Bug Summary

File:llvm/include/llvm/ADT/FunctionExtras.h
Warning:line 142, column 5
Undefined or garbage value returned to caller

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name RuntimeDyld.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 -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mthread-model posix -mframe-pointer=none -fmath-errno -fno-rounding-math -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-10/lib/clang/10.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/build-llvm/lib/ExecutionEngine/RuntimeDyld -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/build-llvm/include -I /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-10/lib/clang/10.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/build-llvm/lib/ExecutionEngine/RuntimeDyld -fdebug-prefix-map=/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2019-12-07-102640-14763-1 -x c++ /build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp

/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp

1//===-- RuntimeDyld.cpp - Run-time dynamic linker for MC-JIT ----*- 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// Implementation of the MC-JIT runtime dynamic linker.
10//
11//===----------------------------------------------------------------------===//
12
13#include "llvm/ExecutionEngine/RuntimeDyld.h"
14#include "RuntimeDyldCOFF.h"
15#include "RuntimeDyldELF.h"
16#include "RuntimeDyldImpl.h"
17#include "RuntimeDyldMachO.h"
18#include "llvm/Object/COFF.h"
19#include "llvm/Object/ELFObjectFile.h"
20#include "llvm/Support/Alignment.h"
21#include "llvm/Support/MSVCErrorWorkarounds.h"
22#include "llvm/Support/ManagedStatic.h"
23#include "llvm/Support/MathExtras.h"
24#include <mutex>
25
26#include <future>
27
28using namespace llvm;
29using namespace llvm::object;
30
31#define DEBUG_TYPE"dyld" "dyld"
32
33namespace {
34
35enum RuntimeDyldErrorCode {
36 GenericRTDyldError = 1
37};
38
39// FIXME: This class is only here to support the transition to llvm::Error. It
40// will be removed once this transition is complete. Clients should prefer to
41// deal with the Error value directly, rather than converting to error_code.
42class RuntimeDyldErrorCategory : public std::error_category {
43public:
44 const char *name() const noexcept override { return "runtimedyld"; }
45
46 std::string message(int Condition) const override {
47 switch (static_cast<RuntimeDyldErrorCode>(Condition)) {
48 case GenericRTDyldError: return "Generic RuntimeDyld error";
49 }
50 llvm_unreachable("Unrecognized RuntimeDyldErrorCode")::llvm::llvm_unreachable_internal("Unrecognized RuntimeDyldErrorCode"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 50)
;
51 }
52};
53
54static ManagedStatic<RuntimeDyldErrorCategory> RTDyldErrorCategory;
55
56}
57
58char RuntimeDyldError::ID = 0;
59
60void RuntimeDyldError::log(raw_ostream &OS) const {
61 OS << ErrMsg << "\n";
62}
63
64std::error_code RuntimeDyldError::convertToErrorCode() const {
65 return std::error_code(GenericRTDyldError, *RTDyldErrorCategory);
66}
67
68// Empty out-of-line virtual destructor as the key function.
69RuntimeDyldImpl::~RuntimeDyldImpl() {}
70
71// Pin LoadedObjectInfo's vtables to this file.
72void RuntimeDyld::LoadedObjectInfo::anchor() {}
73
74namespace llvm {
75
76void RuntimeDyldImpl::registerEHFrames() {}
77
78void RuntimeDyldImpl::deregisterEHFrames() {
79 MemMgr.deregisterEHFrames();
80}
81
82#ifndef NDEBUG
83static void dumpSectionMemory(const SectionEntry &S, StringRef State) {
84 dbgs() << "----- Contents of section " << S.getName() << " " << State
85 << " -----";
86
87 if (S.getAddress() == nullptr) {
88 dbgs() << "\n <section not emitted>\n";
89 return;
90 }
91
92 const unsigned ColsPerRow = 16;
93
94 uint8_t *DataAddr = S.getAddress();
95 uint64_t LoadAddr = S.getLoadAddress();
96
97 unsigned StartPadding = LoadAddr & (ColsPerRow - 1);
98 unsigned BytesRemaining = S.getSize();
99
100 if (StartPadding) {
101 dbgs() << "\n" << format("0x%016" PRIx64"l" "x",
102 LoadAddr & ~(uint64_t)(ColsPerRow - 1)) << ":";
103 while (StartPadding--)
104 dbgs() << " ";
105 }
106
107 while (BytesRemaining > 0) {
108 if ((LoadAddr & (ColsPerRow - 1)) == 0)
109 dbgs() << "\n" << format("0x%016" PRIx64"l" "x", LoadAddr) << ":";
110
111 dbgs() << " " << format("%02x", *DataAddr);
112
113 ++DataAddr;
114 ++LoadAddr;
115 --BytesRemaining;
116 }
117
118 dbgs() << "\n";
119}
120#endif
121
122// Resolve the relocations for all symbols we currently know about.
123void RuntimeDyldImpl::resolveRelocations() {
124 std::lock_guard<sys::Mutex> locked(lock);
125
126 // Print out the sections prior to relocation.
127 LLVM_DEBUG(for (int i = 0, e = Sections.size(); i != e; ++i)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { for (int i = 0, e = Sections.size(); i != e; ++i)
dumpSectionMemory(Sections[i], "before relocations");; } } while
(false)
128 dumpSectionMemory(Sections[i], "before relocations");)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { for (int i = 0, e = Sections.size(); i != e; ++i)
dumpSectionMemory(Sections[i], "before relocations");; } } while
(false)
;
129
130 // First, resolve relocations associated with external symbols.
131 if (auto Err = resolveExternalSymbols()) {
132 HasError = true;
133 ErrorStr = toString(std::move(Err));
134 }
135
136 resolveLocalRelocations();
137
138 // Print out sections after relocation.
139 LLVM_DEBUG(for (int i = 0, e = Sections.size(); i != e; ++i)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { for (int i = 0, e = Sections.size(); i != e; ++i)
dumpSectionMemory(Sections[i], "after relocations");; } } while
(false)
140 dumpSectionMemory(Sections[i], "after relocations");)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { for (int i = 0, e = Sections.size(); i != e; ++i)
dumpSectionMemory(Sections[i], "after relocations");; } } while
(false)
;
141}
142
143void RuntimeDyldImpl::resolveLocalRelocations() {
144 // Iterate over all outstanding relocations
145 for (auto it = Relocations.begin(), e = Relocations.end(); it != e; ++it) {
146 // The Section here (Sections[i]) refers to the section in which the
147 // symbol for the relocation is located. The SectionID in the relocation
148 // entry provides the section to which the relocation will be applied.
149 int Idx = it->first;
150 uint64_t Addr = Sections[Idx].getLoadAddress();
151 LLVM_DEBUG(dbgs() << "Resolving relocations Section #" << Idx << "\t"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Resolving relocations Section #"
<< Idx << "\t" << format("%p", (uintptr_t)
Addr) << "\n"; } } while (false)
152 << format("%p", (uintptr_t)Addr) << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Resolving relocations Section #"
<< Idx << "\t" << format("%p", (uintptr_t)
Addr) << "\n"; } } while (false)
;
153 resolveRelocationList(it->second, Addr);
154 }
155 Relocations.clear();
156}
157
158void RuntimeDyldImpl::mapSectionAddress(const void *LocalAddress,
159 uint64_t TargetAddress) {
160 std::lock_guard<sys::Mutex> locked(lock);
161 for (unsigned i = 0, e = Sections.size(); i != e; ++i) {
162 if (Sections[i].getAddress() == LocalAddress) {
163 reassignSectionAddress(i, TargetAddress);
164 return;
165 }
166 }
167 llvm_unreachable("Attempting to remap address of unknown section!")::llvm::llvm_unreachable_internal("Attempting to remap address of unknown section!"
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 167)
;
168}
169
170static Error getOffset(const SymbolRef &Sym, SectionRef Sec,
171 uint64_t &Result) {
172 Expected<uint64_t> AddressOrErr = Sym.getAddress();
173 if (!AddressOrErr)
174 return AddressOrErr.takeError();
175 Result = *AddressOrErr - Sec.getAddress();
176 return Error::success();
177}
178
179Expected<RuntimeDyldImpl::ObjSectionToIDMap>
180RuntimeDyldImpl::loadObjectImpl(const object::ObjectFile &Obj) {
181 std::lock_guard<sys::Mutex> locked(lock);
182
183 // Save information about our target
184 Arch = (Triple::ArchType)Obj.getArch();
185 IsTargetLittleEndian = Obj.isLittleEndian();
186 setMipsABI(Obj);
187
188 // Compute the memory size required to load all sections to be loaded
189 // and pass this information to the memory manager
190 if (MemMgr.needsToReserveAllocationSpace()) {
191 uint64_t CodeSize = 0, RODataSize = 0, RWDataSize = 0;
192 uint32_t CodeAlign = 1, RODataAlign = 1, RWDataAlign = 1;
193 if (auto Err = computeTotalAllocSize(Obj,
194 CodeSize, CodeAlign,
195 RODataSize, RODataAlign,
196 RWDataSize, RWDataAlign))
197 return std::move(Err);
198 MemMgr.reserveAllocationSpace(CodeSize, CodeAlign, RODataSize, RODataAlign,
199 RWDataSize, RWDataAlign);
200 }
201
202 // Used sections from the object file
203 ObjSectionToIDMap LocalSections;
204
205 // Common symbols requiring allocation, with their sizes and alignments
206 CommonSymbolList CommonSymbolsToAllocate;
207
208 uint64_t CommonSize = 0;
209 uint32_t CommonAlign = 0;
210
211 // First, collect all weak and common symbols. We need to know if stronger
212 // definitions occur elsewhere.
213 JITSymbolResolver::LookupSet ResponsibilitySet;
214 {
215 JITSymbolResolver::LookupSet Symbols;
216 for (auto &Sym : Obj.symbols()) {
217 uint32_t Flags = Sym.getFlags();
218 if ((Flags & SymbolRef::SF_Common) || (Flags & SymbolRef::SF_Weak)) {
219 // Get symbol name.
220 if (auto NameOrErr = Sym.getName())
221 Symbols.insert(*NameOrErr);
222 else
223 return NameOrErr.takeError();
224 }
225 }
226
227 if (auto ResultOrErr = Resolver.getResponsibilitySet(Symbols))
228 ResponsibilitySet = std::move(*ResultOrErr);
229 else
230 return ResultOrErr.takeError();
231 }
232
233 // Parse symbols
234 LLVM_DEBUG(dbgs() << "Parse symbols:\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Parse symbols:\n"; } } while (false
)
;
235 for (symbol_iterator I = Obj.symbol_begin(), E = Obj.symbol_end(); I != E;
236 ++I) {
237 uint32_t Flags = I->getFlags();
238
239 // Skip undefined symbols.
240 if (Flags & SymbolRef::SF_Undefined)
241 continue;
242
243 // Get the symbol type.
