Bug Summary

File:src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/ExecutionEngine/Orc/ExecutionUtils.cpp
Warning:line 118, column 7
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple amd64-unknown-openbsd7.0 -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name ExecutionUtils.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 1 -fhalf-no-semantic-interposition -mframe-pointer=all -relaxed-aliasing -fno-rounding-math -mconstructor-aliases -munwind-tables -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -fcoverage-compilation-dir=/usr/src/gnu/usr.bin/clang/libLLVM/obj -resource-dir /usr/local/lib/clang/13.0.0 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/AMDGPU -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Analysis -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ASMParser -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/BinaryFormat -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Bitcode -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Bitcode -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Bitstream -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /include/llvm/CodeGen -I /include/llvm/CodeGen/PBQP -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/IR -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/IR -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Coroutines -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ProfileData/Coverage -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/CodeView -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/DWARF -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/MSF -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/PDB -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Demangle -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ExecutionEngine -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ExecutionEngine/JITLink -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ExecutionEngine/Orc -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend/OpenACC -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Frontend/OpenMP -I /include/llvm/CodeGen/GlobalISel -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/IRReader -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/InstCombine -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/Transforms/InstCombine -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/LTO -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Linker -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/MC -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/MC/MCParser -I /include/llvm/CodeGen/MIRParser -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Object -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Option -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Passes -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ProfileData -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Scalar -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ADT -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Support -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/DebugInfo/Symbolize -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Target -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Utils -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/Vectorize -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include/llvm/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/Target/X86 -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/Transforms/IPO -I /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include -I /usr/src/gnu/usr.bin/clang/libLLVM/../include -I /usr/src/gnu/usr.bin/clang/libLLVM/obj -I /usr/src/gnu/usr.bin/clang/libLLVM/obj/../include -D NDEBUG -D __STDC_LIMIT_MACROS -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D LLVM_PREFIX="/usr" -D PIC -internal-isystem /usr/include/c++/v1 -internal-isystem /usr/local/lib/clang/13.0.0/include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/usr/src/gnu/usr.bin/clang/libLLVM/obj -ferror-limit 19 -fvisibility-inlines-hidden -fwrapv -D_RET_PROTECTOR -ret-protector -fno-rtti -fgnuc-version=4.2.1 -vectorize-loops -vectorize-slp -fno-builtin-malloc -fno-builtin-calloc -fno-builtin-realloc -fno-builtin-valloc -fno-builtin-free -fno-builtin-strdup -fno-builtin-strndup -analyzer-output=html -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /home/ben/Projects/vmm/scan-build/2022-01-12-194120-40624-1 -x c++ /usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/ExecutionEngine/Orc/ExecutionUtils.cpp

/usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/lib/ExecutionEngine/Orc/ExecutionUtils.cpp

→
1//===---- ExecutionUtils.cpp - Utilities for executing functions in Orc ---===//
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 "llvm/ExecutionEngine/Orc/ExecutionUtils.h"
10#include "llvm/ExecutionEngine/Orc/Layer.h"
11#include "llvm/IR/Constants.h"
12#include "llvm/IR/Function.h"
13#include "llvm/IR/GlobalVariable.h"
14#include "llvm/IR/Module.h"
15#include "llvm/Object/MachOUniversal.h"
16#include "llvm/Support/FormatVariadic.h"
17#include "llvm/Support/TargetRegistry.h"
18#include "llvm/Target/TargetMachine.h"
19#include <string>
20
21namespace llvm {
22namespace orc {
23
24CtorDtorIterator::CtorDtorIterator(const GlobalVariable *GV, bool End)
25 : InitList(
26 GV ? dyn_cast_or_null<ConstantArray>(GV->getInitializer()) : nullptr),
27 I((InitList && End) ? InitList->getNumOperands() : 0) {
28}
29
30bool CtorDtorIterator::operator==(const CtorDtorIterator &Other) const {
31 assert(InitList == Other.InitList && "Incomparable iterators.")((void)0);
32 return I == Other.I;
33}
34
35bool CtorDtorIterator::operator!=(const CtorDtorIterator &Other) const {
36 return !(*this == Other);
37}
38
39CtorDtorIterator& CtorDtorIterator::operator++() {
40 ++I;
41 return *this;
42}
43
44CtorDtorIterator CtorDtorIterator::operator++(int) {
45 CtorDtorIterator Temp = *this;
46 ++I;
47 return Temp;
48}
49
50CtorDtorIterator::Element CtorDtorIterator::operator*() const {
51 ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(I));
4
←
Assuming the object is a 'ConstantStruct'
→
52 assert(CS && "Unrecognized type in llvm.global_ctors/llvm.global_dtors")((void)0);
53
54 Constant *FuncC = CS->getOperand(1);
55 Function *Func = nullptr;
5
←
'Func' initialized to a null pointer value
→
56
57 // Extract function pointer, pulling off any casts.
