Bug Summary

File:include/llvm/Support/Error.h
Warning:line 201, column 5
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'

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 IRMover.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 -mrelocation-model pic -pic-level 2 -mthread-model posix -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-8/lib/clang/8.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/lib/Linker -I /build/llvm-toolchain-snapshot-8~svn345461/lib/Linker -I /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/include -I /build/llvm-toolchain-snapshot-8~svn345461/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/include/clang/8.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-8/lib/clang/8.0.0/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++11 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-8~svn345461/build-llvm/lib/Linker -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-10-27-211344-32123-1 -x c++ /build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp -faddrsig

/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp

1//===- lib/Linker/IRMover.cpp ---------------------------------------------===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#include "llvm/Linker/IRMover.h"
11#include "LinkDiagnosticInfo.h"
12#include "llvm/ADT/SetVector.h"
13#include "llvm/ADT/SmallString.h"
14#include "llvm/ADT/Triple.h"
15#include "llvm/IR/Constants.h"
16#include "llvm/IR/DebugInfo.h"
17#include "llvm/IR/DiagnosticPrinter.h"
18#include "llvm/IR/GVMaterializer.h"
19#include "llvm/IR/Intrinsics.h"
20#include "llvm/IR/TypeFinder.h"
21#include "llvm/Support/Error.h"
22#include "llvm/Transforms/Utils/Cloning.h"
23#include <utility>
24using namespace llvm;
25
26//===----------------------------------------------------------------------===//
27// TypeMap implementation.
28//===----------------------------------------------------------------------===//
29
30namespace {
31class TypeMapTy : public ValueMapTypeRemapper {
32 /// This is a mapping from a source type to a destination type to use.
33 DenseMap<Type *, Type *> MappedTypes;
34
35 /// When checking to see if two subgraphs are isomorphic, we speculatively
36 /// add types to MappedTypes, but keep track of them here in case we need to
37 /// roll back.
38 SmallVector<Type *, 16> SpeculativeTypes;
39
40 SmallVector<StructType *, 16> SpeculativeDstOpaqueTypes;
41
42 /// This is a list of non-opaque structs in the source module that are mapped
43 /// to an opaque struct in the destination module.
44 SmallVector<StructType *, 16> SrcDefinitionsToResolve;
45
46 /// This is the set of opaque types in the destination modules who are
47 /// getting a body from the source module.
48 SmallPtrSet<StructType *, 16> DstResolvedOpaqueTypes;
49
50public:
51 TypeMapTy(IRMover::IdentifiedStructTypeSet &DstStructTypesSet)
52 : DstStructTypesSet(DstStructTypesSet) {}
53
54 IRMover::IdentifiedStructTypeSet &DstStructTypesSet;
55 /// Indicate that the specified type in the destination module is conceptually
56 /// equivalent to the specified type in the source module.
57 void addTypeMapping(Type *DstTy, Type *SrcTy);
58
59 /// Produce a body for an opaque type in the dest module from a type
60 /// definition in the source module.
61 void linkDefinedTypeBodies();
62
63 /// Return the mapped type to use for the specified input type from the
64 /// source module.
65 Type *get(Type *SrcTy);
66 Type *get(Type *SrcTy, SmallPtrSet<StructType *, 8> &Visited);
67
68 void finishType(StructType *DTy, StructType *STy, ArrayRef<Type *> ETypes);
69
70 FunctionType *get(FunctionType *T) {
71 return cast<FunctionType>(get((Type *)T));
72 }
73
74private:
75 Type *remapType(Type *SrcTy) override { return get(SrcTy); }
76
77 bool areTypesIsomorphic(Type *DstTy, Type *SrcTy);
78};
79}
80
81void TypeMapTy::addTypeMapping(Type *DstTy, Type *SrcTy) {
82 assert(SpeculativeTypes.empty())((SpeculativeTypes.empty()) ? static_cast<void> (0) : __assert_fail
("SpeculativeTypes.empty()", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 82, __PRETTY_FUNCTION__))
;
83 assert(SpeculativeDstOpaqueTypes.empty())((SpeculativeDstOpaqueTypes.empty()) ? static_cast<void>
(0) : __assert_fail ("SpeculativeDstOpaqueTypes.empty()", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 83, __PRETTY_FUNCTION__))
;
84
85 // Check to see if these types are recursively isomorphic and establish a
86 // mapping between them if so.
87 if (!areTypesIsomorphic(DstTy, SrcTy)) {
88 // Oops, they aren't isomorphic. Just discard this request by rolling out
89 // any speculative mappings we've established.
90 for (Type *Ty : SpeculativeTypes)
91 MappedTypes.erase(Ty);
92
93 SrcDefinitionsToResolve.resize(SrcDefinitionsToResolve.size() -
94 SpeculativeDstOpaqueTypes.size());
95 for (StructType *Ty : SpeculativeDstOpaqueTypes)
96 DstResolvedOpaqueTypes.erase(Ty);
97 } else {
98 // SrcTy and DstTy are recursively ismorphic. We clear names of SrcTy
99 // and all its descendants to lower amount of renaming in LLVM context
100 // Renaming occurs because we load all source modules to the same context
101 // and declaration with existing name gets renamed (i.e Foo -> Foo.42).
102 // As a result we may get several different types in the destination
103 // module, which are in fact the same.
104 for (Type *Ty : SpeculativeTypes)
105 if (auto *STy = dyn_cast<StructType>(Ty))
106 if (STy->hasName())
107 STy->setName("");
108 }
109 SpeculativeTypes.clear();
110 SpeculativeDstOpaqueTypes.clear();
111}
112
113/// Recursively walk this pair of types, returning true if they are isomorphic,
114/// false if they are not.
115bool TypeMapTy::areTypesIsomorphic(Type *DstTy, Type *SrcTy) {
116 // Two types with differing kinds are clearly not isomorphic.
117 if (DstTy->getTypeID() != SrcTy->getTypeID())
118 return false;
119
120 // If we have an entry in the MappedTypes table, then we have our answer.
121 Type *&Entry = MappedTypes[SrcTy];
122 if (Entry)
123 return Entry == DstTy;
124
125 // Two identical types are clearly isomorphic. Remember this
126 // non-speculatively.
127 if (DstTy == SrcTy) {
128 Entry = DstTy;
129 return true;
130 }
131
132 // Okay, we have two types with identical kinds that we haven't seen before.
133
134 // If this is an opaque struct type, special case it.
135 if (StructType *SSTy = dyn_cast<StructType>(SrcTy)) {
136 // Mapping an opaque type to any struct, just keep the dest struct.
137 if (SSTy->isOpaque()) {
138 Entry = DstTy;
139 SpeculativeTypes.push_back(SrcTy);
140 return true;
141 }
142
143 // Mapping a non-opaque source type to an opaque dest. If this is the first
144 // type that we're mapping onto this destination type then we succeed. Keep
145 // the dest, but fill it in later. If this is the second (different) type
146 // that we're trying to map onto the same opaque type then we fail.
147 if (cast<StructType>(DstTy)->isOpaque()) {
148 // We can only map one source type onto the opaque destination type.
149 if (!DstResolvedOpaqueTypes.insert(cast<StructType>(DstTy)).second)
150 return false;
151 SrcDefinitionsToResolve.push_back(SSTy);
152 SpeculativeTypes.push_back(SrcTy);
153 SpeculativeDstOpaqueTypes.push_back(cast<StructType>(DstTy));
154 Entry = DstTy;
155 return true;
156 }
157 }
158
159 // If the number of subtypes disagree between the two types, then we fail.
160 if (SrcTy->getNumContainedTypes() != DstTy->getNumContainedTypes())
161 return false;
162
163 // Fail if any of the extra properties (e.g. array size) of the type disagree.
164 if (isa<IntegerType>(DstTy))
165 return false; // bitwidth disagrees.
166 if (PointerType *PT = dyn_cast<PointerType>(DstTy)) {
167 if (PT->getAddressSpace() != cast<PointerType>(SrcTy)->getAddressSpace())
168 return false;
169 } else if (FunctionType *FT = dyn_cast<FunctionType>(DstTy)) {
170 if (FT->isVarArg() != cast<FunctionType>(SrcTy)->isVarArg())
171 return false;
172 } else if (StructType *DSTy = dyn_cast<StructType>(DstTy)) {
173 StructType *SSTy = cast<StructType>(SrcTy);
174 if (DSTy->isLiteral() != SSTy->isLiteral() ||
175 DSTy->isPacked() != SSTy->isPacked())
176 return false;
177 } else if (auto *DSeqTy = dyn_cast<SequentialType>(DstTy)) {
178 if (DSeqTy->getNumElements() !=
179 cast<SequentialType>(SrcTy)->getNumElements())
180 return false;
181 }
182
183 // Otherwise, we speculate that these two types will line up and recursively
184 // check the subelements.
185 Entry = DstTy;
186 SpeculativeTypes.push_back(SrcTy);
187
188 for (unsigned I = 0, E = SrcTy->getNumContainedTypes(); I != E; ++I)
189 if (!areTypesIsomorphic(DstTy->getContainedType(I),
190 SrcTy->getContainedType(I)))
191 return false;
192
193 // If everything seems to have lined up, then everything is great.
194 return true;
195}
196
197void TypeMapTy::linkDefinedTypeBodies() {
198 SmallVector<Type *, 16> Elements;
199 for (StructType *SrcSTy : SrcDefinitionsToResolve) {
200 StructType *DstSTy = cast<StructType>(MappedTypes[SrcSTy]);
201 assert(DstSTy->isOpaque())((DstSTy->isOpaque()) ? static_cast<void> (0) : __assert_fail
("DstSTy->isOpaque()", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 201, __PRETTY_FUNCTION__))
;
202
203 // Map the body of the source type over to a new body for the dest type.
204 Elements.resize(SrcSTy->getNumElements());
205 for (unsigned I = 0, E = Elements.size(); I != E; ++I)
206 Elements[I] = get(SrcSTy->getElementType(I));
207
208 DstSTy->setBody(Elements, SrcSTy->isPacked());
209 DstStructTypesSet.switchToNonOpaque(DstSTy);
210 }
211 SrcDefinitionsToResolve.clear();
212 DstResolvedOpaqueTypes.clear();
213}
214
215void TypeMapTy::finishType(StructType *DTy, StructType *STy,
216 ArrayRef<Type *> ETypes) {
217 DTy->setBody(ETypes, STy->isPacked());
218
219 // Steal STy's name.
220 if (STy->hasName()) {
221 SmallString<16> TmpName = STy->getName();
222 STy->setName("");
223 DTy->setName(TmpName);
224 }
225
226 DstStructTypesSet.addNonOpaque(DTy);
227}
228
229Type *TypeMapTy::get(Type *Ty) {
230 SmallPtrSet<StructType *, 8> Visited;
231 return get(Ty, Visited);
232}
233
234Type *TypeMapTy::get(Type *Ty, SmallPtrSet<StructType *, 8> &Visited) {
235 // If we already have an entry for this type, return it.
236 Type **Entry = &MappedTypes[Ty];
237 if (*Entry)
238 return *Entry;
239
240 // These are types that LLVM itself will unique.
241 bool IsUniqued = !isa<StructType>(Ty) || cast<StructType>(Ty)->isLiteral();
242
243 if (!IsUniqued) {
244 StructType *STy = cast<StructType>(Ty);
245 // This is actually a type from the destination module, this can be reached
246 // when this type is loaded in another module, added to DstStructTypesSet,
247 // and then we reach the same type in another module where it has not been
248 // added to MappedTypes. (PR37684)
249 if (STy->getContext().isODRUniquingDebugTypes() && !STy->isOpaque() &&
250 DstStructTypesSet.hasType(STy))
251 return *Entry = STy;
252
253#ifndef NDEBUG
254 for (auto &Pair : MappedTypes) {
255 assert(!(Pair.first != Ty && Pair.second == Ty) &&((!(Pair.first != Ty && Pair.second == Ty) &&
"mapping to a source type") ? static_cast<void> (0) : __assert_fail
("!(Pair.first != Ty && Pair.second == Ty) && \"mapping to a source type\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 256, __PRETTY_FUNCTION__))
256 "mapping to a source type")((!(Pair.first != Ty && Pair.second == Ty) &&
"mapping to a source type") ? static_cast<void> (0) : __assert_fail
("!(Pair.first != Ty && Pair.second == Ty) && \"mapping to a source type\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 256, __PRETTY_FUNCTION__))
;
257 }
258#endif
259
260 if (!Visited.insert(STy).second) {
261 StructType *DTy = StructType::create(Ty->getContext());
262 return *Entry = DTy;
263 }
264 }
265
266 // If this is not a recursive type, then just map all of the elements and
267 // then rebuild the type from inside out.
268 SmallVector<Type *, 4> ElementTypes;
269
270 // If there are no element types to map, then the type is itself. This is
271 // true for the anonymous {} struct, things like 'float', integers, etc.
272 if (Ty->getNumContainedTypes() == 0 && IsUniqued)
273 return *Entry = Ty;
274
275 // Remap all of the elements, keeping track of whether any of them change.
276 bool AnyChange = false;
277 ElementTypes.resize(Ty->getNumContainedTypes());
278 for (unsigned I = 0, E = Ty->getNumContainedTypes(); I != E; ++I) {
279 ElementTypes[I] = get(Ty->getContainedType(I), Visited);
280 AnyChange |= ElementTypes[I] != Ty->getContainedType(I);
281 }
282
283 // If we found our type while recursively processing stuff, just use it.
284 Entry = &MappedTypes[Ty];
285 if (*Entry) {
286 if (auto *DTy = dyn_cast<StructType>(*Entry)) {
287 if (DTy->isOpaque()) {
288 auto *STy = cast<StructType>(Ty);
289 finishType(DTy, STy, ElementTypes);
290 }
291 }
292 return *Entry;
293 }
294
295 // If all of the element types mapped directly over and the type is not
296 // a named struct, then the type is usable as-is.
297 if (!AnyChange && IsUniqued)
298 return *Entry = Ty;
299
300 // Otherwise, rebuild a modified type.
301 switch (Ty->getTypeID()) {
302 default:
303 llvm_unreachable("unknown derived type to remap")::llvm::llvm_unreachable_internal("unknown derived type to remap"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 303)
;
304 case Type::ArrayTyID:
305 return *Entry = ArrayType::get(ElementTypes[0],
306 cast<ArrayType>(Ty)->getNumElements());
307 case Type::VectorTyID:
308 return *Entry = VectorType::get(ElementTypes[0],
309 cast<VectorType>(Ty)->getNumElements());
310 case Type::PointerTyID:
311 return *Entry = PointerType::get(ElementTypes[0],
312 cast<PointerType>(Ty)->getAddressSpace());
313 case Type::FunctionTyID:
314 return *Entry = FunctionType::get(ElementTypes[0],
315 makeArrayRef(ElementTypes).slice(1),
316 cast<FunctionType>(Ty)->isVarArg());
317 case Type::StructTyID: {
318 auto *STy = cast<StructType>(Ty);
319 bool IsPacked = STy->isPacked();
320 if (IsUniqued)
321 return *Entry = StructType::get(Ty->getContext(), ElementTypes, IsPacked);
322
323 // If the type is opaque, we can just use it directly.
324 if (STy->isOpaque()) {
325 DstStructTypesSet.addOpaque(STy);
326 return *Entry = Ty;
327 }
328
329 if (StructType *OldT =
330 DstStructTypesSet.findNonOpaque(ElementTypes, IsPacked)) {
331 STy->setName("");
332 return *Entry = OldT;
333 }
334
335 if (!AnyChange) {
336 DstStructTypesSet.addNonOpaque(STy);
337 return *Entry = Ty;
338 }
339
340 StructType *DTy = StructType::create(Ty->getContext());
341 finishType(DTy, STy, ElementTypes);
342 return *Entry = DTy;
343 }
344 }
345}
346
347LinkDiagnosticInfo::LinkDiagnosticInfo(DiagnosticSeverity Severity,
348 const Twine &Msg)
349 : DiagnosticInfo(DK_Linker, Severity), Msg(Msg) {}
350void LinkDiagnosticInfo::print(DiagnosticPrinter &DP) const { DP << Msg; }
351
352//===----------------------------------------------------------------------===//
353// IRLinker implementation.
354//===----------------------------------------------------------------------===//
355
356namespace {
357class IRLinker;
358
359/// Creates prototypes for functions that are lazily linked on the fly. This
360/// speeds up linking for modules with many/ lazily linked functions of which
361/// few get used.
362class GlobalValueMaterializer final : public ValueMaterializer {
363 IRLinker &TheIRLinker;
364
365public:
366 GlobalValueMaterializer(IRLinker &TheIRLinker) : TheIRLinker(TheIRLinker) {}
367 Value *materialize(Value *V) override;
368};
369
370class LocalValueMaterializer final : public ValueMaterializer {
371 IRLinker &TheIRLinker;
372
373public:
374 LocalValueMaterializer(IRLinker &TheIRLinker) : TheIRLinker(TheIRLinker) {}
375 Value *materialize(Value *V) override;
376};
377
378/// Type of the Metadata map in \a ValueToValueMapTy.
379typedef DenseMap<const Metadata *, TrackingMDRef> MDMapT;
380
381/// This is responsible for keeping track of the state used for moving data
382/// from SrcM to DstM.
383class IRLinker {
384 Module &DstM;
385 std::unique_ptr<Module> SrcM;
386
387 /// See IRMover::move().
388 std::function<void(GlobalValue &, IRMover::ValueAdder)> AddLazyFor;
389
390 TypeMapTy TypeMap;
391 GlobalValueMaterializer GValMaterializer;
392 LocalValueMaterializer LValMaterializer;
393
394 /// A metadata map that's shared between IRLinker instances.
395 MDMapT &SharedMDs;
396
397 /// Mapping of values from what they used to be in Src, to what they are now
398 /// in DstM. ValueToValueMapTy is a ValueMap, which involves some overhead
399 /// due to the use of Value handles which the Linker doesn't actually need,
400 /// but this allows us to reuse the ValueMapper code.
401 ValueToValueMapTy ValueMap;
402 ValueToValueMapTy AliasValueMap;
403
404 DenseSet<GlobalValue *> ValuesToLink;
405 std::vector<GlobalValue *> Worklist;
406
407 void maybeAdd(GlobalValue *GV) {
408 if (ValuesToLink.insert(GV).second)
409 Worklist.push_back(GV);
410 }
411
412 /// Whether we are importing globals for ThinLTO, as opposed to linking the
413 /// source module. If this flag is set, it means that we can rely on some
414 /// other object file to define any non-GlobalValue entities defined by the
415 /// source module. This currently causes us to not link retained types in
416 /// debug info metadata and module inline asm.
417 bool IsPerformingImport;
418
419 /// Set to true when all global value body linking is complete (including
420 /// lazy linking). Used to prevent metadata linking from creating new
421 /// references.
422 bool DoneLinkingBodies = false;
423
424 /// The Error encountered during materialization. We use an Optional here to
425 /// avoid needing to manage an unconsumed success value.
426 Optional<Error> FoundError;
427 void setError(Error E) {
428 if (E)
429 FoundError = std::move(E);
430 }
431
432 /// Most of the errors produced by this module are inconvertible StringErrors.
433 /// This convenience function lets us return one of those more easily.
434 Error stringErr(const Twine &T) {
435 return make_error<StringError>(T, inconvertibleErrorCode());
18
Calling 'make_error<llvm::StringError, const llvm::Twine &, std::error_code>'
436 }
437
438 /// Entry point for mapping values and alternate context for mapping aliases.
439 ValueMapper Mapper;
440 unsigned AliasMCID;
441
442 /// Handles cloning of a global values from the source module into
443 /// the destination module, including setting the attributes and visibility.
444 GlobalValue *copyGlobalValueProto(const GlobalValue *SGV, bool ForDefinition);
445
446 void emitWarning(const Twine &Message) {
447 SrcM->getContext().diagnose(LinkDiagnosticInfo(DS_Warning, Message));
448 }
449
450 /// Given a global in the source module, return the global in the
451 /// destination module that is being linked to, if any.
452 GlobalValue *getLinkedToGlobal(const GlobalValue *SrcGV) {
453 // If the source has no name it can't link. If it has local linkage,
454 // there is no name match-up going on.
455 if (!SrcGV->hasName() || SrcGV->hasLocalLinkage())
456 return nullptr;
457
458 // Otherwise see if we have a match in the destination module's symtab.