244 object::SymbolRef::Type SymType;
245 if (auto SymTypeOrErr = I->getType())
246 SymType = *SymTypeOrErr;
247 else
248 return SymTypeOrErr.takeError();
249
250 // Get symbol name.
251 StringRef Name;
252 if (auto NameOrErr = I->getName())
253 Name = *NameOrErr;
254 else
255 return NameOrErr.takeError();
256
257 // Compute JIT symbol flags.
258 auto JITSymFlags = getJITSymbolFlags(*I);
259 if (!JITSymFlags)
260 return JITSymFlags.takeError();
261
262 // If this is a weak definition, check to see if there's a strong one.
263 // If there is, skip this symbol (we won't be providing it: the strong
264 // definition will). If there's no strong definition, make this definition
265 // strong.
266 if (JITSymFlags->isWeak() || JITSymFlags->isCommon()) {
267 // First check whether there's already a definition in this instance.
268 if (GlobalSymbolTable.count(Name))
269 continue;
270
271 // If we're not responsible for this symbol, skip it.
272 if (!ResponsibilitySet.count(Name))
273 continue;
274
275 // Otherwise update the flags on the symbol to make this definition
276 // strong.
277 if (JITSymFlags->isWeak())
278 *JITSymFlags &= ~JITSymbolFlags::Weak;
279 if (JITSymFlags->isCommon()) {
280 *JITSymFlags &= ~JITSymbolFlags::Common;
281 uint32_t Align = I->getAlignment();
282 uint64_t Size = I->getCommonSize();
283 if (!CommonAlign)
284 CommonAlign = Align;
285 CommonSize = alignTo(CommonSize, Align) + Size;
286 CommonSymbolsToAllocate.push_back(*I);
287 }
288 }
289
290 if (Flags & SymbolRef::SF_Absolute &&
291 SymType != object::SymbolRef::ST_File) {
292 uint64_t Addr = 0;
293 if (auto AddrOrErr = I->getAddress())
294 Addr = *AddrOrErr;
295 else
296 return AddrOrErr.takeError();
297
298 unsigned SectionID = AbsoluteSymbolSection;
299
300 LLVM_DEBUG(dbgs() << "\tType: " << SymType << " (absolute) Name: " << Namedo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "\tType: " << SymType <<
" (absolute) Name: " << Name << " SID: " <<
SectionID << " Offset: " << format("%p", (uintptr_t
)Addr) << " flags: " << Flags << "\n"; } } while
(false)
301 << " SID: " << SectionIDdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "\tType: " << SymType <<
" (absolute) Name: " << Name << " SID: " <<
SectionID << " Offset: " << format("%p", (uintptr_t
)Addr) << " flags: " << Flags << "\n"; } } while
(false)
302 << " Offset: " << format("%p", (uintptr_t)Addr)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "\tType: " << SymType <<
" (absolute) Name: " << Name << " SID: " <<
SectionID << " Offset: " << format("%p", (uintptr_t
)Addr) << " flags: " << Flags << "\n"; } } while
(false)
303 << " flags: " << Flags << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "\tType: " << SymType <<
" (absolute) Name: " << Name << " SID: " <<
SectionID << " Offset: " << format("%p", (uintptr_t
)Addr) << " flags: " << Flags << "\n"; } } while
(false)
;
304 GlobalSymbolTable[Name] = SymbolTableEntry(SectionID, Addr, *JITSymFlags);
305 } else if (SymType == object::SymbolRef::ST_Function ||
306 SymType == object::SymbolRef::ST_Data ||
307 SymType == object::SymbolRef::ST_Unknown ||
308 SymType == object::SymbolRef::ST_Other) {
309
310 section_iterator SI = Obj.section_end();
311 if (auto SIOrErr = I->getSection())
312 SI = *SIOrErr;
313 else
314 return SIOrErr.takeError();
315
316 if (SI == Obj.section_end())
317 continue;
318
319 // Get symbol offset.
320 uint64_t SectOffset;
321 if (auto Err = getOffset(*I, *SI, SectOffset))
322 return std::move(Err);
323
324 bool IsCode = SI->isText();
325 unsigned SectionID;
326 if (auto SectionIDOrErr =
327 findOrEmitSection(Obj, *SI, IsCode, LocalSections))
328 SectionID = *SectionIDOrErr;
329 else
330 return SectionIDOrErr.takeError();
331
332 LLVM_DEBUG(dbgs() << "\tType: " << SymType << " Name: " << Namedo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "\tType: " << SymType <<
" Name: " << Name << " SID: " << SectionID
<< " Offset: " << format("%p", (uintptr_t)SectOffset
) << " flags: " << Flags << "\n"; } } while
(false)
333 << " SID: " << SectionIDdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "\tType: " << SymType <<
" Name: " << Name << " SID: " << SectionID
<< " Offset: " << format("%p", (uintptr_t)SectOffset
) << " flags: " << Flags << "\n"; } } while
(false)
334 << " Offset: " << format("%p", (uintptr_t)SectOffset)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "\tType: " << SymType <<
" Name: " << Name << " SID: " << SectionID
<< " Offset: " << format("%p", (uintptr_t)SectOffset
) << " flags: " << Flags << "\n"; } } while
(false)
335 << " flags: " << Flags << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "\tType: " << SymType <<
" Name: " << Name << " SID: " << SectionID
<< " Offset: " << format("%p", (uintptr_t)SectOffset
) << " flags: " << Flags << "\n"; } } while
(false)
;
336 GlobalSymbolTable[Name] =
337 SymbolTableEntry(SectionID, SectOffset, *JITSymFlags);
338 }
339 }
340
341 // Allocate common symbols
342 if (auto Err = emitCommonSymbols(Obj, CommonSymbolsToAllocate, CommonSize,
343 CommonAlign))
344 return std::move(Err);
345
346 // Parse and process relocations
347 LLVM_DEBUG(dbgs() << "Parse relocations:\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Parse relocations:\n"; } } while
(false)
;
348 for (section_iterator SI = Obj.section_begin(), SE = Obj.section_end();
349 SI != SE; ++SI) {
350 StubMap Stubs;
351
352 Expected<section_iterator> RelSecOrErr = SI->getRelocatedSection();
353 if (!RelSecOrErr)
354 return RelSecOrErr.takeError();
355
356 section_iterator RelocatedSection = *RelSecOrErr;
357 if (RelocatedSection == SE)
358 continue;
359
360 relocation_iterator I = SI->relocation_begin();
361 relocation_iterator E = SI->relocation_end();
362
363 if (I == E && !ProcessAllSections)
364 continue;
365
366 bool IsCode = RelocatedSection->isText();
367 unsigned SectionID = 0;
368 if (auto SectionIDOrErr = findOrEmitSection(Obj, *RelocatedSection, IsCode,
369 LocalSections))
370 SectionID = *SectionIDOrErr;
371 else
372 return SectionIDOrErr.takeError();
373
374 LLVM_DEBUG(dbgs() << "\tSectionID: " << SectionID << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "\tSectionID: " << SectionID
<< "\n"; } } while (false)
;
375
376 for (; I != E;)
377 if (auto IOrErr = processRelocationRef(SectionID, I, Obj, LocalSections, Stubs))
378 I = *IOrErr;
379 else
380 return IOrErr.takeError();
381
382 // If there is a NotifyStubEmitted callback set, call it to register any
383 // stubs created for this section.
384 if (NotifyStubEmitted) {
385 StringRef FileName = Obj.getFileName();
386 StringRef SectionName = Sections[SectionID].getName();
387 for (auto &KV : Stubs) {
388
389 auto &VR = KV.first;
390 uint64_t StubAddr = KV.second;
391
392 // If this is a named stub, just call NotifyStubEmitted.
393 if (VR.SymbolName) {
394 NotifyStubEmitted(FileName, SectionName, VR.SymbolName, SectionID,
395 StubAddr);
396 continue;
397 }
398
399 // Otherwise we will have to try a reverse lookup on the globla symbol table.
400 for (auto &GSTMapEntry : GlobalSymbolTable) {
401 StringRef SymbolName = GSTMapEntry.first();
402 auto &GSTEntry = GSTMapEntry.second;
403 if (GSTEntry.getSectionID() == VR.SectionID &&
404 GSTEntry.getOffset() == VR.Offset) {
405 NotifyStubEmitted(FileName, SectionName, SymbolName, SectionID,
406 StubAddr);
407 break;
408 }
409 }
410 }
411 }
412 }
413
414 // Process remaining sections
415 if (ProcessAllSections) {
416 LLVM_DEBUG(dbgs() << "Process remaining sections:\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Process remaining sections:\n"; }
} while (false)
;
417 for (section_iterator SI = Obj.section_begin(), SE = Obj.section_end();
418 SI != SE; ++SI) {
419
420 /* Ignore already loaded sections */
421 if (LocalSections.find(*SI) != LocalSections.end())
422 continue;
423
424 bool IsCode = SI->isText();
425 if (auto SectionIDOrErr =
426 findOrEmitSection(Obj, *SI, IsCode, LocalSections))
427 LLVM_DEBUG(dbgs() << "\tSectionID: " << (*SectionIDOrErr) << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "\tSectionID: " << (*SectionIDOrErr
) << "\n"; } } while (false)
;
428 else
429 return SectionIDOrErr.takeError();
430 }
431 }
432
433 // Give the subclasses a chance to tie-up any loose ends.
434 if (auto Err = finalizeLoad(Obj, LocalSections))
435 return std::move(Err);
436
437// for (auto E : LocalSections)
438// llvm::dbgs() << "Added: " << E.first.getRawDataRefImpl() << " -> " << E.second << "\n";
439
440 return LocalSections;
441}
442
443// A helper method for computeTotalAllocSize.
444// Computes the memory size required to allocate sections with the given sizes,
445// assuming that all sections are allocated with the given alignment
446static uint64_t
447computeAllocationSizeForSections(std::vector<uint64_t> &SectionSizes,
448 uint64_t Alignment) {
449 uint64_t TotalSize = 0;
450 for (size_t Idx = 0, Cnt = SectionSizes.size(); Idx < Cnt; Idx++) {
451 uint64_t AlignedSize =
452 (SectionSizes[Idx] + Alignment - 1) / Alignment * Alignment;
453 TotalSize += AlignedSize;
454 }
455 return TotalSize;
456}
457
458static bool isRequiredForExecution(const SectionRef Section) {
459 const ObjectFile *Obj = Section.getObject();
460 if (isa<object::ELFObjectFileBase>(Obj))
461 return ELFSectionRef(Section).getFlags() & ELF::SHF_ALLOC;
462 if (auto *COFFObj = dyn_cast<object::COFFObjectFile>(Obj)) {
463 const coff_section *CoffSection = COFFObj->getCOFFSection(Section);
464 // Avoid loading zero-sized COFF sections.
465 // In PE files, VirtualSize gives the section size, and SizeOfRawData
466 // may be zero for sections with content. In Obj files, SizeOfRawData
467 // gives the section size, and VirtualSize is always zero. Hence
468 // the need to check for both cases below.
