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

Press '?' to see keyboard shortcuts

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 -analyzer-config-compatibility-mode=true -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~svn350071/build-llvm/lib/Linker -I /build/llvm-toolchain-snapshot-8~svn350071/lib/Linker -I /build/llvm-toolchain-snapshot-8~svn350071/build-llvm/include -I /build/llvm-toolchain-snapshot-8~svn350071/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~svn350071/build-llvm/lib/Linker -fdebug-prefix-map=/build/llvm-toolchain-snapshot-8~svn350071=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-12-27-042839-1215-1 -x c++ /build/llvm-toolchain-snapshot-8~svn350071/lib/Linker/IRMover.cpp -faddrsig

/build/llvm-toolchain-snapshot-8~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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());
19
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~svn350071/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") {
10
Assuming the condition is false
11
Assuming the condition is false
12
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) {
13
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) {
14
Taking true branch
820 ArrayType *DstTy = cast<ArrayType>(DstGV->getValueType());
821 DstNumElements = DstTy->getNumElements();
822
823 if (!SrcGV->hasAppendingLinkage() || !DstGV->hasAppendingLinkage())
15
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())
16
Assuming the condition is true
17
Taking true branch
831 return stringErr("Appending variables with different element types!");
18
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~svn350071/lib/Linker/IRMover.cpp"
, 935, __PRETTY_FUNCTION__))
;
7
'?' condition is true
936 if (SGV->hasAppendingLinkage())
8
Taking true branch
937 return linkAppendingVarProto(cast_or_null<GlobalVariable>(DGV),
9
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~svn350071/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~svn350071/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 // The original definition (or at least its debug info - if the variable is
1066 // internalized an optimized away) will remain in the source module, so
1067 // there's no need to import them.
1068 // If LLVM ever does more advanced optimizations on global variables
1069 // (removing/localizing write operations, for instance) that can track
1070 // through debug info, this decision may need to be revisited - but do so
1071 // with care when it comes to debug info size. Emitting small CUs containing
1072 // only a few imported entities into every destination module may be very
1073 // size inefficient.
1074 ValueMap.MD()[CU->getRawGlobalVariables()].reset(nullptr);
1075
1076 // Imported entities only need to be mapped in if they have local
1077 // scope, as those might correspond to an imported entity inside a
1078 // function being imported (any locally scoped imported entities that
1079 // don't end up referenced by an imported function will not be emitted
1080 // into the object). Imported entities not in a local scope
1081 // (e.g. on the namespace) only need to be emitted by the originating
1082 // module. Create a list of the locally scoped imported entities, and
1083 // replace the source CUs imported entity list with the new list, so
1084 // only those are mapped in.
1085 // FIXME: Locally-scoped imported entities could be moved to the
1086 // functions they are local to instead of listing them on the CU, and
1087 // we would naturally only link in those needed by function importing.
1088 SmallVector<TrackingMDNodeRef, 4> AllImportedModules;
1089 bool ReplaceImportedEntities = false;
1090 for (auto *IE : CU->getImportedEntities()) {
1091 DIScope *Scope = IE->getScope();
1092 assert(Scope && "Invalid Scope encoding!")((Scope && "Invalid Scope encoding!") ? static_cast<
void> (0) : __assert_fail ("Scope && \"Invalid Scope encoding!\""
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/Linker/IRMover.cpp"
, 1092, __PRETTY_FUNCTION__))
;
1093 if (isa<DILocalScope>(Scope))
1094 AllImportedModules.emplace_back(IE);
1095 else
1096 ReplaceImportedEntities = true;
1097 }
1098 if (ReplaceImportedEntities) {
1099 if (!AllImportedModules.empty())
1100 CU->replaceImportedEntities(MDTuple::get(
1101 CU->getContext(),
1102 SmallVector<Metadata *, 16>(AllImportedModules.begin(),
1103 AllImportedModules.end())));
1104 else
1105 // If there were no local scope imported entities, we can map
1106 // the whole list to nullptr.
1107 ValueMap.MD()[CU->getRawImportedEntities()].reset(nullptr);
1108 }
1109 }
1110}
1111
1112/// Insert all of the named MDNodes in Src into the Dest module.
1113void IRLinker::linkNamedMDNodes() {
1114 const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
1115 for (const NamedMDNode &NMD : SrcM->named_metadata()) {
1116 // Don't link module flags here. Do them separately.
1117 if (&NMD == SrcModFlags)
1118 continue;
1119 NamedMDNode *DestNMD = DstM.getOrInsertNamedMetadata(NMD.getName());
1120 // Add Src elements into Dest node.
1121 for (const MDNode *Op : NMD.operands())
1122 DestNMD->addOperand(Mapper.mapMDNode(*Op));
1123 }
1124}
1125
1126/// Merge the linker flags in Src into the Dest module.
1127Error IRLinker::linkModuleFlagsMetadata() {
1128 // If the source module has no module flags, we are done.
1129 const NamedMDNode *SrcModFlags = SrcM->getModuleFlagsMetadata();
1130 if (!SrcModFlags)
1131 return Error::success();
1132
1133 // If the destination module doesn't have module flags yet, then just copy
1134 // over the source module's flags.
1135 NamedMDNode *DstModFlags = DstM.getOrInsertModuleFlagsMetadata();
1136 if (DstModFlags->getNumOperands() == 0) {
1137 for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I)
1138 DstModFlags->addOperand(SrcModFlags->getOperand(I));
1139
1140 return Error::success();
1141 }
1142
1143 // First build a map of the existing module flags and requirements.
1144 DenseMap<MDString *, std::pair<MDNode *, unsigned>> Flags;
1145 SmallSetVector<MDNode *, 16> Requirements;
1146 for (unsigned I = 0, E = DstModFlags->getNumOperands(); I != E; ++I) {
1147 MDNode *Op = DstModFlags->getOperand(I);
1148 ConstantInt *Behavior = mdconst::extract<ConstantInt>(Op->getOperand(0));
1149 MDString *ID = cast<MDString>(Op->getOperand(1));
1150
1151 if (Behavior->getZExtValue() == Module::Require) {
1152 Requirements.insert(cast<MDNode>(Op->getOperand(2)));
1153 } else {
1154 Flags[ID] = std::make_pair(Op, I);
1155 }
1156 }
1157
1158 // Merge in the flags from the source module, and also collect its set of
1159 // requirements.
1160 for (unsigned I = 0, E = SrcModFlags->getNumOperands(); I != E; ++I) {
1161 MDNode *SrcOp = SrcModFlags->getOperand(I);
1162 ConstantInt *SrcBehavior =
1163 mdconst::extract<ConstantInt>(SrcOp->getOperand(0));
1164 MDString *ID = cast<MDString>(SrcOp->getOperand(1));
1165 MDNode *DstOp;
1166 unsigned DstIndex;
1167 std::tie(DstOp, DstIndex) = Flags.lookup(ID);
1168 unsigned SrcBehaviorValue = SrcBehavior->getZExtValue();
1169
1170 // If this is a requirement, add it and continue.
1171 if (SrcBehaviorValue == Module::Require) {
1172 // If the destination module does not already have this requirement, add
1173 // it.
1174 if (Requirements.insert(cast<MDNode>(SrcOp->getOperand(2)))) {
1175 DstModFlags->addOperand(SrcOp);
1176 }
1177 continue;
1178 }
1179
1180 // If there is no existing flag with this ID, just add it.
1181 if (!DstOp) {
1182 Flags[ID] = std::make_pair(SrcOp, DstModFlags->getNumOperands());
1183 DstModFlags->addOperand(SrcOp);
1184 continue;
1185 }
1186
1187 // Otherwise, perform a merge.
1188 ConstantInt *DstBehavior =
1189 mdconst::extract<ConstantInt>(DstOp->getOperand(0));
1190 unsigned DstBehaviorValue = DstBehavior->getZExtValue();
1191
1192 auto overrideDstValue = [&]() {
1193 DstModFlags->setOperand(DstIndex, SrcOp);
1194 Flags[ID].first = SrcOp;
1195 };
1196
1197 // If either flag has override behavior, handle it first.
1198 if (DstBehaviorValue == Module::Override) {
1199 // Diagnose inconsistent flags which both have override behavior.
1200 if (SrcBehaviorValue == Module::Override &&
1201 SrcOp->getOperand(2) != DstOp->getOperand(2))
1202 return stringErr("linking module flags '" + ID->getString() +
1203 "': IDs have conflicting override values");
1204 continue;
1205 } else if (SrcBehaviorValue == Module::Override) {
1206 // Update the destination flag to that of the source.
1207 overrideDstValue();
1208 continue;
1209 }
1210
1211 // Diagnose inconsistent merge behavior types.
1212 if (SrcBehaviorValue != DstBehaviorValue)
1213 return stringErr("linking module flags '" + ID->getString() +
1214 "': IDs have conflicting behaviors");
1215
1216 auto replaceDstValue = [&](MDNode *New) {
1217 Metadata *FlagOps[] = {DstOp->getOperand(0), ID, New};
1218 MDNode *Flag = MDNode::get(DstM.getContext(), FlagOps);
1219 DstModFlags->setOperand(DstIndex, Flag);
1220 Flags[ID].first = Flag;
1221 };
1222
1223 // Perform the merge for standard behavior types.
1224 switch (SrcBehaviorValue) {
1225 case Module::Require:
1226 case Module::Override:
1227 llvm_unreachable("not possible")::llvm::llvm_unreachable_internal("not possible", "/build/llvm-toolchain-snapshot-8~svn350071/lib/Linker/IRMover.cpp"
, 1227)
;
1228 case Module::Error: {
1229 // Emit an error if the values differ.