58 while (FuncC) {
6
←
Loop condition is false. Execution continues on line 73
→
59 if (Function *F = dyn_cast_or_null<Function>(FuncC)) {
60 Func = F;
61 break;
62 } else if (ConstantExpr *CE = dyn_cast_or_null<ConstantExpr>(FuncC)) {
63 if (CE->isCast())
64 FuncC = dyn_cast_or_null<ConstantExpr>(CE->getOperand(0));
65 else
66 break;
67 } else {
68 // This isn't anything we recognize. Bail out with Func left set to null.
69 break;
70 }
71 }
72
73 auto *Priority = cast<ConstantInt>(CS->getOperand(0));
74 Value *Data = CS->getNumOperands() == 3 ? CS->getOperand(2) : nullptr;
7
←
Assuming the condition is false
→
8
←
'?' condition is false
→
75 if (Data
8.1
'Data' is null
8.1
'Data' is null
 && !isa<GlobalValue>(Data))
76 Data = nullptr;
77 return Element(Priority->getZExtValue(), Func, Data);
9
←
Passing null pointer value via 2nd parameter 'Func'
→
10
←
Calling constructor for 'Element'
→
12
←
Returning from constructor for 'Element'
→
78}
79
80iterator_range<CtorDtorIterator> getConstructors(const Module &M) {
81 const GlobalVariable *CtorsList = M.getNamedGlobal("llvm.global_ctors");
82 return make_range(CtorDtorIterator(CtorsList, false),
83 CtorDtorIterator(CtorsList, true));
84}
85
86iterator_range<CtorDtorIterator> getDestructors(const Module &M) {
87 const GlobalVariable *DtorsList = M.getNamedGlobal("llvm.global_dtors");
88 return make_range(CtorDtorIterator(DtorsList, false),
89 CtorDtorIterator(DtorsList, true));
90}
91
92bool StaticInitGVIterator::isStaticInitGlobal(GlobalValue &GV) {
93 if (GV.isDeclaration())
94 return false;
95
96 if (GV.hasName() && (GV.getName() == "llvm.global_ctors" ||
97 GV.getName() == "llvm.global_dtors"))
98 return true;
99
100 if (ObjFmt == Triple::MachO) {
101 // FIXME: These section checks are too strict: We should match first and
102 // second word split by comma.
103 if (GV.hasSection() &&
104 (GV.getSection().startswith("__DATA,__objc_classlist") ||
105 GV.getSection().startswith("__DATA,__objc_selrefs")))
106 return true;
107 }
108
109 return false;
110}
111
112void CtorDtorRunner::add(iterator_range<CtorDtorIterator> CtorDtors) {
113 if (CtorDtors.empty())
1
Assuming the condition is false
→
2
←
Taking false branch
→
114 return;
115
116 MangleAndInterner Mangle(
117 JD.getExecutionSession(),
118 (*CtorDtors.begin()).Func->getParent()->getDataLayout());
3
←
Calling 'CtorDtorIterator::operator*'
→
13
←
Returning from 'CtorDtorIterator::operator*'
→
14
←
Called C++ object pointer is null
119
120 for (auto CtorDtor : CtorDtors) {
121 assert(CtorDtor.Func && CtorDtor.Func->hasName() &&((void)0)
122 "Ctor/Dtor function must be named to be runnable under the JIT")((void)0);
123
124 // FIXME: Maybe use a symbol promoter here instead.