469 bool HasContent =
470 (CoffSection->VirtualSize > 0) || (CoffSection->SizeOfRawData > 0);
471 bool IsDiscardable =
472 CoffSection->Characteristics &
473 (COFF::IMAGE_SCN_MEM_DISCARDABLE | COFF::IMAGE_SCN_LNK_INFO);
474 return HasContent && !IsDiscardable;
475 }
476
477 assert(isa<MachOObjectFile>(Obj))((isa<MachOObjectFile>(Obj)) ? static_cast<void> (
0) : __assert_fail ("isa<MachOObjectFile>(Obj)", "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 477, __PRETTY_FUNCTION__))
;
478 return true;
479}
480
481static bool isReadOnlyData(const SectionRef Section) {
482 const ObjectFile *Obj = Section.getObject();
483 if (isa<object::ELFObjectFileBase>(Obj))
484 return !(ELFSectionRef(Section).getFlags() &
485 (ELF::SHF_WRITE | ELF::SHF_EXECINSTR));
486 if (auto *COFFObj = dyn_cast<object::COFFObjectFile>(Obj))
487 return ((COFFObj->getCOFFSection(Section)->Characteristics &
488 (COFF::IMAGE_SCN_CNT_INITIALIZED_DATA
489 | COFF::IMAGE_SCN_MEM_READ
490 | COFF::IMAGE_SCN_MEM_WRITE))
491 ==
492 (COFF::IMAGE_SCN_CNT_INITIALIZED_DATA
493 | COFF::IMAGE_SCN_MEM_READ));
494
495 assert(isa<MachOObjectFile>(Obj))((isa<MachOObjectFile>(Obj)) ? static_cast<void> (
0) : __assert_fail ("isa<MachOObjectFile>(Obj)", "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 495, __PRETTY_FUNCTION__))
;
496 return false;
497}
498
499static bool isZeroInit(const SectionRef Section) {
500 const ObjectFile *Obj = Section.getObject();
501 if (isa<object::ELFObjectFileBase>(Obj))
502 return ELFSectionRef(Section).getType() == ELF::SHT_NOBITS;
503 if (auto *COFFObj = dyn_cast<object::COFFObjectFile>(Obj))
504 return COFFObj->getCOFFSection(Section)->Characteristics &
505 COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA;
506
507 auto *MachO = cast<MachOObjectFile>(Obj);
508 unsigned SectionType = MachO->getSectionType(Section);
509 return SectionType == MachO::S_ZEROFILL ||
510 SectionType == MachO::S_GB_ZEROFILL;
511}
512
513// Compute an upper bound of the memory size that is required to load all
514// sections
515Error RuntimeDyldImpl::computeTotalAllocSize(const ObjectFile &Obj,
516 uint64_t &CodeSize,
517 uint32_t &CodeAlign,
518 uint64_t &RODataSize,
519 uint32_t &RODataAlign,
520 uint64_t &RWDataSize,
521 uint32_t &RWDataAlign) {
522 // Compute the size of all sections required for execution
523 std::vector<uint64_t> CodeSectionSizes;
524 std::vector<uint64_t> ROSectionSizes;
525 std::vector<uint64_t> RWSectionSizes;
526
527 // Collect sizes of all sections to be loaded;
528 // also determine the max alignment of all sections
529 for (section_iterator SI = Obj.section_begin(), SE = Obj.section_end();
530 SI != SE; ++SI) {
531 const SectionRef &Section = *SI;
532
533 bool IsRequired = isRequiredForExecution(Section) || ProcessAllSections;
534
535 // Consider only the sections that are required to be loaded for execution
536 if (IsRequired) {
537 uint64_t DataSize = Section.getSize();
538 uint64_t Alignment64 = Section.getAlignment();
539 unsigned Alignment = (unsigned)Alignment64 & 0xffffffffL;
540 bool IsCode = Section.isText();
541 bool IsReadOnly = isReadOnlyData(Section);
542
543 Expected<StringRef> NameOrErr = Section.getName();
544 if (!NameOrErr)
545 return NameOrErr.takeError();
546 StringRef Name = *NameOrErr;
547
548 uint64_t StubBufSize = computeSectionStubBufSize(Obj, Section);
549
550 uint64_t PaddingSize = 0;
551 if (Name == ".eh_frame")
552 PaddingSize += 4;
553 if (StubBufSize != 0)
554 PaddingSize += getStubAlignment() - 1;
555
556 uint64_t SectionSize = DataSize + PaddingSize + StubBufSize;
557
558 // The .eh_frame section (at least on Linux) needs an extra four bytes
559 // padded
560 // with zeroes added at the end. For MachO objects, this section has a
561 // slightly different name, so this won't have any effect for MachO
562 // objects.
563 if (Name == ".eh_frame")
564 SectionSize += 4;
565
566 if (!SectionSize)
567 SectionSize = 1;
568
569 if (IsCode) {
570 CodeAlign = std::max(CodeAlign, Alignment);
571 CodeSectionSizes.push_back(SectionSize);
572 } else if (IsReadOnly) {
573 RODataAlign = std::max(RODataAlign, Alignment);
574 ROSectionSizes.push_back(SectionSize);
575 } else {
576 RWDataAlign = std::max(RWDataAlign, Alignment);
577 RWSectionSizes.push_back(SectionSize);
578 }
579 }
580 }
581
582 // Compute Global Offset Table size. If it is not zero we
583 // also update alignment, which is equal to a size of a
584 // single GOT entry.
585 if (unsigned GotSize = computeGOTSize(Obj)) {
586 RWSectionSizes.push_back(GotSize);
587 RWDataAlign = std::max<uint32_t>(RWDataAlign, getGOTEntrySize());
588 }
589
590 // Compute the size of all common symbols
591 uint64_t CommonSize = 0;
592 uint32_t CommonAlign = 1;
593 for (symbol_iterator I = Obj.symbol_begin(), E = Obj.symbol_end(); I != E;
594 ++I) {
595 uint32_t Flags = I->getFlags();
596 if (Flags & SymbolRef::SF_Common) {
597 // Add the common symbols to a list. We'll allocate them all below.
598 uint64_t Size = I->getCommonSize();
599 uint32_t Align = I->getAlignment();
600 // If this is the first common symbol, use its alignment as the alignment
601 // for the common symbols section.
602 if (CommonSize == 0)
603 CommonAlign = Align;
604 CommonSize = alignTo(CommonSize, Align) + Size;
605 }
606 }
607 if (CommonSize != 0) {
608 RWSectionSizes.push_back(CommonSize);
609 RWDataAlign = std::max(RWDataAlign, CommonAlign);
610 }
611
612 // Compute the required allocation space for each different type of sections
613 // (code, read-only data, read-write data) assuming that all sections are
614 // allocated with the max alignment. Note that we cannot compute with the
615 // individual alignments of the sections, because then the required size
616 // depends on the order, in which the sections are allocated.
617 CodeSize = computeAllocationSizeForSections(CodeSectionSizes, CodeAlign);
618 RODataSize = computeAllocationSizeForSections(ROSectionSizes, RODataAlign);
619 RWDataSize = computeAllocationSizeForSections(RWSectionSizes, RWDataAlign);
620
621 return Error::success();
622}
623
624// compute GOT size
625unsigned RuntimeDyldImpl::computeGOTSize(const ObjectFile &Obj) {
626 size_t GotEntrySize = getGOTEntrySize();
627 if (!GotEntrySize)
628 return 0;
629
630 size_t GotSize = 0;
631 for (section_iterator SI = Obj.section_begin(), SE = Obj.section_end();
632 SI != SE; ++SI) {
633
634 for (const RelocationRef &Reloc : SI->relocations())
635 if (relocationNeedsGot(Reloc))
636 GotSize += GotEntrySize;
637 }
638
639 return GotSize;
640}
641
642// compute stub buffer size for the given section
643unsigned RuntimeDyldImpl::computeSectionStubBufSize(const ObjectFile &Obj,
644 const SectionRef &Section) {
645 unsigned StubSize = getMaxStubSize();
646 if (StubSize == 0) {
647 return 0;
648 }
649 // FIXME: this is an inefficient way to handle this. We should computed the
650 // necessary section allocation size in loadObject by walking all the sections
651 // once.
652 unsigned StubBufSize = 0;
653 for (section_iterator SI = Obj.section_begin(), SE = Obj.section_end();
654 SI != SE; ++SI) {
655
656 Expected<section_iterator> RelSecOrErr = SI->getRelocatedSection();
657 if (!RelSecOrErr)
658 report_fatal_error(toString(RelSecOrErr.takeError()));
659
660 section_iterator RelSecI = *RelSecOrErr;
661 if (!(RelSecI == Section))
662 continue;
663
664 for (const RelocationRef &Reloc : SI->relocations())
665 if (relocationNeedsStub(Reloc))
666 StubBufSize += StubSize;
667 }
668
669 // Get section data size and alignment
670 uint64_t DataSize = Section.getSize();
671 uint64_t Alignment64 = Section.getAlignment();
672
673 // Add stubbuf size alignment
674 unsigned Alignment = (unsigned)Alignment64 & 0xffffffffL;
675 unsigned StubAlignment = getStubAlignment();
676 unsigned EndAlignment = (DataSize | Alignment) & -(DataSize | Alignment);
677 if (StubAlignment > EndAlignment)
678 StubBufSize += StubAlignment - EndAlignment;
679 return StubBufSize;
680}
681
682uint64_t RuntimeDyldImpl::readBytesUnaligned(uint8_t *Src,
683 unsigned Size) const {
684 uint64_t Result = 0;
685 if (IsTargetLittleEndian) {
686 Src += Size - 1;
687 while (Size--)
688 Result = (Result << 8) | *Src--;
689 } else
690 while (Size--)
691 Result = (Result << 8) | *Src++;
692
693 return Result;
694}
695
696void RuntimeDyldImpl::writeBytesUnaligned(uint64_t Value, uint8_t *Dst,
697 unsigned Size) const {
698 if (IsTargetLittleEndian) {
699 while (Size--) {
700 *Dst++ = Value & 0xFF;
701 Value >>= 8;
702 }
703 } else {
704 Dst += Size - 1;
705 while (Size--) {
706 *Dst-- = Value & 0xFF;
707 Value >>= 8;
708 }
709 }
710}
711
712Expected<JITSymbolFlags>
713RuntimeDyldImpl::getJITSymbolFlags(const SymbolRef &SR) {
714 return JITSymbolFlags::fromObjectSymbol(SR);
715}
716
717Error RuntimeDyldImpl::emitCommonSymbols(const ObjectFile &Obj,
718 CommonSymbolList &SymbolsToAllocate,
719 uint64_t CommonSize,
720 uint32_t CommonAlign) {
721 if (SymbolsToAllocate.empty())
722 return Error::success();
723
724 // Allocate memory for the section
725 unsigned SectionID = Sections.size();
726 uint8_t *Addr = MemMgr.allocateDataSection(CommonSize, CommonAlign, SectionID,
727 "<common symbols>", false);
728 if (!Addr)
729 report_fatal_error("Unable to allocate memory for common symbols!");
730 uint64_t Offset = 0;
731 Sections.push_back(
732 SectionEntry("<common symbols>", Addr, CommonSize, CommonSize, 0));
733 memset(Addr, 0, CommonSize);
734
735 LLVM_DEBUG(dbgs() << "emitCommonSection SectionID: " << SectionIDdo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitCommonSection SectionID: " <<
SectionID << " new addr: " << format("%p", Addr)
<< " DataSize: " << CommonSize << "\n"; } }
while (false)
736 << " new addr: " << format("%p", Addr)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitCommonSection SectionID: " <<
SectionID << " new addr: " << format("%p", Addr)
<< " DataSize: " << CommonSize << "\n"; } }
while (false)
737 << " DataSize: " << CommonSize << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitCommonSection SectionID: " <<
SectionID << " new addr: " << format("%p", Addr)
<< " DataSize: " << CommonSize << "\n"; } }
while (false)
;
738
739 // Assign the address of each symbol
740 for (auto &Sym : SymbolsToAllocate) {
741 uint32_t Alignment = Sym.getAlignment();
742 uint64_t Size = Sym.getCommonSize();
743 StringRef Name;
744 if (auto NameOrErr = Sym.getName())
745 Name = *NameOrErr;
746 else
747 return NameOrErr.takeError();
748 if (Alignment) {
749 // This symbol has an alignment requirement.