1230 if (SrcOp->getOperand(2) != DstOp->getOperand(2))
1231 return stringErr("linking module flags '" + ID->getString() +
1232 "': IDs have conflicting values");
1233 continue;
1234 }
1235 case Module::Warning: {
1236 // Emit a warning if the values differ.
1237 if (SrcOp->getOperand(2) != DstOp->getOperand(2)) {
1238 std::string str;
1239 raw_string_ostream(str)
1240 << "linking module flags '" << ID->getString()
1241 << "': IDs have conflicting values ('" << *SrcOp->getOperand(2)
1242 << "' from " << SrcM->getModuleIdentifier() << " with '"
1243 << *DstOp->getOperand(2) << "' from " << DstM.getModuleIdentifier()
1244 << ')';
1245 emitWarning(str);
1246 }
1247 continue;
1248 }
1249 case Module::Max: {
1250 ConstantInt *DstValue =
1251 mdconst::extract<ConstantInt>(DstOp->getOperand(2));
1252 ConstantInt *SrcValue =
1253 mdconst::extract<ConstantInt>(SrcOp->getOperand(2));
1254 if (SrcValue->getZExtValue() > DstValue->getZExtValue())
1255 overrideDstValue();
1256 break;
1257 }
1258 case Module::Append: {
1259 MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
1260 MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
1261 SmallVector<Metadata *, 8> MDs;
1262 MDs.reserve(DstValue->getNumOperands() + SrcValue->getNumOperands());
1263 MDs.append(DstValue->op_begin(), DstValue->op_end());
1264 MDs.append(SrcValue->op_begin(), SrcValue->op_end());
1265
1266 replaceDstValue(MDNode::get(DstM.getContext(), MDs));
1267 break;
1268 }
1269 case Module::AppendUnique: {
1270 SmallSetVector<Metadata *, 16> Elts;
1271 MDNode *DstValue = cast<MDNode>(DstOp->getOperand(2));
1272 MDNode *SrcValue = cast<MDNode>(SrcOp->getOperand(2));
1273 Elts.insert(DstValue->op_begin(), DstValue->op_end());
1274 Elts.insert(SrcValue->op_begin(), SrcValue->op_end());
1275
1276 replaceDstValue(MDNode::get(DstM.getContext(),
1277 makeArrayRef(Elts.begin(), Elts.end())));
1278 break;
1279 }
1280 }
1281 }
1282
1283 // Check all of the requirements.
1284 for (unsigned I = 0, E = Requirements.size(); I != E; ++I) {
1285 MDNode *Requirement = Requirements[I];
1286 MDString *Flag = cast<MDString>(Requirement->getOperand(0));
1287 Metadata *ReqValue = Requirement->getOperand(1);
1288
1289 MDNode *Op = Flags[Flag].first;
1290 if (!Op || Op->getOperand(2) != ReqValue)
1291 return stringErr("linking module flags '" + Flag->getString() +
1292 "': does not have the required value");
1293 }
1294 return Error::success();
1295}
1296
1297/// Return InlineAsm adjusted with target-specific directives if required.
1298/// For ARM and Thumb, we have to add directives to select the appropriate ISA
1299/// to support mixing module-level inline assembly from ARM and Thumb modules.
1300static std::string adjustInlineAsm(const std::string &InlineAsm,
1301 const Triple &Triple) {
1302 if (Triple.getArch() == Triple::thumb || Triple.getArch() == Triple::thumbeb)
1303 return ".text\n.balign 2\n.thumb\n" + InlineAsm;
1304 if (Triple.getArch() == Triple::arm || Triple.getArch() == Triple::armeb)
1305 return ".text\n.balign 4\n.arm\n" + InlineAsm;
1306 return InlineAsm;
1307}
1308
1309Error IRLinker::run() {
1310 // Ensure metadata materialized before value mapping.
1311 if (SrcM->getMaterializer())
1312 if (Error Err = SrcM->getMaterializer()->materializeMetadata())
1313 return Err;
1314
1315 // Inherit the target data from the source module if the destination module
1316 // doesn't have one already.
1317 if (DstM.getDataLayout().isDefault())
1318 DstM.setDataLayout(SrcM->getDataLayout());
1319
1320 if (SrcM->getDataLayout() != DstM.getDataLayout()) {
1321 emitWarning("Linking two modules of different data layouts: '" +
1322 SrcM->getModuleIdentifier() + "' is '" +
1323 SrcM->getDataLayoutStr() + "' whereas '" +
1324 DstM.getModuleIdentifier() + "' is '" +
1325 DstM.getDataLayoutStr() + "'\n");
1326 }
1327
1328 // Copy the target triple from the source to dest if the dest's is empty.
1329 if (DstM.getTargetTriple().empty() && !SrcM->getTargetTriple().empty())
1330 DstM.setTargetTriple(SrcM->getTargetTriple());
1331
1332 Triple SrcTriple(SrcM->getTargetTriple()), DstTriple(DstM.getTargetTriple());
1333
1334 if (!SrcM->getTargetTriple().empty()&&
1335 !SrcTriple.isCompatibleWith(DstTriple))
1336 emitWarning("Linking two modules of different target triples: " +
1337 SrcM->getModuleIdentifier() + "' is '" +
1338 SrcM->getTargetTriple() + "' whereas '" +
1339 DstM.getModuleIdentifier() + "' is '" + DstM.getTargetTriple() +
1340 "'\n");
1341
1342 DstM.setTargetTriple(SrcTriple.merge(DstTriple));
1343
1344 // Append the module inline asm string.
1345 if (!IsPerformingImport && !SrcM->getModuleInlineAsm().empty()) {
1346 std::string SrcModuleInlineAsm = adjustInlineAsm(SrcM->getModuleInlineAsm(),
1347 SrcTriple);
1348 if (DstM.getModuleInlineAsm().empty())
1349 DstM.setModuleInlineAsm(SrcModuleInlineAsm);
1350 else
1351 DstM.setModuleInlineAsm(DstM.getModuleInlineAsm() + "\n" +
1352 SrcModuleInlineAsm);
1353 }
1354
1355 // Loop over all of the linked values to compute type mappings.
1356 computeTypeMapping();
1357
1358 std::reverse(Worklist.begin(), Worklist.end());
1359 while (!Worklist.empty()) {
1360 GlobalValue *GV = Worklist.back();
1361 Worklist.pop_back();
1362
1363 // Already mapped.
1364 if (ValueMap.find(GV) != ValueMap.end() ||
1365 AliasValueMap.find(GV) != AliasValueMap.end())
1366 continue;
1367
1368 assert(!GV->isDeclaration())((!GV->isDeclaration()) ? static_cast<void> (0) : __assert_fail
("!GV->isDeclaration()", "/build/llvm-toolchain-snapshot-8~svn350071/lib/Linker/IRMover.cpp"
, 1368, __PRETTY_FUNCTION__))
;
1369 Mapper.mapValue(*GV);
1370 if (FoundError)
1371 return std::move(*FoundError);
1372 }
1373
1374 // Note that we are done linking global value bodies. This prevents
1375 // metadata linking from creating new references.
1376 DoneLinkingBodies = true;
1377 Mapper.addFlags(RF_NullMapMissingGlobalValues);
1378
1379 // Remap all of the named MDNodes in Src into the DstM module. We do this
1380 // after linking GlobalValues so that MDNodes that reference GlobalValues
1381 // are properly remapped.
1382 linkNamedMDNodes();
1383
1384 // Merge the module flags into the DstM module.