459 GlobalValue *DGV = DstM.getNamedValue(SrcGV->getName());
460 if (!DGV)
461 return nullptr;
462
463 // If we found a global with the same name in the dest module, but it has
464 // internal linkage, we are really not doing any linkage here.
465 if (DGV->hasLocalLinkage())
466 return nullptr;
467
468 // Otherwise, we do in fact link to the destination global.
469 return DGV;
470 }
471
472 void computeTypeMapping();
473
474 Expected<Constant *> linkAppendingVarProto(GlobalVariable *DstGV,
475 const GlobalVariable *SrcGV);
476
477 /// Given the GlobaValue \p SGV in the source module, and the matching
478 /// GlobalValue \p DGV (if any), return true if the linker will pull \p SGV
479 /// into the destination module.
480 ///
481 /// Note this code may call the client-provided \p AddLazyFor.
482 bool shouldLink(GlobalValue *DGV, GlobalValue &SGV);
483 Expected<Constant *> linkGlobalValueProto(GlobalValue *GV, bool ForAlias);
484
485 Error linkModuleFlagsMetadata();
486
487 void linkGlobalVariable(GlobalVariable &Dst, GlobalVariable &Src);
488 Error linkFunctionBody(Function &Dst, Function &Src);
489 void linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src);
490 Error linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src);
491
492 /// Functions that take care of cloning a specific global value type
493 /// into the destination module.
494 GlobalVariable *copyGlobalVariableProto(const GlobalVariable *SGVar);
495 Function *copyFunctionProto(const Function *SF);
496 GlobalValue *copyGlobalAliasProto(const GlobalAlias *SGA);
497
498 /// When importing for ThinLTO, prevent importing of types listed on
499 /// the DICompileUnit that we don't need a copy of in the importing
500 /// module.
501 void prepareCompileUnitsForImport();
502 void linkNamedMDNodes();
503
504public:
505 IRLinker(Module &DstM, MDMapT &SharedMDs,
506 IRMover::IdentifiedStructTypeSet &Set, std::unique_ptr<Module> SrcM,
507 ArrayRef<GlobalValue *> ValuesToLink,
508 std::function<void(GlobalValue &, IRMover::ValueAdder)> AddLazyFor,
509 bool IsPerformingImport)
510 : DstM(DstM), SrcM(std::move(SrcM)), AddLazyFor(std::move(AddLazyFor)),
511 TypeMap(Set), GValMaterializer(*this), LValMaterializer(*this),
512 SharedMDs(SharedMDs), IsPerformingImport(IsPerformingImport),
513 Mapper(ValueMap, RF_MoveDistinctMDs | RF_IgnoreMissingLocals, &TypeMap,
514 &GValMaterializer),
515 AliasMCID(Mapper.registerAlternateMappingContext(AliasValueMap,
516 &LValMaterializer)) {
517 ValueMap.getMDMap() = std::move(SharedMDs);
518 for (GlobalValue *GV : ValuesToLink)
519 maybeAdd(GV);
520 if (IsPerformingImport)
521 prepareCompileUnitsForImport();
522 }
523 ~IRLinker() { SharedMDs = std::move(*ValueMap.getMDMap()); }
524
525 Error run();
526 Value *materialize(Value *V, bool ForAlias);
527};
528}
529
530/// The LLVM SymbolTable class autorenames globals that conflict in the symbol
531/// table. This is good for all clients except for us. Go through the trouble
532/// to force this back.
533static void forceRenaming(GlobalValue *GV, StringRef Name) {
534 // If the global doesn't force its name or if it already has the right name,
535 // there is nothing for us to do.
536 if (GV->hasLocalLinkage() || GV->getName() == Name)
537 return;
538
539 Module *M = GV->getParent();
540
541 // If there is a conflict, rename the conflict.
542 if (GlobalValue *ConflictGV = M->getNamedValue(Name)) {
543 GV->takeName(ConflictGV);
544 ConflictGV->setName(Name); // This will cause ConflictGV to get renamed
545 assert(ConflictGV->getName() != Name && "forceRenaming didn't work")((ConflictGV->getName() != Name && "forceRenaming didn't work"
) ? static_cast<void> (0) : __assert_fail ("ConflictGV->getName() != Name && \"forceRenaming didn't work\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 545, __PRETTY_FUNCTION__))
;
546 } else {
547 GV->setName(Name); // Force the name back
548 }
549}
550
551Value *GlobalValueMaterializer::materialize(Value *SGV) {
552 return TheIRLinker.materialize(SGV, false);
1
Calling 'IRLinker::materialize'
553}
554
555Value *LocalValueMaterializer::materialize(Value *SGV) {
556 return TheIRLinker.materialize(SGV, true);
557}
558
559Value *IRLinker::materialize(Value *V, bool ForAlias) {
560 auto *SGV = dyn_cast<GlobalValue>(V);
561 if (!SGV)
2
Taking false branch
562 return nullptr;
563
564 Expected<Constant *> NewProto = linkGlobalValueProto(SGV, ForAlias);
3
Calling 'IRLinker::linkGlobalValueProto'
565 if (!NewProto) {
566 setError(NewProto.takeError());
567 return nullptr;
568 }
569 if (!*NewProto)
570 return nullptr;
571
572 GlobalValue *New = dyn_cast<GlobalValue>(*NewProto);
573 if (!New)
574 return *NewProto;
575
576 // If we already created the body, just return.
577 if (auto *F = dyn_cast<Function>(New)) {
578 if (!F->isDeclaration())
579 return New;
580 } else if (auto *V = dyn_cast<GlobalVariable>(New)) {
581 if (V->hasInitializer() || V->hasAppendingLinkage())
582 return New;
583 } else {
584 auto *A = cast<GlobalAlias>(New);
585 if (A->getAliasee())
586 return New;
587 }
588
589 // When linking a global for an alias, it will always be linked. However we
590 // need to check if it was not already scheduled to satisfy a reference from a
591 // regular global value initializer. We know if it has been schedule if the
592 // "New" GlobalValue that is mapped here for the alias is the same as the one
593 // already mapped. If there is an entry in the ValueMap but the value is
594 // different, it means that the value already had a definition in the
595 // destination module (linkonce for instance), but we need a new definition
596 // for the alias ("New" will be different.
597 if (ForAlias && ValueMap.lookup(SGV) == New)
598 return New;
599
600 if (ForAlias || shouldLink(New, *SGV))
601 setError(linkGlobalValueBody(*New, *SGV));
602
603 return New;
604}
605
606/// Loop through the global variables in the src module and merge them into the
607/// dest module.
608GlobalVariable *IRLinker::copyGlobalVariableProto(const GlobalVariable *SGVar) {
609 // No linking to be performed or linking from the source: simply create an
610 // identical version of the symbol over in the dest module... the
611 // initializer will be filled in later by LinkGlobalInits.
612 GlobalVariable *NewDGV =
613 new GlobalVariable(DstM, TypeMap.get(SGVar->getValueType()),
614 SGVar->isConstant(), GlobalValue::ExternalLinkage,
615 /*init*/ nullptr, SGVar->getName(),
616 /*insertbefore*/ nullptr, SGVar->getThreadLocalMode(),
617 SGVar->getType()->getAddressSpace());
618 NewDGV->setAlignment(SGVar->getAlignment());
619 NewDGV->copyAttributesFrom(SGVar);
620 return NewDGV;
621}
622
623/// Link the function in the source module into the destination module if
624/// needed, setting up mapping information.
625Function *IRLinker::copyFunctionProto(const Function *SF) {
626 // If there is no linkage to be performed or we are linking from the source,
627 // bring SF over.
628 auto *F =
629 Function::Create(TypeMap.get(SF->getFunctionType()),
630 GlobalValue::ExternalLinkage, SF->getName(), &DstM);
631 F->copyAttributesFrom(SF);
632 return F;
633}
634
635/// Set up prototypes for any aliases that come over from the source module.
636GlobalValue *IRLinker::copyGlobalAliasProto(const GlobalAlias *SGA) {
637 // If there is no linkage to be performed or we're linking from the source,
638 // bring over SGA.
639 auto *Ty = TypeMap.get(SGA->getValueType());
640 auto *GA =
641 GlobalAlias::create(Ty, SGA->getType()->getPointerAddressSpace(),
642 GlobalValue::ExternalLinkage, SGA->getName(), &DstM);
643 GA->copyAttributesFrom(SGA);
644 return GA;
645}
646
647GlobalValue *IRLinker::copyGlobalValueProto(const GlobalValue *SGV,
648 bool ForDefinition) {
649 GlobalValue *NewGV;
650 if (auto *SGVar = dyn_cast<GlobalVariable>(SGV)) {
651 NewGV = copyGlobalVariableProto(SGVar);
652 } else if (auto *SF = dyn_cast<Function>(SGV)) {
653 NewGV = copyFunctionProto(SF);
654 } else {
655 if (ForDefinition)
656 NewGV = copyGlobalAliasProto(cast<GlobalAlias>(SGV));
657 else if (SGV->getValueType()->isFunctionTy())
658 NewGV =
659 Function::Create(cast<FunctionType>(TypeMap.get(SGV->getValueType())),
660 GlobalValue::ExternalLinkage, SGV->getName(), &DstM);
661 else
662 NewGV = new GlobalVariable(
663 DstM, TypeMap.get(SGV->getValueType()),
664 /*isConstant*/ false, GlobalValue::ExternalLinkage,
665 /*init*/ nullptr, SGV->getName(),
666 /*insertbefore*/ nullptr, SGV->getThreadLocalMode(),
667 SGV->getType()->getAddressSpace());
668 }
669
670 if (ForDefinition)
671 NewGV->setLinkage(SGV->getLinkage());
672 else if (SGV->hasExternalWeakLinkage())
673 NewGV->setLinkage(GlobalValue::ExternalWeakLinkage);
674
675 if (auto *NewGO = dyn_cast<GlobalObject>(NewGV)) {
676 // Metadata for global variables and function declarations is copied eagerly.
677 if (isa<GlobalVariable>(SGV) || SGV->isDeclaration())
678 NewGO->copyMetadata(cast<GlobalObject>(SGV), 0);
679 }
680
681 // Remove these copied constants in case this stays a declaration, since
682 // they point to the source module. If the def is linked the values will
683 // be mapped in during linkFunctionBody.
684 if (auto *NewF = dyn_cast<Function>(NewGV)) {
685 NewF->setPersonalityFn(nullptr);
686 NewF->setPrefixData(nullptr);
687 NewF->setPrologueData(nullptr);
688 }
689
690 return NewGV;
691}
692
693static StringRef getTypeNamePrefix(StringRef Name) {
694 size_t DotPos = Name.rfind('.');
695 return (DotPos == 0 || DotPos == StringRef::npos || Name.back() == '.' ||
696 !isdigit(static_cast<unsigned char>(Name[DotPos + 1])))
697 ? Name
698 : Name.substr(0, DotPos);
699}
700
701/// Loop over all of the linked values to compute type mappings. For example,
702/// if we link "extern Foo *x" and "Foo *x = NULL", then we have two struct
703/// types 'Foo' but one got renamed when the module was loaded into the same
704/// LLVMContext.
705void IRLinker::computeTypeMapping() {
706 for (GlobalValue &SGV : SrcM->globals()) {
707 GlobalValue *DGV = getLinkedToGlobal(&SGV);
708 if (!DGV)
709 continue;
710
711 if (!DGV->hasAppendingLinkage() || !SGV.hasAppendingLinkage()) {
712 TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
713 continue;
714 }
715
716 // Unify the element type of appending arrays.
717 ArrayType *DAT = cast<ArrayType>(DGV->getValueType());
718 ArrayType *SAT = cast<ArrayType>(SGV.getValueType());
719 TypeMap.addTypeMapping(DAT->getElementType(), SAT->getElementType());
720 }
721
722 for (GlobalValue &SGV : *SrcM)
723 if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
724 TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
725
726 for (GlobalValue &SGV : SrcM->aliases())
727 if (GlobalValue *DGV = getLinkedToGlobal(&SGV))
728 TypeMap.addTypeMapping(DGV->getType(), SGV.getType());
729
730 // Incorporate types by name, scanning all the types in the source module.
731 // At this point, the destination module may have a type "%foo = { i32 }" for
732 // example. When the source module got loaded into the same LLVMContext, if
733 // it had the same type, it would have been renamed to "%foo.42 = { i32 }".
734 std::vector<StructType *> Types = SrcM->getIdentifiedStructTypes();
735 for (StructType *ST : Types) {
736 if (!ST->hasName())
737 continue;
738
739 if (TypeMap.DstStructTypesSet.hasType(ST)) {
740 // This is actually a type from the destination module.
741 // getIdentifiedStructTypes() can have found it by walking debug info
742 // metadata nodes, some of which get linked by name when ODR Type Uniquing
743 // is enabled on the Context, from the source to the destination module.
744 continue;
745 }
746
747 auto STTypePrefix = getTypeNamePrefix(ST->getName());
748 if (STTypePrefix.size()== ST->getName().size())
749 continue;
750
751 // Check to see if the destination module has a struct with the prefix name.
752 StructType *DST = DstM.getTypeByName(STTypePrefix);
753 if (!DST)
754 continue;
755
756 // Don't use it if this actually came from the source module. They're in
757 // the same LLVMContext after all. Also don't use it unless the type is
758 // actually used in the destination module. This can happen in situations
759 // like this:
760 //
761 // Module A Module B
762 // -------- --------
763 // %Z = type { %A } %B = type { %C.1 }
764 // %A = type { %B.1, [7 x i8] } %C.1 = type { i8* }
765 // %B.1 = type { %C } %A.2 = type { %B.3, [5 x i8] }
766 // %C = type { i8* } %B.3 = type { %C.1 }
767 //
768 // When we link Module B with Module A, the '%B' in Module B is
769 // used. However, that would then use '%C.1'. But when we process '%C.1',
770 // we prefer to take the '%C' version. So we are then left with both
771 // '%C.1' and '%C' being used for the same types. This leads to some
772 // variables using one type and some using the other.
773 if (TypeMap.DstStructTypesSet.hasType(DST))
774 TypeMap.addTypeMapping(DST, ST);
775 }
776
777 // Now that we have discovered all of the type equivalences, get a body for
778 // any 'opaque' types in the dest module that are now resolved.
779 TypeMap.linkDefinedTypeBodies();
780}
781
782static void getArrayElements(const Constant *C,
783 SmallVectorImpl<Constant *> &Dest) {
784 unsigned NumElements = cast<ArrayType>(C->getType())->getNumElements();
785
786 for (unsigned i = 0; i != NumElements; ++i)
787 Dest.push_back(C->getAggregateElement(i));
788}
789
790/// If there were any appending global variables, link them together now.
791Expected<Constant *>
792IRLinker::linkAppendingVarProto(GlobalVariable *DstGV,
793 const GlobalVariable *SrcGV) {
794 Type *EltTy = cast<ArrayType>(TypeMap.get(SrcGV->getValueType()))
795 ->getElementType();
796
797 // FIXME: This upgrade is done during linking to support the C API. Once the
798 // old form is deprecated, we should move this upgrade to
799 // llvm::UpgradeGlobalVariable() and simplify the logic here and in
800 // Mapper::mapAppendingVariable() in ValueMapper.cpp.
801 StringRef Name = SrcGV->getName();
802 bool IsNewStructor = false;
803 bool IsOldStructor = false;
804 if (Name == "llvm.global_ctors" || Name == "llvm.global_dtors") {
9
Assuming the condition is false
10
Assuming the condition is false
11
Taking false branch
805 if (cast<StructType>(EltTy)->getNumElements() == 3)
806 IsNewStructor = true;
807 else
808 IsOldStructor = true;
809 }
810
811 PointerType *VoidPtrTy = Type::getInt8Ty(SrcGV->getContext())->getPointerTo();
812 if (IsOldStructor) {
12
Taking false branch
813 auto &ST = *cast<StructType>(EltTy);
814 Type *Tys[3] = {ST.getElementType(0), ST.getElementType(1), VoidPtrTy};
815 EltTy = StructType::get(SrcGV->getContext(), Tys, false);
816 }
817
818 uint64_t DstNumElements = 0;
819 if (DstGV) {
13
Taking true branch
820 ArrayType *DstTy = cast<ArrayType>(DstGV->getValueType());
821 DstNumElements = DstTy->getNumElements();
822
823 if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage())
14
Taking false branch
824 return stringErr(
825 "Linking globals named '" + SrcGV->getName() +
826 "': can only link appending global with another appending "
827 "global!");
828
829 // Check to see that they two arrays agree on type.
830 if (EltTy != DstTy->getElementType())
15
Assuming the condition is true
16
Taking true branch
831 return stringErr("Appending variables with different element types!");
17
Calling 'IRLinker::stringErr'
832 if (DstGV->isConstant() != SrcGV->isConstant())
833 return stringErr("Appending variables linked with different const'ness!");
834
835 if (DstGV->getAlignment() != SrcGV->getAlignment())
836 return stringErr(
837 "Appending variables with different alignment need to be linked!");
838
839 if (DstGV->getVisibility() != SrcGV->getVisibility())
840 return stringErr(
841 "Appending variables with different visibility need to be linked!");
842
843 if (DstGV->hasGlobalUnnamedAddr() != SrcGV->hasGlobalUnnamedAddr())
844 return stringErr(
845 "Appending variables with different unnamed_addr need to be linked!");
846
847 if (DstGV->getSection() != SrcGV->getSection())
848 return stringErr(
849 "Appending variables with different section name need to be linked!");
850 }
851
852 SmallVector<Constant *, 16> SrcElements;
853 getArrayElements(SrcGV->getInitializer(), SrcElements);
854
855 if (IsNewStructor) {
856 auto It = remove_if(SrcElements, [this](Constant *E) {
857 auto *Key =
858 dyn_cast<GlobalValue>(E->getAggregateElement(2)->stripPointerCasts());
859 if (!Key)
860 return false;
861 GlobalValue *DGV = getLinkedToGlobal(Key);
862 return !shouldLink(DGV, *Key);
863 });
864 SrcElements.erase(It, SrcElements.end());
865 }
866 uint64_t NewSize = DstNumElements + SrcElements.size();
867 ArrayType *NewType = ArrayType::get(EltTy, NewSize);
868
869 // Create the new global variable.
870 GlobalVariable *NG = new GlobalVariable(
871 DstM, NewType, SrcGV->isConstant(), SrcGV->getLinkage(),
872 /*init*/ nullptr, /*name*/ "", DstGV, SrcGV->getThreadLocalMode(),
873 SrcGV->getType()->getAddressSpace());
874
875 NG->copyAttributesFrom(SrcGV);
876 forceRenaming(NG, SrcGV->getName());
877
878 Constant *Ret = ConstantExpr::getBitCast(NG, TypeMap.get(SrcGV->getType()));
879
880 Mapper.scheduleMapAppendingVariable(*NG,
881 DstGV ? DstGV->getInitializer() : nullptr,
882 IsOldStructor, SrcElements);
883
884 // Replace any uses of the two global variables with uses of the new
885 // global.
886 if (DstGV) {
887 DstGV->replaceAllUsesWith(ConstantExpr::getBitCast(NG, DstGV->getType()));
888 DstGV->eraseFromParent();
889 }
890
891 return Ret;
892}
893
894bool IRLinker::shouldLink(GlobalValue *DGV, GlobalValue &SGV) {
895 if (ValuesToLink.count(&SGV) || SGV.hasLocalLinkage())
896 return true;
897
898 if (DGV && !DGV->isDeclarationForLinker())
899 return false;
900
901 if (SGV.isDeclaration() || DoneLinkingBodies)
902 return false;
903
904 // Callback to the client to give a chance to lazily add the Global to the
905 // list of value to link.
906 bool LazilyAdded = false;
907 AddLazyFor(SGV, [this, &LazilyAdded](GlobalValue &GV) {
908 maybeAdd(&GV);
909 LazilyAdded = true;
910 });
911 return LazilyAdded;
912}
913
914Expected<Constant *> IRLinker::linkGlobalValueProto(GlobalValue *SGV,
915 bool ForAlias) {
916 GlobalValue *DGV = getLinkedToGlobal(SGV);
917
918 bool ShouldLink = shouldLink(DGV, *SGV);
919
920 // just missing from map
921 if (ShouldLink) {
4
Assuming 'ShouldLink' is 0
5
Taking false branch
922 auto I = ValueMap.find(SGV);
923 if (I != ValueMap.end())
924 return cast<Constant>(I->second);
925
926 I = AliasValueMap.find(SGV);
927 if (I != AliasValueMap.end())
928 return cast<Constant>(I->second);
929 }
930
931 if (!ShouldLink && ForAlias)
6
Taking false branch
932 DGV = nullptr;
933
934 // Handle the ultra special appending linkage case first.