750 uint64_t AlignOffset =
751 offsetToAlignment((uint64_t)Addr, Align(Alignment));
752 Addr += AlignOffset;
753 Offset += AlignOffset;
754 }
755 auto JITSymFlags = getJITSymbolFlags(Sym);
756
757 if (!JITSymFlags)
758 return JITSymFlags.takeError();
759
760 LLVM_DEBUG(dbgs() << "Allocating common symbol " << Name << " address "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Allocating common symbol " <<
Name << " address " << format("%p", Addr) <<
"\n"; } } while (false)
761 << format("%p", Addr) << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Allocating common symbol " <<
Name << " address " << format("%p", Addr) <<
"\n"; } } while (false)
;
762 GlobalSymbolTable[Name] =
763 SymbolTableEntry(SectionID, Offset, std::move(*JITSymFlags));
764 Offset += Size;
765 Addr += Size;
766 }
767
768 return Error::success();
769}
770
771Expected<unsigned>
772RuntimeDyldImpl::emitSection(const ObjectFile &Obj,
773 const SectionRef &Section,
774 bool IsCode) {
775 StringRef data;
776 uint64_t Alignment64 = Section.getAlignment();
777
778 unsigned Alignment = (unsigned)Alignment64 & 0xffffffffL;
779 unsigned PaddingSize = 0;
780 unsigned StubBufSize = 0;
781 bool IsRequired = isRequiredForExecution(Section);
782 bool IsVirtual = Section.isVirtual();
783 bool IsZeroInit = isZeroInit(Section);
784 bool IsReadOnly = isReadOnlyData(Section);
785 uint64_t DataSize = Section.getSize();
786
787 // An alignment of 0 (at least with ELF) is identical to an alignment of 1,
788 // while being more "polite". Other formats do not support 0-aligned sections
789 // anyway, so we should guarantee that the alignment is always at least 1.
790 Alignment = std::max(1u, Alignment);
791
792 Expected<StringRef> NameOrErr = Section.getName();
793 if (!NameOrErr)
794 return NameOrErr.takeError();
795 StringRef Name = *NameOrErr;
796
797 StubBufSize = computeSectionStubBufSize(Obj, Section);
798
799 // The .eh_frame section (at least on Linux) needs an extra four bytes padded
800 // with zeroes added at the end. For MachO objects, this section has a
801 // slightly different name, so this won't have any effect for MachO objects.
802 if (Name == ".eh_frame")
803 PaddingSize = 4;
804
805 uintptr_t Allocate;
806 unsigned SectionID = Sections.size();
807 uint8_t *Addr;
808 const char *pData = nullptr;
809
810 // If this section contains any bits (i.e. isn't a virtual or bss section),
811 // grab a reference to them.
812 if (!IsVirtual && !IsZeroInit) {
813 // In either case, set the location of the unrelocated section in memory,
814 // since we still process relocations for it even if we're not applying them.
815 if (Expected<StringRef> E = Section.getContents())
816 data = *E;
817 else
818 return E.takeError();
819 pData = data.data();
820 }
821
822 // If there are any stubs then the section alignment needs to be at least as
823 // high as stub alignment or padding calculations may by incorrect when the
824 // section is remapped.
825 if (StubBufSize != 0) {
826 Alignment = std::max(Alignment, getStubAlignment());
827 PaddingSize += getStubAlignment() - 1;
828 }
829
830 // Some sections, such as debug info, don't need to be loaded for execution.
831 // Process those only if explicitly requested.
832 if (IsRequired || ProcessAllSections) {
833 Allocate = DataSize + PaddingSize + StubBufSize;
834 if (!Allocate)
835 Allocate = 1;
836 Addr = IsCode ? MemMgr.allocateCodeSection(Allocate, Alignment, SectionID,
837 Name)
838 : MemMgr.allocateDataSection(Allocate, Alignment, SectionID,
839 Name, IsReadOnly);
840 if (!Addr)
841 report_fatal_error("Unable to allocate section memory!");
842
843 // Zero-initialize or copy the data from the image
844 if (IsZeroInit || IsVirtual)
845 memset(Addr, 0, DataSize);
846 else
847 memcpy(Addr, pData, DataSize);
848
849 // Fill in any extra bytes we allocated for padding
850 if (PaddingSize != 0) {
851 memset(Addr + DataSize, 0, PaddingSize);
852 // Update the DataSize variable to include padding.
853 DataSize += PaddingSize;
854
855 // Align DataSize to stub alignment if we have any stubs (PaddingSize will
856 // have been increased above to account for this).
857 if (StubBufSize > 0)
858 DataSize &= -(uint64_t)getStubAlignment();
859 }
860
861 LLVM_DEBUG(dbgs() << "emitSection SectionID: " << SectionID << " Name: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitSection SectionID: " <<
SectionID << " Name: " << Name << " obj addr: "
<< format("%p", pData) << " new addr: " <<
format("%p", Addr) << " DataSize: " << DataSize <<
" StubBufSize: " << StubBufSize << " Allocate: "
<< Allocate << "\n"; } } while (false)
862 << Name << " obj addr: " << format("%p", pData)do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitSection SectionID: " <<
SectionID << " Name: " << Name << " obj addr: "
<< format("%p", pData) << " new addr: " <<
format("%p", Addr) << " DataSize: " << DataSize <<
" StubBufSize: " << StubBufSize << " Allocate: "
<< Allocate << "\n"; } } while (false)
863 << " new addr: " << format("%p", Addr) << " DataSize: "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitSection SectionID: " <<
SectionID << " Name: " << Name << " obj addr: "
<< format("%p", pData) << " new addr: " <<
format("%p", Addr) << " DataSize: " << DataSize <<
" StubBufSize: " << StubBufSize << " Allocate: "
<< Allocate << "\n"; } } while (false)
864 << DataSize << " StubBufSize: " << StubBufSizedo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitSection SectionID: " <<
SectionID << " Name: " << Name << " obj addr: "
<< format("%p", pData) << " new addr: " <<
format("%p", Addr) << " DataSize: " << DataSize <<
" StubBufSize: " << StubBufSize << " Allocate: "
<< Allocate << "\n"; } } while (false)
865 << " Allocate: " << Allocate << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitSection SectionID: " <<
SectionID << " Name: " << Name << " obj addr: "
<< format("%p", pData) << " new addr: " <<
format("%p", Addr) << " DataSize: " << DataSize <<
" StubBufSize: " << StubBufSize << " Allocate: "
<< Allocate << "\n"; } } while (false)
;
866 } else {
867 // Even if we didn't load the section, we need to record an entry for it
868 // to handle later processing (and by 'handle' I mean don't do anything
869 // with these sections).
870 Allocate = 0;
871 Addr = nullptr;
872 LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitSection SectionID: " <<
SectionID << " Name: " << Name << " obj addr: "
<< format("%p", data.data()) << " new addr: 0" <<
" DataSize: " << DataSize << " StubBufSize: " <<
StubBufSize << " Allocate: " << Allocate <<
"\n"; } } while (false)
873 dbgs() << "emitSection SectionID: " << SectionID << " Name: " << Namedo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitSection SectionID: " <<
SectionID << " Name: " << Name << " obj addr: "
<< format("%p", data.data()) << " new addr: 0" <<
" DataSize: " << DataSize << " StubBufSize: " <<
StubBufSize << " Allocate: " << Allocate <<
"\n"; } } while (false)
874 << " obj addr: " << format("%p", data.data()) << " new addr: 0"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitSection SectionID: " <<
SectionID << " Name: " << Name << " obj addr: "
<< format("%p", data.data()) << " new addr: 0" <<
" DataSize: " << DataSize << " StubBufSize: " <<
StubBufSize << " Allocate: " << Allocate <<
"\n"; } } while (false)
875 << " DataSize: " << DataSize << " StubBufSize: " << StubBufSizedo { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitSection SectionID: " <<
SectionID << " Name: " << Name << " obj addr: "
<< format("%p", data.data()) << " new addr: 0" <<
" DataSize: " << DataSize << " StubBufSize: " <<
StubBufSize << " Allocate: " << Allocate <<
"\n"; } } while (false)
876 << " Allocate: " << Allocate << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "emitSection SectionID: " <<
SectionID << " Name: " << Name << " obj addr: "
<< format("%p", data.data()) << " new addr: 0" <<
" DataSize: " << DataSize << " StubBufSize: " <<
StubBufSize << " Allocate: " << Allocate <<
"\n"; } } while (false)
;
877 }
878
879 Sections.push_back(
880 SectionEntry(Name, Addr, DataSize, Allocate, (uintptr_t)pData));
881
882 // Debug info sections are linked as if their load address was zero
883 if (!IsRequired)
884 Sections.back().setLoadAddress(0);
885
886 return SectionID;
887}
888
889Expected<unsigned>
890RuntimeDyldImpl::findOrEmitSection(const ObjectFile &Obj,
891 const SectionRef &Section,
892 bool IsCode,
893 ObjSectionToIDMap &LocalSections) {
894
895 unsigned SectionID = 0;
896 ObjSectionToIDMap::iterator i = LocalSections.find(Section);
897 if (i != LocalSections.end())
898 SectionID = i->second;
899 else {
900 if (auto SectionIDOrErr = emitSection(Obj, Section, IsCode))
901 SectionID = *SectionIDOrErr;
902 else
903 return SectionIDOrErr.takeError();
904 LocalSections[Section] = SectionID;
905 }
906 return SectionID;
907}
908
909void RuntimeDyldImpl::addRelocationForSection(const RelocationEntry &RE,
910 unsigned SectionID) {
911 Relocations[SectionID].push_back(RE);
912}
913
914void RuntimeDyldImpl::addRelocationForSymbol(const RelocationEntry &RE,
915 StringRef SymbolName) {
916 // Relocation by symbol. If the symbol is found in the global symbol table,
917 // create an appropriate section relocation. Otherwise, add it to
918 // ExternalSymbolRelocations.