1385 return linkModuleFlagsMetadata();
1386}
1387
1388IRMover::StructTypeKeyInfo::KeyTy::KeyTy(ArrayRef<Type *> E, bool P)
1389 : ETypes(E), IsPacked(P) {}
1390
1391IRMover::StructTypeKeyInfo::KeyTy::KeyTy(const StructType *ST)
1392 : ETypes(ST->elements()), IsPacked(ST->isPacked()) {}
1393
1394bool IRMover::StructTypeKeyInfo::KeyTy::operator==(const KeyTy &That) const {
1395 return IsPacked == That.IsPacked && ETypes == That.ETypes;
1396}
1397
1398bool IRMover::StructTypeKeyInfo::KeyTy::operator!=(const KeyTy &That) const {
1399 return !this->operator==(That);
1400}
1401
1402StructType *IRMover::StructTypeKeyInfo::getEmptyKey() {
1403 return DenseMapInfo<StructType *>::getEmptyKey();
1404}
1405
1406StructType *IRMover::StructTypeKeyInfo::getTombstoneKey() {
1407 return DenseMapInfo<StructType *>::getTombstoneKey();
1408}
1409
1410unsigned IRMover::StructTypeKeyInfo::getHashValue(const KeyTy &Key) {
1411 return hash_combine(hash_combine_range(Key.ETypes.begin(), Key.ETypes.end()),
1412 Key.IsPacked);
1413}
1414
1415unsigned IRMover::StructTypeKeyInfo::getHashValue(const StructType *ST) {
1416 return getHashValue(KeyTy(ST));
1417}
1418
1419bool IRMover::StructTypeKeyInfo::isEqual(const KeyTy &LHS,
1420 const StructType *RHS) {
1421 if (RHS == getEmptyKey() || RHS == getTombstoneKey())
1422 return false;
1423 return LHS == KeyTy(RHS);
1424}
1425
1426bool IRMover::StructTypeKeyInfo::isEqual(const StructType *LHS,
1427 const StructType *RHS) {
1428 if (RHS == getEmptyKey() || RHS == getTombstoneKey())
1429 return LHS == RHS;
1430 return KeyTy(LHS) == KeyTy(RHS);
1431}
1432
1433void IRMover::IdentifiedStructTypeSet::addNonOpaque(StructType *Ty) {
1434 assert(!Ty->isOpaque())((!Ty->isOpaque()) ? static_cast<void> (0) : __assert_fail
("!Ty->isOpaque()", "/build/llvm-toolchain-snapshot-8~svn350071/lib/Linker/IRMover.cpp"
, 1434, __PRETTY_FUNCTION__))
;
1435 NonOpaqueStructTypes.insert(Ty);
1436}
1437
1438void IRMover::IdentifiedStructTypeSet::switchToNonOpaque(StructType *Ty) {
1439 assert(!Ty->isOpaque())((!Ty->isOpaque()) ? static_cast<void> (0) : __assert_fail
("!Ty->isOpaque()", "/build/llvm-toolchain-snapshot-8~svn350071/lib/Linker/IRMover.cpp"
, 1439, __PRETTY_FUNCTION__))
;
1440 NonOpaqueStructTypes.insert(Ty);
1441 bool Removed = OpaqueStructTypes.erase(Ty);
1442 (void)Removed;
1443 assert(Removed)((Removed) ? static_cast<void> (0) : __assert_fail ("Removed"
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/Linker/IRMover.cpp"
, 1443, __PRETTY_FUNCTION__))
;
1444}
1445
1446void IRMover::IdentifiedStructTypeSet::addOpaque(StructType *Ty) {
1447 assert(Ty->isOpaque())((Ty->isOpaque()) ? static_cast<void> (0) : __assert_fail
("Ty->isOpaque()", "/build/llvm-toolchain-snapshot-8~svn350071/lib/Linker/IRMover.cpp"
, 1447, __PRETTY_FUNCTION__))
;
1448 OpaqueStructTypes.insert(Ty);
1449}
1450
1451StructType *
1452IRMover::IdentifiedStructTypeSet::findNonOpaque(ArrayRef<Type *> ETypes,
1453 bool IsPacked) {
1454 IRMover::StructTypeKeyInfo::KeyTy Key(ETypes, IsPacked);
1455 auto I = NonOpaqueStructTypes.find_as(Key);
1456 return I == NonOpaqueStructTypes.end() ? nullptr : *I;
1457}
1458
1459bool IRMover::IdentifiedStructTypeSet::hasType(StructType *Ty) {
1460 if (Ty->isOpaque())
1461 return OpaqueStructTypes.count(Ty);
1462 auto I = NonOpaqueStructTypes.find(Ty);
1463 return I == NonOpaqueStructTypes.end() ? false : *I == Ty;
1464}
1465
1466IRMover::IRMover(Module &M) : Composite(M) {
1467 TypeFinder StructTypes;
1468 StructTypes.run(M, /* OnlyNamed */ false);
1469 for (StructType *Ty : StructTypes) {
1470 if (Ty->isOpaque())
1471 IdentifiedStructTypes.addOpaque(Ty);
1472 else
1473 IdentifiedStructTypes.addNonOpaque(Ty);
1474 }
1475 // Self-map metadatas in the destination module. This is needed when
1476 // DebugTypeODRUniquing is enabled on the LLVMContext, since metadata in the
1477 // destination module may be reached from the source module.
1478 for (auto *MD : StructTypes.getVisitedMetadata()) {
1479 SharedMDs[MD].reset(const_cast<MDNode *>(MD));
1480 }
1481}
1482
1483Error IRMover::move(
1484 std::unique_ptr<Module> Src, ArrayRef<GlobalValue *> ValuesToLink,
1485 std::function<void(GlobalValue &, ValueAdder Add)> AddLazyFor,
1486 bool IsPerformingImport) {
1487 IRLinker TheIRLinker(Composite, SharedMDs, IdentifiedStructTypes,
1488 std::move(Src), ValuesToLink, std::move(AddLazyFor),
1489 IsPerformingImport);
1490 Error E = TheIRLinker.run();
1491 Composite.dropTriviallyDeadConstantArrays();
1492 return E;
1493}

/build/llvm-toolchain-snapshot-8~svn350071/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);
24
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)...));
20
Calling 'make_unique<llvm::StringError, const llvm::Twine &, std::error_code>'
22
Returned allocated memory
23
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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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~svn350071/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 function is compatible with the helpers from Support/WithColor.h. You
957/// can pass any of them as the OS. Please consider using them instead of
958/// including 'error: ' in the ErrorBanner.
959///
960/// This is useful in the base level of your program to allow clean termination
961/// (allowing clean deallocation of resources, etc.), while reporting error
962/// information to the user.
963void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner = {});
964
965/// Write all error messages (if any) in E to a string. The newline character
966/// is used to separate error messages.
967inline std::string toString(Error E) {
968 SmallVector<std::string, 2> Errors;
969 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
970 Errors.push_back(EI.message());
971 });
972 return join(Errors.begin(), Errors.end(), "\n");
973}
974
975/// Consume a Error without doing anything. This method should be used
976/// only where an error can be considered a reasonable and expected return
977/// value.
978///
979/// Uses of this method are potentially indicative of design problems: If it's
980/// legitimate to do nothing while processing an "error", the error-producer
981/// might be more clearly refactored to return an Optional<T>.
982inline void consumeError(Error Err) {
983 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
984}
985
986/// Helper for converting an Error to a bool.
987///
988/// This method returns true if Err is in an error state, or false if it is
989/// in a success state. Puts Err in a checked state in both cases (unlike
990/// Error::operator bool(), which only does this for success states).
991inline bool errorToBool(Error Err) {
992 bool IsError = static_cast<bool>(Err);
993 if (IsError)
994 consumeError(std::move(Err));
995 return IsError;
996}
997
998/// Helper for Errors used as out-parameters.
999///
1000/// This helper is for use with the Error-as-out-parameter idiom, where an error
1001/// is passed to a function or method by reference, rather than being returned.
1002/// In such cases it is helpful to set the checked bit on entry to the function
1003/// so that the error can be written to (unchecked Errors abort on assignment)
1004/// and clear the checked bit on exit so that clients cannot accidentally forget
1005/// to check the result. This helper performs these actions automatically using
1006/// RAII:
1007///
1008/// @code{.cpp}
1009/// Result foo(Error &Err) {
1010/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1011/// // <body of foo>
1012/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1013/// }
1014/// @endcode
1015///
1016/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1017/// used with optional Errors (Error pointers that are allowed to be null). If
1018/// ErrorAsOutParameter took an Error reference, an instance would have to be
1019/// created inside every condition that verified that Error was non-null. By
1020/// taking an Error pointer we can just create one instance at the top of the
1021/// function.
1022class ErrorAsOutParameter {
1023public:
1024 ErrorAsOutParameter(Error *Err) : Err(Err) {
1025 // Raise the checked bit if Err is success.
1026 if (Err)
1027 (void)!!*Err;
1028 }
1029
1030 ~ErrorAsOutParameter() {
1031 // Clear the checked bit.
1032 if (Err && !*Err)
1033 *Err = Error::success();
1034 }
1035
1036private:
1037 Error *Err;
1038};
1039
1040/// Helper for Expected<T>s used as out-parameters.
1041///
1042/// See ErrorAsOutParameter.
1043template <typename T>
1044class ExpectedAsOutParameter {
1045public:
1046 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1047 : ValOrErr(ValOrErr) {
1048 if (ValOrErr)
1049 (void)!!*ValOrErr;
1050 }
1051
1052 ~ExpectedAsOutParameter() {
1053 if (ValOrErr)
1054 ValOrErr->setUnchecked();
1055 }
1056
1057private:
1058 Expected<T> *ValOrErr;
1059};
1060
1061/// This class wraps a std::error_code in a Error.
1062///
1063/// This is useful if you're writing an interface that returns a Error
1064/// (or Expected) and you want to call code that still returns
1065/// std::error_codes.
1066class ECError : public ErrorInfo<ECError> {
1067 friend Error errorCodeToError(std::error_code);
1068
1069public:
1070 void setErrorCode(std::error_code EC) { this->EC = EC; }
1071 std::error_code convertToErrorCode() const override { return EC; }
1072 void log(raw_ostream &OS) const override { OS << EC.message(); }
1073
1074 // Used by ErrorInfo::classID.
1075 static char ID;
1076
1077protected:
1078 ECError() = default;
1079 ECError(std::error_code EC) : EC(EC) {}
1080
1081 std::error_code EC;
1082};
1083
1084/// The value returned by this function can be returned from convertToErrorCode
1085/// for Error values where no sensible translation to std::error_code exists.
1086/// It should only be used in this situation, and should never be used where a
1087/// sensible conversion to std::error_code is available, as attempts to convert
1088/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1089///error to try to convert such a value).
1090std::error_code inconvertibleErrorCode();
1091
1092/// Helper for converting an std::error_code to a Error.
1093Error errorCodeToError(std::error_code EC);
1094
1095/// Helper for converting an ECError to a std::error_code.
1096///
1097/// This method requires that Err be Error() or an ECError, otherwise it
1098/// will trigger a call to abort().
1099std::error_code errorToErrorCode(Error Err);
1100
1101/// Convert an ErrorOr<T> to an Expected<T>.
1102template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1103 if (auto EC = EO.getError())
1104 return errorCodeToError(EC);
1105 return std::move(*EO);
1106}
1107
1108/// Convert an Expected<T> to an ErrorOr<T>.
1109template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1110 if (auto Err = E.takeError())
1111 return errorToErrorCode(std::move(Err));
1112 return std::move(*E);
1113}
1114
1115/// This class wraps a string in an Error.
1116///
1117/// StringError is useful in cases where the client is not expected to be able
1118/// to consume the specific error message programmatically (for example, if the
1119/// error message is to be presented to the user).