125 if (CtorDtor.Func->hasLocalLinkage()) {
126 CtorDtor.Func->setLinkage(GlobalValue::ExternalLinkage);
127 CtorDtor.Func->setVisibility(GlobalValue::HiddenVisibility);
128 }
129
130 if (CtorDtor.Data && cast<GlobalValue>(CtorDtor.Data)->isDeclaration()) {
131 dbgs() << " Skipping because why now?\n";
132 continue;
133 }
134
135 CtorDtorsByPriority[CtorDtor.Priority].push_back(
136 Mangle(CtorDtor.Func->getName()));
137 }
138}
139
140Error CtorDtorRunner::run() {
141 using CtorDtorTy = void (*)();
142
143 SymbolLookupSet LookupSet;
144 for (auto &KV : CtorDtorsByPriority)
145 for (auto &Name : KV.second)
146 LookupSet.add(Name);
147 assert(!LookupSet.containsDuplicates() &&((void)0)
148 "Ctor/Dtor list contains duplicates")((void)0);
149
150 auto &ES = JD.getExecutionSession();
151 if (auto CtorDtorMap = ES.lookup(
152 makeJITDylibSearchOrder(&JD, JITDylibLookupFlags::MatchAllSymbols),
153 std::move(LookupSet))) {
154 for (auto &KV : CtorDtorsByPriority) {
155 for (auto &Name : KV.second) {
156 assert(CtorDtorMap->count(Name) && "No entry for Name")((void)0);
157 auto CtorDtor = reinterpret_cast<CtorDtorTy>(
158 static_cast<uintptr_t>((*CtorDtorMap)[Name].getAddress()));
159 CtorDtor();
160 }
161 }
162 CtorDtorsByPriority.clear();
163 return Error::success();
164 } else
165 return CtorDtorMap.takeError();
166}
167
168void LocalCXXRuntimeOverridesBase::runDestructors() {
169 auto& CXXDestructorDataPairs = DSOHandleOverride;
170 for (auto &P : CXXDestructorDataPairs)
171 P.first(P.second);
172 CXXDestructorDataPairs.clear();
173}
174
175int LocalCXXRuntimeOverridesBase::CXAAtExitOverride(DestructorPtr Destructor,
176 void *Arg,
177 void *DSOHandle) {
178 auto& CXXDestructorDataPairs =
179 *reinterpret_cast<CXXDestructorDataPairList*>(DSOHandle);
180 CXXDestructorDataPairs.push_back(std::make_pair(Destructor, Arg));
181 return 0;
182}
183
184Error LocalCXXRuntimeOverrides::enable(JITDylib &JD,
185 MangleAndInterner &Mangle) {
186 SymbolMap RuntimeInterposes;
187 RuntimeInterposes[Mangle("__dso_handle")] =
188 JITEvaluatedSymbol(toTargetAddress(&DSOHandleOverride),
189 JITSymbolFlags::Exported);
190 RuntimeInterposes[Mangle("__cxa_atexit")] =
191 JITEvaluatedSymbol(toTargetAddress(&CXAAtExitOverride),
192 JITSymbolFlags::Exported);
193
194 return JD.define(absoluteSymbols(std::move(RuntimeInterposes)));
195}
196
197void ItaniumCXAAtExitSupport::registerAtExit(void (*F)(void *), void *Ctx,
198 void *DSOHandle) {
199 std::lock_guard<std::mutex> Lock(AtExitsMutex);
200 AtExitRecords[DSOHandle].push_back({F, Ctx});
201}
202
203void ItaniumCXAAtExitSupport::runAtExits(void *DSOHandle) {
204 std::vector<AtExitRecord> AtExitsToRun;
205
206 {
207 std::lock_guard<std::mutex> Lock(AtExitsMutex);
208 auto I = AtExitRecords.find(DSOHandle);