935 assert(!DGV || SGV->hasAppendingLinkage() == DGV->hasAppendingLinkage())((!DGV || SGV->hasAppendingLinkage() == DGV->hasAppendingLinkage
()) ? static_cast<void> (0) : __assert_fail ("!DGV || SGV->hasAppendingLinkage() == DGV->hasAppendingLinkage()"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 935, __PRETTY_FUNCTION__))
;
936 if (SGV->hasAppendingLinkage())
7
Taking true branch
937 return linkAppendingVarProto(cast_or_null<GlobalVariable>(DGV),
8
Calling 'IRLinker::linkAppendingVarProto'
938 cast<GlobalVariable>(SGV));
939
940 GlobalValue *NewGV;
941 if (DGV && !ShouldLink) {
942 NewGV = DGV;
943 } else {
944 // If we are done linking global value bodies (i.e. we are performing
945 // metadata linking), don't link in the global value due to this
946 // reference, simply map it to null.
947 if (DoneLinkingBodies)
948 return nullptr;
949
950 NewGV = copyGlobalValueProto(SGV, ShouldLink || ForAlias);
951 if (ShouldLink || !ForAlias)
952 forceRenaming(NewGV, SGV->getName());
953 }
954
955 // Overloaded intrinsics have overloaded types names as part of their
956 // names. If we renamed overloaded types we should rename the intrinsic
957 // as well.
958 if (Function *F = dyn_cast<Function>(NewGV))
959 if (auto Remangled = Intrinsic::remangleIntrinsicFunction(F))
960 NewGV = Remangled.getValue();
961
962 if (ShouldLink || ForAlias) {
963 if (const Comdat *SC = SGV->getComdat()) {
964 if (auto *GO = dyn_cast<GlobalObject>(NewGV)) {
965 Comdat *DC = DstM.getOrInsertComdat(SC->getName());
966 DC->setSelectionKind(SC->getSelectionKind());
967 GO->setComdat(DC);
968 }
969 }
970 }
971
972 if (!ShouldLink && ForAlias)
973 NewGV->setLinkage(GlobalValue::InternalLinkage);
974
975 Constant *C = NewGV;
976 // Only create a bitcast if necessary. In particular, with
977 // DebugTypeODRUniquing we may reach metadata in the destination module
978 // containing a GV from the source module, in which case SGV will be
979 // the same as DGV and NewGV, and TypeMap.get() will assert since it
980 // assumes it is being invoked on a type in the source module.
981 if (DGV && NewGV != SGV) {
982 C = ConstantExpr::getPointerBitCastOrAddrSpaceCast(
983 NewGV, TypeMap.get(SGV->getType()));
984 }
985
986 if (DGV && NewGV != DGV) {
987 DGV->replaceAllUsesWith(
988 ConstantExpr::getPointerBitCastOrAddrSpaceCast(NewGV, DGV->getType()));
989 DGV->eraseFromParent();
990 }
991
992 return C;
993}
994
995/// Update the initializers in the Dest module now that all globals that may be
996/// referenced are in Dest.
997void IRLinker::linkGlobalVariable(GlobalVariable &Dst, GlobalVariable &Src) {
998 // Figure out what the initializer looks like in the dest module.
999 Mapper.scheduleMapGlobalInitializer(Dst, *Src.getInitializer());
1000}
1001
1002/// Copy the source function over into the dest function and fix up references
1003/// to values. At this point we know that Dest is an external function, and
1004/// that Src is not.
1005Error IRLinker::linkFunctionBody(Function &Dst, Function &Src) {
1006 assert(Dst.isDeclaration() && !Src.isDeclaration())((Dst.isDeclaration() && !Src.isDeclaration()) ? static_cast
<void> (0) : __assert_fail ("Dst.isDeclaration() && !Src.isDeclaration()"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 1006, __PRETTY_FUNCTION__))
;
1007
1008 // Materialize if needed.
1009 if (Error Err = Src.materialize())
1010 return Err;
1011
1012 // Link in the operands without remapping.
1013 if (Src.hasPrefixData())
1014 Dst.setPrefixData(Src.getPrefixData());
1015 if (Src.hasPrologueData())
1016 Dst.setPrologueData(Src.getPrologueData());
1017 if (Src.hasPersonalityFn())
1018 Dst.setPersonalityFn(Src.getPersonalityFn());
1019
1020 // Copy over the metadata attachments without remapping.
1021 Dst.copyMetadata(&Src, 0);
1022
1023 // Steal arguments and splice the body of Src into Dst.
1024 Dst.stealArgumentListFrom(Src);
1025 Dst.getBasicBlockList().splice(Dst.end(), Src.getBasicBlockList());
1026
1027 // Everything has been moved over. Remap it.
1028 Mapper.scheduleRemapFunction(Dst);
1029 return Error::success();
1030}
1031
1032void IRLinker::linkAliasBody(GlobalAlias &Dst, GlobalAlias &Src) {
1033 Mapper.scheduleMapGlobalAliasee(Dst, *Src.getAliasee(), AliasMCID);
1034}
1035
1036Error IRLinker::linkGlobalValueBody(GlobalValue &Dst, GlobalValue &Src) {
1037 if (auto *F = dyn_cast<Function>(&Src))
1038 return linkFunctionBody(cast<Function>(Dst), *F);
1039 if (auto *GVar = dyn_cast<GlobalVariable>(&Src)) {
1040 linkGlobalVariable(cast<GlobalVariable>(Dst), *GVar);
1041 return Error::success();
1042 }
1043 linkAliasBody(cast<GlobalAlias>(Dst), cast<GlobalAlias>(Src));
1044 return Error::success();
1045}
1046
1047void IRLinker::prepareCompileUnitsForImport() {
1048 NamedMDNode *SrcCompileUnits = SrcM->getNamedMetadata("llvm.dbg.cu");
1049 if (!SrcCompileUnits)
1050 return;
1051 // When importing for ThinLTO, prevent importing of types listed on
1052 // the DICompileUnit that we don't need a copy of in the importing
1053 // module. They will be emitted by the originating module.
1054 for (unsigned I = 0, E = SrcCompileUnits->getNumOperands(); I != E; ++I) {
1055 auto *CU = cast<DICompileUnit>(SrcCompileUnits->getOperand(I));
1056 assert(CU && "Expected valid compile unit")((CU && "Expected valid compile unit") ? static_cast<
void> (0) : __assert_fail ("CU && \"Expected valid compile unit\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 1056, __PRETTY_FUNCTION__))
;
1057 // Enums, macros, and retained types don't need to be listed on the
1058 // imported DICompileUnit. This means they will only be imported
1059 // if reached from the mapped IR. Do this by setting their value map
1060 // entries to nullptr, which will automatically prevent their importing
1061 // when reached from the DICompileUnit during metadata mapping.
1062 ValueMap.MD()[CU->getRawEnumTypes()].reset(nullptr);
1063 ValueMap.MD()[CU->getRawMacros()].reset(nullptr);
1064 ValueMap.MD()[CU->getRawRetainedTypes()].reset(nullptr);
1065 // We import global variables only temporarily in order for instcombine
1066 // and globalopt to perform constant folding and static constructor
1067 // evaluation. After that elim-avail-extern will covert imported globals
1068 // back to declarations, so we don't need debug info for them.
1069 ValueMap.MD()[CU->getRawGlobalVariables()].reset(nullptr);
1070
1071 // Imported entities only need to be mapped in if they have local
1072 // scope, as those might correspond to an imported entity inside a
1073 // function being imported (any locally scoped imported entities that
1074 // don't end up referenced by an imported function will not be emitted
1075 // into the object). Imported entities not in a local scope
1076 // (e.g. on the namespace) only need to be emitted by the originating
1077 // module. Create a list of the locally scoped imported entities, and
1078 // replace the source CUs imported entity list with the new list, so
1079 // only those are mapped in.
1080 // FIXME: Locally-scoped imported entities could be moved to the
1081 // functions they are local to instead of listing them on the CU, and
1082 // we would naturally only link in those needed by function importing.
1083 SmallVector<TrackingMDNodeRef, 4> AllImportedModules;
1084 bool ReplaceImportedEntities = false;
1085 for (auto *IE : CU->getImportedEntities()) {
1086 DIScope *Scope = IE->getScope();
1087 assert(Scope && "Invalid Scope encoding!")((Scope && "Invalid Scope encoding!") ? static_cast<
void> (0) : __assert_fail ("Scope && \"Invalid Scope encoding!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 1087, __PRETTY_FUNCTION__))
;
1088 if (isa<DILocalScope>(Scope))
1089 AllImportedModules.emplace_back(IE);
1090 else
1091 ReplaceImportedEntities = true;
1092 }
1093 if (ReplaceImportedEntities) {
1094 if (!AllImportedModules.empty())
1095 CU->replaceImportedEntities(MDTuple::get(
1096 CU->getContext(),
1097 SmallVector<Metadata *, 16>(AllImportedModules.begin(),
1098 AllImportedModules.end())));
1099 else
1100 // If there were no local scope imported entities, we can map
1101 // the whole list to nullptr.
1102 ValueMap.MD()[CU->getRawImportedEntities()].reset(nullptr);
1103 }
1104 }
1105}
1106
1107/// Insert all of the named MDNodes in Src into the Dest module.
1108void IRLinker::linkNamedMDNodes() {
1109 const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
1110 for (const NamedMDNode &NMD : SrcM->named_metadata()) {
1111 // Don't link module flags here. Do them separately.
1112 if (&NMD == SrcModFlags)
1113 continue;
1114 NamedMDNode *DestNMD = DstM.getOrInsertNamedMetadata(NMD.getName());
1115 // Add Src elements into Dest node.
1116 for (const MDNode *Op : NMD.operands())
1117 DestNMD->addOperand(Mapper.mapMDNode(*Op));
1118 }
1119}
1120
1121/// Merge the linker flags in Src into the Dest module.
1122Error IRLinker::linkModuleFlagsMetadata() {
1123 // If the source module has no module flags, we are done.
1124 const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
1125 if (!SrcModFlags)
1126 return Error::success();
1127
1128 // If the destination module doesn't have module flags yet, then just copy
1129 // over the source module's flags.
1130 NamedMDNode *DstModFlags = DstM.getOrInsertModuleFlagsMetadata();
1131 if (DstModFlags->getNumOperands() == 0) {
1132 for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
1133 DstModFlags->addOperand(SrcModFlags->getOperand(I));
1134
1135 return Error::success();
1136 }
1137
1138 // First build a map of the existing module flags and requirements.
1139 DenseMap<MDString *, std::pair<MDNode *, unsigned>> Flags;
1140 SmallSetVector<MDNode *, 16> Requirements;
1141 for (unsigned I = 0, E = DstModFlags->getNumOperands(); I != E; ++I) {
1142 MDNode *Op = DstModFlags->getOperand(I);
1143 ConstantInt *Behavior = mdconst::extract<ConstantInt>(Op->getOperand(0));
1144 MDString *ID = cast<MDString>(Op->getOperand(1));
1145
1146 if (Behavior->getZExtValue() == Module::Require) {
1147 Requirements.insert(cast<MDNode>(Op->getOperand(2)));
1148 } else {
1149 Flags[ID] = std::make_pair(Op, I);
1150 }
1151 }
1152
1153 // Merge in the flags from the source module, and also collect its set of
1154 // requirements.
1155 for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I) {
1156 MDNode *SrcOp = SrcModFlags->getOperand(I);
1157 ConstantInt *SrcBehavior =
1158 mdconst::extract<ConstantInt>(SrcOp->getOperand(0));
1159 MDString *ID = cast<MDString>(SrcOp->getOperand(1));
1160 MDNode *DstOp;
1161 unsigned DstIndex;
1162 std::tie(DstOp, DstIndex) = Flags.lookup(ID);
1163 unsigned SrcBehaviorValue = SrcBehavior->getZExtValue();
1164
1165 // If this is a requirement, add it and continue.
1166 if (SrcBehaviorValue == Module::Require) {
1167 // If the destination module does not already have this requirement, add
1168 // it.
1169 if (Requirements.insert(cast<MDNode>(SrcOp->getOperand(2)))) {
1170 DstModFlags->addOperand(SrcOp);
1171 }
1172 continue;
1173 }
1174
1175 // If there is no existing flag with this ID, just add it.
1176 if (!DstOp) {
1177 Flags[ID] = std::make_pair(SrcOp, DstModFlags->getNumOperands());
1178 DstModFlags->addOperand(SrcOp);
1179 continue;
1180 }
1181
1182 // Otherwise, perform a merge.
1183 ConstantInt *DstBehavior =
1184 mdconst::extract<ConstantInt>(DstOp->getOperand(0));
1185 unsigned DstBehaviorValue = DstBehavior->getZExtValue();
1186
1187 auto overrideDstValue = [&]() {
1188 DstModFlags->setOperand(DstIndex, SrcOp);
1189 Flags[ID].first = SrcOp;
1190 };
1191
1192 // If either flag has override behavior, handle it first.
1193 if (DstBehaviorValue == Module::Override) {
1194 // Diagnose inconsistent flags which both have override behavior.
1195 if (SrcBehaviorValue == Module::Override &&
1196 SrcOp->getOperand(2) != DstOp->getOperand(2))
1197 return stringErr("linking module flags '" + ID->getString() +
1198 "': IDs have conflicting override values");
1199 continue;
1200 } else if (SrcBehaviorValue == Module::Override) {
1201 // Update the destination flag to that of the source.
1202 overrideDstValue();
1203 continue;
1204 }
1205
1206 // Diagnose inconsistent merge behavior types.
1207 if (SrcBehaviorValue != DstBehaviorValue)
1208 return stringErr("linking module flags '" + ID->getString() +
1209 "': IDs have conflicting behaviors");
1210
1211 auto replaceDstValue = [&](MDNode *New) {
1212 Metadata *FlagOps[] = {DstOp->getOperand(0), ID, New};
1213 MDNode *Flag = MDNode::get(DstM.getContext(), FlagOps);
1214 DstModFlags->setOperand(DstIndex, Flag);
1215 Flags[ID].first = Flag;
1216 };
1217
1218 // Perform the merge for standard behavior types.
1219 switch (SrcBehaviorValue) {
1220 case Module::Require:
1221 case Module::Override:
1222 llvm_unreachable("not possible")::llvm::llvm_unreachable_internal("not possible", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 1222)
;
1223 case Module::Error: {
1224 // Emit an error if the values differ.
1225 if (SrcOp->getOperand(2) != DstOp->getOperand(2))
1226 return stringErr("linking module flags '" + ID->getString() +
1227 "': IDs have conflicting values");
1228 continue;
1229 }
1230 case Module::Warning: {
1231 // Emit a warning if the values differ.
1232 if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
1233 std::string str;
1234 raw_string_ostream(str)
1235 << "linking module flags '" << ID->getString()
1236 << "': IDs have conflicting values ('" << *SrcOp->getOperand(2)
1237 << "' from " << SrcM->getModuleIdentifier() << " with '"
1238 << *DstOp->getOperand(2) << "' from " << DstM.getModuleIdentifier()
1239 << ')';
1240 emitWarning(str);
1241 }
1242 continue;
1243 }
1244 case Module::Max: {
1245 ConstantInt *DstValue =
1246 mdconst::extract<ConstantInt>(DstOp->getOperand(2));
1247 ConstantInt *SrcValue =
1248 mdconst::extract<ConstantInt>(SrcOp->getOperand(2));
1249 if (SrcValue->getZExtValue() > DstValue->getZExtValue())
1250 overrideDstValue();
1251 break;
1252 }
1253 case Module::Append: {
1254 MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
1255 MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
1256 SmallVector<Metadata *, 8> MDs;
1257 MDs.reserve(DstValue->getNumOperands() + SrcValue->getNumOperands());
1258 MDs.append(DstValue->op_begin(), DstValue->op_end());
1259 MDs.append(SrcValue->op_begin(), SrcValue->op_end());
1260
1261 replaceDstValue(MDNode::get(DstM.getContext(), MDs));
1262 break;
1263 }
1264 case Module::AppendUnique: {
1265 SmallSetVector<Metadata *, 16> Elts;
1266 MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
1267 MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
1268 Elts.insert(DstValue->op_begin(), DstValue->op_end());
1269 Elts.insert(SrcValue->op_begin(), SrcValue->op_end());
1270
1271 replaceDstValue(MDNode::get(DstM.getContext(),
1272 makeArrayRef(Elts.begin(), Elts.end())));
1273 break;
1274 }
1275 }
1276 }
1277
1278 // Check all of the requirements.
1279 for (unsigned I = 0, E = Requirements.size(); I != E; ++I) {
1280 MDNode *Requirement = Requirements[I];
1281 MDString *Flag = cast<MDString>(Requirement->getOperand(0));
1282 Metadata *ReqValue = Requirement->getOperand(1);
1283
1284 MDNode *Op = Flags[Flag].first;
1285 if (!Op || Op->getOperand(2) != ReqValue)
1286 return stringErr("linking module flags '" + Flag->getString() +
1287 "': does not have the required value");
1288 }
1289 return Error::success();
1290}
1291
1292/// Return InlineAsm adjusted with target-specific directives if required.
1293/// For ARM and Thumb, we have to add directives to select the appropriate ISA
1294/// to support mixing module-level inline assembly from ARM and Thumb modules.
1295static std::string adjustInlineAsm(const std::string &InlineAsm,
1296 const Triple &Triple) {
1297 if (Triple.getArch() == Triple::thumb || Triple.getArch() == Triple::thumbeb)
1298 return ".text\n.balign 2\n.thumb\n" + InlineAsm;
1299 if (Triple.getArch() == Triple::arm || Triple.getArch() == Triple::armeb)
1300 return ".text\n.balign 4\n.arm\n" + InlineAsm;
1301 return InlineAsm;
1302}
1303
1304Error IRLinker::run() {
1305 // Ensure metadata materialized before value mapping.
1306 if (SrcM->getMaterializer())
1307 if (Error Err = SrcM->getMaterializer()->materializeMetadata())
1308 return Err;
1309
1310 // Inherit the target data from the source module if the destination module
1311 // doesn't have one already.
1312 if (DstM.getDataLayout().isDefault())
1313 DstM.setDataLayout(SrcM->getDataLayout());
1314
1315 if (SrcM->getDataLayout() != DstM.getDataLayout()) {
1316 emitWarning("Linking two modules of different data layouts: '" +
1317 SrcM->getModuleIdentifier() + "' is '" +
1318 SrcM->getDataLayoutStr() + "' whereas '" +
1319 DstM.getModuleIdentifier() + "' is '" +
1320 DstM.getDataLayoutStr() + "'\n");
1321 }
1322
1323 // Copy the target triple from the source to dest if the dest's is empty.
1324 if (DstM.getTargetTriple().empty() && !SrcM->getTargetTriple().empty())
1325 DstM.setTargetTriple(SrcM->getTargetTriple());
1326
1327 Triple SrcTriple(SrcM->getTargetTriple()), DstTriple(DstM.getTargetTriple());
1328
1329 if (!SrcM->getTargetTriple().empty()&&
1330 !SrcTriple.isCompatibleWith(DstTriple))
1331 emitWarning("Linking two modules of different target triples: " +
1332 SrcM->getModuleIdentifier() + "' is '" +
1333 SrcM->getTargetTriple() + "' whereas '" +
1334 DstM.getModuleIdentifier() + "' is '" + DstM.getTargetTriple() +
1335 "'\n");
1336
1337 DstM.setTargetTriple(SrcTriple.merge(DstTriple));
1338
1339 // Append the module inline asm string.
1340 if (!IsPerformingImport && !SrcM->getModuleInlineAsm().empty()) {
1341 std::string SrcModuleInlineAsm = adjustInlineAsm(SrcM->getModuleInlineAsm(),
1342 SrcTriple);
1343 if (DstM.getModuleInlineAsm().empty())
1344 DstM.setModuleInlineAsm(SrcModuleInlineAsm);
1345 else
1346 DstM.setModuleInlineAsm(DstM.getModuleInlineAsm() + "\n" +
1347 SrcModuleInlineAsm);
1348 }
1349
1350 // Loop over all of the linked values to compute type mappings.