1120///
1121/// StringError can also be used when additional information is to be printed
1122/// along with a error_code message. Depending on the constructor called, this
1123/// class can either display:
1124/// 1. the error_code message (ECError behavior)
1125/// 2. a string
1126/// 3. the error_code message and a string
1127///
1128/// These behaviors are useful when subtyping is required; for example, when a
1129/// specific library needs an explicit error type. In the example below,
1130/// PDBError is derived from StringError:
1131///
1132/// @code{.cpp}
1133/// Expected<int> foo() {
1134/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1135/// "Additional information");
1136/// }
1137/// @endcode
1138///
1139class StringError : public ErrorInfo<StringError> {
1140public:
1141 static char ID;
1142
1143 // Prints EC + S and converts to EC
1144 StringError(std::error_code EC, const Twine &S = Twine());
1145
1146 // Prints S and converts to EC
1147 StringError(const Twine &S, std::error_code EC);
1148
1149 void log(raw_ostream &OS) const override;
1150 std::error_code convertToErrorCode() const override;
1151
1152 const std::string &getMessage() const { return Msg; }
1153
1154private:
1155 std::string Msg;
1156 std::error_code EC;
1157 const bool PrintMsgOnly = false;
1158};
1159
1160/// Create formatted StringError object.
1161template <typename... Ts>
1162Error createStringError(std::error_code EC, char const *Fmt,
1163 const Ts &... Vals) {
1164 std::string Buffer;
1165 raw_string_ostream Stream(Buffer);
1166 Stream << format(Fmt, Vals...);
1167 return make_error<StringError>(Stream.str(), EC);
1168}
1169
1170Error createStringError(std::error_code EC, char const *Msg);
1171
1172/// This class wraps a filename and another Error.
1173///
1174/// In some cases, an error needs to live along a 'source' name, in order to
1175/// show more detailed information to the user.
1176class FileError final : public ErrorInfo<FileError> {
1177
1178 friend Error createFileError(std::string, Error);
1179
1180public:
1181 void log(raw_ostream &OS) const override {
1182 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~svn350071/include/llvm/Support/Error.h"
, 1182, __PRETTY_FUNCTION__))
;
1183 OS << "'" << FileName << "': ";
1184 Err->log(OS);
1185 }
1186
1187 Error takeError() { return Error(std::move(Err)); }
1188
1189 std::error_code convertToErrorCode() const override;
1190
1191 // Used by ErrorInfo::classID.
1192 static char ID;
1193
1194private:
1195 FileError(std::string F, std::unique_ptr<ErrorInfoBase> E) {
1196 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~svn350071/include/llvm/Support/Error.h"
, 1196, __PRETTY_FUNCTION__))
;
1197 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~svn350071/include/llvm/Support/Error.h"
, 1198, __PRETTY_FUNCTION__))
1198 "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~svn350071/include/llvm/Support/Error.h"
, 1198, __PRETTY_FUNCTION__))
;
1199 FileName = F;
1200 Err = std::move(E);
1201 }
1202
1203 static Error build(std::string F, Error E) {
1204 return Error(std::unique_ptr<FileError>(new FileError(F, E.takePayload())));
1205 }
1206
1207 std::string FileName;
1208 std::unique_ptr<ErrorInfoBase> Err;
1209};
1210
1211/// Concatenate a source file path and/or name with an Error. The resulting
1212/// Error is unchecked.
1213inline Error createFileError(std::string F, Error E) {
1214 return FileError::build(F, std::move(E));
1215}
1216
1217Error createFileError(std::string F, ErrorSuccess) = delete;
1218
1219/// Helper for check-and-exit error handling.
1220///
1221/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1222///
1223class ExitOnError {
1224public:
1225 /// Create an error on exit helper.
1226 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1227 : Banner(std::move(Banner)),
1228 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1229
1230 /// Set the banner string for any errors caught by operator().
1231 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1232
1233 /// Set the exit-code mapper function.
1234 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1235 this->GetExitCode = std::move(GetExitCode);
1236 }
1237
1238 /// Check Err. If it's in a failure state log the error(s) and exit.
1239 void operator()(Error Err) const { checkError(std::move(Err)); }
1240
1241 /// Check E. If it's in a success state then return the contained value. If
1242 /// it's in a failure state log the error(s) and exit.
1243 template <typename T> T operator()(Expected<T> &&E) const {
1244 checkError(E.takeError());
1245 return std::move(*E);
1246 }
1247
1248 /// Check E. If it's in a success state then return the contained reference. If
1249 /// it's in a failure state log the error(s) and exit.
1250 template <typename T> T& operator()(Expected<T&> &&E) const {
1251 checkError(E.takeError());
1252 return *E;
1253 }
1254
1255private:
1256 void checkError(Error Err) const {
1257 if (Err) {
1258 int ExitCode = GetExitCode(Err);
1259 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1260 exit(ExitCode);
1261 }
1262 }
1263
1264 std::string Banner;
1265 std::function<int(const Error &)> GetExitCode;
1266};
1267
1268/// Conversion from Error to LLVMErrorRef for C error bindings.
1269inline LLVMErrorRef wrap(Error Err) {
1270 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1271}
1272
1273/// Conversion from LLVMErrorRef to Error for C error bindings.
1274inline Error unwrap(LLVMErrorRef ErrRef) {
1275 return Error(std::unique_ptr<ErrorInfoBase>(
1276 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1277}
1278
1279} // end namespace llvm
1280
1281#endif // LLVM_SUPPORT_ERROR_H

/build/llvm-toolchain-snapshot-8~svn350071/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
74template <typename T> struct make_const_ptr {
75 using type =
76 typename std::add_pointer<typename std::add_const<T>::type>::type;
77};
78//===----------------------------------------------------------------------===//
79// Extra additions to <functional>
80//===----------------------------------------------------------------------===//
81
82template <class Ty> struct identity {
83 using argument_type = Ty;
84
85 Ty &operator()(Ty &self) const {
86 return self;
87 }
88 const Ty &operator()(const Ty &self) const {
89 return self;
90 }
91};
92
93template <class Ty> struct less_ptr {
94 bool operator()(const Ty* left, const Ty* right) const {
95 return *left < *right;
96 }
97};
98
99template <class Ty> struct greater_ptr {
100 bool operator()(const Ty* left, const Ty* right) const {
101 return *right < *left;
102 }
103};
104
105/// An efficient, type-erasing, non-owning reference to a callable. This is
106/// intended for use as the type of a function parameter that is not used
107/// after the function in question returns.
108///
109/// This class does not own the callable, so it is not in general safe to store
110/// a function_ref.
111template<typename Fn> class function_ref;
112
113template<typename Ret, typename ...Params>
114class function_ref<Ret(Params...)> {
115 Ret (*callback)(intptr_t callable, Params ...params) = nullptr;
116 intptr_t callable;
117
118 template<typename Callable>
119 static Ret callback_fn(intptr_t callable, Params ...params) {
120 return (*reinterpret_cast<Callable*>(callable))(
121 std::forward<Params>(params)...);
122 }
123
124public:
125 function_ref() = default;
126 function_ref(std::nullptr_t) {}
127
128 template <typename Callable>
129 function_ref(Callable &&callable,
130 typename std::enable_if<
131 !std::is_same<typename std::remove_reference<Callable>::type,
132 function_ref>::value>::type * = nullptr)
133 : callback(callback_fn<typename std::remove_reference<Callable>::type>),
134 callable(reinterpret_cast<intptr_t>(&callable)) {}
135
136 Ret operator()(Params ...params) const {
137 return callback(callable, std::forward<Params>(params)...);
138 }
139
140 operator bool() const { return callback; }
141};
142
143// deleter - Very very very simple method that is used to invoke operator
144// delete on something. It is used like this:
145//
146// for_each(V.begin(), B.end(), deleter<Interval>);
147template <class T>
148inline void deleter(T *Ptr) {
149 delete Ptr;
150}
151
152//===----------------------------------------------------------------------===//
153// Extra additions to <iterator>
154//===----------------------------------------------------------------------===//
155
156namespace adl_detail {
157
158using std::begin;
159
160template <typename ContainerTy>
161auto adl_begin(ContainerTy &&container)
162 -> decltype(begin(std::forward<ContainerTy>(container))) {
163 return begin(std::forward<ContainerTy>(container));
164}
165
166using std::end;
167
168template <typename ContainerTy>
169auto adl_end(ContainerTy &&container)
170 -> decltype(end(std::forward<ContainerTy>(container))) {
171 return end(std::forward<ContainerTy>(container));
172}
173
174using std::swap;
175
176template <typename T>
177void adl_swap(T &&lhs, T &&rhs) noexcept(noexcept(swap(std::declval<T>(),
178 std::declval<T>()))) {
179 swap(std::forward<T>(lhs), std::forward<T>(rhs));
180}
181
182} // end namespace adl_detail
183
184template <typename ContainerTy>
185auto adl_begin(ContainerTy &&container)
186 -> decltype(adl_detail::adl_begin(std::forward<ContainerTy>(container))) {
187 return adl_detail::adl_begin(std::forward<ContainerTy>(container));
188}
189
190template <typename ContainerTy>
191auto adl_end(ContainerTy &&container)
192 -> decltype(adl_detail::adl_end(std::forward<ContainerTy>(container))) {
193 return adl_detail::adl_end(std::forward<ContainerTy>(container));
194}
195
196template <typename T>
197void adl_swap(T &&lhs, T &&rhs) noexcept(
198 noexcept(adl_detail::adl_swap(std::declval<T>(), std::declval<T>()))) {
199 adl_detail::adl_swap(std::forward<T>(lhs), std::forward<T>(rhs));
200}
201
202/// Test whether \p RangeOrContainer is empty. Similar to C++17 std::empty.
203template <typename T>
204constexpr bool empty(const T &RangeOrContainer) {
205 return adl_begin(RangeOrContainer) == adl_end(RangeOrContainer);
206}
207
208// mapped_iterator - This is a simple iterator adapter that causes a function to
209// be applied whenever operator* is invoked on the iterator.