209 if (I != AtExitRecords.end()) {
210 AtExitsToRun = std::move(I->second);
211 AtExitRecords.erase(I);
212 }
213 }
214
215 while (!AtExitsToRun.empty()) {
216 AtExitsToRun.back().F(AtExitsToRun.back().Ctx);
217 AtExitsToRun.pop_back();
218 }
219}
220
221DynamicLibrarySearchGenerator::DynamicLibrarySearchGenerator(
222 sys::DynamicLibrary Dylib, char GlobalPrefix, SymbolPredicate Allow)
223 : Dylib(std::move(Dylib)), Allow(std::move(Allow)),
224 GlobalPrefix(GlobalPrefix) {}
225
226Expected<std::unique_ptr<DynamicLibrarySearchGenerator>>
227DynamicLibrarySearchGenerator::Load(const char *FileName, char GlobalPrefix,
228 SymbolPredicate Allow) {
229 std::string ErrMsg;
230 auto Lib = sys::DynamicLibrary::getPermanentLibrary(FileName, &ErrMsg);
231 if (!Lib.isValid())
232 return make_error<StringError>(std::move(ErrMsg), inconvertibleErrorCode());
233 return std::make_unique<DynamicLibrarySearchGenerator>(
234 std::move(Lib), GlobalPrefix, std::move(Allow));
235}
236
237Error DynamicLibrarySearchGenerator::tryToGenerate(
238 LookupState &LS, LookupKind K, JITDylib &JD,
239 JITDylibLookupFlags JDLookupFlags, const SymbolLookupSet &Symbols) {
240 orc::SymbolMap NewSymbols;
241
242 bool HasGlobalPrefix = (GlobalPrefix != '\0');
243
244 for (auto &KV : Symbols) {
245 auto &Name = KV.first;
246
247 if ((*Name).empty())
248 continue;
249
250 if (Allow && !Allow(Name))
251 continue;
252
253 if (HasGlobalPrefix && (*Name).front() != GlobalPrefix)
254 continue;
255
256 std::string Tmp((*Name).data() + HasGlobalPrefix,
257 (*Name).size() - HasGlobalPrefix);
258 if (void *Addr = Dylib.getAddressOfSymbol(Tmp.c_str())) {
259 NewSymbols[Name] = JITEvaluatedSymbol(
260 static_cast<JITTargetAddress>(reinterpret_cast<uintptr_t>(Addr)),
261 JITSymbolFlags::Exported);
262 }
263 }
264
265 if (NewSymbols.empty())
266 return Error::success();
267
268 return JD.define(absoluteSymbols(std::move(NewSymbols)));
269}
270
271Expected<std::unique_ptr<StaticLibraryDefinitionGenerator>>
272StaticLibraryDefinitionGenerator::Load(ObjectLayer &L, const char *FileName) {
273 auto ArchiveBuffer = errorOrToExpected(MemoryBuffer::getFile(FileName));
274
275 if (!ArchiveBuffer)
276 return ArchiveBuffer.takeError();
277
278 return Create(L, std::move(*ArchiveBuffer));
279}
280
281Expected<std::unique_ptr<StaticLibraryDefinitionGenerator>>
282StaticLibraryDefinitionGenerator::Load(ObjectLayer &L, const char *FileName,
283 const Triple &TT) {
284 auto B = object::createBinary(FileName);
285 if (!B)
286 return B.takeError();
287
288 // If this is a regular archive then create an instance from it.
289 if (isa<object::Archive>(B->getBinary()))
290 return Create(L, std::move(B->takeBinary().second));
291
292 // If this is a universal binary then search for a slice matching the given
293 // Triple.