919 RTDyldSymbolTable::const_iterator Loc = GlobalSymbolTable.find(SymbolName);
920 if (Loc == GlobalSymbolTable.end()) {
921 ExternalSymbolRelocations[SymbolName].push_back(RE);
922 } else {
923 // Copy the RE since we want to modify its addend.
924 RelocationEntry RECopy = RE;
925 const auto &SymInfo = Loc->second;
926 RECopy.Addend += SymInfo.getOffset();
927 Relocations[SymInfo.getSectionID()].push_back(RECopy);
928 }
929}
930
931uint8_t *RuntimeDyldImpl::createStubFunction(uint8_t *Addr,
932 unsigned AbiVariant) {
933 if (Arch == Triple::aarch64 || Arch == Triple::aarch64_be ||
934 Arch == Triple::aarch64_32) {
935 // This stub has to be able to access the full address space,
936 // since symbol lookup won't necessarily find a handy, in-range,
937 // PLT stub for functions which could be anywhere.
938 // Stub can use ip0 (== x16) to calculate address
939 writeBytesUnaligned(0xd2e00010, Addr, 4); // movz ip0, #:abs_g3:<addr>
940 writeBytesUnaligned(0xf2c00010, Addr+4, 4); // movk ip0, #:abs_g2_nc:<addr>
941 writeBytesUnaligned(0xf2a00010, Addr+8, 4); // movk ip0, #:abs_g1_nc:<addr>
942 writeBytesUnaligned(0xf2800010, Addr+12, 4); // movk ip0, #:abs_g0_nc:<addr>
943 writeBytesUnaligned(0xd61f0200, Addr+16, 4); // br ip0
944
945 return Addr;
946 } else if (Arch == Triple::arm || Arch == Triple::armeb) {
947 // TODO: There is only ARM far stub now. We should add the Thumb stub,
948 // and stubs for branches Thumb - ARM and ARM - Thumb.
949 writeBytesUnaligned(0xe51ff004, Addr, 4); // ldr pc, [pc, #-4]
950 return Addr + 4;
951 } else if (IsMipsO32ABI || IsMipsN32ABI) {
952 // 0: 3c190000 lui t9,%hi(addr).
953 // 4: 27390000 addiu t9,t9,%lo(addr).
954 // 8: 03200008 jr t9.
955 // c: 00000000 nop.
956 const unsigned LuiT9Instr = 0x3c190000, AdduiT9Instr = 0x27390000;
957 const unsigned NopInstr = 0x0;
958 unsigned JrT9Instr = 0x03200008;
959 if ((AbiVariant & ELF::EF_MIPS_ARCH) == ELF::EF_MIPS_ARCH_32R6 ||
960 (AbiVariant & ELF::EF_MIPS_ARCH) == ELF::EF_MIPS_ARCH_64R6)
961 JrT9Instr = 0x03200009;
962
963 writeBytesUnaligned(LuiT9Instr, Addr, 4);
964 writeBytesUnaligned(AdduiT9Instr, Addr + 4, 4);
965 writeBytesUnaligned(JrT9Instr, Addr + 8, 4);
966 writeBytesUnaligned(NopInstr, Addr + 12, 4);
967 return Addr;
968 } else if (IsMipsN64ABI) {
969 // 0: 3c190000 lui t9,%highest(addr).
970 // 4: 67390000 daddiu t9,t9,%higher(addr).
971 // 8: 0019CC38 dsll t9,t9,16.
972 // c: 67390000 daddiu t9,t9,%hi(addr).
973 // 10: 0019CC38 dsll t9,t9,16.
974 // 14: 67390000 daddiu t9,t9,%lo(addr).
975 // 18: 03200008 jr t9.
976 // 1c: 00000000 nop.
977 const unsigned LuiT9Instr = 0x3c190000, DaddiuT9Instr = 0x67390000,
978 DsllT9Instr = 0x19CC38;
979 const unsigned NopInstr = 0x0;
980 unsigned JrT9Instr = 0x03200008;
981 if ((AbiVariant & ELF::EF_MIPS_ARCH) == ELF::EF_MIPS_ARCH_64R6)
982 JrT9Instr = 0x03200009;
983
984 writeBytesUnaligned(LuiT9Instr, Addr, 4);
985 writeBytesUnaligned(DaddiuT9Instr, Addr + 4, 4);
986 writeBytesUnaligned(DsllT9Instr, Addr + 8, 4);
987 writeBytesUnaligned(DaddiuT9Instr, Addr + 12, 4);
988 writeBytesUnaligned(DsllT9Instr, Addr + 16, 4);
989 writeBytesUnaligned(DaddiuT9Instr, Addr + 20, 4);
990 writeBytesUnaligned(JrT9Instr, Addr + 24, 4);
991 writeBytesUnaligned(NopInstr, Addr + 28, 4);
992 return Addr;
993 } else if (Arch == Triple::ppc64 || Arch == Triple::ppc64le) {
994 // Depending on which version of the ELF ABI is in use, we need to
995 // generate one of two variants of the stub. They both start with
996 // the same sequence to load the target address into r12.
997 writeInt32BE(Addr, 0x3D800000); // lis r12, highest(addr)
998 writeInt32BE(Addr+4, 0x618C0000); // ori r12, higher(addr)
999 writeInt32BE(Addr+8, 0x798C07C6); // sldi r12, r12, 32
1000 writeInt32BE(Addr+12, 0x658C0000); // oris r12, r12, h(addr)
1001 writeInt32BE(Addr+16, 0x618C0000); // ori r12, r12, l(addr)
1002 if (AbiVariant == 2) {
1003 // PowerPC64 stub ELFv2 ABI: The address points to the function itself.
1004 // The address is already in r12 as required by the ABI. Branch to it.
1005 writeInt32BE(Addr+20, 0xF8410018); // std r2, 24(r1)
1006 writeInt32BE(Addr+24, 0x7D8903A6); // mtctr r12
1007 writeInt32BE(Addr+28, 0x4E800420); // bctr
1008 } else {
1009 // PowerPC64 stub ELFv1 ABI: The address points to a function descriptor.
1010 // Load the function address on r11 and sets it to control register. Also
1011 // loads the function TOC in r2 and environment pointer to r11.
1012 writeInt32BE(Addr+20, 0xF8410028); // std r2, 40(r1)
1013 writeInt32BE(Addr+24, 0xE96C0000); // ld r11, 0(r12)
1014 writeInt32BE(Addr+28, 0xE84C0008); // ld r2, 0(r12)
1015 writeInt32BE(Addr+32, 0x7D6903A6); // mtctr r11
1016 writeInt32BE(Addr+36, 0xE96C0010); // ld r11, 16(r2)
1017 writeInt32BE(Addr+40, 0x4E800420); // bctr
1018 }
1019 return Addr;
1020 } else if (Arch == Triple::systemz) {
1021 writeInt16BE(Addr, 0xC418); // lgrl %r1,.+8
1022 writeInt16BE(Addr+2, 0x0000);
1023 writeInt16BE(Addr+4, 0x0004);
1024 writeInt16BE(Addr+6, 0x07F1); // brc 15,%r1
1025 // 8-byte address stored at Addr + 8
1026 return Addr;
1027 } else if (Arch == Triple::x86_64) {
1028 *Addr = 0xFF; // jmp
1029 *(Addr+1) = 0x25; // rip
1030 // 32-bit PC-relative address of the GOT entry will be stored at Addr+2
1031 } else if (Arch == Triple::x86) {
1032 *Addr = 0xE9; // 32-bit pc-relative jump.
1033 }
1034 return Addr;
1035}
1036
1037// Assign an address to a symbol name and resolve all the relocations
1038// associated with it.
1039void RuntimeDyldImpl::reassignSectionAddress(unsigned SectionID,
1040 uint64_t Addr) {
1041 // The address to use for relocation resolution is not
1042 // the address of the local section buffer. We must be doing
1043 // a remote execution environment of some sort. Relocations can't
1044 // be applied until all the sections have been moved. The client must
1045 // trigger this with a call to MCJIT::finalize() or
1046 // RuntimeDyld::resolveRelocations().
1047 //
1048 // Addr is a uint64_t because we can't assume the pointer width
1049 // of the target is the same as that of the host. Just use a generic
1050 // "big enough" type.
1051 LLVM_DEBUG(do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Reassigning address for section "
<< SectionID << " (" << Sections[SectionID
].getName() << "): " << format("0x%016" "l" "x", Sections
[SectionID].getLoadAddress()) << " -> " << format
("0x%016" "l" "x", Addr) << "\n"; } } while (false)
1052 dbgs() << "Reassigning address for section " << SectionID << " ("do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Reassigning address for section "
<< SectionID << " (" << Sections[SectionID
].getName() << "): " << format("0x%016" "l" "x", Sections
[SectionID].getLoadAddress()) << " -> " << format
("0x%016" "l" "x", Addr) << "\n"; } } while (false)
1053 << Sections[SectionID].getName() << "): "do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Reassigning address for section "
<< SectionID << " (" << Sections[SectionID
].getName() << "): " << format("0x%016" "l" "x", Sections
[SectionID].getLoadAddress()) << " -> " << format
("0x%016" "l" "x", Addr) << "\n"; } } while (false)
1054 << format("0x%016" PRIx64, Sections[SectionID].getLoadAddress())do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Reassigning address for section "
<< SectionID << " (" << Sections[SectionID
].getName() << "): " << format("0x%016" "l" "x", Sections
[SectionID].getLoadAddress()) << " -> " << format
("0x%016" "l" "x", Addr) << "\n"; } } while (false)
1055 << " -> " << format("0x%016" PRIx64, Addr) << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Reassigning address for section "
<< SectionID << " (" << Sections[SectionID
].getName() << "): " << format("0x%016" "l" "x", Sections
[SectionID].getLoadAddress()) << " -> " << format
("0x%016" "l" "x", Addr) << "\n"; } } while (false)
;
1056 Sections[SectionID].setLoadAddress(Addr);
1057}
1058
1059void RuntimeDyldImpl::resolveRelocationList(const RelocationList &Relocs,
1060 uint64_t Value) {
1061 for (unsigned i = 0, e = Relocs.size(); i != e; ++i) {
1062 const RelocationEntry &RE = Relocs[i];
1063 // Ignore relocations for sections that were not loaded
1064 if (Sections[RE.SectionID].getAddress() == nullptr)
1065 continue;
1066 resolveRelocation(RE, Value);
1067 }
1068}
1069
1070void RuntimeDyldImpl::applyExternalSymbolRelocations(
1071 const StringMap<JITEvaluatedSymbol> ExternalSymbolMap) {
1072 while (!ExternalSymbolRelocations.empty()) {
1073
1074 StringMap<RelocationList>::iterator i = ExternalSymbolRelocations.begin();
1075
1076 StringRef Name = i->first();
1077 if (Name.size() == 0) {
1078 // This is an absolute symbol, use an address of zero.