210
211template <typename ItTy, typename FuncTy,
212 typename FuncReturnTy =
213 decltype(std::declval<FuncTy>()(*std::declval<ItTy>()))>
214class mapped_iterator
215 : public iterator_adaptor_base<
216 mapped_iterator<ItTy, FuncTy>, ItTy,
217 typename std::iterator_traits<ItTy>::iterator_category,
218 typename std::remove_reference<FuncReturnTy>::type> {
219public:
220 mapped_iterator(ItTy U, FuncTy F)
221 : mapped_iterator::iterator_adaptor_base(std::move(U)), F(std::move(F)) {}
222
223 ItTy getCurrent() { return this->I; }
224
225 FuncReturnTy operator*() { return F(*this->I); }
226
227private:
228 FuncTy F;
229};
230
231// map_iterator - Provide a convenient way to create mapped_iterators, just like
232// make_pair is useful for creating pairs...
233template <class ItTy, class FuncTy>
234inline mapped_iterator<ItTy, FuncTy> map_iterator(ItTy I, FuncTy F) {
235 return mapped_iterator<ItTy, FuncTy>(std::move(I), std::move(F));
236}
237
238/// Helper to determine if type T has a member called rbegin().
239template <typename Ty> class has_rbegin_impl {
240 using yes = char[1];
241 using no = char[2];
242
243 template <typename Inner>
244 static yes& test(Inner *I, decltype(I->rbegin()) * = nullptr);
245
246 template <typename>
247 static no& test(...);
248
249public:
250 static const bool value = sizeof(test<Ty>(nullptr)) == sizeof(yes);
251};
252
253/// Metafunction to determine if T& or T has a member called rbegin().
254template <typename Ty>
255struct has_rbegin : has_rbegin_impl<typename std::remove_reference<Ty>::type> {
256};
257
258// Returns an iterator_range over the given container which iterates in reverse.
259// Note that the container must have rbegin()/rend() methods for this to work.
260template <typename ContainerTy>
261auto reverse(ContainerTy &&C,
262 typename std::enable_if<has_rbegin<ContainerTy>::value>::type * =
263 nullptr) -> decltype(make_range(C.rbegin(), C.rend())) {
264 return make_range(C.rbegin(), C.rend());
265}
266
267// Returns a std::reverse_iterator wrapped around the given iterator.
268template <typename IteratorTy>
269std::reverse_iterator<IteratorTy> make_reverse_iterator(IteratorTy It) {
270 return std::reverse_iterator<IteratorTy>(It);
271}
272
273// Returns an iterator_range over the given container which iterates in reverse.
274// Note that the container must have begin()/end() methods which return
275// bidirectional iterators for this to work.
276template <typename ContainerTy>
277auto reverse(
278 ContainerTy &&C,
279 typename std::enable_if<!has_rbegin<ContainerTy>::value>::type * = nullptr)
280 -> decltype(make_range(llvm::make_reverse_iterator(std::end(C)),
281 llvm::make_reverse_iterator(std::begin(C)))) {
282 return make_range(llvm::make_reverse_iterator(std::end(C)),
283 llvm::make_reverse_iterator(std::begin(C)));
284}
285
286/// An iterator adaptor that filters the elements of given inner iterators.
287///
288/// The predicate parameter should be a callable object that accepts the wrapped
289/// iterator's reference type and returns a bool. When incrementing or
290/// decrementing the iterator, it will call the predicate on each element and
291/// skip any where it returns false.
292///
293/// \code
294/// int A[] = { 1, 2, 3, 4 };
295/// auto R = make_filter_range(A, [](int N) { return N % 2 == 1; });
296/// // R contains { 1, 3 }.
297/// \endcode
298///
299/// Note: filter_iterator_base implements support for forward iteration.
300/// filter_iterator_impl exists to provide support for bidirectional iteration,
301/// conditional on whether the wrapped iterator supports it.
302template <typename WrappedIteratorT, typename PredicateT, typename IterTag>
303class filter_iterator_base
304 : public iterator_adaptor_base<
305 filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
306 WrappedIteratorT,
307 typename std::common_type<
308 IterTag, typename std::iterator_traits<
309 WrappedIteratorT>::iterator_category>::type> {
310 using BaseT = iterator_adaptor_base<
311 filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
312 WrappedIteratorT,
313 typename std::common_type<
314 IterTag, typename std::iterator_traits<
315 WrappedIteratorT>::iterator_category>::type>;
316
317protected:
318 WrappedIteratorT End;
319 PredicateT Pred;
320
321 void findNextValid() {
322 while (this->I != End && !Pred(*this->I))
323 BaseT::operator++();
324 }
325
326 // Construct the iterator. The begin iterator needs to know where the end
327 // is, so that it can properly stop when it gets there. The end iterator only
328 // needs the predicate to support bidirectional iteration.
329 filter_iterator_base(WrappedIteratorT Begin, WrappedIteratorT End,
330 PredicateT Pred)
331 : BaseT(Begin), End(End), Pred(Pred) {
332 findNextValid();
333 }
334
335public:
336 using BaseT::operator++;
337
338 filter_iterator_base &operator++() {
339 BaseT::operator++();
340 findNextValid();
341 return *this;
342 }
343};
344
345/// Specialization of filter_iterator_base for forward iteration only.
346template <typename WrappedIteratorT, typename PredicateT,
347 typename IterTag = std::forward_iterator_tag>
348class filter_iterator_impl
349 : public filter_iterator_base<WrappedIteratorT, PredicateT, IterTag> {
350 using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>;
351
352public:
353 filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
354 PredicateT Pred)
355 : BaseT(Begin, End, Pred) {}
356};
357
358/// Specialization of filter_iterator_base for bidirectional iteration.
359template <typename WrappedIteratorT, typename PredicateT>
360class filter_iterator_impl<WrappedIteratorT, PredicateT,
361 std::bidirectional_iterator_tag>
362 : public filter_iterator_base<WrappedIteratorT, PredicateT,
363 std::bidirectional_iterator_tag> {
364 using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT,
365 std::bidirectional_iterator_tag>;
366 void findPrevValid() {
367 while (!this->Pred(*this->I))
368 BaseT::operator--();
369 }
370
371public:
372 using BaseT::operator--;
373
374 filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
375 PredicateT Pred)
376 : BaseT(Begin, End, Pred) {}
377
378 filter_iterator_impl &operator--() {
379 BaseT::operator--();
380 findPrevValid();
381 return *this;
382 }
383};
384
385namespace detail {
386
387template <bool is_bidirectional> struct fwd_or_bidi_tag_impl {
388 using type = std::forward_iterator_tag;
389};
390
391template <> struct fwd_or_bidi_tag_impl<true> {
392 using type = std::bidirectional_iterator_tag;
393};
394
395/// Helper which sets its type member to forward_iterator_tag if the category
396/// of \p IterT does not derive from bidirectional_iterator_tag, and to
397/// bidirectional_iterator_tag otherwise.
398template <typename IterT> struct fwd_or_bidi_tag {
399 using type = typename fwd_or_bidi_tag_impl<std::is_base_of<
400 std::bidirectional_iterator_tag,
401 typename std::iterator_traits<IterT>::iterator_category>::value>::type;
402};
403
404} // namespace detail
405
406/// Defines filter_iterator to a suitable specialization of
407/// filter_iterator_impl, based on the underlying iterator's category.
408template <typename WrappedIteratorT, typename PredicateT>
409using filter_iterator = filter_iterator_impl<
410 WrappedIteratorT, PredicateT,
411 typename detail::fwd_or_bidi_tag<WrappedIteratorT>::type>;
412
413/// Convenience function that takes a range of elements and a predicate,
414/// and return a new filter_iterator range.
415///
416/// FIXME: Currently if RangeT && is a rvalue reference to a temporary, the
417/// lifetime of that temporary is not kept by the returned range object, and the
418/// temporary is going to be dropped on the floor after the make_iterator_range
419/// full expression that contains this function call.
420template <typename RangeT, typename PredicateT>
421iterator_range<filter_iterator<detail::IterOfRange<RangeT>, PredicateT>>
422make_filter_range(RangeT &&Range, PredicateT Pred) {
423 using FilterIteratorT =
424 filter_iterator<detail::IterOfRange<RangeT>, PredicateT>;
425 return make_range(
426 FilterIteratorT(std::begin(std::forward<RangeT>(Range)),
427 std::end(std::forward<RangeT>(Range)), Pred),
428 FilterIteratorT(std::end(std::forward<RangeT>(Range)),
429 std::end(std::forward<RangeT>(Range)), Pred));
430}
431
432/// A pseudo-iterator adaptor that is designed to implement "early increment"
433/// style loops.
434///
435/// This is *not a normal iterator* and should almost never be used directly. It
436/// is intended primarily to be used with range based for loops and some range
437/// algorithms.
438///
439/// The iterator isn't quite an `OutputIterator` or an `InputIterator` but
440/// somewhere between them. The constraints of these iterators are:
441///
442/// - On construction or after being incremented, it is comparable and
443/// dereferencable. It is *not* incrementable.
444/// - After being dereferenced, it is neither comparable nor dereferencable, it
445/// is only incrementable.
446///
447/// This means you can only dereference the iterator once, and you can only
448/// increment it once between dereferences.
449template <typename WrappedIteratorT>
450class early_inc_iterator_impl
451 : public iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
452 WrappedIteratorT, std::input_iterator_tag> {
453 using BaseT =
454 iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
455 WrappedIteratorT, std::input_iterator_tag>;
456
457 using PointerT = typename std::iterator_traits<WrappedIteratorT>::pointer;
458
459protected:
460#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
461 bool IsEarlyIncremented = false;
462#endif
463
464public:
465 early_inc_iterator_impl(WrappedIteratorT I) : BaseT(I) {}
466
467 using BaseT::operator*;
468 typename BaseT::reference operator*() {
469#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
470 assert(!IsEarlyIncremented && "Cannot dereference twice!")((!IsEarlyIncremented && "Cannot dereference twice!")