1351 computeTypeMapping();
1352
1353 std::reverse(Worklist.begin(), Worklist.end());
1354 while (!Worklist.empty()) {
1355 GlobalValue *GV = Worklist.back();
1356 Worklist.pop_back();
1357
1358 // Already mapped.
1359 if (ValueMap.find(GV) != ValueMap.end() ||
1360 AliasValueMap.find(GV) != AliasValueMap.end())
1361 continue;
1362
1363 assert(!GV->isDeclaration())((!GV->isDeclaration()) ? static_cast<void> (0) : __assert_fail
("!GV->isDeclaration()", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 1363, __PRETTY_FUNCTION__))
;
1364 Mapper.mapValue(*GV);
1365 if (FoundError)
1366 return std::move(*FoundError);
1367 }
1368
1369 // Note that we are done linking global value bodies. This prevents
1370 // metadata linking from creating new references.
1371 DoneLinkingBodies = true;
1372 Mapper.addFlags(RF_NullMapMissingGlobalValues);
1373
1374 // Remap all of the named MDNodes in Src into the DstM module. We do this
1375 // after linking GlobalValues so that MDNodes that reference GlobalValues
1376 // are properly remapped.
1377 linkNamedMDNodes();
1378
1379 // Merge the module flags into the DstM module.
1380 return linkModuleFlagsMetadata();
1381}
1382
1383IRMover::StructTypeKeyInfo::KeyTy::KeyTy(ArrayRef<Type *> E, bool P)
1384 : ETypes(E), IsPacked(P) {}
1385
1386IRMover::StructTypeKeyInfo::KeyTy::KeyTy(const StructType *ST)
1387 : ETypes(ST->elements()), IsPacked(ST->isPacked()) {}
1388
1389bool IRMover::StructTypeKeyInfo::KeyTy::operator==(const KeyTy &That) const {
1390 return IsPacked == That.IsPacked && ETypes == That.ETypes;
1391}
1392
1393bool IRMover::StructTypeKeyInfo::KeyTy::operator!=(const KeyTy &That) const {
1394 return !this->operator==(That);
1395}
1396
1397StructType *IRMover::StructTypeKeyInfo::getEmptyKey() {
1398 return DenseMapInfo<StructType *>::getEmptyKey();
1399}
1400
1401StructType *IRMover::StructTypeKeyInfo::getTombstoneKey() {
1402 return DenseMapInfo<StructType *>::getTombstoneKey();
1403}
1404
1405unsigned IRMover::StructTypeKeyInfo::getHashValue(const KeyTy &Key) {
1406 return hash_combine(hash_combine_range(Key.ETypes.begin(), Key.ETypes.end()),
1407 Key.IsPacked);
1408}
1409
1410unsigned IRMover::StructTypeKeyInfo::getHashValue(const StructType *ST) {
1411 return getHashValue(KeyTy(ST));
1412}
1413
1414bool IRMover::StructTypeKeyInfo::isEqual(const KeyTy &LHS,
1415 const StructType *RHS) {
1416 if (RHS == getEmptyKey() || RHS == getTombstoneKey())
1417 return false;
1418 return LHS == KeyTy(RHS);
1419}
1420
1421bool IRMover::StructTypeKeyInfo::isEqual(const StructType *LHS,
1422 const StructType *RHS) {
1423 if (RHS == getEmptyKey() || RHS == getTombstoneKey())
1424 return LHS == RHS;
1425 return KeyTy(LHS) == KeyTy(RHS);
1426}
1427
1428void IRMover::IdentifiedStructTypeSet::addNonOpaque(StructType *Ty) {
1429 assert(!Ty->isOpaque())((!Ty->isOpaque()) ? static_cast<void> (0) : __assert_fail
("!Ty->isOpaque()", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 1429, __PRETTY_FUNCTION__))
;
1430 NonOpaqueStructTypes.insert(Ty);
1431}
1432
1433void IRMover::IdentifiedStructTypeSet::switchToNonOpaque(StructType *Ty) {
1434 assert(!Ty->isOpaque())((!Ty->isOpaque()) ? static_cast<void> (0) : __assert_fail
("!Ty->isOpaque()", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 1434, __PRETTY_FUNCTION__))
;
1435 NonOpaqueStructTypes.insert(Ty);
1436 bool Removed = OpaqueStructTypes.erase(Ty);
1437 (void)Removed;
1438 assert(Removed)((Removed) ? static_cast<void> (0) : __assert_fail ("Removed"
, "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 1438, __PRETTY_FUNCTION__))
;
1439}
1440
1441void IRMover::IdentifiedStructTypeSet::addOpaque(StructType *Ty) {
1442 assert(Ty->isOpaque())((Ty->isOpaque()) ? static_cast<void> (0) : __assert_fail
("Ty->isOpaque()", "/build/llvm-toolchain-snapshot-8~svn345461/lib/Linker/IRMover.cpp"
, 1442, __PRETTY_FUNCTION__))
;
1443 OpaqueStructTypes.insert(Ty);
1444}
1445
1446StructType *
1447IRMover::IdentifiedStructTypeSet::findNonOpaque(ArrayRef<Type *> ETypes,
1448 bool IsPacked) {
1449 IRMover::StructTypeKeyInfo::KeyTy Key(ETypes, IsPacked);
1450 auto I = NonOpaqueStructTypes.find_as(Key);
1451 return I == NonOpaqueStructTypes.end() ? nullptr : *I;
1452}
1453
1454bool IRMover::IdentifiedStructTypeSet::hasType(StructType *Ty) {
1455 if (Ty->isOpaque())
1456 return OpaqueStructTypes.count(Ty);
1457 auto I = NonOpaqueStructTypes.find(Ty);
1458 return I == NonOpaqueStructTypes.end() ? false : *I == Ty;
1459}
1460
1461IRMover::IRMover(Module &M) : Composite(M) {
1462 TypeFinder StructTypes;
1463 StructTypes.run(M, /* OnlyNamed */ false);
1464 for (StructType *Ty : StructTypes) {
1465 if (Ty->isOpaque())
1466 IdentifiedStructTypes.addOpaque(Ty);
1467 else
1468 IdentifiedStructTypes.addNonOpaque(Ty);
1469 }
1470 // Self-map metadatas in the destination module. This is needed when
1471 // DebugTypeODRUniquing is enabled on the LLVMContext, since metadata in the
1472 // destination module may be reached from the source module.
1473 for (auto *MD : StructTypes.getVisitedMetadata()) {
1474 SharedMDs[MD].reset(const_cast<MDNode *>(MD));
1475 }
1476}
1477
1478Error IRMover::move(
1479 std::unique_ptr<Module> Src, ArrayRef<GlobalValue *> ValuesToLink,
1480 std::function<void(GlobalValue &, ValueAdder Add)> AddLazyFor,
1481 bool IsPerformingImport) {
1482 IRLinker TheIRLinker(Composite, SharedMDs, IdentifiedStructTypes,
1483 std::move(Src), ValuesToLink, std::move(AddLazyFor),
1484 IsPerformingImport);
1485 Error E = TheIRLinker.run();
1486 Composite.dropTriviallyDeadConstantArrays();
1487 return E;
1488}

/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h

1//===- llvm/Support/Error.h - Recoverable error handling --------*- C++ -*-===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines an API used to report recoverable errors.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_SUPPORT_ERROR_H
15#define LLVM_SUPPORT_ERROR_H
16
17#include "llvm-c/Error.h"
18#include "llvm/ADT/STLExtras.h"
19#include "llvm/ADT/SmallVector.h"
20#include "llvm/ADT/StringExtras.h"
21#include "llvm/ADT/Twine.h"
22#include "llvm/Config/abi-breaking.h"
23#include "llvm/Support/AlignOf.h"
24#include "llvm/Support/Compiler.h"
25#include "llvm/Support/Debug.h"
26#include "llvm/Support/ErrorHandling.h"
27#include "llvm/Support/ErrorOr.h"
28#include "llvm/Support/Format.h"
29#include "llvm/Support/raw_ostream.h"
30#include <algorithm>
31#include <cassert>
32#include <cstdint>
33#include <cstdlib>
34#include <functional>
35#include <memory>
36#include <new>
37#include <string>
38#include <system_error>
39#include <type_traits>
40#include <utility>
41#include <vector>
42
43namespace llvm {
44
45class ErrorSuccess;
46
47/// Base class for error info classes. Do not extend this directly: Extend
48/// the ErrorInfo template subclass instead.
49class ErrorInfoBase {
50public:
51 virtual ~ErrorInfoBase() = default;
52
53 /// Print an error message to an output stream.
54 virtual void log(raw_ostream &OS) const = 0;
55
56 /// Return the error message as a string.
57 virtual std::string message() const {
58 std::string Msg;
59 raw_string_ostream OS(Msg);
60 log(OS);
61 return OS.str();
62 }
63
64 /// Convert this error to a std::error_code.
65 ///
66 /// This is a temporary crutch to enable interaction with code still
67 /// using std::error_code. It will be removed in the future.
68 virtual std::error_code convertToErrorCode() const = 0;
69
70 // Returns the class ID for this type.
71 static const void *classID() { return &ID; }
72
73 // Returns the class ID for the dynamic type of this ErrorInfoBase instance.
74 virtual const void *dynamicClassID() const = 0;
75
76 // Check whether this instance is a subclass of the class identified by
77 // ClassID.
78 virtual bool isA(const void *const ClassID) const {
79 return ClassID == classID();
80 }
81
82 // Check whether this instance is a subclass of ErrorInfoT.
83 template <typename ErrorInfoT> bool isA() const {
84 return isA(ErrorInfoT::classID());
85 }
86
87private:
88 virtual void anchor();
89
90 static char ID;
91};
92
93/// Lightweight error class with error context and mandatory checking.
94///
95/// Instances of this class wrap a ErrorInfoBase pointer. Failure states
96/// are represented by setting the pointer to a ErrorInfoBase subclass
97/// instance containing information describing the failure. Success is
98/// represented by a null pointer value.
99///
100/// Instances of Error also contains a 'Checked' flag, which must be set
101/// before the destructor is called, otherwise the destructor will trigger a
102/// runtime error. This enforces at runtime the requirement that all Error
103/// instances be checked or returned to the caller.
104///
105/// There are two ways to set the checked flag, depending on what state the
106/// Error instance is in. For Error instances indicating success, it
107/// is sufficient to invoke the boolean conversion operator. E.g.:
108///
109/// @code{.cpp}
110/// Error foo(<...>);
111///
112/// if (auto E = foo(<...>))
113/// return E; // <- Return E if it is in the error state.
114/// // We have verified that E was in the success state. It can now be safely
115/// // destroyed.
116/// @endcode
117///
118/// A success value *can not* be dropped. For example, just calling 'foo(<...>)'
119/// without testing the return value will raise a runtime error, even if foo
120/// returns success.
121///
122/// For Error instances representing failure, you must use either the
123/// handleErrors or handleAllErrors function with a typed handler. E.g.:
124///
125/// @code{.cpp}
126/// class MyErrorInfo : public ErrorInfo<MyErrorInfo> {
127/// // Custom error info.
128/// };
129///
130/// Error foo(<...>) { return make_error<MyErrorInfo>(...); }
131///
132/// auto E = foo(<...>); // <- foo returns failure with MyErrorInfo.
133/// auto NewE =
134/// handleErrors(E,
135/// [](const MyErrorInfo &M) {
136/// // Deal with the error.
137/// },
138/// [](std::unique_ptr<OtherError> M) -> Error {
139/// if (canHandle(*M)) {
140/// // handle error.
141/// return Error::success();
142/// }
143/// // Couldn't handle this error instance. Pass it up the stack.
144/// return Error(std::move(M));
145/// );
146/// // Note - we must check or return NewE in case any of the handlers
147/// // returned a new error.
148/// @endcode
149///
150/// The handleAllErrors function is identical to handleErrors, except
151/// that it has a void return type, and requires all errors to be handled and
152/// no new errors be returned. It prevents errors (assuming they can all be
153/// handled) from having to be bubbled all the way to the top-level.
154///
155/// *All* Error instances must be checked before destruction, even if
156/// they're moved-assigned or constructed from Success values that have already
157/// been checked. This enforces checking through all levels of the call stack.
158class LLVM_NODISCARD[[clang::warn_unused_result]] Error {
159 // Both ErrorList and FileError need to be able to yank ErrorInfoBase
160 // pointers out of this class to add to the error list.
161 friend class ErrorList;
162 friend class FileError;
163
164 // handleErrors needs to be able to set the Checked flag.
165 template <typename... HandlerTs>
166 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
167
168 // Expected<T> needs to be able to steal the payload when constructed from an
169 // error.
170 template <typename T> friend class Expected;
171
172 // wrap needs to be able to steal the payload.
173 friend LLVMErrorRef wrap(Error);
174
175protected:
176 /// Create a success value. Prefer using 'Error::success()' for readability
177 Error() {
178 setPtr(nullptr);
179 setChecked(false);
180 }
181
182public:
183 /// Create a success value.
184 static ErrorSuccess success();
185
186 // Errors are not copy-constructable.
187 Error(const Error &Other) = delete;
188
189 /// Move-construct an error value. The newly constructed error is considered
190 /// unchecked, even if the source error had been checked. The original error
191 /// becomes a checked Success value, regardless of its original state.
192 Error(Error &&Other) {
193 setChecked(true);
194 *this = std::move(Other);
195 }
196
197 /// Create an error value. Prefer using the 'make_error' function, but
198 /// this constructor can be useful when "re-throwing" errors from handlers.
199 Error(std::unique_ptr<ErrorInfoBase> Payload) {
200 setPtr(Payload.release());
201 setChecked(false);
23
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'
202 }
203
204 // Errors are not copy-assignable.
205 Error &operator=(const Error &Other) = delete;
206
207 /// Move-assign an error value. The current error must represent success, you
208 /// you cannot overwrite an unhandled error. The current error is then
209 /// considered unchecked. The source error becomes a checked success value,
210 /// regardless of its original state.
211 Error &operator=(Error &&Other) {
212 // Don't allow overwriting of unchecked values.
213 assertIsChecked();
214 setPtr(Other.getPtr());
215
216 // This Error is unchecked, even if the source error was checked.
217 setChecked(false);
218
219 // Null out Other's payload and set its checked bit.
220 Other.setPtr(nullptr);
221 Other.setChecked(true);
222
223 return *this;
224 }
225
226 /// Destroy a Error. Fails with a call to abort() if the error is
227 /// unchecked.
228 ~Error() {
229 assertIsChecked();
230 delete getPtr();
231 }
232
233 /// Bool conversion. Returns true if this Error is in a failure state,
234 /// and false if it is in an accept state. If the error is in a Success state
235 /// it will be considered checked.
236 explicit operator bool() {
237 setChecked(getPtr() == nullptr);
238 return getPtr() != nullptr;
239 }
240
241 /// Check whether one error is a subclass of another.
242 template <typename ErrT> bool isA() const {
243 return getPtr() && getPtr()->isA(ErrT::classID());
244 }
245
246 /// Returns the dynamic class id of this error, or null if this is a success
247 /// value.
248 const void* dynamicClassID() const {
249 if (!getPtr())
250 return nullptr;
251 return getPtr()->dynamicClassID();
252 }
253
254private:
255#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
256 // assertIsChecked() happens very frequently, but under normal circumstances
257 // is supposed to be a no-op. So we want it to be inlined, but having a bunch
258 // of debug prints can cause the function to be too large for inlining. So
259 // it's important that we define this function out of line so that it can't be
260 // inlined.
261 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
262 void fatalUncheckedError() const;
263#endif
264
265 void assertIsChecked() {
266#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
267 if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false))
268 fatalUncheckedError();
269#endif
270 }
271
272 ErrorInfoBase *getPtr() const {
273 return reinterpret_cast<ErrorInfoBase*>(
274 reinterpret_cast<uintptr_t>(Payload) &
275 ~static_cast<uintptr_t>(0x1));
276 }
277
278 void setPtr(ErrorInfoBase *EI) {
279#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
280 Payload = reinterpret_cast<ErrorInfoBase*>(
281 (reinterpret_cast<uintptr_t>(EI) &
282 ~static_cast<uintptr_t>(0x1)) |
283 (reinterpret_cast<uintptr_t>(Payload) & 0x1));
284#else
285 Payload = EI;
286#endif
287 }
288
289 bool getChecked() const {
290#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
291 return (reinterpret_cast<uintptr_t>(Payload) & 0x1) == 0;
292#else
293 return true;
294#endif
295 }
296
297 void setChecked(bool V) {
298 Payload = reinterpret_cast<ErrorInfoBase*>(
299 (reinterpret_cast<uintptr_t>(Payload) &
300 ~static_cast<uintptr_t>(0x1)) |
301 (V ? 0 : 1));
302 }
303
304 std::unique_ptr<ErrorInfoBase> takePayload() {
305 std::unique_ptr<ErrorInfoBase> Tmp(getPtr());
306 setPtr(nullptr);
307 setChecked(true);
308 return Tmp;
309 }
310
311 friend raw_ostream &operator<<(raw_ostream &OS, const Error &E) {
312 if (auto P = E.getPtr())
313 P->log(OS);
314 else
315 OS << "success";
316 return OS;
317 }
318
319 ErrorInfoBase *Payload = nullptr;
320};
321
322/// Subclass of Error for the sole purpose of identifying the success path in
323/// the type system. This allows to catch invalid conversion to Expected<T> at
324/// compile time.
325class ErrorSuccess final : public Error {};
326
327inline ErrorSuccess Error::success() { return ErrorSuccess(); }
328
329/// Make a Error instance representing failure using the given error info
330/// type.
331template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) {
332 return Error(llvm::make_unique<ErrT>(std::forward<ArgTs>(Args)...));
19
Calling 'make_unique<llvm::StringError, const llvm::Twine &, std::error_code>'
21
Returned allocated memory
22
Calling constructor for 'Error'
333}
334
335/// Base class for user error types. Users should declare their error types
336/// like:
337///
338/// class MyError : public ErrorInfo<MyError> {
339/// ....
340/// };
341///
342/// This class provides an implementation of the ErrorInfoBase::kind
343/// method, which is used by the Error RTTI system.
344template <typename ThisErrT, typename ParentErrT = ErrorInfoBase>
345class ErrorInfo : public ParentErrT {
346public:
347 using ParentErrT::ParentErrT; // inherit constructors
348
349 static const void *classID() { return &ThisErrT::ID; }
350
351 const void *dynamicClassID() const override { return &ThisErrT::ID; }
352
353 bool isA(const void *const ClassID) const override {
354 return ClassID == classID() || ParentErrT::isA(ClassID);
355 }
356};
357
358/// Special ErrorInfo subclass representing a list of ErrorInfos.
359/// Instances of this class are constructed by joinError.
360class ErrorList final : public ErrorInfo<ErrorList> {
361 // handleErrors needs to be able to iterate the payload list of an
362 // ErrorList.
363 template <typename... HandlerTs>
364 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
365
366 // joinErrors is implemented in terms of join.
367 friend Error joinErrors(Error, Error);
368
369public:
370 void log(raw_ostream &OS) const override {
371 OS << "Multiple errors:\n";
372 for (auto &ErrPayload : Payloads) {
373 ErrPayload->log(OS);
374 OS << "\n";
375 }
376 }
377
378 std::error_code convertToErrorCode() const override;
379
380 // Used by ErrorInfo::classID.