294 if (auto *UB = cast<object::MachOUniversalBinary>(B->getBinary())) {
295 for (const auto &Obj : UB->objects()) {
296 auto ObjTT = Obj.getTriple();
297 if (ObjTT.getArch() == TT.getArch() &&
298 ObjTT.getSubArch() == TT.getSubArch() &&
299 (TT.getVendor() == Triple::UnknownVendor ||
300 ObjTT.getVendor() == TT.getVendor())) {
301 // We found a match. Create an instance from a buffer covering this
302 // slice.
303 auto SliceBuffer = MemoryBuffer::getFileSlice(FileName, Obj.getSize(),
304 Obj.getOffset());
305 if (!SliceBuffer)
306 return make_error<StringError>(
307 Twine("Could not create buffer for ") + TT.str() + " slice of " +
308 FileName + ": [ " + formatv("{0:x}", Obj.getOffset()) +
309 " .. " + formatv("{0:x}", Obj.getOffset() + Obj.getSize()) +
310 ": " + SliceBuffer.getError().message(),
311 SliceBuffer.getError());
312 return Create(L, std::move(*SliceBuffer));
313 }
314 }
315
316 return make_error<StringError>(Twine("Universal binary ") + FileName +
317 " does not contain a slice for " +
318 TT.str(),
319 inconvertibleErrorCode());
320 }
321
322 return make_error<StringError>(Twine("Unrecognized file type for ") +
323 FileName,
324 inconvertibleErrorCode());
325}
326
327Expected<std::unique_ptr<StaticLibraryDefinitionGenerator>>
328StaticLibraryDefinitionGenerator::Create(
329 ObjectLayer &L, std::unique_ptr<MemoryBuffer> ArchiveBuffer) {
330 Error Err = Error::success();
331
332 std::unique_ptr<StaticLibraryDefinitionGenerator> ADG(
333 new StaticLibraryDefinitionGenerator(L, std::move(ArchiveBuffer), Err));
334
335 if (Err)
336 return std::move(Err);
337
338 return std::move(ADG);
339}
340
341Error StaticLibraryDefinitionGenerator::tryToGenerate(
342 LookupState &LS, LookupKind K, JITDylib &JD,
343 JITDylibLookupFlags JDLookupFlags, const SymbolLookupSet &Symbols) {
344
345 // Don't materialize symbols from static archives unless this is a static
346 // lookup.
347 if (K != LookupKind::Static)
348 return Error::success();
349
350 // Bail out early if we've already freed the archive.
351 if (!Archive)
352 return Error::success();
353
354 DenseSet<std::pair<StringRef, StringRef>> ChildBufferInfos;
355
356 for (const auto &KV : Symbols) {
357 const auto &Name = KV.first;
358 auto Child = Archive->findSym(*Name);
359 if (!Child)
360 return Child.takeError();
361 if (*Child == None)
362 continue;
363 auto ChildBuffer = (*Child)->getMemoryBufferRef();
364 if (!ChildBuffer)
365 return ChildBuffer.takeError();
366 ChildBufferInfos.insert(
367 {ChildBuffer->getBuffer(), ChildBuffer->getBufferIdentifier()});
368 }
369
370 for (auto ChildBufferInfo : ChildBufferInfos) {
371 MemoryBufferRef ChildBufferRef(ChildBufferInfo.first,
372 ChildBufferInfo.second);
373
374 if (auto Err = L.add(JD, MemoryBuffer::getMemBuffer(ChildBufferRef, false)))
375 return Err;
376 }
377
378 return Error::success();
379}
380
381StaticLibraryDefinitionGenerator::StaticLibraryDefinitionGenerator(
382 ObjectLayer &L, std::unique_ptr<MemoryBuffer> ArchiveBuffer, Error &Err)
383 : L(L), ArchiveBuffer(std::move(ArchiveBuffer)),
384 Archive(std::make_unique<object::Archive>(*this->ArchiveBuffer, Err)) {}
385
386} // End namespace orc.
387} // End namespace llvm.