? static_cast<void> (0) : __assert_fail ("!IsEarlyIncremented && \"Cannot dereference twice!\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/ADT/STLExtras.h"
, 470, __PRETTY_FUNCTION__))
;
471 IsEarlyIncremented = true;
472#endif
473 return *(this->I)++;
474 }
475
476 using BaseT::operator++;
477 early_inc_iterator_impl &operator++() {
478#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
479 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~svn350071/include/llvm/ADT/STLExtras.h"
, 479, __PRETTY_FUNCTION__))
;
480 IsEarlyIncremented = false;
481#endif
482 return *this;
483 }
484
485 using BaseT::operator==;
486 bool operator==(const early_inc_iterator_impl &RHS) const {
487#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
488 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~svn350071/include/llvm/ADT/STLExtras.h"
, 488, __PRETTY_FUNCTION__))
;
489#endif
490 return BaseT::operator==(RHS);
491 }
492};
493
494/// Make a range that does early increment to allow mutation of the underlying
495/// range without disrupting iteration.
496///
497/// The underlying iterator will be incremented immediately after it is
498/// dereferenced, allowing deletion of the current node or insertion of nodes to
499/// not disrupt iteration provided they do not invalidate the *next* iterator --
500/// the current iterator can be invalidated.
501///
502/// This requires a very exact pattern of use that is only really suitable to
503/// range based for loops and other range algorithms that explicitly guarantee
504/// to dereference exactly once each element, and to increment exactly once each
505/// element.
506template <typename RangeT>
507iterator_range<early_inc_iterator_impl<detail::IterOfRange<RangeT>>>
508make_early_inc_range(RangeT &&Range) {
509 using EarlyIncIteratorT =
510 early_inc_iterator_impl<detail::IterOfRange<RangeT>>;
511 return make_range(EarlyIncIteratorT(std::begin(std::forward<RangeT>(Range))),
512 EarlyIncIteratorT(std::end(std::forward<RangeT>(Range))));
513}
514
515// forward declarations required by zip_shortest/zip_first/zip_longest
516template <typename R, typename UnaryPredicate>
517bool all_of(R &&range, UnaryPredicate P);
518template <typename R, typename UnaryPredicate>
519bool any_of(R &&range, UnaryPredicate P);
520
521template <size_t... I> struct index_sequence;
522
523template <class... Ts> struct index_sequence_for;
524
525namespace detail {
526
527using std::declval;
528
529// We have to alias this since inlining the actual type at the usage site
530// in the parameter list of iterator_facade_base<> below ICEs MSVC 2017.
531template<typename... Iters> struct ZipTupleType {
532 using type = std::tuple<decltype(*declval<Iters>())...>;
533};
534
535template <typename ZipType, typename... Iters>
536using zip_traits = iterator_facade_base<
537 ZipType, typename std::common_type<std::bidirectional_iterator_tag,
538 typename std::iterator_traits<
539 Iters>::iterator_category...>::type,
540 // ^ TODO: Implement random access methods.
541 typename ZipTupleType<Iters...>::type,
542 typename std::iterator_traits<typename std::tuple_element<
543 0, std::tuple<Iters...>>::type>::difference_type,
544 // ^ FIXME: This follows boost::make_zip_iterator's assumption that all
545 // inner iterators have the same difference_type. It would fail if, for
546 // instance, the second field's difference_type were non-numeric while the
547 // first is.
548 typename ZipTupleType<Iters...>::type *,
549 typename ZipTupleType<Iters...>::type>;
550
551template <typename ZipType, typename... Iters>
552struct zip_common : public zip_traits<ZipType, Iters...> {
553 using Base = zip_traits<ZipType, Iters...>;
554 using value_type = typename Base::value_type;
555
556 std::tuple<Iters...> iterators;
557
558protected:
559 template <size_t... Ns> value_type deref(index_sequence<Ns...>) const {
560 return value_type(*std::get<Ns>(iterators)...);
561 }
562
563 template <size_t... Ns>
564 decltype(iterators) tup_inc(index_sequence<Ns...>) const {
565 return std::tuple<Iters...>(std::next(std::get<Ns>(iterators))...);
566 }
567
568 template <size_t... Ns>
569 decltype(iterators) tup_dec(index_sequence<Ns...>) const {
570 return std::tuple<Iters...>(std::prev(std::get<Ns>(iterators))...);
571 }
572
573public:
574 zip_common(Iters &&... ts) : iterators(std::forward<Iters>(ts)...) {}
575
576 value_type operator*() { return deref(index_sequence_for<Iters...>{}); }
577
578 const value_type operator*() const {
579 return deref(index_sequence_for<Iters...>{});
580 }
581
582 ZipType &operator++() {
583 iterators = tup_inc(index_sequence_for<Iters...>{});
584 return *reinterpret_cast<ZipType *>(this);
585 }
586
587 ZipType &operator--() {
588 static_assert(Base::IsBidirectional,
589 "All inner iterators must be at least bidirectional.");
590 iterators = tup_dec(index_sequence_for<Iters...>{});
591 return *reinterpret_cast<ZipType *>(this);
592 }
593};
594
595template <typename... Iters>
596struct zip_first : public zip_common<zip_first<Iters...>, Iters...> {
597 using Base = zip_common<zip_first<Iters...>, Iters...>;
598
599 bool operator==(const zip_first<Iters...> &other) const {
600 return std::get<0>(this->iterators) == std::get<0>(other.iterators);
601 }
602
603 zip_first(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
604};
605
606template <typename... Iters>
607class zip_shortest : public zip_common<zip_shortest<Iters...>, Iters...> {
608 template <size_t... Ns>
609 bool test(const zip_shortest<Iters...> &other, index_sequence<Ns...>) const {
610 return all_of(std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
611 std::get<Ns>(other.iterators)...},
612 identity<bool>{});
613 }
614
615public:
616 using Base = zip_common<zip_shortest<Iters...>, Iters...>;
617
618 zip_shortest(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
619
620 bool operator==(const zip_shortest<Iters...> &other) const {
621 return !test(other, index_sequence_for<Iters...>{});
622 }
623};
624
625template <template <typename...> class ItType, typename... Args> class zippy {
626public:
627 using iterator = ItType<decltype(std::begin(std::declval<Args>()))...>;
628 using iterator_category = typename iterator::iterator_category;
629 using value_type = typename iterator::value_type;
630 using difference_type = typename iterator::difference_type;
631 using pointer = typename iterator::pointer;
632 using reference = typename iterator::reference;
633
634private:
635 std::tuple<Args...> ts;
636
637 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) const {
638 return iterator(std::begin(std::get<Ns>(ts))...);
639 }
640 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) const {
641 return iterator(std::end(std::get<Ns>(ts))...);
642 }
643
644public:
645 zippy(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
646
647 iterator begin() const { return begin_impl(index_sequence_for<Args...>{}); }
648 iterator end() const { return end_impl(index_sequence_for<Args...>{}); }
649};
650
651} // end namespace detail
652
653/// zip iterator for two or more iteratable types.
654template <typename T, typename U, typename... Args>
655detail::zippy<detail::zip_shortest, T, U, Args...> zip(T &&t, U &&u,
656 Args &&... args) {
657 return detail::zippy<detail::zip_shortest, T, U, Args...>(
658 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
659}
660
661/// zip iterator that, for the sake of efficiency, assumes the first iteratee to
662/// be the shortest.
663template <typename T, typename U, typename... Args>
664detail::zippy<detail::zip_first, T, U, Args...> zip_first(T &&t, U &&u,
665 Args &&... args) {
666 return detail::zippy<detail::zip_first, T, U, Args...>(
667 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
668}
669
670namespace detail {
671template <typename Iter>
672static Iter next_or_end(const Iter &I, const Iter &End) {
673 if (I == End)
674 return End;
675 return std::next(I);
676}
677
678template <typename Iter>
679static auto deref_or_none(const Iter &I, const Iter &End)
680 -> llvm::Optional<typename std::remove_const<
681 typename std::remove_reference<decltype(*I)>::type>::type> {
682 if (I == End)
683 return None;
684 return *I;
685}
686
687template <typename Iter> struct ZipLongestItemType {
688 using type =
689 llvm::Optional<typename std::remove_const<typename std::remove_reference<
690 decltype(*std::declval<Iter>())>::type>::type>;
691};
692
693template <typename... Iters> struct ZipLongestTupleType {
694 using type = std::tuple<typename ZipLongestItemType<Iters>::type...>;
695};
696
697template <typename... Iters>
698class zip_longest_iterator
699 : public iterator_facade_base<
700 zip_longest_iterator<Iters...>,
701 typename std::common_type<
702 std::forward_iterator_tag,
703 typename std::iterator_traits<Iters>::iterator_category...>::type,
704 typename ZipLongestTupleType<Iters...>::type,
705 typename std::iterator_traits<typename std::tuple_element<
706 0, std::tuple<Iters...>>::type>::difference_type,
707 typename ZipLongestTupleType<Iters...>::type *,
708 typename ZipLongestTupleType<Iters...>::type> {
709public:
710 using value_type = typename ZipLongestTupleType<Iters...>::type;
711
712private:
713 std::tuple<Iters...> iterators;
714 std::tuple<Iters...> end_iterators;
715
716 template <size_t... Ns>
717 bool test(const zip_longest_iterator<Iters...> &other,
718 index_sequence<Ns...>) const {
719 return llvm::any_of(
720 std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
721 std::get<Ns>(other.iterators)...},
722 identity<bool>{});
723 }
724
725 template <size_t... Ns> value_type deref(index_sequence<Ns...>) const {
726 return value_type(
727 deref_or_none(std::get<Ns>(iterators), std::get<Ns>(end_iterators))...);
728 }
729
730 template <size_t... Ns>
731 decltype(iterators) tup_inc(index_sequence<Ns...>) const {
732 return std::tuple<Iters...>(
733 next_or_end(std::get<Ns>(iterators), std::get<Ns>(end_iterators))...);
734 }
735
736public:
737 zip_longest_iterator(std::pair<Iters &&, Iters &&>... ts)
738 : iterators(std::forward<Iters>(ts.first)...),
739 end_iterators(std::forward<Iters>(ts.second)...) {}
740
741 value_type operator*() { return deref(index_sequence_for<Iters...>{}); }
742
743 value_type operator*() const { return deref(index_sequence_for<Iters...>{}); }
744
745 zip_longest_iterator<Iters...> &operator++() {
746 iterators = tup_inc(index_sequence_for<Iters...>{});
747 return *this;
748 }
749
750 bool operator==(const zip_longest_iterator<Iters...> &other) const {
751 return !test(other, index_sequence_for<Iters...>{});
752 }
753};
754
755template <typename... Args> class zip_longest_range {
756public:
757 using iterator =
758 zip_longest_iterator<decltype(adl_begin(std::declval<Args>()))...>;
759 using iterator_category = typename iterator::iterator_category;
760 using value_type = typename iterator::value_type;
761 using difference_type = typename iterator::difference_type;
762 using pointer = typename iterator::pointer;
763 using reference = typename iterator::reference;
764
765private:
766 std::tuple<Args...> ts;
767
768 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) const {
769 return iterator(std::make_pair(adl_begin(std::get<Ns>(ts)),
770 adl_end(std::get<Ns>(ts)))...);
771 }
772
773 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) const {
774 return iterator(std::make_pair(adl_end(std::get<Ns>(ts)),
775 adl_end(std::get<Ns>(ts)))...);
776 }
777
778public:
779 zip_longest_range(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
780
781 iterator begin() const { return begin_impl(index_sequence_for<Args...>{}); }
782 iterator end() const { return end_impl(index_sequence_for<Args...>{}); }
783};
784} // namespace detail
785
786/// Iterate over two or more iterators at the same time. Iteration continues
787/// until all iterators reach the end. The llvm::Optional only contains a value
788/// if the iterator has not reached the end.