381 static char ID;
382
383private:
384 ErrorList(std::unique_ptr<ErrorInfoBase> Payload1,
385 std::unique_ptr<ErrorInfoBase> Payload2) {
386 assert(!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() &&((!Payload1->isA<ErrorList>() && !Payload2->
isA<ErrorList>() && "ErrorList constructor payloads should be singleton errors"
) ? static_cast<void> (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 387, __PRETTY_FUNCTION__))
387 "ErrorList constructor payloads should be singleton errors")((!Payload1->isA<ErrorList>() && !Payload2->
isA<ErrorList>() && "ErrorList constructor payloads should be singleton errors"
) ? static_cast<void> (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 387, __PRETTY_FUNCTION__))
;
388 Payloads.push_back(std::move(Payload1));
389 Payloads.push_back(std::move(Payload2));
390 }
391
392 static Error join(Error E1, Error E2) {
393 if (!E1)
394 return E2;
395 if (!E2)
396 return E1;
397 if (E1.isA<ErrorList>()) {
398 auto &E1List = static_cast<ErrorList &>(*E1.getPtr());
399 if (E2.isA<ErrorList>()) {
400 auto E2Payload = E2.takePayload();
401 auto &E2List = static_cast<ErrorList &>(*E2Payload);
402 for (auto &Payload : E2List.Payloads)
403 E1List.Payloads.push_back(std::move(Payload));
404 } else
405 E1List.Payloads.push_back(E2.takePayload());
406
407 return E1;
408 }
409 if (E2.isA<ErrorList>()) {
410 auto &E2List = static_cast<ErrorList &>(*E2.getPtr());
411 E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload());
412 return E2;
413 }
414 return Error(std::unique_ptr<ErrorList>(
415 new ErrorList(E1.takePayload(), E2.takePayload())));
416 }
417
418 std::vector<std::unique_ptr<ErrorInfoBase>> Payloads;
419};
420
421/// Concatenate errors. The resulting Error is unchecked, and contains the
422/// ErrorInfo(s), if any, contained in E1, followed by the
423/// ErrorInfo(s), if any, contained in E2.
424inline Error joinErrors(Error E1, Error E2) {
425 return ErrorList::join(std::move(E1), std::move(E2));
426}
427
428/// Tagged union holding either a T or a Error.
429///
430/// This class parallels ErrorOr, but replaces error_code with Error. Since
431/// Error cannot be copied, this class replaces getError() with
432/// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the
433/// error class type.
434template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected {
435 template <class T1> friend class ExpectedAsOutParameter;
436 template <class OtherT> friend class Expected;
437
438 static const bool isRef = std::is_reference<T>::value;
439
440 using wrap = std::reference_wrapper<typename std::remove_reference<T>::type>;
441
442 using error_type = std::unique_ptr<ErrorInfoBase>;
443
444public:
445 using storage_type = typename std::conditional<isRef, wrap, T>::type;
446 using value_type = T;
447
448private:
449 using reference = typename std::remove_reference<T>::type &;
450 using const_reference = const typename std::remove_reference<T>::type &;
451 using pointer = typename std::remove_reference<T>::type *;
452 using const_pointer = const typename std::remove_reference<T>::type *;
453
454public:
455 /// Create an Expected<T> error value from the given Error.
456 Expected(Error Err)
457 : HasError(true)
458#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
459 // Expected is unchecked upon construction in Debug builds.
460 , Unchecked(true)
461#endif
462 {
463 assert(Err && "Cannot create Expected<T> from Error success value.")((Err && "Cannot create Expected<T> from Error success value."
) ? static_cast<void> (0) : __assert_fail ("Err && \"Cannot create Expected<T> from Error success value.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 463, __PRETTY_FUNCTION__))
;
464 new (getErrorStorage()) error_type(Err.takePayload());
465 }
466
467 /// Forbid to convert from Error::success() implicitly, this avoids having
468 /// Expected<T> foo() { return Error::success(); } which compiles otherwise
469 /// but triggers the assertion above.
470 Expected(ErrorSuccess) = delete;
471
472 /// Create an Expected<T> success value from the given OtherT value, which
473 /// must be convertible to T.
474 template <typename OtherT>
475 Expected(OtherT &&Val,
476 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
477 * = nullptr)
478 : HasError(false)
479#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
480 // Expected is unchecked upon construction in Debug builds.
481 , Unchecked(true)
482#endif
483 {
484 new (getStorage()) storage_type(std::forward<OtherT>(Val));
485 }
486
487 /// Move construct an Expected<T> value.
488 Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
489
490 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
491 /// must be convertible to T.
492 template <class OtherT>
493 Expected(Expected<OtherT> &&Other,
494 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
495 * = nullptr) {
496 moveConstruct(std::move(Other));
497 }
498
499 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
500 /// isn't convertible to T.
501 template <class OtherT>
502 explicit Expected(
503 Expected<OtherT> &&Other,
504 typename std::enable_if<!std::is_convertible<OtherT, T>::value>::type * =
505 nullptr) {
506 moveConstruct(std::move(Other));
507 }
508
509 /// Move-assign from another Expected<T>.
510 Expected &operator=(Expected &&Other) {
511 moveAssign(std::move(Other));
512 return *this;
513 }
514
515 /// Destroy an Expected<T>.
516 ~Expected() {
517 assertIsChecked();
518 if (!HasError)
519 getStorage()->~storage_type();
520 else
521 getErrorStorage()->~error_type();
522 }
523
524 /// Return false if there is an error.
525 explicit operator bool() {
526#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
527 Unchecked = HasError;
528#endif
529 return !HasError;
530 }
531
532 /// Returns a reference to the stored T value.
533 reference get() {
534 assertIsChecked();
535 return *getStorage();
536 }
537
538 /// Returns a const reference to the stored T value.
539 const_reference get() const {
540 assertIsChecked();
541 return const_cast<Expected<T> *>(this)->get();
542 }
543
544 /// Check that this Expected<T> is an error of type ErrT.
545 template <typename ErrT> bool errorIsA() const {
546 return HasError && (*getErrorStorage())->template isA<ErrT>();
547 }
548
549 /// Take ownership of the stored error.
550 /// After calling this the Expected<T> is in an indeterminate state that can
551 /// only be safely destructed. No further calls (beside the destructor) should
552 /// be made on the Expected<T> vaule.
553 Error takeError() {
554#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
555 Unchecked = false;
556#endif
557 return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
558 }
559
560 /// Returns a pointer to the stored T value.
561 pointer operator->() {
562 assertIsChecked();
563 return toPointer(getStorage());
564 }
565
566 /// Returns a const pointer to the stored T value.
567 const_pointer operator->() const {
568 assertIsChecked();
569 return toPointer(getStorage());
570 }
571
572 /// Returns a reference to the stored T value.
573 reference operator*() {
574 assertIsChecked();
575 return *getStorage();
576 }
577
578 /// Returns a const reference to the stored T value.
579 const_reference operator*() const {
580 assertIsChecked();
581 return *getStorage();
582 }
583
584private:
585 template <class T1>
586 static bool compareThisIfSameType(const T1 &a, const T1 &b) {
587 return &a == &b;
588 }
589
590 template <class T1, class T2>
591 static bool compareThisIfSameType(const T1 &a, const T2 &b) {
592 return false;
593 }
594
595 template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) {
596 HasError = Other.HasError;
597#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
598 Unchecked = true;
599 Other.Unchecked = false;
600#endif
601
602 if (!HasError)
603 new (getStorage()) storage_type(std::move(*Other.getStorage()));
604 else
605 new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage()));
606 }
607
608 template <class OtherT> void moveAssign(Expected<OtherT> &&Other) {
609 assertIsChecked();
610
611 if (compareThisIfSameType(*this, Other))
612 return;
613
614 this->~Expected();
615 new (this) Expected(std::move(Other));
616 }
617
618 pointer toPointer(pointer Val) { return Val; }
619
620 const_pointer toPointer(const_pointer Val) const { return Val; }
621
622 pointer toPointer(wrap *Val) { return &Val->get(); }
623
624 const_pointer toPointer(const wrap *Val) const { return &Val->get(); }
625
626 storage_type *getStorage() {
627 assert(!HasError && "Cannot get value when an error exists!")((!HasError && "Cannot get value when an error exists!"
) ? static_cast<void> (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 627, __PRETTY_FUNCTION__))
;
628 return reinterpret_cast<storage_type *>(TStorage.buffer);
629 }
630
631 const storage_type *getStorage() const {
632 assert(!HasError && "Cannot get value when an error exists!")((!HasError && "Cannot get value when an error exists!"
) ? static_cast<void> (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 632, __PRETTY_FUNCTION__))
;
633 return reinterpret_cast<const storage_type *>(TStorage.buffer);
634 }
635
636 error_type *getErrorStorage() {
637 assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!"
) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 637, __PRETTY_FUNCTION__))
;
638 return reinterpret_cast<error_type *>(ErrorStorage.buffer);
639 }
640
641 const error_type *getErrorStorage() const {
642 assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!"
) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 642, __PRETTY_FUNCTION__))
;
643 return reinterpret_cast<const error_type *>(ErrorStorage.buffer);
644 }
645
646 // Used by ExpectedAsOutParameter to reset the checked flag.
647 void setUnchecked() {
648#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
649 Unchecked = true;
650#endif
651 }
652
653#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
654 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
655 LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline))
656 void fatalUncheckedExpected() const {
657 dbgs() << "Expected<T> must be checked before access or destruction.\n";
658 if (HasError) {
659 dbgs() << "Unchecked Expected<T> contained error:\n";
660 (*getErrorStorage())->log(dbgs());
661 } else
662 dbgs() << "Expected<T> value was in success state. (Note: Expected<T> "
663 "values in success mode must still be checked prior to being "
664 "destroyed).\n";
665 abort();
666 }
667#endif
668
669 void assertIsChecked() {
670#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
671 if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false))
672 fatalUncheckedExpected();
673#endif
674 }
675
676 union {
677 AlignedCharArrayUnion<storage_type> TStorage;
678 AlignedCharArrayUnion<error_type> ErrorStorage;
679 };
680 bool HasError : 1;
681#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
682 bool Unchecked : 1;
683#endif
684};
685
686/// Report a serious error, calling any installed error handler. See
687/// ErrorHandling.h.
688LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) void report_fatal_error(Error Err,
689 bool gen_crash_diag = true);
690
691/// Report a fatal error if Err is a failure value.
692///
693/// This function can be used to wrap calls to fallible functions ONLY when it
694/// is known that the Error will always be a success value. E.g.
695///
696/// @code{.cpp}
697/// // foo only attempts the fallible operation if DoFallibleOperation is
698/// // true. If DoFallibleOperation is false then foo always returns
699/// // Error::success().
700/// Error foo(bool DoFallibleOperation);
701///
702/// cantFail(foo(false));
703/// @endcode
704inline void cantFail(Error Err, const char *Msg = nullptr) {
705 if (Err) {
706 if (!Msg)
707 Msg = "Failure value returned from cantFail wrapped call";
708 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 708)
;
709 }
710}
711
712/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
713/// returns the contained value.
714///
715/// This function can be used to wrap calls to fallible functions ONLY when it
716/// is known that the Error will always be a success value. E.g.
717///
718/// @code{.cpp}
719/// // foo only attempts the fallible operation if DoFallibleOperation is
720/// // true. If DoFallibleOperation is false then foo always returns an int.
721/// Expected<int> foo(bool DoFallibleOperation);
722///
723/// int X = cantFail(foo(false));
724/// @endcode
725template <typename T>
726T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) {
727 if (ValOrErr)
728 return std::move(*ValOrErr);
729 else {
730 if (!Msg)
731 Msg = "Failure value returned from cantFail wrapped call";
732 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 732)
;
733 }
734}
735
736/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
737/// returns the contained reference.
738///
739/// This function can be used to wrap calls to fallible functions ONLY when it
740/// is known that the Error will always be a success value. E.g.
741///
742/// @code{.cpp}
743/// // foo only attempts the fallible operation if DoFallibleOperation is
744/// // true. If DoFallibleOperation is false then foo always returns a Bar&.
745/// Expected<Bar&> foo(bool DoFallibleOperation);
746///
747/// Bar &X = cantFail(foo(false));
748/// @endcode
749template <typename T>
750T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) {
751 if (ValOrErr)
752 return *ValOrErr;
753 else {
754 if (!Msg)
755 Msg = "Failure value returned from cantFail wrapped call";
756 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 756)
;
757 }
758}
759
760/// Helper for testing applicability of, and applying, handlers for
761/// ErrorInfo types.
762template <typename HandlerT>
763class ErrorHandlerTraits
764 : public ErrorHandlerTraits<decltype(
765 &std::remove_reference<HandlerT>::type::operator())> {};
766
767// Specialization functions of the form 'Error (const ErrT&)'.
768template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> {
769public:
770 static bool appliesTo(const ErrorInfoBase &E) {
771 return E.template isA<ErrT>();
772 }
773
774 template <typename HandlerT>
775 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
776 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 776, __PRETTY_FUNCTION__))
;
777 return H(static_cast<ErrT &>(*E));
778 }
779};
780
781// Specialization functions of the form 'void (const ErrT&)'.
782template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> {
783public:
784 static bool appliesTo(const ErrorInfoBase &E) {
785 return E.template isA<ErrT>();
786 }
787
788 template <typename HandlerT>
789 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
790 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 790, __PRETTY_FUNCTION__))
;
791 H(static_cast<ErrT &>(*E));
792 return Error::success();
793 }
794};
795
796/// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'.
797template <typename ErrT>
798class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> {
799public:
800 static bool appliesTo(const ErrorInfoBase &E) {
801 return E.template isA<ErrT>();
802 }
803
804 template <typename HandlerT>
805 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
806 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 806, __PRETTY_FUNCTION__))
;
807 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
808 return H(std::move(SubE));
809 }
810};
811
812/// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'.
813template <typename ErrT>
814class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> {
815public:
816 static bool appliesTo(const ErrorInfoBase &E) {
817 return E.template isA<ErrT>();
818 }
819
820 template <typename HandlerT>
821 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
822 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 822, __PRETTY_FUNCTION__))
;
823 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
824 H(std::move(SubE));
825 return Error::success();
826 }
827};
828
829// Specialization for member functions of the form 'RetT (const ErrT&)'.
830template <typename C, typename RetT, typename ErrT>
831class ErrorHandlerTraits<RetT (C::*)(ErrT &)>
832 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
833
834// Specialization for member functions of the form 'RetT (const ErrT&) const'.
835template <typename C, typename RetT, typename ErrT>
836class ErrorHandlerTraits<RetT (C::*)(ErrT &) const>
837 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
838
839// Specialization for member functions of the form 'RetT (const ErrT&)'.
840template <typename C, typename RetT, typename ErrT>
841class ErrorHandlerTraits<RetT (C::*)(const ErrT &)>
842 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
843
844// Specialization for member functions of the form 'RetT (const ErrT&) const'.
845template <typename C, typename RetT, typename ErrT>
846class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const>
847 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
848
849/// Specialization for member functions of the form
850/// 'RetT (std::unique_ptr<ErrT>)'.
851template <typename C, typename RetT, typename ErrT>
852class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)>
853 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
854
855/// Specialization for member functions of the form
856/// 'RetT (std::unique_ptr<ErrT>) const'.
857template <typename C, typename RetT, typename ErrT>
858class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const>
859 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
860
861inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) {
862 return Error(std::move(Payload));
863}
864
865template <typename HandlerT, typename... HandlerTs>
866Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload,
867 HandlerT &&Handler, HandlerTs &&... Handlers) {
868 if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload))
869 return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler),
870 std::move(Payload));
871 return handleErrorImpl(std::move(Payload),
872 std::forward<HandlerTs>(Handlers)...);
873}
874
875/// Pass the ErrorInfo(s) contained in E to their respective handlers. Any
876/// unhandled errors (or Errors returned by handlers) are re-concatenated and
877/// returned.
878/// Because this function returns an error, its result must also be checked
879/// or returned. If you intend to handle all errors use handleAllErrors
880/// (which returns void, and will abort() on unhandled errors) instead.
881template <typename... HandlerTs>
882Error handleErrors(Error E, HandlerTs &&... Hs) {
883 if (!E)
884 return Error::success();
885
886 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
887
888 if (Payload->isA<ErrorList>()) {
889 ErrorList &List = static_cast<ErrorList &>(*Payload);
890 Error R;
891 for (auto &P : List.Payloads)
892 R = ErrorList::join(
893 std::move(R),
894 handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...));
895 return R;
896 }
897
898 return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...);
899}
900
901/// Behaves the same as handleErrors, except that by contract all errors
902/// *must* be handled by the given handlers (i.e. there must be no remaining
903/// errors after running the handlers, or llvm_unreachable is called).
904template <typename... HandlerTs>
905void handleAllErrors(Error E, HandlerTs &&... Handlers) {
906 cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
907}
908
909/// Check that E is a non-error, then drop it.
910/// If E is an error, llvm_unreachable will be called.
911inline void handleAllErrors(Error E) {
912 cantFail(std::move(E));
913}
914
915/// Handle any errors (if present) in an Expected<T>, then try a recovery path.
916///
917/// If the incoming value is a success value it is returned unmodified. If it
918/// is a failure value then it the contained error is passed to handleErrors.
919/// If handleErrors is able to handle the error then the RecoveryPath functor
920/// is called to supply the final result. If handleErrors is not able to
921/// handle all errors then the unhandled errors are returned.
922///
923/// This utility enables the follow pattern:
924///
925/// @code{.cpp}
926/// enum FooStrategy { Aggressive, Conservative };
927/// Expected<Foo> foo(FooStrategy S);
928///
929/// auto ResultOrErr =
930/// handleExpected(
931/// foo(Aggressive),
932/// []() { return foo(Conservative); },
933/// [](AggressiveStrategyError&) {
934/// // Implicitly conusme this - we'll recover by using a conservative
935/// // strategy.
936/// });
937///
938/// @endcode
939template <typename T, typename RecoveryFtor, typename... HandlerTs>
940Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath,
941 HandlerTs &&... Handlers) {
942 if (ValOrErr)
943 return ValOrErr;
944
945 if (auto Err = handleErrors(ValOrErr.takeError(),
946 std::forward<HandlerTs>(Handlers)...))
947 return std::move(Err);
948
949 return RecoveryPath();
950}
951
952/// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner
953/// will be printed before the first one is logged. A newline will be printed
954/// after each error.
955///
956/// This is useful in the base level of your program to allow clean termination
957/// (allowing clean deallocation of resources, etc.), while reporting error
958/// information to the user.
959void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner);
960
961/// Write all error messages (if any) in E to a string. The newline character
962/// is used to separate error messages.
963inline std::string toString(Error E) {
964 SmallVector<std::string, 2> Errors;
965 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
966 Errors.push_back(EI.message());
967 });
968 return join(Errors.begin(), Errors.end(), "\n");
969}
970
971/// Consume a Error without doing anything. This method should be used
972/// only where an error can be considered a reasonable and expected return
973/// value.
974///
975/// Uses of this method are potentially indicative of design problems: If it's
976/// legitimate to do nothing while processing an "error", the error-producer
977/// might be more clearly refactored to return an Optional<T>.
978inline void consumeError(Error Err) {
979 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
980}
981
982/// Helper for converting an Error to a bool.
983///
984/// This method returns true if Err is in an error state, or false if it is
985/// in a success state. Puts Err in a checked state in both cases (unlike
986/// Error::operator bool(), which only does this for success states).
987inline bool errorToBool(Error Err) {
988 bool IsError = static_cast<bool>(Err);
989 if (IsError)
990 consumeError(std::move(Err));
991 return IsError;
992}
993
994/// Helper for Errors used as out-parameters.
995///
996/// This helper is for use with the Error-as-out-parameter idiom, where an error
997/// is passed to a function or method by reference, rather than being returned.
998/// In such cases it is helpful to set the checked bit on entry to the function
999/// so that the error can be written to (unchecked Errors abort on assignment)
1000/// and clear the checked bit on exit so that clients cannot accidentally forget
1001/// to check the result. This helper performs these actions automatically using
1002/// RAII:
1003///
1004/// @code{.cpp}
1005/// Result foo(Error &Err) {
1006/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1007/// // <body of foo>
1008/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1009/// }
1010/// @endcode
1011///
1012/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1013/// used with optional Errors (Error pointers that are allowed to be null). If
1014/// ErrorAsOutParameter took an Error reference, an instance would have to be
1015/// created inside every condition that verified that Error was non-null. By
1016/// taking an Error pointer we can just create one instance at the top of the
1017/// function.
1018class ErrorAsOutParameter {
1019public:
1020 ErrorAsOutParameter(Error *Err) : Err(Err) {
1021 // Raise the checked bit if Err is success.
1022 if (Err)
1023 (void)!!*Err;
1024 }
1025
1026 ~ErrorAsOutParameter() {
1027 // Clear the checked bit.
1028 if (Err && !*Err)
1029 *Err = Error::success();
1030 }
1031
1032private:
1033 Error *Err;
1034};
1035
1036/// Helper for Expected<T>s used as out-parameters.
1037///
1038/// See ErrorAsOutParameter.