←

/usr/src/gnu/usr.bin/clang/libLLVM/../../../llvm/llvm/include/llvm/ExecutionEngine/Orc/ExecutionUtils.h

1//===- ExecutionUtils.h - Utilities for executing code in Orc ---*- C++ -*-===//
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// Contains utilities for executing code in Orc.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_EXECUTIONENGINE_ORC_EXECUTIONUTILS_H
14#define LLVM_EXECUTIONENGINE_ORC_EXECUTIONUTILS_H
15
16#include "llvm/ADT/StringMap.h"
17#include "llvm/ADT/iterator_range.h"
18#include "llvm/ExecutionEngine/JITSymbol.h"
19#include "llvm/ExecutionEngine/Orc/Core.h"
20#include "llvm/ExecutionEngine/Orc/Mangling.h"
21#include "llvm/ExecutionEngine/Orc/Shared/OrcError.h"
22#include "llvm/ExecutionEngine/RuntimeDyld.h"
23#include "llvm/Object/Archive.h"
24#include "llvm/Support/DynamicLibrary.h"
25#include <algorithm>
26#include <cstdint>
27#include <utility>
28#include <vector>
29
30namespace llvm {
31
32class ConstantArray;
33class GlobalVariable;
34class Function;
35class Module;
36class TargetMachine;
37class Value;
38
39namespace orc {
40
41class ObjectLayer;
42
43/// This iterator provides a convenient way to iterate over the elements
44/// of an llvm.global_ctors/llvm.global_dtors instance.
45///
46/// The easiest way to get hold of instances of this class is to use the
47/// getConstructors/getDestructors functions.
48class CtorDtorIterator {
49public:
50 /// Accessor for an element of the global_ctors/global_dtors array.
51 ///
52 /// This class provides a read-only view of the element with any casts on
53 /// the function stripped away.
54 struct Element {
55 Element(unsigned Priority, Function *Func, Value *Data)
56 : Priority(Priority), Func(Func), Data(Data) {}
11
←
Null pointer value stored to field 'Func'
→
57
58 unsigned Priority;
59 Function *Func;
60 Value *Data;
61 };
62
63 /// Construct an iterator instance. If End is true then this iterator
64 /// acts as the end of the range, otherwise it is the beginning.
65 CtorDtorIterator(const GlobalVariable *GV, bool End);
66
67 /// Test iterators for equality.
68 bool operator==(const CtorDtorIterator &Other) const;
69
70 /// Test iterators for inequality.
71 bool operator!=(const CtorDtorIterator &Other) const;
72
73 /// Pre-increment iterator.
74 CtorDtorIterator& operator++();
75
76 /// Post-increment iterator.
77 CtorDtorIterator operator++(int);
78
79 /// Dereference iterator. The resulting value provides a read-only view
80 /// of this element of the global_ctors/global_dtors list.
81 Element operator*() const;
82
83private:
84 const ConstantArray *InitList;
85 unsigned I;
86};
87
88/// Create an iterator range over the entries of the llvm.global_ctors
89/// array.
90iterator_range<CtorDtorIterator> getConstructors(const Module &M);
91
92/// Create an iterator range over the entries of the llvm.global_ctors
93/// array.
94iterator_range<CtorDtorIterator> getDestructors(const Module &M);
95
96/// This iterator provides a convenient way to iterate over GlobalValues that
97/// have initialization effects.
98class StaticInitGVIterator {
99public:
100 StaticInitGVIterator() = default;
101
102 StaticInitGVIterator(Module &M)
103 : I(M.global_values().begin()), E(M.global_values().end()),
104 ObjFmt(Triple(M.getTargetTriple()).getObjectFormat()) {
105 if (I != E) {
106 if (!isStaticInitGlobal(*I))
107 moveToNextStaticInitGlobal();
108 } else
109 I = E = Module::global_value_iterator();
110 }
111
112 bool operator==(const StaticInitGVIterator &O) const { return I == O.I; }
113 bool operator!=(const StaticInitGVIterator &O) const { return I != O.I; }
114
115 StaticInitGVIterator &operator++() {
116 assert(I != E && "Increment past end of range")((void)0);
117 moveToNextStaticInitGlobal();
118 return *this;
119 }
120
121 GlobalValue &operator*() { return *I; }
122
123private:
124 bool isStaticInitGlobal(GlobalValue &GV);
125 void moveToNextStaticInitGlobal() {
126 ++I;
127 while (I != E && !isStaticInitGlobal(*I))
128 ++I;
129 if (I == E)
130 I = E = Module::global_value_iterator();
131 }
132
133 Module::global_value_iterator I, E;
134 Triple::ObjectFormatType ObjFmt;
135};
136
137/// Create an iterator range over the GlobalValues that contribute to static
138/// initialization.
