LLVM 17.0.0git
COFFObject.cpp
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1//===- COFFObject.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 "COFFObject.h"
10#include "llvm/ADT/DenseSet.h"
11#include <algorithm>
12
13namespace llvm {
14namespace objcopy {
15namespace coff {
16
17using namespace object;
18
20 for (Symbol S : NewSymbols) {
21 S.UniqueId = NextSymbolUniqueId++;
22 Symbols.emplace_back(S);
23 }
24 updateSymbols();
25}
26
27void Object::updateSymbols() {
28 SymbolMap = DenseMap<size_t, Symbol *>(Symbols.size());
29 for (Symbol &Sym : Symbols)
30 SymbolMap[Sym.UniqueId] = &Sym;
31}
32
33const Symbol *Object::findSymbol(size_t UniqueId) const {
34 return SymbolMap.lookup(UniqueId);
35}
36
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
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
69 for (Section S : NewSections) {
70 S.UniqueId = NextSectionUniqueId++;
71 Sections.emplace_back(S);
72 }
73 updateSections();
74}
75
76void 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
85const Section *Object::findSection(ssize_t UniqueId) const {
86 return SectionMap.lookup(UniqueId);
87}
88
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();
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.contains(Sym.AssociativeComdatTargetSectionId))
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
120void 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
ReachingDefAnalysis InstSet & ToRemove
This file defines the DenseSet and SmallDenseSet classes.
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: ArrayRef.h:41
Implements a dense probed hash-table based set.
Definition: DenseSet.h:271
Lightweight error class with error context and mandatory checking.
Definition: Error.h:156
static ErrorSuccess success()
Create a success value.
Definition: Error.h:330
Tagged union holding either a T or a Error.
Definition: Error.h:470
Error takeError()
Take ownership of the stored error.
Definition: Error.h:597
std::pair< iterator, bool > insert(const ValueT &V)
Definition: DenseSet.h:206
bool contains(const_arg_type_t< ValueT > V) const
Check if the set contains the given element.
Definition: DenseSet.h:185
An efficient, type-erasing, non-owning reference to a callable.
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
Error createStringError(std::error_code EC, char const *Fmt, const Ts &... Vals)
Create formatted StringError object.
Definition: Error.h:1246
Error joinErrors(Error E1, Error E2)
Concatenate errors.
Definition: Error.h:427
void erase_if(Container &C, UnaryPredicate P)
Provide a container algorithm similar to C++ Library Fundamentals v2's erase_if which is equivalent t...
Definition: STLExtras.h:1998
void truncateSections(function_ref< bool(const Section &)> ToTruncate)
Definition: COFFObject.cpp:120
const Symbol * findSymbol(size_t UniqueId) const
Definition: COFFObject.cpp:33
const Section * findSection(ssize_t UniqueId) const
Definition: COFFObject.cpp:85
void addSections(ArrayRef< Section > NewSections)
Definition: COFFObject.cpp:68
void removeSections(function_ref< bool(const Section &)> ToRemove)
Definition: COFFObject.cpp:89
void addSymbols(ArrayRef< Symbol > NewSymbols)
Definition: COFFObject.cpp:19
Error removeSymbols(function_ref< Expected< bool >(const Symbol &)> ToRemove)
Definition: COFFObject.cpp:37
ssize_t AssociativeComdatTargetSectionId
Definition: COFFObject.h:88