1039template <typename T>
1040class ExpectedAsOutParameter {
1041public:
1042 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1043 : ValOrErr(ValOrErr) {
1044 if (ValOrErr)
1045 (void)!!*ValOrErr;
1046 }
1047
1048 ~ExpectedAsOutParameter() {
1049 if (ValOrErr)
1050 ValOrErr->setUnchecked();
1051 }
1052
1053private:
1054 Expected<T> *ValOrErr;
1055};
1056
1057/// This class wraps a std::error_code in a Error.
1058///
1059/// This is useful if you're writing an interface that returns a Error
1060/// (or Expected) and you want to call code that still returns
1061/// std::error_codes.
1062class ECError : public ErrorInfo<ECError> {
1063 friend Error errorCodeToError(std::error_code);
1064
1065public:
1066 void setErrorCode(std::error_code EC) { this->EC = EC; }
1067 std::error_code convertToErrorCode() const override { return EC; }
1068 void log(raw_ostream &OS) const override { OS << EC.message(); }
1069
1070 // Used by ErrorInfo::classID.
1071 static char ID;
1072
1073protected:
1074 ECError() = default;
1075 ECError(std::error_code EC) : EC(EC) {}
1076
1077 std::error_code EC;
1078};
1079
1080/// The value returned by this function can be returned from convertToErrorCode
1081/// for Error values where no sensible translation to std::error_code exists.
1082/// It should only be used in this situation, and should never be used where a
1083/// sensible conversion to std::error_code is available, as attempts to convert
1084/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1085///error to try to convert such a value).
1086std::error_code inconvertibleErrorCode();
1087
1088/// Helper for converting an std::error_code to a Error.
1089Error errorCodeToError(std::error_code EC);
1090
1091/// Helper for converting an ECError to a std::error_code.
1092///
1093/// This method requires that Err be Error() or an ECError, otherwise it
1094/// will trigger a call to abort().
1095std::error_code errorToErrorCode(Error Err);
1096
1097/// Convert an ErrorOr<T> to an Expected<T>.
1098template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1099 if (auto EC = EO.getError())
1100 return errorCodeToError(EC);
1101 return std::move(*EO);
1102}
1103
1104/// Convert an Expected<T> to an ErrorOr<T>.
1105template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1106 if (auto Err = E.takeError())
1107 return errorToErrorCode(std::move(Err));
1108 return std::move(*E);
1109}
1110
1111/// This class wraps a string in an Error.
1112///
1113/// StringError is useful in cases where the client is not expected to be able
1114/// to consume the specific error message programmatically (for example, if the
1115/// error message is to be presented to the user).
1116///
1117/// StringError can also be used when additional information is to be printed
1118/// along with a error_code message. Depending on the constructor called, this
1119/// class can either display:
1120/// 1. the error_code message (ECError behavior)
1121/// 2. a string
1122/// 3. the error_code message and a string
1123///
1124/// These behaviors are useful when subtyping is required; for example, when a
1125/// specific library needs an explicit error type. In the example below,
1126/// PDBError is derived from StringError:
1127///
1128/// @code{.cpp}
1129/// Expected<int> foo() {
1130/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1131/// "Additional information");
1132/// }
1133/// @endcode
1134///
1135class StringError : public ErrorInfo<StringError> {
1136public:
1137 static char ID;
1138
1139 // Prints EC + S and converts to EC
1140 StringError(std::error_code EC, const Twine &S = Twine());
1141
1142 // Prints S and converts to EC
1143 StringError(const Twine &S, std::error_code EC);
1144
1145 void log(raw_ostream &OS) const override;
1146 std::error_code convertToErrorCode() const override;
1147
1148 const std::string &getMessage() const { return Msg; }
1149
1150private:
1151 std::string Msg;
1152 std::error_code EC;
1153 const bool PrintMsgOnly = false;
1154};
1155
1156/// Create formatted StringError object.
1157template <typename... Ts>
1158Error createStringError(std::error_code EC, char const *Fmt,
1159 const Ts &... Vals) {
1160 std::string Buffer;
1161 raw_string_ostream Stream(Buffer);
1162 Stream << format(Fmt, Vals...);
1163 return make_error<StringError>(Stream.str(), EC);
1164}
1165
1166Error createStringError(std::error_code EC, char const *Msg);
1167
1168/// This class wraps a filename and another Error.
1169///
1170/// In some cases, an error needs to live along a 'source' name, in order to
1171/// show more detailed information to the user.
1172class FileError final : public ErrorInfo<FileError> {
1173
1174 friend Error createFileError(std::string, Error);
1175
1176public:
1177 void log(raw_ostream &OS) const override {
1178 assert(Err && !FileName.empty() && "Trying to log after takeError().")((Err && !FileName.empty() && "Trying to log after takeError()."
) ? static_cast<void> (0) : __assert_fail ("Err && !FileName.empty() && \"Trying to log after takeError().\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1178, __PRETTY_FUNCTION__))
;
1179 OS << "'" << FileName << "': ";
1180 Err->log(OS);
1181 }
1182
1183 Error takeError() { return Error(std::move(Err)); }
1184
1185 std::error_code convertToErrorCode() const override;
1186
1187 // Used by ErrorInfo::classID.
1188 static char ID;
1189
1190private:
1191 FileError(std::string F, std::unique_ptr<ErrorInfoBase> E) {
1192 assert(E && "Cannot create FileError from Error success value.")((E && "Cannot create FileError from Error success value."
) ? static_cast<void> (0) : __assert_fail ("E && \"Cannot create FileError from Error success value.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1192, __PRETTY_FUNCTION__))
;
1193 assert(!F.empty() &&((!F.empty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.empty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1194, __PRETTY_FUNCTION__))
1194 "The file name provided to FileError must not be empty.")((!F.empty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.empty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/Support/Error.h"
, 1194, __PRETTY_FUNCTION__))
;
1195 FileName = F;
1196 Err = std::move(E);
1197 }
1198
1199 static Error build(std::string F, Error E) {
1200 return Error(std::unique_ptr<FileError>(new FileError(F, E.takePayload())));
1201 }
1202
1203 std::string FileName;
1204 std::unique_ptr<ErrorInfoBase> Err;
1205};
1206
1207/// Concatenate a source file path and/or name with an Error. The resulting
1208/// Error is unchecked.
1209inline Error createFileError(std::string F, Error E) {
1210 return FileError::build(F, std::move(E));
1211}
1212
1213Error createFileError(std::string F, ErrorSuccess) = delete;
1214
1215/// Helper for check-and-exit error handling.
1216///
1217/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1218///
1219class ExitOnError {
1220public:
1221 /// Create an error on exit helper.
1222 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1223 : Banner(std::move(Banner)),
1224 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1225
1226 /// Set the banner string for any errors caught by operator().
1227 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1228
1229 /// Set the exit-code mapper function.
1230 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1231 this->GetExitCode = std::move(GetExitCode);
1232 }
1233
1234 /// Check Err. If it's in a failure state log the error(s) and exit.
1235 void operator()(Error Err) const { checkError(std::move(Err)); }
1236
1237 /// Check E. If it's in a success state then return the contained value. If
1238 /// it's in a failure state log the error(s) and exit.
1239 template <typename T> T operator()(Expected<T> &&E) const {
1240 checkError(E.takeError());
1241 return std::move(*E);
1242 }
1243
1244 /// Check E. If it's in a success state then return the contained reference. If
1245 /// it's in a failure state log the error(s) and exit.
1246 template <typename T> T& operator()(Expected<T&> &&E) const {
1247 checkError(E.takeError());
1248 return *E;
1249 }
1250
1251private:
1252 void checkError(Error Err) const {
1253 if (Err) {
1254 int ExitCode = GetExitCode(Err);
1255 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1256 exit(ExitCode);
1257 }
1258 }
1259
1260 std::string Banner;
1261 std::function<int(const Error &)> GetExitCode;
1262};
1263
1264/// Conversion from Error to LLVMErrorRef for C error bindings.
1265inline LLVMErrorRef wrap(Error Err) {
1266 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1267}
1268
1269/// Conversion from LLVMErrorRef to Error for C error bindings.
1270inline Error unwrap(LLVMErrorRef ErrRef) {
1271 return Error(std::unique_ptr<ErrorInfoBase>(
1272 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1273}
1274
1275} // end namespace llvm
1276
1277#endif // LLVM_SUPPORT_ERROR_H

/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h

1//===- llvm/ADT/STLExtras.h - Useful STL related functions ------*- C++ -*-===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file contains some templates that are useful if you are working with the
11// STL at all.
12//
13// No library is required when using these functions.
14//
15//===----------------------------------------------------------------------===//
16
17#ifndef LLVM_ADT_STLEXTRAS_H
18#define LLVM_ADT_STLEXTRAS_H
19
20#include "llvm/ADT/Optional.h"
21#include "llvm/ADT/SmallVector.h"
22#include "llvm/ADT/iterator.h"
23#include "llvm/ADT/iterator_range.h"
24#include "llvm/Config/abi-breaking.h"
25#include "llvm/Support/ErrorHandling.h"
26#include <algorithm>
27#include <cassert>
28#include <cstddef>
29#include <cstdint>
30#include <cstdlib>
31#include <functional>
32#include <initializer_list>
33#include <iterator>
34#include <limits>
35#include <memory>
36#include <tuple>
37#include <type_traits>
38#include <utility>
39
40#ifdef EXPENSIVE_CHECKS
41#include <random> // for std::mt19937
42#endif
43
44namespace llvm {
45
46// Only used by compiler if both template types are the same. Useful when
47// using SFINAE to test for the existence of member functions.
48template <typename T, T> struct SameType;
49
50namespace detail {
51
52template <typename RangeT>
53using IterOfRange = decltype(std::begin(std::declval<RangeT &>()));
54
55template <typename RangeT>
56using ValueOfRange = typename std::remove_reference<decltype(
57 *std::begin(std::declval<RangeT &>()))>::type;
58
59} // end namespace detail
60
61//===----------------------------------------------------------------------===//
62// Extra additions to <type_traits>
63//===----------------------------------------------------------------------===//
64
65template <typename T>
66struct negation : std::integral_constant<bool, !bool(T::value)> {};
67
68template <typename...> struct conjunction : std::true_type {};
69template <typename B1> struct conjunction<B1> : B1 {};
70template <typename B1, typename... Bn>
71struct conjunction<B1, Bn...>
72 : std::conditional<bool(B1::value), conjunction<Bn...>, B1>::type {};
73
74//===----------------------------------------------------------------------===//
75// Extra additions to <functional>
76//===----------------------------------------------------------------------===//
77
78template <class Ty> struct identity {
79 using argument_type = Ty;
80
81 Ty &operator()(Ty &self) const {
82 return self;
83 }
84 const Ty &operator()(const Ty &self) const {
85 return self;
86 }
87};
88
89template <class Ty> struct less_ptr {
90 bool operator()(const Ty* left, const Ty* right) const {
91 return *left < *right;
92 }
93};
94
95template <class Ty> struct greater_ptr {
96 bool operator()(const Ty* left, const Ty* right) const {
97 return *right < *left;
98 }
99};
100
101/// An efficient, type-erasing, non-owning reference to a callable. This is
102/// intended for use as the type of a function parameter that is not used
103/// after the function in question returns.
104///
105/// This class does not own the callable, so it is not in general safe to store
106/// a function_ref.
107template<typename Fn> class function_ref;
108
109template<typename Ret, typename ...Params>
110class function_ref<Ret(Params...)> {
111 Ret (*callback)(intptr_t callable, Params ...params) = nullptr;
112 intptr_t callable;
113
114 template<typename Callable>
115 static Ret callback_fn(intptr_t callable, Params ...params) {
116 return (*reinterpret_cast<Callable*>(callable))(
117 std::forward<Params>(params)...);
118 }
119
120public:
121 function_ref() = default;
122 function_ref(std::nullptr_t) {}
123
124 template <typename Callable>
125 function_ref(Callable &&callable,
126 typename std::enable_if<
127 !std::is_same<typename std::remove_reference<Callable>::type,
128 function_ref>::value>::type * = nullptr)
129 : callback(callback_fn<typename std::remove_reference<Callable>::type>),
130 callable(reinterpret_cast<intptr_t>(&callable)) {}
131
132 Ret operator()(Params ...params) const {
133 return callback(callable, std::forward<Params>(params)...);
134 }
135
136 operator bool() const { return callback; }
137};
138
139// deleter - Very very very simple method that is used to invoke operator
140// delete on something. It is used like this:
141//
142// for_each(V.begin(), B.end(), deleter<Interval>);
143template <class T>
144inline void deleter(T *Ptr) {
145 delete Ptr;
146}
147
148//===----------------------------------------------------------------------===//
149// Extra additions to <iterator>
150//===----------------------------------------------------------------------===//
151
152namespace adl_detail {
153
154using std::begin;
155
156template <typename ContainerTy>
157auto adl_begin(ContainerTy &&container)
158 -> decltype(begin(std::forward<ContainerTy>(container))) {
159 return begin(std::forward<ContainerTy>(container));
160}
161
162using std::end;
163
164template <typename ContainerTy>
165auto adl_end(ContainerTy &&container)
166 -> decltype(end(std::forward<ContainerTy>(container))) {
167 return end(std::forward<ContainerTy>(container));
168}
169
170using std::swap;
171
172template <typename T>
173void adl_swap(T &&lhs, T &&rhs) noexcept(noexcept(swap(std::declval<T>(),
174 std::declval<T>()))) {
175 swap(std::forward<T>(lhs), std::forward<T>(rhs));
176}
177
178} // end namespace adl_detail
179
180template <typename ContainerTy>
181auto adl_begin(ContainerTy &&container)
182 -> decltype(adl_detail::adl_begin(std::forward<ContainerTy>(container))) {
183 return adl_detail::adl_begin(std::forward<ContainerTy>(container));
184}
185
186template <typename ContainerTy>
187auto adl_end(ContainerTy &&container)
188 -> decltype(adl_detail::adl_end(std::forward<ContainerTy>(container))) {
189 return adl_detail::adl_end(std::forward<ContainerTy>(container));
190}
191
192template <typename T>
193void adl_swap(T &&lhs, T &&rhs) noexcept(
194 noexcept(adl_detail::adl_swap(std::declval<T>(), std::declval<T>()))) {
195 adl_detail::adl_swap(std::forward<T>(lhs), std::forward<T>(rhs));
196}
197
198// mapped_iterator - This is a simple iterator adapter that causes a function to
199// be applied whenever operator* is invoked on the iterator.
200
201template <typename ItTy, typename FuncTy,
202 typename FuncReturnTy =
203 decltype(std::declval<FuncTy>()(*std::declval<ItTy>()))>
204class mapped_iterator
205 : public iterator_adaptor_base<
206 mapped_iterator<ItTy, FuncTy>, ItTy,
207 typename std::iterator_traits<ItTy>::iterator_category,
208 typename std::remove_reference<FuncReturnTy>::type> {
209public:
210 mapped_iterator(ItTy U, FuncTy F)
211 : mapped_iterator::iterator_adaptor_base(std::move(U)), F(std::move(F)) {}
212
213 ItTy getCurrent() { return this->I; }
214
215 FuncReturnTy operator*() { return F(*this->I); }
216
217private:
218 FuncTy F;
219};
220
221// map_iterator - Provide a convenient way to create mapped_iterators, just like
222// make_pair is useful for creating pairs...
223template <class ItTy, class FuncTy>
224inline mapped_iterator<ItTy, FuncTy> map_iterator(ItTy I, FuncTy F) {
225 return mapped_iterator<ItTy, FuncTy>(std::move(I), std::move(F));
226}
227
228/// Helper to determine if type T has a member called rbegin().
229template <typename Ty> class has_rbegin_impl {
230 using yes = char[1];
231 using no = char[2];
232
233 template <typename Inner>
234 static yes& test(Inner *I, decltype(I->rbegin()) * = nullptr);
235
236 template <typename>
237 static no& test(...);
238
239public:
240 static const bool value = sizeof(test<Ty>(nullptr)) == sizeof(yes);
241};
242
243/// Metafunction to determine if T& or T has a member called rbegin().
244template <typename Ty>
245struct has_rbegin : has_rbegin_impl<typename std::remove_reference<Ty>::type> {
246};
247
248// Returns an iterator_range over the given container which iterates in reverse.
249// Note that the container must have rbegin()/rend() methods for this to work.
250template <typename ContainerTy>
251auto reverse(ContainerTy &&C,
252 typename std::enable_if<has_rbegin<ContainerTy>::value>::type * =
253 nullptr) -> decltype(make_range(C.rbegin(), C.rend())) {
254 return make_range(C.rbegin(), C.rend());
255}
256
257// Returns a std::reverse_iterator wrapped around the given iterator.
258template <typename IteratorTy>
259std::reverse_iterator<IteratorTy> make_reverse_iterator(IteratorTy It) {
260 return std::reverse_iterator<IteratorTy>(It);
261}
262
263// Returns an iterator_range over the given container which iterates in reverse.
264// Note that the container must have begin()/end() methods which return
265// bidirectional iterators for this to work.
266template <typename ContainerTy>
267auto reverse(
268 ContainerTy &&C,
269 typename std::enable_if<!has_rbegin<ContainerTy>::value>::type * = nullptr)
270 -> decltype(make_range(llvm::make_reverse_iterator(std::end(C)),
271 llvm::make_reverse_iterator(std::begin(C)))) {
272 return make_range(llvm::make_reverse_iterator(std::end(C)),
273 llvm::make_reverse_iterator(std::begin(C)));
274}
275
276/// An iterator adaptor that filters the elements of given inner iterators.
277///
278/// The predicate parameter should be a callable object that accepts the wrapped
279/// iterator's reference type and returns a bool. When incrementing or
280/// decrementing the iterator, it will call the predicate on each element and
281/// skip any where it returns false.
282///
283/// \code
284/// int A[] = { 1, 2, 3, 4 };
285/// auto R = make_filter_range(A, [](int N) { return N % 2 == 1; });
286/// // R contains { 1, 3 }.
287/// \endcode
288///
289/// Note: filter_iterator_base implements support for forward iteration.
290/// filter_iterator_impl exists to provide support for bidirectional iteration,
291/// conditional on whether the wrapped iterator supports it.
292template <typename WrappedIteratorT, typename PredicateT, typename IterTag>
293class filter_iterator_base
294 : public iterator_adaptor_base<
295 filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
296 WrappedIteratorT,
297 typename std::common_type<
298 IterTag, typename std::iterator_traits<
299 WrappedIteratorT>::iterator_category>::type> {
300 using BaseT = iterator_adaptor_base<
301 filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
302 WrappedIteratorT,
303 typename std::common_type<
304 IterTag, typename std::iterator_traits<
305 WrappedIteratorT>::iterator_category>::type>;
306
307protected:
308 WrappedIteratorT End;
309 PredicateT Pred;
310
311 void findNextValid() {
312 while (this->I != End && !Pred(*this->I))
313 BaseT::operator++();
314 }
315
316 // Construct the iterator. The begin iterator needs to know where the end
317 // is, so that it can properly stop when it gets there. The end iterator only
318 // needs the predicate to support bidirectional iteration.
319 filter_iterator_base(WrappedIteratorT Begin, WrappedIteratorT End,
320 PredicateT Pred)
321 : BaseT(Begin), End(End), Pred(Pred) {
322 findNextValid();
323 }
324
325public:
326 using BaseT::operator++;
327
328 filter_iterator_base &operator++() {
329 BaseT::operator++();
330 findNextValid();
331 return *this;
332 }
333};
334
335/// Specialization of filter_iterator_base for forward iteration only.
336template <typename WrappedIteratorT, typename PredicateT,
337 typename IterTag = std::forward_iterator_tag>
338class filter_iterator_impl
339 : public filter_iterator_base<WrappedIteratorT, PredicateT, IterTag> {
340 using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>;
341
342public:
343 filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
344 PredicateT Pred)
345 : BaseT(Begin, End, Pred) {}
346};
347
348/// Specialization of filter_iterator_base for bidirectional iteration.