139inline iterator_range<StaticInitGVIterator> getStaticInitGVs(Module &M) {
140 return make_range(StaticInitGVIterator(M), StaticInitGVIterator());
141}
142
143class CtorDtorRunner {
144public:
145 CtorDtorRunner(JITDylib &JD) : JD(JD) {}
146 void add(iterator_range<CtorDtorIterator> CtorDtors);
147 Error run();
148
149private:
150 using CtorDtorList = std::vector<SymbolStringPtr>;
151 using CtorDtorPriorityMap = std::map<unsigned, CtorDtorList>;
152
153 JITDylib &JD;
154 CtorDtorPriorityMap CtorDtorsByPriority;
155};
156
157/// Support class for static dtor execution. For hosted (in-process) JITs
158/// only!
159///
160/// If a __cxa_atexit function isn't found C++ programs that use static
161/// destructors will fail to link. However, we don't want to use the host
162/// process's __cxa_atexit, because it will schedule JIT'd destructors to run
163/// after the JIT has been torn down, which is no good. This class makes it easy
164/// to override __cxa_atexit (and the related __dso_handle).
165///
166/// To use, clients should manually call searchOverrides from their symbol
167/// resolver. This should generally be done after attempting symbol resolution
168/// inside the JIT, but before searching the host process's symbol table. When
169/// the client determines that destructors should be run (generally at JIT
170/// teardown or after a return from main), the runDestructors method should be
171/// called.
172class LocalCXXRuntimeOverridesBase {
173public:
174 /// Run any destructors recorded by the overriden __cxa_atexit function
175 /// (CXAAtExitOverride).
176 void runDestructors();
177
178protected:
179 template <typename PtrTy> JITTargetAddress toTargetAddress(PtrTy *P) {
180 return static_cast<JITTargetAddress>(reinterpret_cast<uintptr_t>(P));
181 }
182
183 using DestructorPtr = void (*)(void *);
184 using CXXDestructorDataPair = std::pair<DestructorPtr, void *>;
185 using CXXDestructorDataPairList = std::vector<CXXDestructorDataPair>;
186 CXXDestructorDataPairList DSOHandleOverride;
187 static int CXAAtExitOverride(DestructorPtr Destructor, void *Arg,
188 void *DSOHandle);
189};
190
191class LocalCXXRuntimeOverrides : public LocalCXXRuntimeOverridesBase {
192public:
193 Error enable(JITDylib &JD, MangleAndInterner &Mangler);
194};
195
196/// An interface for Itanium __cxa_atexit interposer implementations.
197class ItaniumCXAAtExitSupport {
198public:
199 struct AtExitRecord {
200 void (*F)(void *);
201 void *Ctx;
202 };
203
204 void registerAtExit(void (*F)(void *), void *Ctx, void *DSOHandle);
205 void runAtExits(void *DSOHandle);
206
207private:
208 std::mutex AtExitsMutex;
209 DenseMap<void *, std::vector<AtExitRecord>> AtExitRecords;
210};
211
212/// A utility class to expose symbols found via dlsym to the JIT.
213///
214/// If an instance of this class is attached to a JITDylib as a fallback
215/// definition generator, then any symbol found in the given DynamicLibrary that
216/// passes the 'Allow' predicate will be added to the JITDylib.
