, &Errs](const Symbol &Sym) {
41 Expected<bool> ShouldRemove = ToRemove(Sym);
42 if (!ShouldRemove) {
43 Errs = joinErrors(std::move(Errs), ShouldRemove.takeError());
44 return false;
45 }
46 return *ShouldRemove;
47 });
48
49 updateSymbols();
50 return Errs;
51 }
52
markSymbols()53 Error Object::markSymbols() {
54 for (Symbol &Sym : Symbols)
55 Sym.Referenced = false;
56 for (const Section &Sec : Sections) {
57 for (const Relocation &R : Sec.Relocs) {
58 auto It = SymbolMap.find(R.Target);
59 if (It == SymbolMap.end())
60 return createStringError(object_error::invalid_symbol_index,
61 "relocation target %zu not found", R.Target);
62 It->second->Referenced = true;
63 }
64 }
65 return Error::success();
66 }
67
addSections(ArrayRef<Section> NewSections)68 void Object::addSections(ArrayRef<Section> NewSections) {
69 for (Section S : NewSections) {
70 S.UniqueId = NextSectionUniqueId++;
71 Sections.emplace_back(S);
72 }
73 updateSections();
74 }
75
updateSections()76 void Object::updateSections() {
77 SectionMap = DenseMap<ssize_t, Section *>(Sections.size());
78 size_t Index = 1;
79 for (Section &S : Sections) {
80 SectionMap[S.UniqueId] = &S;
81 S.Index = Index++;
82 }
83 }
84
findSection(ssize_t UniqueId) const85 const Section *Object::findSection(ssize_t UniqueId) const {
86 return SectionMap.lookup(UniqueId);
87 }
88
removeSections(function_ref<bool (const Section &)> ToRemove)89 void Object::removeSections(function_ref<bool(const Section &)> ToRemove) {
90 DenseSet<ssize_t> AssociatedSections;
91 auto RemoveAssociated = [&AssociatedSections](const Section &Sec) {
92 return AssociatedSections.contains(Sec.UniqueId);
93 };
94 do {
95 DenseSet<ssize_t> RemovedSections;
96 llvm::erase_if(Sections, [ToRemove, &RemovedSections](const Section &Sec) {
97 bool Remove = ToRemove(Sec);
98 if (Remove)
99 RemovedSections.insert(Sec.UniqueId);
100 return Remove;
101 });
102 // Remove all symbols referring to the removed sections.
103 AssociatedSections.clear();
104 llvm::erase_if(
105 Symbols, [&RemovedSections, &AssociatedSections](const Symbol &Sym) {
106 // If there are sections that are associative to a removed
107 // section,
108 // remove those as well as nothing will include them (and we can't
109 // leave them dangling).
110 if (RemovedSections.count(Sym.AssociativeComdatTargetSectionId) == 1)
111 AssociatedSections.insert(Sym.TargetSectionId);
112 return RemovedSections.contains(Sym.TargetSectionId);
113 });
114 ToRemove = RemoveAssociated;
115 } while (!AssociatedSections.empty());
116 updateSections();
117 updateSymbols();
118 }
119
truncateSections(function_ref<bool (const Section &)> ToTruncate)120 void Object::truncateSections(function_ref<bool(const Section &)> ToTruncate) {
121 for (Section &Sec : Sections) {
122 if (ToTruncate(Sec)) {
123 Sec.clearContents();
124 Sec.Relocs.clear();
125 Sec.Header.SizeOfRawData = 0;
126 }
127 }
128 }
129
130 } // end namespace coff
131 } // end namespace objcopy
132 } // end namespace llvm
133