1079 LLVM_DEBUG(dbgs() << "Resolving absolute relocations."do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Resolving absolute relocations."
<< "\n"; } } while (false)
1080 << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Resolving absolute relocations."
<< "\n"; } } while (false)
;
1081 RelocationList &Relocs = i->second;
1082 resolveRelocationList(Relocs, 0);
1083 } else {
1084 uint64_t Addr = 0;
1085 JITSymbolFlags Flags;
1086 RTDyldSymbolTable::const_iterator Loc = GlobalSymbolTable.find(Name);
1087 if (Loc == GlobalSymbolTable.end()) {
1088 auto RRI = ExternalSymbolMap.find(Name);
1089 assert(RRI != ExternalSymbolMap.end() && "No result for symbol")((RRI != ExternalSymbolMap.end() && "No result for symbol"
) ? static_cast<void> (0) : __assert_fail ("RRI != ExternalSymbolMap.end() && \"No result for symbol\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 1089, __PRETTY_FUNCTION__))
;
1090 Addr = RRI->second.getAddress();
1091 Flags = RRI->second.getFlags();
1092 // The call to getSymbolAddress may have caused additional modules to
1093 // be loaded, which may have added new entries to the
1094 // ExternalSymbolRelocations map. Consquently, we need to update our
1095 // iterator. This is also why retrieval of the relocation list
1096 // associated with this symbol is deferred until below this point.
1097 // New entries may have been added to the relocation list.
1098 i = ExternalSymbolRelocations.find(Name);
1099 } else {
1100 // We found the symbol in our global table. It was probably in a
1101 // Module that we loaded previously.
1102 const auto &SymInfo = Loc->second;
1103 Addr = getSectionLoadAddress(SymInfo.getSectionID()) +
1104 SymInfo.getOffset();
1105 Flags = SymInfo.getFlags();
1106 }
1107
1108 // FIXME: Implement error handling that doesn't kill the host program!
1109 if (!Addr)
1110 report_fatal_error("Program used external function '" + Name +
1111 "' which could not be resolved!");
1112
1113 // If Resolver returned UINT64_MAX, the client wants to handle this symbol
1114 // manually and we shouldn't resolve its relocations.
1115 if (Addr != UINT64_MAX(18446744073709551615UL)) {
1116
1117 // Tweak the address based on the symbol flags if necessary.
1118 // For example, this is used by RuntimeDyldMachOARM to toggle the low bit
1119 // if the target symbol is Thumb.
1120 Addr = modifyAddressBasedOnFlags(Addr, Flags);
1121
1122 LLVM_DEBUG(dbgs() << "Resolving relocations Name: " << Name << "\t"do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Resolving relocations Name: " <<
Name << "\t" << format("0x%lx", Addr) << "\n"
; } } while (false)
1123 << format("0x%lx", Addr) << "\n")do { if (::llvm::DebugFlag && ::llvm::isCurrentDebugType
("dyld")) { dbgs() << "Resolving relocations Name: " <<
Name << "\t" << format("0x%lx", Addr) << "\n"
; } } while (false)
;
1124 // This list may have been updated when we called getSymbolAddress, so
1125 // don't change this code to get the list earlier.
1126 RelocationList &Relocs = i->second;
1127 resolveRelocationList(Relocs, Addr);
1128 }
1129 }
1130
1131 ExternalSymbolRelocations.erase(i);
1132 }
1133}
1134
1135Error RuntimeDyldImpl::resolveExternalSymbols() {
1136 StringMap<JITEvaluatedSymbol> ExternalSymbolMap;
1137
1138 // Resolution can trigger emission of more symbols, so iterate until
1139 // we've resolved *everything*.
1140 {
1141 JITSymbolResolver::LookupSet ResolvedSymbols;
1142
1143 while (true) {
1144 JITSymbolResolver::LookupSet NewSymbols;
1145
1146 for (auto &RelocKV : ExternalSymbolRelocations) {
1147 StringRef Name = RelocKV.first();
1148 if (!Name.empty() && !GlobalSymbolTable.count(Name) &&
1149 !ResolvedSymbols.count(Name))
1150 NewSymbols.insert(Name);
1151 }
1152
1153 if (NewSymbols.empty())
1154 break;
1155
1156#ifdef _MSC_VER
1157 using ExpectedLookupResult =
1158 MSVCPExpected<JITSymbolResolver::LookupResult>;
1159#else
1160 using ExpectedLookupResult = Expected<JITSymbolResolver::LookupResult>;
1161#endif
1162
1163 auto NewSymbolsP = std::make_shared<std::promise<ExpectedLookupResult>>();
1164 auto NewSymbolsF = NewSymbolsP->get_future();
1165 Resolver.lookup(NewSymbols,
1166 [=](Expected<JITSymbolResolver::LookupResult> Result) {
1167 NewSymbolsP->set_value(std::move(Result));
1168 });
1169
1170 auto NewResolverResults = NewSymbolsF.get();
1171
1172 if (!NewResolverResults)
1173 return NewResolverResults.takeError();
1174
1175 assert(NewResolverResults->size() == NewSymbols.size() &&((NewResolverResults->size() == NewSymbols.size() &&
"Should have errored on unresolved symbols") ? static_cast<
void> (0) : __assert_fail ("NewResolverResults->size() == NewSymbols.size() && \"Should have errored on unresolved symbols\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 1176, __PRETTY_FUNCTION__))
1176 "Should have errored on unresolved symbols")((NewResolverResults->size() == NewSymbols.size() &&
"Should have errored on unresolved symbols") ? static_cast<
void> (0) : __assert_fail ("NewResolverResults->size() == NewSymbols.size() && \"Should have errored on unresolved symbols\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 1176, __PRETTY_FUNCTION__))
;
1177
1178 for (auto &RRKV : *NewResolverResults) {
1179 assert(!ResolvedSymbols.count(RRKV.first) && "Redundant resolution?")((!ResolvedSymbols.count(RRKV.first) && "Redundant resolution?"
) ? static_cast<void> (0) : __assert_fail ("!ResolvedSymbols.count(RRKV.first) && \"Redundant resolution?\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 1179, __PRETTY_FUNCTION__))
;
1180 ExternalSymbolMap.insert(RRKV);
1181 ResolvedSymbols.insert(RRKV.first);
1182 }
1183 }
1184 }
1185
1186 applyExternalSymbolRelocations(ExternalSymbolMap);
1187
1188 return Error::success();
1189}
1190
1191void RuntimeDyldImpl::finalizeAsync(
1192 std::unique_ptr<RuntimeDyldImpl> This,
1193 unique_function<void(Error)> OnEmitted,
1194 std::unique_ptr<MemoryBuffer> UnderlyingBuffer) {
1195
1196 auto SharedThis = std::shared_ptr<RuntimeDyldImpl>(std::move(This));
1197 auto PostResolveContinuation =
1198 [SharedThis, OnEmitted = std::move(OnEmitted),
6
Calling implicit move constructor
7
Calling move constructor for 'unique_function<void (llvm::Error)>'
10
Returning from move constructor for 'unique_function<void (llvm::Error)>'
11
Returning from move constructor
1199 UnderlyingBuffer = std::move(UnderlyingBuffer)](
1200 Expected<JITSymbolResolver::LookupResult> Result) mutable {
1201 if (!Result) {
15
Taking true branch
1202 OnEmitted(Result.takeError());
16
Calling 'unique_function::operator()'
1203 return;
1204 }
1205
1206 /// Copy the result into a StringMap, where the keys are held by value.
1207 StringMap<JITEvaluatedSymbol> Resolved;
1208 for (auto &KV : *Result)
1209 Resolved[KV.first] = KV.second;
1210
1211 SharedThis->applyExternalSymbolRelocations(Resolved);
1212 SharedThis->resolveLocalRelocations();
1213 SharedThis->registerEHFrames();
1214 std::string ErrMsg;
1215 if (SharedThis->MemMgr.finalizeMemory(&ErrMsg))
1216 OnEmitted(make_error<StringError>(std::move(ErrMsg),
1217 inconvertibleErrorCode()));
1218 else
1219 OnEmitted(Error::success());
1220 };
1221
1222 JITSymbolResolver::LookupSet Symbols;
1223
1224 for (auto &RelocKV : SharedThis->ExternalSymbolRelocations) {
1225 StringRef Name = RelocKV.first();
1226 assert(!Name.empty() && "Symbol has no name?")((!Name.empty() && "Symbol has no name?") ? static_cast
<void> (0) : __assert_fail ("!Name.empty() && \"Symbol has no name?\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 1226, __PRETTY_FUNCTION__))
;
1227 assert(!SharedThis->GlobalSymbolTable.count(Name) &&((!SharedThis->GlobalSymbolTable.count(Name) && "Name already processed. RuntimeDyld instances can not be re-used "
"when finalizing with finalizeAsync.") ? static_cast<void
> (0) : __assert_fail ("!SharedThis->GlobalSymbolTable.count(Name) && \"Name already processed. RuntimeDyld instances can not be re-used \" \"when finalizing with finalizeAsync.\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 1229, __PRETTY_FUNCTION__))
1228 "Name already processed. RuntimeDyld instances can not be re-used "((!SharedThis->GlobalSymbolTable.count(Name) && "Name already processed. RuntimeDyld instances can not be re-used "
"when finalizing with finalizeAsync.") ? static_cast<void
> (0) : __assert_fail ("!SharedThis->GlobalSymbolTable.count(Name) && \"Name already processed. RuntimeDyld instances can not be re-used \" \"when finalizing with finalizeAsync.\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 1229, __PRETTY_FUNCTION__))
1229 "when finalizing with finalizeAsync.")((!SharedThis->GlobalSymbolTable.count(Name) && "Name already processed. RuntimeDyld instances can not be re-used "
"when finalizing with finalizeAsync.") ? static_cast<void
> (0) : __assert_fail ("!SharedThis->GlobalSymbolTable.count(Name) && \"Name already processed. RuntimeDyld instances can not be re-used \" \"when finalizing with finalizeAsync.\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 1229, __PRETTY_FUNCTION__))
;
1230 Symbols.insert(Name);
1231 }
1232
1233 if (!Symbols.empty()) {
12
Assuming the condition is false
13
Taking false branch
1234 SharedThis->Resolver.lookup(Symbols, std::move(PostResolveContinuation));
1235 } else
1236 PostResolveContinuation(std::map<StringRef, JITEvaluatedSymbol>());
14
Calling 'operator()'
1237}
1238
1239//===----------------------------------------------------------------------===//
1240// RuntimeDyld class implementation
1241
1242uint64_t RuntimeDyld::LoadedObjectInfo::getSectionLoadAddress(
1243 const object::SectionRef &Sec) const {
1244
1245 auto I = ObjSecToIDMap.find(Sec);
1246 if (I != ObjSecToIDMap.end())
1247 return RTDyld.Sections[I->second].getLoadAddress();
1248
1249 return 0;
1250}
1251
1252void RuntimeDyld::MemoryManager::anchor() {}
1253void JITSymbolResolver::anchor() {}
1254void LegacyJITSymbolResolver::anchor() {}
1255
1256RuntimeDyld::RuntimeDyld(RuntimeDyld::MemoryManager &MemMgr,
1257 JITSymbolResolver &Resolver)
1258 : MemMgr(MemMgr), Resolver(Resolver) {
1259 // FIXME: There's a potential issue lurking here if a single instance of
1260 // RuntimeDyld is used to load multiple objects. The current implementation
1261 // associates a single memory manager with a RuntimeDyld instance. Even
1262 // though the public class spawns a new 'impl' instance for each load,
1263 // they share a single memory manager. This can become a problem when page
1264 // permissions are applied.