217class DynamicLibrarySearchGenerator : public DefinitionGenerator {
218public:
219 using SymbolPredicate = std::function<bool(const SymbolStringPtr &)>;
220
221 /// Create a DynamicLibrarySearchGenerator that searches for symbols in the
222 /// given sys::DynamicLibrary.
223 ///
224 /// If the Allow predicate is given then only symbols matching the predicate
225 /// will be searched for. If the predicate is not given then all symbols will
226 /// be searched for.
227 DynamicLibrarySearchGenerator(sys::DynamicLibrary Dylib, char GlobalPrefix,
228 SymbolPredicate Allow = SymbolPredicate());
229
230 /// Permanently loads the library at the given path and, on success, returns
231 /// a DynamicLibrarySearchGenerator that will search it for symbol definitions
232 /// in the library. On failure returns the reason the library failed to load.
233 static Expected<std::unique_ptr<DynamicLibrarySearchGenerator>>
234 Load(const char *FileName, char GlobalPrefix,
235 SymbolPredicate Allow = SymbolPredicate());
236
237 /// Creates a DynamicLibrarySearchGenerator that searches for symbols in
238 /// the current process.
239 static Expected<std::unique_ptr<DynamicLibrarySearchGenerator>>
240 GetForCurrentProcess(char GlobalPrefix,
241 SymbolPredicate Allow = SymbolPredicate()) {
242 return Load(nullptr, GlobalPrefix, std::move(Allow));
243 }
244
245 Error tryToGenerate(LookupState &LS, LookupKind K, JITDylib &JD,
246 JITDylibLookupFlags JDLookupFlags,
247 const SymbolLookupSet &Symbols) override;
248
249private:
250 sys::DynamicLibrary Dylib;
251 SymbolPredicate Allow;
252 char GlobalPrefix;
253};
254
255/// A utility class to expose symbols from a static library.
256///
257/// If an instance of this class is attached to a JITDylib as a fallback
258/// definition generator, then any symbol found in the archive will result in
259/// the containing object being added to the JITDylib.
260class StaticLibraryDefinitionGenerator : public DefinitionGenerator {
261public:
262 /// Try to create a StaticLibraryDefinitionGenerator from the given path.
263 ///
264 /// This call will succeed if the file at the given path is a static library
265 /// is a valid archive, otherwise it will return an error.
266 static Expected<std::unique_ptr<StaticLibraryDefinitionGenerator>>
267 Load(ObjectLayer &L, const char *FileName);
268
269 /// Try to create a StaticLibraryDefinitionGenerator from the given path.
270 ///
271 /// This call will succeed if the file at the given path is a static library
272 /// or a MachO universal binary containing a static library that is compatible
273 /// with the given triple. Otherwise it will return an error.
274 static Expected<std::unique_ptr<StaticLibraryDefinitionGenerator>>
275 Load(ObjectLayer &L, const char *FileName, const Triple &TT);
276
277 /// Try to create a StaticLibrarySearchGenerator from the given memory buffer.
278 /// This call will succeed if the buffer contains a valid archive, otherwise
279 /// it will return an error.
280 static Expected<std::unique_ptr<StaticLibraryDefinitionGenerator>>
281 Create(ObjectLayer &L, std::unique_ptr<MemoryBuffer> ArchiveBuffer);
282
283 Error tryToGenerate(LookupState &LS, LookupKind K, JITDylib &JD,
284 JITDylibLookupFlags JDLookupFlags,
285 const SymbolLookupSet &Symbols) override;
286
287private:
288 StaticLibraryDefinitionGenerator(ObjectLayer &L,
289 std::unique_ptr<MemoryBuffer> ArchiveBuffer,
290 Error &Err);
291
292 ObjectLayer &L;
293 std::unique_ptr<MemoryBuffer> ArchiveBuffer;
294 std::unique_ptr<object::Archive> Archive;
295};
296
297} // end namespace orc
298} // end namespace llvm
299
300#endif // LLVM_EXECUTIONENGINE_ORC_EXECUTIONUTILS_H