789template <typename T, typename U, typename... Args>
790detail::zip_longest_range<T, U, Args...> zip_longest(T &&t, U &&u,
791 Args &&... args) {
792 return detail::zip_longest_range<T, U, Args...>(
793 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
794}
795
796/// Iterator wrapper that concatenates sequences together.
797///
798/// This can concatenate different iterators, even with different types, into
799/// a single iterator provided the value types of all the concatenated
800/// iterators expose `reference` and `pointer` types that can be converted to
801/// `ValueT &` and `ValueT *` respectively. It doesn't support more
802/// interesting/customized pointer or reference types.
803///
804/// Currently this only supports forward or higher iterator categories as
805/// inputs and always exposes a forward iterator interface.
806template <typename ValueT, typename... IterTs>
807class concat_iterator
808 : public iterator_facade_base<concat_iterator<ValueT, IterTs...>,
809 std::forward_iterator_tag, ValueT> {
810 using BaseT = typename concat_iterator::iterator_facade_base;
811
812 /// We store both the current and end iterators for each concatenated
813 /// sequence in a tuple of pairs.
814 ///
815 /// Note that something like iterator_range seems nice at first here, but the
816 /// range properties are of little benefit and end up getting in the way
817 /// because we need to do mutation on the current iterators.
818 std::tuple<IterTs...> Begins;
819 std::tuple<IterTs...> Ends;
820
821 /// Attempts to increment a specific iterator.
822 ///
823 /// Returns true if it was able to increment the iterator. Returns false if
824 /// the iterator is already at the end iterator.
825 template <size_t Index> bool incrementHelper() {
826 auto &Begin = std::get<Index>(Begins);
827 auto &End = std::get<Index>(Ends);
828 if (Begin == End)
829 return false;
830
831 ++Begin;
832 return true;
833 }
834
835 /// Increments the first non-end iterator.
836 ///
837 /// It is an error to call this with all iterators at the end.
838 template <size_t... Ns> void increment(index_sequence<Ns...>) {
839 // Build a sequence of functions to increment each iterator if possible.
840 bool (concat_iterator::*IncrementHelperFns[])() = {
841 &concat_iterator::incrementHelper<Ns>...};
842
843 // Loop over them, and stop as soon as we succeed at incrementing one.
844 for (auto &IncrementHelperFn : IncrementHelperFns)
845 if ((this->*IncrementHelperFn)())
846 return;
847
848 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~svn350071/include/llvm/ADT/STLExtras.h"
, 848)
;
849 }
850
851 /// Returns null if the specified iterator is at the end. Otherwise,
852 /// dereferences the iterator and returns the address of the resulting
853 /// reference.
854 template <size_t Index> ValueT *getHelper() const {
855 auto &Begin = std::get<Index>(Begins);
856 auto &End = std::get<Index>(Ends);
857 if (Begin == End)
858 return nullptr;
859
860 return &*Begin;
861 }
862
863 /// Finds the first non-end iterator, dereferences, and returns the resulting
864 /// reference.
865 ///
866 /// It is an error to call this with all iterators at the end.
867 template <size_t... Ns> ValueT &get(index_sequence<Ns...>) const {
868 // Build a sequence of functions to get from iterator if possible.
869 ValueT *(concat_iterator::*GetHelperFns[])() const = {
870 &concat_iterator::getHelper<Ns>...};
871
872 // Loop over them, and return the first result we find.
873 for (auto &GetHelperFn : GetHelperFns)
874 if (ValueT *P = (this->*GetHelperFn)())
875 return *P;
876
877 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~svn350071/include/llvm/ADT/STLExtras.h"
, 877)
;
878 }
879
880public:
881 /// Constructs an iterator from a squence of ranges.
882 ///
883 /// We need the full range to know how to switch between each of the
884 /// iterators.
885 template <typename... RangeTs>
886 explicit concat_iterator(RangeTs &&... Ranges)
887 : Begins(std::begin(Ranges)...), Ends(std::end(Ranges)...) {}
888
889 using BaseT::operator++;
890
891 concat_iterator &operator++() {
892 increment(index_sequence_for<IterTs...>());
893 return *this;
894 }
895
896 ValueT &operator*() const { return get(index_sequence_for<IterTs...>()); }
897
898 bool operator==(const concat_iterator &RHS) const {
899 return Begins == RHS.Begins && Ends == RHS.Ends;
900 }
901};
902
903namespace detail {
904
905/// Helper to store a sequence of ranges being concatenated and access them.
906///
907/// This is designed to facilitate providing actual storage when temporaries
908/// are passed into the constructor such that we can use it as part of range
909/// based for loops.
910template <typename ValueT, typename... RangeTs> class concat_range {
911public:
912 using iterator =
913 concat_iterator<ValueT,
914 decltype(std::begin(std::declval<RangeTs &>()))...>;
915
916private:
917 std::tuple<RangeTs...> Ranges;
918
919 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) {
920 return iterator(std::get<Ns>(Ranges)...);
921 }
922 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) {
923 return iterator(make_range(std::end(std::get<Ns>(Ranges)),
924 std::end(std::get<Ns>(Ranges)))...);
925 }
926
927public:
928 concat_range(RangeTs &&... Ranges)
929 : Ranges(std::forward<RangeTs>(Ranges)...) {}
930
931 iterator begin() { return begin_impl(index_sequence_for<RangeTs...>{}); }
932 iterator end() { return end_impl(index_sequence_for<RangeTs...>{}); }
933};
934
935} // end namespace detail
936
937/// Concatenated range across two or more ranges.
938///
939/// The desired value type must be explicitly specified.
940template <typename ValueT, typename... RangeTs>
941detail::concat_range<ValueT, RangeTs...> concat(RangeTs &&... Ranges) {
942 static_assert(sizeof...(RangeTs) > 1,
943 "Need more than one range to concatenate!");
944 return detail::concat_range<ValueT, RangeTs...>(
945 std::forward<RangeTs>(Ranges)...);
946}
947
948//===----------------------------------------------------------------------===//
949// Extra additions to <utility>
950//===----------------------------------------------------------------------===//
951
952/// Function object to check whether the first component of a std::pair
953/// compares less than the first component of another std::pair.
954struct less_first {
955 template <typename T> bool operator()(const T &lhs, const T &rhs) const {
956 return lhs.first < rhs.first;
957 }
958};
959
960/// Function object to check whether the second component of a std::pair
961/// compares less than the second component of another std::pair.
962struct less_second {
963 template <typename T> bool operator()(const T &lhs, const T &rhs) const {
964 return lhs.second < rhs.second;
965 }
966};
967
968/// \brief Function object to apply a binary function to the first component of
969/// a std::pair.
970template<typename FuncTy>
971struct on_first {
972 FuncTy func;
973
974 template <typename T>
975 auto operator()(const T &lhs, const T &rhs) const
976 -> decltype(func(lhs.first, rhs.first)) {
977 return func(lhs.first, rhs.first);
978 }
979};
980
981// A subset of N3658. More stuff can be added as-needed.
982
983/// Represents a compile-time sequence of integers.
984template <class T, T... I> struct integer_sequence {
985 using value_type = T;
986
987 static constexpr size_t size() { return sizeof...(I); }
988};
989
990/// Alias for the common case of a sequence of size_ts.
991template <size_t... I>
992struct index_sequence : integer_sequence<std::size_t, I...> {};
993
994template <std::size_t N, std::size_t... I>
995struct build_index_impl : build_index_impl<N - 1, N - 1, I...> {};
996template <std::size_t... I>
997struct build_index_impl<0, I...> : index_sequence<I...> {};
998
999/// Creates a compile-time integer sequence for a parameter pack.