349template <typename WrappedIteratorT, typename PredicateT>
350class filter_iterator_impl<WrappedIteratorT, PredicateT,
351 std::bidirectional_iterator_tag>
352 : public filter_iterator_base<WrappedIteratorT, PredicateT,
353 std::bidirectional_iterator_tag> {
354 using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT,
355 std::bidirectional_iterator_tag>;
356 void findPrevValid() {
357 while (!this->Pred(*this->I))
358 BaseT::operator--();
359 }
360
361public:
362 using BaseT::operator--;
363
364 filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
365 PredicateT Pred)
366 : BaseT(Begin, End, Pred) {}
367
368 filter_iterator_impl &operator--() {
369 BaseT::operator--();
370 findPrevValid();
371 return *this;
372 }
373};
374
375namespace detail {
376
377template <bool is_bidirectional> struct fwd_or_bidi_tag_impl {
378 using type = std::forward_iterator_tag;
379};
380
381template <> struct fwd_or_bidi_tag_impl<true> {
382 using type = std::bidirectional_iterator_tag;
383};
384
385/// Helper which sets its type member to forward_iterator_tag if the category
386/// of \p IterT does not derive from bidirectional_iterator_tag, and to
387/// bidirectional_iterator_tag otherwise.
388template <typename IterT> struct fwd_or_bidi_tag {
389 using type = typename fwd_or_bidi_tag_impl<std::is_base_of<
390 std::bidirectional_iterator_tag,
391 typename std::iterator_traits<IterT>::iterator_category>::value>::type;
392};
393
394} // namespace detail
395
396/// Defines filter_iterator to a suitable specialization of
397/// filter_iterator_impl, based on the underlying iterator's category.
398template <typename WrappedIteratorT, typename PredicateT>
399using filter_iterator = filter_iterator_impl<
400 WrappedIteratorT, PredicateT,
401 typename detail::fwd_or_bidi_tag<WrappedIteratorT>::type>;
402
403/// Convenience function that takes a range of elements and a predicate,
404/// and return a new filter_iterator range.
405///
406/// FIXME: Currently if RangeT && is a rvalue reference to a temporary, the
407/// lifetime of that temporary is not kept by the returned range object, and the
408/// temporary is going to be dropped on the floor after the make_iterator_range
409/// full expression that contains this function call.
410template <typename RangeT, typename PredicateT>
411iterator_range<filter_iterator<detail::IterOfRange<RangeT>, PredicateT>>
412make_filter_range(RangeT &&Range, PredicateT Pred) {
413 using FilterIteratorT =
414 filter_iterator<detail::IterOfRange<RangeT>, PredicateT>;
415 return make_range(
416 FilterIteratorT(std::begin(std::forward<RangeT>(Range)),
417 std::end(std::forward<RangeT>(Range)), Pred),
418 FilterIteratorT(std::end(std::forward<RangeT>(Range)),
419 std::end(std::forward<RangeT>(Range)), Pred));
420}
421
422/// A pseudo-iterator adaptor that is designed to implement "early increment"
423/// style loops.
424///
425/// This is *not a normal iterator* and should almost never be used directly. It
426/// is intended primarily to be used with range based for loops and some range
427/// algorithms.
428///
429/// The iterator isn't quite an `OutputIterator` or an `InputIterator` but
430/// somewhere between them. The constraints of these iterators are:
431///
432/// - On construction or after being incremented, it is comparable and
433/// dereferencable. It is *not* incrementable.
434/// - After being dereferenced, it is neither comparable nor dereferencable, it
435/// is only incrementable.
436///
437/// This means you can only dereference the iterator once, and you can only
438/// increment it once between dereferences.
439template <typename WrappedIteratorT>
440class early_inc_iterator_impl
441 : public iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
442 WrappedIteratorT, std::input_iterator_tag> {
443 using BaseT =
444 iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
445 WrappedIteratorT, std::input_iterator_tag>;
446
447 using PointerT = typename std::iterator_traits<WrappedIteratorT>::pointer;
448
449protected:
450#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
451 bool IsEarlyIncremented = false;
452#endif
453
454public:
455 early_inc_iterator_impl(WrappedIteratorT I) : BaseT(I) {}
456
457 using BaseT::operator*;
458 typename BaseT::reference operator*() {
459#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
460 assert(!IsEarlyIncremented && "Cannot dereference twice!")((!IsEarlyIncremented && "Cannot dereference twice!")
? static_cast<void> (0) : __assert_fail ("!IsEarlyIncremented && \"Cannot dereference twice!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 460, __PRETTY_FUNCTION__))
;
461 IsEarlyIncremented = true;
462#endif
463 return *(this->I)++;
464 }
465
466 using BaseT::operator++;
467 early_inc_iterator_impl &operator++() {
468#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
469 assert(IsEarlyIncremented && "Cannot increment before dereferencing!")((IsEarlyIncremented && "Cannot increment before dereferencing!"
) ? static_cast<void> (0) : __assert_fail ("IsEarlyIncremented && \"Cannot increment before dereferencing!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 469, __PRETTY_FUNCTION__))
;
470 IsEarlyIncremented = false;
471#endif
472 return *this;
473 }
474
475 using BaseT::operator==;
476 bool operator==(const early_inc_iterator_impl &RHS) const {
477#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
478 assert(!IsEarlyIncremented && "Cannot compare after dereferencing!")((!IsEarlyIncremented && "Cannot compare after dereferencing!"
) ? static_cast<void> (0) : __assert_fail ("!IsEarlyIncremented && \"Cannot compare after dereferencing!\""
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 478, __PRETTY_FUNCTION__))
;
479#endif
480 return BaseT::operator==(RHS);
481 }
482};
483
484/// Make a range that does early increment to allow mutation of the underlying
485/// range without disrupting iteration.
486///
487/// The underlying iterator will be incremented immediately after it is
488/// dereferenced, allowing deletion of the current node or insertion of nodes to
489/// not disrupt iteration provided they do not invalidate the *next* iterator --
490/// the current iterator can be invalidated.
491///
492/// This requires a very exact pattern of use that is only really suitable to
493/// range based for loops and other range algorithms that explicitly guarantee
494/// to dereference exactly once each element, and to increment exactly once each
495/// element.
496template <typename RangeT>
497iterator_range<early_inc_iterator_impl<detail::IterOfRange<RangeT>>>
498make_early_inc_range(RangeT &&Range) {
499 using EarlyIncIteratorT =
500 early_inc_iterator_impl<detail::IterOfRange<RangeT>>;
501 return make_range(EarlyIncIteratorT(std::begin(std::forward<RangeT>(Range))),
502 EarlyIncIteratorT(std::end(std::forward<RangeT>(Range))));
503}
504
505// forward declarations required by zip_shortest/zip_first
506template <typename R, typename UnaryPredicate>
507bool all_of(R &&range, UnaryPredicate P);
508
509template <size_t... I> struct index_sequence;
510
511template <class... Ts> struct index_sequence_for;
512
513namespace detail {
514
515using std::declval;
516
517// We have to alias this since inlining the actual type at the usage site
518// in the parameter list of iterator_facade_base<> below ICEs MSVC 2017.
519template<typename... Iters> struct ZipTupleType {
520 using type = std::tuple<decltype(*declval<Iters>())...>;
521};
522
523template <typename ZipType, typename... Iters>
524using zip_traits = iterator_facade_base<
525 ZipType, typename std::common_type<std::bidirectional_iterator_tag,
526 typename std::iterator_traits<
527 Iters>::iterator_category...>::type,
528 // ^ TODO: Implement random access methods.
529 typename ZipTupleType<Iters...>::type,
530 typename std::iterator_traits<typename std::tuple_element<
531 0, std::tuple<Iters...>>::type>::difference_type,
532 // ^ FIXME: This follows boost::make_zip_iterator's assumption that all
533 // inner iterators have the same difference_type. It would fail if, for
534 // instance, the second field's difference_type were non-numeric while the
535 // first is.
536 typename ZipTupleType<Iters...>::type *,
537 typename ZipTupleType<Iters...>::type>;
538
539template <typename ZipType, typename... Iters>
540struct zip_common : public zip_traits<ZipType, Iters...> {
541 using Base = zip_traits<ZipType, Iters...>;
542 using value_type = typename Base::value_type;
543
544 std::tuple<Iters...> iterators;
545
546protected:
547 template <size_t... Ns> value_type deref(index_sequence<Ns...>) const {
548 return value_type(*std::get<Ns>(iterators)...);
549 }
550
551 template <size_t... Ns>
552 decltype(iterators) tup_inc(index_sequence<Ns...>) const {
553 return std::tuple<Iters...>(std::next(std::get<Ns>(iterators))...);
554 }
555
556 template <size_t... Ns>
557 decltype(iterators) tup_dec(index_sequence<Ns...>) const {
558 return std::tuple<Iters...>(std::prev(std::get<Ns>(iterators))...);
559 }
560
561public:
562 zip_common(Iters &&... ts) : iterators(std::forward<Iters>(ts)...) {}
563
564 value_type operator*() { return deref(index_sequence_for<Iters...>{}); }
565
566 const value_type operator*() const {
567 return deref(index_sequence_for<Iters...>{});
568 }
569
570 ZipType &operator++() {
571 iterators = tup_inc(index_sequence_for<Iters...>{});
572 return *reinterpret_cast<ZipType *>(this);
573 }
574
575 ZipType &operator--() {
576 static_assert(Base::IsBidirectional,
577 "All inner iterators must be at least bidirectional.");
578 iterators = tup_dec(index_sequence_for<Iters...>{});
579 return *reinterpret_cast<ZipType *>(this);
580 }
581};
582
583template <typename... Iters>
584struct zip_first : public zip_common<zip_first<Iters...>, Iters...> {
585 using Base = zip_common<zip_first<Iters...>, Iters...>;
586
587 bool operator==(const zip_first<Iters...> &other) const {
588 return std::get<0>(this->iterators) == std::get<0>(other.iterators);
589 }
590
591 zip_first(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
592};
593
594template <typename... Iters>
595class zip_shortest : public zip_common<zip_shortest<Iters...>, Iters...> {
596 template <size_t... Ns>
597 bool test(const zip_shortest<Iters...> &other, index_sequence<Ns...>) const {
598 return all_of(std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
599 std::get<Ns>(other.iterators)...},
600 identity<bool>{});
601 }
602
603public:
604 using Base = zip_common<zip_shortest<Iters...>, Iters...>;
605
606 zip_shortest(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
607
608 bool operator==(const zip_shortest<Iters...> &other) const {
609 return !test(other, index_sequence_for<Iters...>{});
610 }
611};
612
613template <template <typename...> class ItType, typename... Args> class zippy {
614public:
615 using iterator = ItType<decltype(std::begin(std::declval<Args>()))...>;
616 using iterator_category = typename iterator::iterator_category;
617 using value_type = typename iterator::value_type;
618 using difference_type = typename iterator::difference_type;
619 using pointer = typename iterator::pointer;
620 using reference = typename iterator::reference;
621
622private:
623 std::tuple<Args...> ts;
624
625 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) const {
626 return iterator(std::begin(std::get<Ns>(ts))...);
627 }
628 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) const {
629 return iterator(std::end(std::get<Ns>(ts))...);
630 }
631
632public:
633 zippy(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
634
635 iterator begin() const { return begin_impl(index_sequence_for<Args...>{}); }
636 iterator end() const { return end_impl(index_sequence_for<Args...>{}); }
637};
638
639} // end namespace detail
640
641/// zip iterator for two or more iteratable types.
642template <typename T, typename U, typename... Args>
643detail::zippy<detail::zip_shortest, T, U, Args...> zip(T &&t, U &&u,
644 Args &&... args) {
645 return detail::zippy<detail::zip_shortest, T, U, Args...>(
646 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
647}
648
649/// zip iterator that, for the sake of efficiency, assumes the first iteratee to
650/// be the shortest.
651template <typename T, typename U, typename... Args>
652detail::zippy<detail::zip_first, T, U, Args...> zip_first(T &&t, U &&u,
653 Args &&... args) {
654 return detail::zippy<detail::zip_first, T, U, Args...>(
655 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
656}
657
658/// Iterator wrapper that concatenates sequences together.
659///
660/// This can concatenate different iterators, even with different types, into
661/// a single iterator provided the value types of all the concatenated
662/// iterators expose `reference` and `pointer` types that can be converted to
663/// `ValueT &` and `ValueT *` respectively. It doesn't support more
664/// interesting/customized pointer or reference types.
665///
666/// Currently this only supports forward or higher iterator categories as
667/// inputs and always exposes a forward iterator interface.
668template <typename ValueT, typename... IterTs>
669class concat_iterator
670 : public iterator_facade_base<concat_iterator<ValueT, IterTs...>,
671 std::forward_iterator_tag, ValueT> {
672 using BaseT = typename concat_iterator::iterator_facade_base;
673
674 /// We store both the current and end iterators for each concatenated
675 /// sequence in a tuple of pairs.
676 ///
677 /// Note that something like iterator_range seems nice at first here, but the
678 /// range properties are of little benefit and end up getting in the way
679 /// because we need to do mutation on the current iterators.
680 std::tuple<IterTs...> Begins;
681 std::tuple<IterTs...> Ends;
682
683 /// Attempts to increment a specific iterator.
684 ///
685 /// Returns true if it was able to increment the iterator. Returns false if
686 /// the iterator is already at the end iterator.
687 template <size_t Index> bool incrementHelper() {
688 auto &Begin = std::get<Index>(Begins);
689 auto &End = std::get<Index>(Ends);
690 if (Begin == End)
691 return false;
692
693 ++Begin;
694 return true;
695 }
696
697 /// Increments the first non-end iterator.
698 ///
699 /// It is an error to call this with all iterators at the end.
700 template <size_t... Ns> void increment(index_sequence<Ns...>) {
701 // Build a sequence of functions to increment each iterator if possible.
702 bool (concat_iterator::*IncrementHelperFns[])() = {
703 &concat_iterator::incrementHelper<Ns>...};
704
705 // Loop over them, and stop as soon as we succeed at incrementing one.
706 for (auto &IncrementHelperFn : IncrementHelperFns)
707 if ((this->*IncrementHelperFn)())
708 return;
709
710 llvm_unreachable("Attempted to increment an end concat iterator!")::llvm::llvm_unreachable_internal("Attempted to increment an end concat iterator!"
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 710)
;
711 }
712
713 /// Returns null if the specified iterator is at the end. Otherwise,
714 /// dereferences the iterator and returns the address of the resulting
715 /// reference.
716 template <size_t Index> ValueT *getHelper() const {
717 auto &Begin = std::get<Index>(Begins);
718 auto &End = std::get<Index>(Ends);
719 if (Begin == End)
720 return nullptr;
721
722 return &*Begin;
723 }
724
725 /// Finds the first non-end iterator, dereferences, and returns the resulting
726 /// reference.
727 ///
728 /// It is an error to call this with all iterators at the end.
729 template <size_t... Ns> ValueT &get(index_sequence<Ns...>) const {
730 // Build a sequence of functions to get from iterator if possible.
731 ValueT *(concat_iterator::*GetHelperFns[])() const = {
732 &concat_iterator::getHelper<Ns>...};
733
734 // Loop over them, and return the first result we find.
735 for (auto &GetHelperFn : GetHelperFns)
736 if (ValueT *P = (this->*GetHelperFn)())
737 return *P;
738
739 llvm_unreachable("Attempted to get a pointer from an end concat iterator!")::llvm::llvm_unreachable_internal("Attempted to get a pointer from an end concat iterator!"
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 739)
;
740 }
741
742public:
743 /// Constructs an iterator from a squence of ranges.
744 ///
745 /// We need the full range to know how to switch between each of the
746 /// iterators.
747 template <typename... RangeTs>
748 explicit concat_iterator(RangeTs &&... Ranges)
749 : Begins(std::begin(Ranges)...), Ends(std::end(Ranges)...) {}
750
751 using BaseT::operator++;
752
753 concat_iterator &operator++() {
754 increment(index_sequence_for<IterTs...>());
755 return *this;
756 }
757
758 ValueT &operator*() const { return get(index_sequence_for<IterTs...>()); }
759
760 bool operator==(const concat_iterator &RHS) const {
761 return Begins == RHS.Begins && Ends == RHS.Ends;
762 }
763};
764
765namespace detail {
766
767/// Helper to store a sequence of ranges being concatenated and access them.
768///
769/// This is designed to facilitate providing actual storage when temporaries
770/// are passed into the constructor such that we can use it as part of range
771/// based for loops.
772template <typename ValueT, typename... RangeTs> class concat_range {
773public:
774 using iterator =
775 concat_iterator<ValueT,
776 decltype(std::begin(std::declval<RangeTs &>()))...>;
777
778private:
779 std::tuple<RangeTs...> Ranges;
780
781 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) {
782 return iterator(std::get<Ns>(Ranges)...);
783 }
784 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) {
785 return iterator(make_range(std::end(std::get<Ns>(Ranges)),
786 std::end(std::get<Ns>(Ranges)))...);
787 }
788
789public:
790 concat_range(RangeTs &&... Ranges)
791 : Ranges(std::forward<RangeTs>(Ranges)...) {}
792
793 iterator begin() { return begin_impl(index_sequence_for<RangeTs...>{}); }
794 iterator end() { return end_impl(index_sequence_for<RangeTs...>{}); }
795};
796
797} // end namespace detail
798
799/// Concatenated range across two or more ranges.
800///
801/// The desired value type must be explicitly specified.
802template <typename ValueT, typename... RangeTs>
803detail::concat_range<ValueT, RangeTs...> concat(RangeTs &&... Ranges) {
804 static_assert(sizeof...(RangeTs) > 1,
805 "Need more than one range to concatenate!");
806 return detail::concat_range<ValueT, RangeTs...>(
807 std::forward<RangeTs>(Ranges)...);
808}
809
810//===----------------------------------------------------------------------===//
811// Extra additions to <utility>
812//===----------------------------------------------------------------------===//
813
814/// Function object to check whether the first component of a std::pair
815/// compares less than the first component of another std::pair.
816struct less_first {
817 template <typename T> bool operator()(const T &lhs, const T &rhs) const {
818 return lhs.first < rhs.first;
819 }
820};
821
822/// Function object to check whether the second component of a std::pair
823/// compares less than the second component of another std::pair.
824struct less_second {
825 template <typename T> bool operator()(const T &lhs, const T &rhs) const {
826 return lhs.second < rhs.second;
827 }
828};
829
830/// \brief Function object to apply a binary function to the first component of
831/// a std::pair.
832template<typename FuncTy>
833struct on_first {
834 FuncTy func;
835
836 template <typename T>
837 auto operator()(const T &lhs, const T &rhs) const
838 -> decltype(func(lhs.first, rhs.first)) {
839 return func(lhs.first, rhs.first);
840 }
841};
842
843// A subset of N3658. More stuff can be added as-needed.
844
845/// Represents a compile-time sequence of integers.
846template <class T, T... I> struct integer_sequence {
847 using value_type = T;
848
849 static constexpr size_t size() { return sizeof...(I); }
850};
851
852/// Alias for the common case of a sequence of size_ts.
853template <size_t... I>
854struct index_sequence : integer_sequence<std::size_t, I...> {};
855
856template <std::size_t N, std::size_t... I>
857struct build_index_impl : build_index_impl<N - 1, N - 1, I...> {};
858template <std::size_t... I>
859struct build_index_impl<0, I...> : index_sequence<I...> {};
860
861/// Creates a compile-time integer sequence for a parameter pack.
862template <class... Ts>
863struct index_sequence_for : build_index_impl<sizeof...(Ts)> {};
864
865/// Utility type to build an inheritance chain that makes it easy to rank
866/// overload candidates.
867template <int N> struct rank : rank<N - 1> {};
868template <> struct rank<0> {};
869
870/// traits class for checking whether type T is one of any of the given
871/// types in the variadic list.
872template <typename T, typename... Ts> struct is_one_of {
873 static const bool value = false;
874};
875
876template <typename T, typename U, typename... Ts>
877struct is_one_of<T, U, Ts...> {
878 static const bool value =
879 std::is_same<T, U>::value || is_one_of<T, Ts...>::value;
880};
881
882/// traits class for checking whether type T is a base class for all
883/// the given types in the variadic list.
884template <typename T, typename... Ts> struct are_base_of {
885 static const bool value = true;
886};
887
888template <typename T, typename U, typename... Ts>
889struct are_base_of<T, U, Ts...> {
890 static const bool value =
891 std::is_base_of<T, U>::value && are_base_of<T, Ts...>::value;
892};
893
894//===----------------------------------------------------------------------===//
895// Extra additions for arrays
896//===----------------------------------------------------------------------===//
897
898/// Find the length of an array.