1265 Dyld = nullptr;
1266 ProcessAllSections = false;
1267}
1268
1269RuntimeDyld::~RuntimeDyld() {}
1270
1271static std::unique_ptr<RuntimeDyldCOFF>
1272createRuntimeDyldCOFF(
1273 Triple::ArchType Arch, RuntimeDyld::MemoryManager &MM,
1274 JITSymbolResolver &Resolver, bool ProcessAllSections,
1275 RuntimeDyld::NotifyStubEmittedFunction NotifyStubEmitted) {
1276 std::unique_ptr<RuntimeDyldCOFF> Dyld =
1277 RuntimeDyldCOFF::create(Arch, MM, Resolver);
1278 Dyld->setProcessAllSections(ProcessAllSections);
1279 Dyld->setNotifyStubEmitted(std::move(NotifyStubEmitted));
1280 return Dyld;
1281}
1282
1283static std::unique_ptr<RuntimeDyldELF>
1284createRuntimeDyldELF(Triple::ArchType Arch, RuntimeDyld::MemoryManager &MM,
1285 JITSymbolResolver &Resolver, bool ProcessAllSections,
1286 RuntimeDyld::NotifyStubEmittedFunction NotifyStubEmitted) {
1287 std::unique_ptr<RuntimeDyldELF> Dyld =
1288 RuntimeDyldELF::create(Arch, MM, Resolver);
1289 Dyld->setProcessAllSections(ProcessAllSections);
1290 Dyld->setNotifyStubEmitted(std::move(NotifyStubEmitted));
1291 return Dyld;
1292}
1293
1294static std::unique_ptr<RuntimeDyldMachO>
1295createRuntimeDyldMachO(
1296 Triple::ArchType Arch, RuntimeDyld::MemoryManager &MM,
1297 JITSymbolResolver &Resolver,
1298 bool ProcessAllSections,
1299 RuntimeDyld::NotifyStubEmittedFunction NotifyStubEmitted) {
1300 std::unique_ptr<RuntimeDyldMachO> Dyld =
1301 RuntimeDyldMachO::create(Arch, MM, Resolver);
1302 Dyld->setProcessAllSections(ProcessAllSections);
1303 Dyld->setNotifyStubEmitted(std::move(NotifyStubEmitted));
1304 return Dyld;
1305}
1306
1307std::unique_ptr<RuntimeDyld::LoadedObjectInfo>
1308RuntimeDyld::loadObject(const ObjectFile &Obj) {
1309 if (!Dyld) {
1310 if (Obj.isELF())
1311 Dyld =
1312 createRuntimeDyldELF(static_cast<Triple::ArchType>(Obj.getArch()),
1313 MemMgr, Resolver, ProcessAllSections,
1314 std::move(NotifyStubEmitted));
1315 else if (Obj.isMachO())
1316 Dyld = createRuntimeDyldMachO(
1317 static_cast<Triple::ArchType>(Obj.getArch()), MemMgr, Resolver,
1318 ProcessAllSections, std::move(NotifyStubEmitted));
1319 else if (Obj.isCOFF())
1320 Dyld = createRuntimeDyldCOFF(
1321 static_cast<Triple::ArchType>(Obj.getArch()), MemMgr, Resolver,
1322 ProcessAllSections, std::move(NotifyStubEmitted));
1323 else
1324 report_fatal_error("Incompatible object format!");
1325 }
1326
1327 if (!Dyld->isCompatibleFile(Obj))
1328 report_fatal_error("Incompatible object format!");
1329
1330 auto LoadedObjInfo = Dyld->loadObject(Obj);
1331 MemMgr.notifyObjectLoaded(*this, Obj);
1332 return LoadedObjInfo;
1333}
1334
1335void *RuntimeDyld::getSymbolLocalAddress(StringRef Name) const {
1336 if (!Dyld)
1337 return nullptr;
1338 return Dyld->getSymbolLocalAddress(Name);
1339}
1340
1341unsigned RuntimeDyld::getSymbolSectionID(StringRef Name) const {
1342 assert(Dyld && "No RuntimeDyld instance attached")((Dyld && "No RuntimeDyld instance attached") ? static_cast
<void> (0) : __assert_fail ("Dyld && \"No RuntimeDyld instance attached\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 1342, __PRETTY_FUNCTION__))
;
1343 return Dyld->getSymbolSectionID(Name);
1344}
1345
1346JITEvaluatedSymbol RuntimeDyld::getSymbol(StringRef Name) const {
1347 if (!Dyld)
1348 return nullptr;
1349 return Dyld->getSymbol(Name);
1350}
1351
1352std::map<StringRef, JITEvaluatedSymbol> RuntimeDyld::getSymbolTable() const {
1353 if (!Dyld)
1354 return std::map<StringRef, JITEvaluatedSymbol>();
1355 return Dyld->getSymbolTable();
1356}
1357
1358void RuntimeDyld::resolveRelocations() { Dyld->resolveRelocations(); }
1359
1360void RuntimeDyld::reassignSectionAddress(unsigned SectionID, uint64_t Addr) {
1361 Dyld->reassignSectionAddress(SectionID, Addr);
1362}
1363
1364void RuntimeDyld::mapSectionAddress(const void *LocalAddress,
1365 uint64_t TargetAddress) {
1366 Dyld->mapSectionAddress(LocalAddress, TargetAddress);
1367}
1368
1369bool RuntimeDyld::hasError() { return Dyld->hasError(); }
1370
1371StringRef RuntimeDyld::getErrorString() { return Dyld->getErrorString(); }
1372
1373void RuntimeDyld::finalizeWithMemoryManagerLocking() {
1374 bool MemoryFinalizationLocked = MemMgr.FinalizationLocked;
1375 MemMgr.FinalizationLocked = true;
1376 resolveRelocations();
1377 registerEHFrames();
1378 if (!MemoryFinalizationLocked) {
1379 MemMgr.finalizeMemory();
1380 MemMgr.FinalizationLocked = false;
1381 }
1382}
1383
1384StringRef RuntimeDyld::getSectionContent(unsigned SectionID) const {
1385 assert(Dyld && "No Dyld instance attached")((Dyld && "No Dyld instance attached") ? static_cast<
void> (0) : __assert_fail ("Dyld && \"No Dyld instance attached\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 1385, __PRETTY_FUNCTION__))
;
1386 return Dyld->getSectionContent(SectionID);
1387}
1388
1389uint64_t RuntimeDyld::getSectionLoadAddress(unsigned SectionID) const {
1390 assert(Dyld && "No Dyld instance attached")((Dyld && "No Dyld instance attached") ? static_cast<
void> (0) : __assert_fail ("Dyld && \"No Dyld instance attached\""
, "/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/lib/ExecutionEngine/RuntimeDyld/RuntimeDyld.cpp"
, 1390, __PRETTY_FUNCTION__))
;
1391 return Dyld->getSectionLoadAddress(SectionID);
1392}
1393
1394void RuntimeDyld::registerEHFrames() {
1395 if (Dyld)
1396 Dyld->registerEHFrames();
1397}
1398
1399void RuntimeDyld::deregisterEHFrames() {
1400 if (Dyld)
1401 Dyld->deregisterEHFrames();
1402}
1403// FIXME: Kill this with fire once we have a new JIT linker: this is only here
1404// so that we can re-use RuntimeDyld's implementation without twisting the
1405// interface any further for ORC's purposes.
1406void jitLinkForORC(object::ObjectFile &Obj,
1407 std::unique_ptr<MemoryBuffer> UnderlyingBuffer,
1408 RuntimeDyld::MemoryManager &MemMgr,
1409 JITSymbolResolver &Resolver, bool ProcessAllSections,
1410 unique_function<Error(
1411 std::unique_ptr<RuntimeDyld::LoadedObjectInfo> LoadedObj,
1412 std::map<StringRef, JITEvaluatedSymbol>)>
1413 OnLoaded,
1414 unique_function<void(Error)> OnEmitted) {
1415
1416 RuntimeDyld RTDyld(MemMgr, Resolver);
1417 RTDyld.setProcessAllSections(ProcessAllSections);
1418
1419 auto Info = RTDyld.loadObject(Obj);
1420
1421 if (RTDyld.hasError()) {
1
Assuming the condition is false
2
Taking false branch
1422 OnEmitted(make_error<StringError>(RTDyld.getErrorString(),
1423 inconvertibleErrorCode()));
1424 return;
1425 }
1426
1427 if (auto Err = OnLoaded(std::move(Info), RTDyld.getSymbolTable()))
3
Assuming the condition is false
4
Taking false branch
1428 OnEmitted(std::move(Err));
1429
1430 RuntimeDyldImpl::finalizeAsync(std::move(RTDyld.Dyld), std::move(OnEmitted),
5
Calling 'RuntimeDyldImpl::finalizeAsync'
1431 std::move(UnderlyingBuffer));
1432}
1433
1434} // end namespace llvm

/build/llvm-toolchain-snapshot-10~+201911111502510600c19528f1809/llvm/include/llvm/ADT/FunctionExtras.h

1//===- FunctionExtras.h - Function type erasure utilities -------*- 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/// \file
9/// This file provides a collection of function (or more generally, callable)
10/// type erasure utilities supplementing those provided by the standard library
11/// in `<function>`.
12///
13/// It provides `unique_function`, which works like `std::function` but supports
14/// move-only callable objects.
15///
16/// Future plans:
17/// - Add a `function` that provides const, volatile, and ref-qualified support,
18/// which doesn't work with `std::function`.
19/// - Provide support for specifying multiple signatures to type erase callable
20/// objects with an overload set, such as those produced by generic lambdas.
21/// - Expand to include a copyable utility that directly replaces std::function
22/// but brings the above improvements.
23///
24/// Note that LLVM's utilities are greatly simplified by not supporting
25/// allocators.
26///
27/// If the standard library ever begins to provide comparable facilities we can
28/// consider switching to those.