899template <class T, std::size_t N>
900constexpr inline size_t array_lengthof(T (&)[N]) {
901 return N;
902}
903
904/// Adapt std::less<T> for array_pod_sort.
905template<typename T>
906inline int array_pod_sort_comparator(const void *P1, const void *P2) {
907 if (std::less<T>()(*reinterpret_cast<const T*>(P1),
908 *reinterpret_cast<const T*>(P2)))
909 return -1;
910 if (std::less<T>()(*reinterpret_cast<const T*>(P2),
911 *reinterpret_cast<const T*>(P1)))
912 return 1;
913 return 0;
914}
915
916/// get_array_pod_sort_comparator - This is an internal helper function used to
917/// get type deduction of T right.
918template<typename T>
919inline int (*get_array_pod_sort_comparator(const T &))
920 (const void*, const void*) {
921 return array_pod_sort_comparator<T>;
922}
923
924/// array_pod_sort - This sorts an array with the specified start and end
925/// extent. This is just like std::sort, except that it calls qsort instead of
926/// using an inlined template. qsort is slightly slower than std::sort, but
927/// most sorts are not performance critical in LLVM and std::sort has to be
928/// template instantiated for each type, leading to significant measured code
929/// bloat. This function should generally be used instead of std::sort where
930/// possible.
931///
932/// This function assumes that you have simple POD-like types that can be
933/// compared with std::less and can be moved with memcpy. If this isn't true,
934/// you should use std::sort.
935///
936/// NOTE: If qsort_r were portable, we could allow a custom comparator and
937/// default to std::less.
938template<class IteratorTy>
939inline void array_pod_sort(IteratorTy Start, IteratorTy End) {
940 // Don't inefficiently call qsort with one element or trigger undefined
941 // behavior with an empty sequence.
942 auto NElts = End - Start;
943 if (NElts <= 1) return;
944#ifdef EXPENSIVE_CHECKS
945 std::mt19937 Generator(std::random_device{}());
946 std::shuffle(Start, End, Generator);
947#endif
948 qsort(&*Start, NElts, sizeof(*Start), get_array_pod_sort_comparator(*Start));
949}
950
951template <class IteratorTy>
952inline void array_pod_sort(
953 IteratorTy Start, IteratorTy End,
954 int (*Compare)(
955 const typename std::iterator_traits<IteratorTy>::value_type *,
956 const typename std::iterator_traits<IteratorTy>::value_type *)) {
957 // Don't inefficiently call qsort with one element or trigger undefined
958 // behavior with an empty sequence.
959 auto NElts = End - Start;
960 if (NElts <= 1) return;
961#ifdef EXPENSIVE_CHECKS
962 std::mt19937 Generator(std::random_device{}());
963 std::shuffle(Start, End, Generator);
964#endif
965 qsort(&*Start, NElts, sizeof(*Start),
966 reinterpret_cast<int (*)(const void *, const void *)>(Compare));
967}
968
969// Provide wrappers to std::sort which shuffle the elements before sorting
970// to help uncover non-deterministic behavior (PR35135).
971template <typename IteratorTy>
972inline void sort(IteratorTy Start, IteratorTy End) {
973#ifdef EXPENSIVE_CHECKS
974 std::mt19937 Generator(std::random_device{}());
975 std::shuffle(Start, End, Generator);
976#endif
977 std::sort(Start, End);
978}
979
980template <typename Container> inline void sort(Container &&C) {
981 llvm::sort(adl_begin(C), adl_end(C));
982}
983
984template <typename IteratorTy, typename Compare>
985inline void sort(IteratorTy Start, IteratorTy End, Compare Comp) {
986#ifdef EXPENSIVE_CHECKS
987 std::mt19937 Generator(std::random_device{}());
988 std::shuffle(Start, End, Generator);
989#endif
990 std::sort(Start, End, Comp);
991}
992
993template <typename Container, typename Compare>
994inline void sort(Container &&C, Compare Comp) {
995 llvm::sort(adl_begin(C), adl_end(C), Comp);
996}
997
998//===----------------------------------------------------------------------===//
999// Extra additions to <algorithm>
1000//===----------------------------------------------------------------------===//
1001
1002/// For a container of pointers, deletes the pointers and then clears the
1003/// container.
1004template<typename Container>
1005void DeleteContainerPointers(Container &C) {
1006 for (auto V : C)
1007 delete V;
1008 C.clear();
1009}
1010
1011/// In a container of pairs (usually a map) whose second element is a pointer,
1012/// deletes the second elements and then clears the container.
1013template<typename Container>
1014void DeleteContainerSeconds(Container &C) {
1015 for (auto &V : C)
1016 delete V.second;
1017 C.clear();
1018}
1019
1020/// Get the size of a range. This is a wrapper function around std::distance
1021/// which is only enabled when the operation is O(1).
1022template <typename R>
1023auto size(R &&Range, typename std::enable_if<
1024 std::is_same<typename std::iterator_traits<decltype(
1025 Range.begin())>::iterator_category,
1026 std::random_access_iterator_tag>::value,
1027 void>::type * = nullptr)
1028 -> decltype(std::distance(Range.begin(), Range.end())) {
1029 return std::distance(Range.begin(), Range.end());
1030}
1031
1032/// Provide wrappers to std::for_each which take ranges instead of having to
1033/// pass begin/end explicitly.
1034template <typename R, typename UnaryPredicate>
1035UnaryPredicate for_each(R &&Range, UnaryPredicate P) {
1036 return std::for_each(adl_begin(Range), adl_end(Range), P);
1037}
1038
1039/// Provide wrappers to std::all_of which take ranges instead of having to pass
1040/// begin/end explicitly.
1041template <typename R, typename UnaryPredicate>
1042bool all_of(R &&Range, UnaryPredicate P) {
1043 return std::all_of(adl_begin(Range), adl_end(Range), P);
1044}
1045
1046/// Provide wrappers to std::any_of which take ranges instead of having to pass
1047/// begin/end explicitly.
1048template <typename R, typename UnaryPredicate>
1049bool any_of(R &&Range, UnaryPredicate P) {
1050 return std::any_of(adl_begin(Range), adl_end(Range), P);
1051}
1052
1053/// Provide wrappers to std::none_of which take ranges instead of having to pass
1054/// begin/end explicitly.
1055template <typename R, typename UnaryPredicate>
1056bool none_of(R &&Range, UnaryPredicate P) {
1057 return std::none_of(adl_begin(Range), adl_end(Range), P);
1058}
1059
1060/// Provide wrappers to std::find which take ranges instead of having to pass
1061/// begin/end explicitly.
1062template <typename R, typename T>
1063auto find(R &&Range, const T &Val) -> decltype(adl_begin(Range)) {
1064 return std::find(adl_begin(Range), adl_end(Range), Val);
1065}
1066
1067/// Provide wrappers to std::find_if which take ranges instead of having to pass
1068/// begin/end explicitly.
1069template <typename R, typename UnaryPredicate>
1070auto find_if(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1071 return std::find_if(adl_begin(Range), adl_end(Range), P);
1072}
1073
1074template <typename R, typename UnaryPredicate>
1075auto find_if_not(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1076 return std::find_if_not(adl_begin(Range), adl_end(Range), P);
1077}
1078
1079/// Provide wrappers to std::remove_if which take ranges instead of having to
1080/// pass begin/end explicitly.
1081template <typename R, typename UnaryPredicate>
1082auto remove_if(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1083 return std::remove_if(adl_begin(Range), adl_end(Range), P);
1084}
1085
1086/// Provide wrappers to std::copy_if which take ranges instead of having to
1087/// pass begin/end explicitly.
1088template <typename R, typename OutputIt, typename UnaryPredicate>
1089OutputIt copy_if(R &&Range, OutputIt Out, UnaryPredicate P) {
1090 return std::copy_if(adl_begin(Range), adl_end(Range), Out, P);
1091}
1092
1093template <typename R, typename OutputIt>
1094OutputIt copy(R &&Range, OutputIt Out) {
1095 return std::copy(adl_begin(Range), adl_end(Range), Out);
1096}
1097
1098/// Wrapper function around std::find to detect if an element exists
1099/// in a container.
1100template <typename R, typename E>
1101bool is_contained(R &&Range, const E &Element) {
1102 return std::find(adl_begin(Range), adl_end(Range), Element) != adl_end(Range);
1103}
1104
1105/// Wrapper function around std::count to count the number of times an element
1106/// \p Element occurs in the given range \p Range.
1107template <typename R, typename E>
1108auto count(R &&Range, const E &Element) ->
1109 typename std::iterator_traits<decltype(adl_begin(Range))>::difference_type {
1110 return std::count(adl_begin(Range), adl_end(Range), Element);
1111}
1112
1113/// Wrapper function around std::count_if to count the number of times an
1114/// element satisfying a given predicate occurs in a range.
1115template <typename R, typename UnaryPredicate>
1116auto count_if(R &&Range, UnaryPredicate P) ->
1117 typename std::iterator_traits<decltype(adl_begin(Range))>::difference_type {
1118 return std::count_if(adl_begin(Range), adl_end(Range), P);
1119}
1120
1121/// Wrapper function around std::transform to apply a function to a range and
1122/// store the result elsewhere.
1123template <typename R, typename OutputIt, typename UnaryPredicate>
1124OutputIt transform(R &&Range, OutputIt d_first, UnaryPredicate P) {
1125 return std::transform(adl_begin(Range), adl_end(Range), d_first, P);
1126}
1127
1128/// Provide wrappers to std::partition which take ranges instead of having to
1129/// pass begin/end explicitly.
1130template <typename R, typename UnaryPredicate>
1131auto partition(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1132 return std::partition(adl_begin(Range), adl_end(Range), P);
1133}
1134
1135/// Provide wrappers to std::lower_bound which take ranges instead of having to
1136/// pass begin/end explicitly.
1137template <typename R, typename ForwardIt>
1138auto lower_bound(R &&Range, ForwardIt I) -> decltype(adl_begin(Range)) {
1139 return std::lower_bound(adl_begin(Range), adl_end(Range), I);
1140}
1141
1142template <typename R, typename ForwardIt, typename Compare>
1143auto lower_bound(R &&Range, ForwardIt I, Compare C)
1144 -> decltype(adl_begin(Range)) {
1145 return std::lower_bound(adl_begin(Range), adl_end(Range), I, C);
1146}
1147
1148/// Provide wrappers to std::upper_bound which take ranges instead of having to
1149/// pass begin/end explicitly.
1150template <typename R, typename ForwardIt>
1151auto upper_bound(R &&Range, ForwardIt I) -> decltype(adl_begin(Range)) {
1152 return std::upper_bound(adl_begin(Range), adl_end(Range), I);
1153}
1154
1155template <typename R, typename ForwardIt, typename Compare>
1156auto upper_bound(R &&Range, ForwardIt I, Compare C)
1157 -> decltype(adl_begin(Range)) {
1158 return std::upper_bound(adl_begin(Range), adl_end(Range), I, C);
1159}
1160/// Wrapper function around std::equal to detect if all elements
1161/// in a container are same.
1162template <typename R>
1163bool is_splat(R &&Range) {
1164 size_t range_size = size(Range);
1165 return range_size != 0 && (range_size == 1 ||
1166 std::equal(adl_begin(Range) + 1, adl_end(Range), adl_begin(Range)));
1167}
1168
1169/// Given a range of type R, iterate the entire range and return a
1170/// SmallVector with elements of the vector. This is useful, for example,
1171/// when you want to iterate a range and then sort the results.
1172template <unsigned Size, typename R>
1173SmallVector<typename std::remove_const<detail::ValueOfRange<R>>::type, Size>
1174to_vector(R &&Range) {
1175 return {adl_begin(Range), adl_end(Range)};
1176}
1177
1178/// Provide a container algorithm similar to C++ Library Fundamentals v2's
1179/// `erase_if` which is equivalent to:
1180///
1181/// C.erase(remove_if(C, pred), C.end());
1182///
1183/// This version works for any container with an erase method call accepting
1184/// two iterators.
1185template <typename Container, typename UnaryPredicate>
1186void erase_if(Container &C, UnaryPredicate P) {
1187 C.erase(remove_if(C, P), C.end());
1188}
1189
1190//===----------------------------------------------------------------------===//
1191// Extra additions to <memory>
1192//===----------------------------------------------------------------------===//
1193
1194// Implement make_unique according to N3656.
1195
1196/// Constructs a `new T()` with the given args and returns a
1197/// `unique_ptr<T>` which owns the object.
1198///
1199/// Example:
1200///
1201/// auto p = make_unique<int>();
1202/// auto p = make_unique<std::tuple<int, int>>(0, 1);
1203template <class T, class... Args>
1204typename std::enable_if<!std::is_array<T>::value, std::unique_ptr<T>>::type
1205make_unique(Args &&... args) {
1206 return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
20
Memory is allocated
1207}
1208
1209/// Constructs a `new T[n]` with the given args and returns a
1210/// `unique_ptr<T[]>` which owns the object.
1211///
1212/// \param n size of the new array.
1213///
1214/// Example:
1215///
1216/// auto p = make_unique<int[]>(2); // value-initializes the array with 0's.
1217template <class T>
1218typename std::enable_if<std::is_array<T>::value && std::extent<T>::value == 0,
1219 std::unique_ptr<T>>::type
1220make_unique(size_t n) {
1221 return std::unique_ptr<T>(new typename std::remove_extent<T>::type[n]());
1222}
1223
1224/// This function isn't used and is only here to provide better compile errors.
1225template <class T, class... Args>
1226typename std::enable_if<std::extent<T>::value != 0>::type
1227make_unique(Args &&...) = delete;
1228
1229struct FreeDeleter {
1230 void operator()(void* v) {
1231 ::free(v);
1232 }
1233};
1234
1235template<typename First, typename Second>
1236struct pair_hash {
1237 size_t operator()(const std::pair<First, Second> &P) const {
1238 return std::hash<First>()(P.first) * 31 + std::hash<Second>()(P.second);
1239 }
1240};
1241
1242/// A functor like C++14's std::less<void> in its absence.
1243struct less {
1244 template <typename A, typename B> bool operator()(A &&a, B &&b) const {
1245 return std::forward<A>(a) < std::forward<B>(b);
1246 }
1247};
1248
1249/// A functor like C++14's std::equal<void> in its absence.
1250struct equal {
1251 template <typename A, typename B> bool operator()(A &&a, B &&b) const {
1252 return std::forward<A>(a) == std::forward<B>(b);
1253 }
1254};
1255
1256/// Binary functor that adapts to any other binary functor after dereferencing
1257/// operands.
1258template <typename T> struct deref {
1259 T func;
1260
1261 // Could be further improved to cope with non-derivable functors and
1262 // non-binary functors (should be a variadic template member function
1263 // operator()).
1264 template <typename A, typename B>
1265 auto operator()(A &lhs, B &rhs) const -> decltype(func(*lhs, *rhs)) {
1266 assert(lhs)((lhs) ? static_cast<void> (0) : __assert_fail ("lhs", "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 1266, __PRETTY_FUNCTION__))
;
1267 assert(rhs)((rhs) ? static_cast<void> (0) : __assert_fail ("rhs", "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 1267, __PRETTY_FUNCTION__))
;
1268 return func(*lhs, *rhs);
1269 }
1270};
1271
1272namespace detail {
1273
1274template <typename R> class enumerator_iter;
1275
1276template <typename R> struct result_pair {
1277 friend class enumerator_iter<R>;
1278
1279 result_pair() = default;
1280 result_pair(std::size_t Index, IterOfRange<R> Iter)
1281 : Index(Index), Iter(Iter) {}
1282
1283 result_pair<R> &operator=(const result_pair<R> &Other) {
1284 Index = Other.Index;
1285 Iter = Other.Iter;
1286 return *this;
1287 }
1288
1289 std::size_t index() const { return Index; }
1290 const ValueOfRange<R> &value() const { return *Iter; }
1291 ValueOfRange<R> &value() { return *Iter; }
1292
1293private:
1294 std::size_t Index = std::numeric_limits<std::size_t>::max();
1295 IterOfRange<R> Iter;
1296};
1297
1298template <typename R>
1299class enumerator_iter
1300 : public iterator_facade_base<
1301 enumerator_iter<R>, std::forward_iterator_tag, result_pair<R>,
1302 typename std::iterator_traits<IterOfRange<R>>::difference_type,
1303 typename std::iterator_traits<IterOfRange<R>>::pointer,
1304 typename std::iterator_traits<IterOfRange<R>>::reference> {
1305 using result_type = result_pair<R>;
1306
1307public:
1308 explicit enumerator_iter(IterOfRange<R> EndIter)
1309 : Result(std::numeric_limits<size_t>::max(), EndIter) {}
1310
1311 enumerator_iter(std::size_t Index, IterOfRange<R> Iter)
1312 : Result(Index, Iter) {}
1313
1314 result_type &operator*() { return Result; }
1315 const result_type &operator*() const { return Result; }
1316
1317 enumerator_iter<R> &operator++() {
1318 assert(Result.Index != std::numeric_limits<size_t>::max())((Result.Index != std::numeric_limits<size_t>::max()) ?
static_cast<void> (0) : __assert_fail ("Result.Index != std::numeric_limits<size_t>::max()"
, "/build/llvm-toolchain-snapshot-8~svn345461/include/llvm/ADT/STLExtras.h"
, 1318, __PRETTY_FUNCTION__))
;
1319 ++Result.Iter;
1320 ++Result.Index;
1321 return *this;
1322 }
1323
1324 bool operator==(const enumerator_iter<R> &RHS) const {
1325 // Don't compare indices here, only iterators. It's possible for an end
1326 // iterator to have different indices depending on whether it was created
1327 // by calling std::end() versus incrementing a valid iterator.
1328 return Result.Iter == RHS.Result.Iter;
1329 }
1330
1331 enumerator_iter<R> &operator=(const enumerator_iter<R> &Other) {
1332 Result = Other.Result;
1333 return *this;
1334 }
1335
1336private:
1337 result_type Result;
1338};
1339
1340template <typename R> class enumerator {
1341public:
1342 explicit enumerator(R &&Range) : TheRange(std::forward<R>(Range)) {}
1343
1344 enumerator_iter<R> begin() {
1345 return enumerator_iter<R>(0, std::begin(TheRange));
1346 }
1347
1348 enumerator_iter<R> end() {
1349 return enumerator_iter<R>(std::end(TheRange));
1350 }
1351
1352private:
1353 R TheRange;
1354};
1355
1356} // end namespace detail
1357
1358/// Given an input range, returns a new range whose values are are pair (A,B)
1359/// such that A is the 0-based index of the item in the sequence, and B is
1360/// the value from the original sequence. Example:
1361///
1362/// std::vector<char> Items = {'A', 'B', 'C', 'D'};
1363/// for (auto X : enumerate(Items)) {
1364/// printf("Item %d - %c\n", X.index(), X.value());
1365/// }
1366///
1367/// Output:
1368/// Item 0 - A
1369/// Item 1 - B
1370/// Item 2 - C
1371/// Item 3 - D
1372///
1373template <typename R> detail::enumerator<R> enumerate(R &&TheRange) {
1374 return detail::enumerator<R>(std::forward<R>(TheRange));
1375}
1376
1377namespace detail {
1378
1379template <typename F, typename Tuple, std::size_t... I>
1380auto apply_tuple_impl(F &&f, Tuple &&t, index_sequence<I...>)
1381 -> decltype(std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...)) {
1382 return std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...);
1383}
1384
1385} // end namespace detail
1386
1387/// Given an input tuple (a1, a2, ..., an), pass the arguments of the
1388/// tuple variadically to f as if by calling f(a1, a2, ..., an) and
1389/// return the result.
1390template <typename F, typename Tuple>
1391auto apply_tuple(F &&f, Tuple &&t) -> decltype(detail::apply_tuple_impl(
1392 std::forward<F>(f), std::forward<Tuple>(t),
1393 build_index_impl<
1394 std::tuple_size<typename std::decay<Tuple>::type>::value>{})) {
1395 using Indices = build_index_impl<
1396 std::tuple_size<typename std::decay<Tuple>::type>::value>;
1397
1398 return detail::apply_tuple_impl(std::forward<F>(f), std::forward<Tuple>(t),
1399 Indices{});
1400}
1401
1402} // end namespace llvm
1403
1404#endif // LLVM_ADT_STLEXTRAS_H