29///
30//===----------------------------------------------------------------------===//
31
32#ifndef LLVM_ADT_FUNCTION_EXTRAS_H
33#define LLVM_ADT_FUNCTION_EXTRAS_H
34
35#include "llvm/ADT/PointerIntPair.h"
36#include "llvm/ADT/PointerUnion.h"
37#include "llvm/Support/type_traits.h"
38#include <memory>
39
40namespace llvm {
41
42template <typename FunctionT> class unique_function;
43
44template <typename ReturnT, typename... ParamTs>
45class unique_function<ReturnT(ParamTs...)> {
46 static constexpr size_t InlineStorageSize = sizeof(void *) * 3;
47
48 // MSVC has a bug and ICEs if we give it a particular dependent value
49 // expression as part of the `std::conditional` below. To work around this,
50 // we build that into a template struct's constexpr bool.
51 template <typename T> struct IsSizeLessThanThresholdT {
52 static constexpr bool value = sizeof(T) <= (2 * sizeof(void *));
53 };
54
55 // Provide a type function to map parameters that won't observe extra copies
56 // or moves and which are small enough to likely pass in register to values
57 // and all other types to l-value reference types. We use this to compute the
58 // types used in our erased call utility to minimize copies and moves unless
59 // doing so would force things unnecessarily into memory.
60 //
61 // The heuristic used is related to common ABI register passing conventions.
62 // It doesn't have to be exact though, and in one way it is more strict
63 // because we want to still be able to observe either moves *or* copies.
64 template <typename T>
65 using AdjustedParamT = typename std::conditional<
66 !std::is_reference<T>::value &&
67 llvm::is_trivially_copy_constructible<T>::value &&
68 llvm::is_trivially_move_constructible<T>::value &&
69 IsSizeLessThanThresholdT<T>::value,
70 T, T &>::type;
71
72 // The type of the erased function pointer we use as a callback to dispatch to
73 // the stored callable when it is trivial to move and destroy.
74 using CallPtrT = ReturnT (*)(void *CallableAddr,
75 AdjustedParamT<ParamTs>... Params);
76 using MovePtrT = void (*)(void *LHSCallableAddr, void *RHSCallableAddr);
77 using DestroyPtrT = void (*)(void *CallableAddr);
78
79 /// A struct to hold a single trivial callback with sufficient alignment for
80 /// our bitpacking.
81 struct alignas(8) TrivialCallback {
82 CallPtrT CallPtr;
83 };
84
85 /// A struct we use to aggregate three callbacks when we need full set of
86 /// operations.
87 struct alignas(8) NonTrivialCallbacks {
88 CallPtrT CallPtr;
89 MovePtrT MovePtr;
90 DestroyPtrT DestroyPtr;
91 };
92
93 // Create a pointer union between either a pointer to a static trivial call
94 // pointer in a struct or a pointer to a static struct of the call, move, and
95 // destroy pointers.
96 using CallbackPointerUnionT =
97 PointerUnion<TrivialCallback *, NonTrivialCallbacks *>;
98
99 // The main storage buffer. This will either have a pointer to out-of-line
100 // storage or an inline buffer storing the callable.
101 union StorageUnionT {
102 // For out-of-line storage we keep a pointer to the underlying storage and
103 // the size. This is enough to deallocate the memory.
104 struct OutOfLineStorageT {
105 void *StoragePtr;
106 size_t Size;
107 size_t Alignment;
108 } OutOfLineStorage;
109 static_assert(
110 sizeof(OutOfLineStorageT) <= InlineStorageSize,
111 "Should always use all of the out-of-line storage for inline storage!");
112
113 // For in-line storage, we just provide an aligned character buffer. We
114 // provide three pointers worth of storage here.
115 typename std::aligned_storage<InlineStorageSize, alignof(void *)>::type
116 InlineStorage;
117 } StorageUnion;
118
119 // A compressed pointer to either our dispatching callback or our table of
120 // dispatching callbacks and the flag for whether the callable itself is
121 // stored inline or not.
122 PointerIntPair<CallbackPointerUnionT, 1, bool> CallbackAndInlineFlag;
123
124 bool isInlineStorage() const { return CallbackAndInlineFlag.getInt(); }
125
126 bool isTrivialCallback() const {
127 return CallbackAndInlineFlag.getPointer().template is<TrivialCallback *>();
128 }
129
130 CallPtrT getTrivialCallback() const {
131 return CallbackAndInlineFlag.getPointer().template get<TrivialCallback *>()->CallPtr;
132 }
133
134 NonTrivialCallbacks *getNonTrivialCallbacks() const {
135 return CallbackAndInlineFlag.getPointer()
136 .template get<NonTrivialCallbacks *>();
137 }
138
139 void *getInlineStorage() { return &StorageUnion.InlineStorage; }
140
141 void *getOutOfLineStorage() {
142 return StorageUnion.OutOfLineStorage.StoragePtr;
20
Undefined or garbage value returned to caller
143 }
144 size_t getOutOfLineStorageSize() const {
145 return StorageUnion.OutOfLineStorage.Size;
146 }
147 size_t getOutOfLineStorageAlignment() const {
148 return StorageUnion.OutOfLineStorage.Alignment;
149 }
150
151 void setOutOfLineStorage(void *Ptr, size_t Size, size_t Alignment) {
152 StorageUnion.OutOfLineStorage = {Ptr, Size, Alignment};
153 }
154
155 template <typename CallableT>
156 static ReturnT CallImpl(void *CallableAddr, AdjustedParamT<ParamTs>... Params) {
157 return (*reinterpret_cast<CallableT *>(CallableAddr))(
158 std::forward<ParamTs>(Params)...);
159 }
160
161 template <typename CallableT>
162 static void MoveImpl(void *LHSCallableAddr, void *RHSCallableAddr) noexcept {
163 new (LHSCallableAddr)
164 CallableT(std::move(*reinterpret_cast<CallableT *>(RHSCallableAddr)));
165 }
166
167 template <typename CallableT>
168 static void DestroyImpl(void *CallableAddr) noexcept {
169 reinterpret_cast<CallableT *>(CallableAddr)->~CallableT();
170 }
171
172public:
173 unique_function() = default;
174 unique_function(std::nullptr_t /*null_callable*/) {}
175
176 ~unique_function() {
177 if (!CallbackAndInlineFlag.getPointer())
178 return;
179
180 // Cache this value so we don't re-check it after type-erased operations.
181 bool IsInlineStorage = isInlineStorage();
182
183 if (!isTrivialCallback())
184 getNonTrivialCallbacks()->DestroyPtr(
185 IsInlineStorage ? getInlineStorage() : getOutOfLineStorage());
186
187 if (!IsInlineStorage)
188 deallocate_buffer(getOutOfLineStorage(), getOutOfLineStorageSize(),
189 getOutOfLineStorageAlignment());
190 }
191
192 unique_function(unique_function &&RHS) noexcept {
193 // Copy the callback and inline flag.
194 CallbackAndInlineFlag = RHS.CallbackAndInlineFlag;
195
196 // If the RHS is empty, just copying the above is sufficient.
197 if (!RHS)
8
Taking true branch
198 return;
9
Returning without writing to 'this->StorageUnion.OutOfLineStorage.StoragePtr'
199
200 if (!isInlineStorage()) {
201 // The out-of-line case is easiest to move.
202 StorageUnion.OutOfLineStorage = RHS.StorageUnion.OutOfLineStorage;
203 } else if (isTrivialCallback()) {
204 // Move is trivial, just memcpy the bytes across.
205 memcpy(getInlineStorage(), RHS.getInlineStorage(), InlineStorageSize);
206 } else {
207 // Non-trivial move, so dispatch to a type-erased implementation.
208 getNonTrivialCallbacks()->MovePtr(getInlineStorage(),
209 RHS.getInlineStorage());
210 }
211
212 // Clear the old callback and inline flag to get back to as-if-null.
213 RHS.CallbackAndInlineFlag = {};
214
215#ifndef NDEBUG
216 // In debug builds, we also scribble across the rest of the storage.
217 memset(RHS.getInlineStorage(), 0xAD, InlineStorageSize);
218#endif
219 }
220
221 unique_function &operator=(unique_function &&RHS) noexcept {
222 if (this == &RHS)
223 return *this;
224
225 // Because we don't try to provide any exception safety guarantees we can
226 // implement move assignment very simply by first destroying the current
227 // object and then move-constructing over top of it.
228 this->~unique_function();
229 new (this) unique_function(std::move(RHS));
230 return *this;
231 }
232
233 template <typename CallableT> unique_function(CallableT Callable) {
234 bool IsInlineStorage = true;
235 void *CallableAddr = getInlineStorage();
236 if (sizeof(CallableT) > InlineStorageSize ||
237 alignof(CallableT) > alignof(decltype(StorageUnion.InlineStorage))) {
238 IsInlineStorage = false;
239 // Allocate out-of-line storage. FIXME: Use an explicit alignment
240 // parameter in C++17 mode.
241 auto Size = sizeof(CallableT);
242 auto Alignment = alignof(CallableT);
243 CallableAddr = allocate_buffer(Size, Alignment);
244 setOutOfLineStorage(CallableAddr, Size, Alignment);
245 }
246
247 // Now move into the storage.
248 new (CallableAddr) CallableT(std::move(Callable));
249
250 // See if we can create a trivial callback. We need the callable to be
251 // trivially moved and trivially destroyed so that we don't have to store
252 // type erased callbacks for those operations.
253 //
254 // FIXME: We should use constexpr if here and below to avoid instantiating
255 // the non-trivial static objects when unnecessary. While the linker should
256 // remove them, it is still wasteful.
257 if (llvm::is_trivially_move_constructible<CallableT>::value &&
258 std::is_trivially_destructible<CallableT>::value) {
259 // We need to create a nicely aligned object. We use a static variable
260 // for this because it is a trivial struct.
261 static TrivialCallback Callback = { &CallImpl<CallableT> };
262
263 CallbackAndInlineFlag = {&Callback, IsInlineStorage};
264 return;
265 }
266
267 // Otherwise, we need to point at an object that contains all the different
268 // type erased behaviors needed. Create a static instance of the struct type
269 // here and then use a pointer to that.
270 static NonTrivialCallbacks Callbacks = {
271 &CallImpl<CallableT>, &MoveImpl<CallableT>, &DestroyImpl<CallableT>};
272
273 CallbackAndInlineFlag = {&Callbacks, IsInlineStorage};
274 }
275
276 ReturnT operator()(ParamTs... Params) {
277 void *CallableAddr =
278 isInlineStorage() ? getInlineStorage() : getOutOfLineStorage();
17
Assuming the condition is false
18
'?' condition is false
19
Calling 'unique_function::getOutOfLineStorage'
279
280 return (isTrivialCallback()
281 ? getTrivialCallback()
282 : getNonTrivialCallbacks()->CallPtr)(CallableAddr, Params...);
283 }
284
285 explicit operator bool() const {
286 return (bool)CallbackAndInlineFlag.getPointer();
287 }
288};
289
290} // end namespace llvm
291
292#endif // LLVM_ADT_FUNCTION_H