1000template <class... Ts>
1001struct index_sequence_for : build_index_impl<sizeof...(Ts)> {};
1002
1003/// Utility type to build an inheritance chain that makes it easy to rank
1004/// overload candidates.
1005template <int N> struct rank : rank<N - 1> {};
1006template <> struct rank<0> {};
1007
1008/// traits class for checking whether type T is one of any of the given
1009/// types in the variadic list.
1010template <typename T, typename... Ts> struct is_one_of {
1011 static const bool value = false;
1012};
1013
1014template <typename T, typename U, typename... Ts>
1015struct is_one_of<T, U, Ts...> {
1016 static const bool value =
1017 std::is_same<T, U>::value || is_one_of<T, Ts...>::value;
1018};
1019
1020/// traits class for checking whether type T is a base class for all
1021/// the given types in the variadic list.
1022template <typename T, typename... Ts> struct are_base_of {
1023 static const bool value = true;
1024};
1025
1026template <typename T, typename U, typename... Ts>
1027struct are_base_of<T, U, Ts...> {
1028 static const bool value =
1029 std::is_base_of<T, U>::value && are_base_of<T, Ts...>::value;
1030};
1031
1032//===----------------------------------------------------------------------===//
1033// Extra additions for arrays
1034//===----------------------------------------------------------------------===//
1035
1036/// Find the length of an array.
1037template <class T, std::size_t N>
1038constexpr inline size_t array_lengthof(T (&)[N]) {
1039 return N;
1040}
1041
1042/// Adapt std::less<T> for array_pod_sort.
1043template<typename T>
1044inline int array_pod_sort_comparator(const void *P1, const void *P2) {
1045 if (std::less<T>()(*reinterpret_cast<const T*>(P1),
1046 *reinterpret_cast<const T*>(P2)))
1047 return -1;
1048 if (std::less<T>()(*reinterpret_cast<const T*>(P2),
1049 *reinterpret_cast<const T*>(P1)))
1050 return 1;
1051 return 0;
1052}
1053
1054/// get_array_pod_sort_comparator - This is an internal helper function used to
1055/// get type deduction of T right.
1056template<typename T>
1057inline int (*get_array_pod_sort_comparator(const T &))
1058 (const void*, const void*) {
1059 return array_pod_sort_comparator<T>;
1060}
1061
1062/// array_pod_sort - This sorts an array with the specified start and end
1063/// extent. This is just like std::sort, except that it calls qsort instead of
1064/// using an inlined template. qsort is slightly slower than std::sort, but
1065/// most sorts are not performance critical in LLVM and std::sort has to be
1066/// template instantiated for each type, leading to significant measured code
1067/// bloat. This function should generally be used instead of std::sort where
1068/// possible.
1069///
1070/// This function assumes that you have simple POD-like types that can be
1071/// compared with std::less and can be moved with memcpy. If this isn't true,
1072/// you should use std::sort.
1073///
1074/// NOTE: If qsort_r were portable, we could allow a custom comparator and
1075/// default to std::less.
1076template<class IteratorTy>
1077inline void array_pod_sort(IteratorTy Start, IteratorTy End) {
1078 // Don't inefficiently call qsort with one element or trigger undefined
1079 // behavior with an empty sequence.
1080 auto NElts = End - Start;
1081 if (NElts <= 1) return;
1082#ifdef EXPENSIVE_CHECKS
1083 std::mt19937 Generator(std::random_device{}());
1084 std::shuffle(Start, End, Generator);
1085#endif
1086 qsort(&*Start, NElts, sizeof(*Start), get_array_pod_sort_comparator(*Start));
1087}
1088
1089template <class IteratorTy>
1090inline void array_pod_sort(
1091 IteratorTy Start, IteratorTy End,
1092 int (*Compare)(
1093 const typename std::iterator_traits<IteratorTy>::value_type *,
1094 const typename std::iterator_traits<IteratorTy>::value_type *)) {
1095 // Don't inefficiently call qsort with one element or trigger undefined
1096 // behavior with an empty sequence.
1097 auto NElts = End - Start;
1098 if (NElts <= 1) return;
1099#ifdef EXPENSIVE_CHECKS
1100 std::mt19937 Generator(std::random_device{}());
1101 std::shuffle(Start, End, Generator);
1102#endif
1103 qsort(&*Start, NElts, sizeof(*Start),
1104 reinterpret_cast<int (*)(const void *, const void *)>(Compare));
1105}
1106
1107// Provide wrappers to std::sort which shuffle the elements before sorting
1108// to help uncover non-deterministic behavior (PR35135).
1109template <typename IteratorTy>
1110inline void sort(IteratorTy Start, IteratorTy End) {
1111#ifdef EXPENSIVE_CHECKS
1112 std::mt19937 Generator(std::random_device{}());
1113 std::shuffle(Start, End, Generator);
1114#endif
1115 std::sort(Start, End);
1116}
1117
1118template <typename Container> inline void sort(Container &&C) {
1119 llvm::sort(adl_begin(C), adl_end(C));
1120}
1121
1122template <typename IteratorTy, typename Compare>
1123inline void sort(IteratorTy Start, IteratorTy End, Compare Comp) {
1124#ifdef EXPENSIVE_CHECKS
1125 std::mt19937 Generator(std::random_device{}());
1126 std::shuffle(Start, End, Generator);
1127#endif
1128 std::sort(Start, End, Comp);
1129}
1130
1131template <typename Container, typename Compare>
1132inline void sort(Container &&C, Compare Comp) {
1133 llvm::sort(adl_begin(C), adl_end(C), Comp);
1134}
1135
1136//===----------------------------------------------------------------------===//
1137// Extra additions to <algorithm>
1138//===----------------------------------------------------------------------===//
1139
1140/// For a container of pointers, deletes the pointers and then clears the
1141/// container.
1142template<typename Container>
1143void DeleteContainerPointers(Container &C) {
1144 for (auto V : C)
1145 delete V;
1146 C.clear();
1147}
1148
1149/// In a container of pairs (usually a map) whose second element is a pointer,
1150/// deletes the second elements and then clears the container.
1151template<typename Container>
1152void DeleteContainerSeconds(Container &C) {
1153 for (auto &V : C)
1154 delete V.second;
1155 C.clear();
1156}
1157
1158/// Get the size of a range. This is a wrapper function around std::distance
1159/// which is only enabled when the operation is O(1).
1160template <typename R>
1161auto size(R &&Range, typename std::enable_if<
1162 std::is_same<typename std::iterator_traits<decltype(
1163 Range.begin())>::iterator_category,
1164 std::random_access_iterator_tag>::value,
1165 void>::type * = nullptr)
1166 -> decltype(std::distance(Range.begin(), Range.end())) {
1167 return std::distance(Range.begin(), Range.end());
1168}
1169
1170/// Provide wrappers to std::for_each which take ranges instead of having to
1171/// pass begin/end explicitly.
1172template <typename R, typename UnaryPredicate>
1173UnaryPredicate for_each(R &&Range, UnaryPredicate P) {
1174 return std::for_each(adl_begin(Range), adl_end(Range), P);
1175}
1176
1177/// Provide wrappers to std::all_of which take ranges instead of having to pass
1178/// begin/end explicitly.
1179template <typename R, typename UnaryPredicate>
1180bool all_of(R &&Range, UnaryPredicate P) {
1181 return std::all_of(adl_begin(Range), adl_end(Range), P);
1182}
1183
1184/// Provide wrappers to std::any_of which take ranges instead of having to pass
1185/// begin/end explicitly.
1186template <typename R, typename UnaryPredicate>
1187bool any_of(R &&Range, UnaryPredicate P) {
1188 return std::any_of(adl_begin(Range), adl_end(Range), P);
1189}
1190
1191/// Provide wrappers to std::none_of which take ranges instead of having to pass
1192/// begin/end explicitly.
1193template <typename R, typename UnaryPredicate>
1194bool none_of(R &&Range, UnaryPredicate P) {
1195 return std::none_of(adl_begin(Range), adl_end(Range), P);
1196}
1197
1198/// Provide wrappers to std::find which take ranges instead of having to pass
1199/// begin/end explicitly.
1200template <typename R, typename T>
1201auto find(R &&Range, const T &Val) -> decltype(adl_begin(Range)) {
1202 return std::find(adl_begin(Range), adl_end(Range), Val);
1203}
1204
1205/// Provide wrappers to std::find_if which take ranges instead of having to pass
1206/// begin/end explicitly.
1207template <typename R, typename UnaryPredicate>
1208auto find_if(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1209 return std::find_if(adl_begin(Range), adl_end(Range), P);
1210}
1211
1212template <typename R, typename UnaryPredicate>
1213auto find_if_not(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1214 return std::find_if_not(adl_begin(Range), adl_end(Range), P);
1215}
1216
1217/// Provide wrappers to std::remove_if which take ranges instead of having to
1218/// pass begin/end explicitly.
1219template <typename R, typename UnaryPredicate>
1220auto remove_if(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1221 return std::remove_if(adl_begin(Range), adl_end(Range), P);
1222}
1223
1224/// Provide wrappers to std::copy_if which take ranges instead of having to
1225/// pass begin/end explicitly.
1226template <typename R, typename OutputIt, typename UnaryPredicate>
1227OutputIt copy_if(R &&Range, OutputIt Out, UnaryPredicate P) {
1228 return std::copy_if(adl_begin(Range), adl_end(Range), Out, P);
1229}
1230
1231template <typename R, typename OutputIt>
1232OutputIt copy(R &&Range, OutputIt Out) {
1233 return std::copy(adl_begin(Range), adl_end(Range), Out);
1234}
1235
1236/// Wrapper function around std::find to detect if an element exists
1237/// in a container.
1238template <typename R, typename E>
1239bool is_contained(R &&Range, const E &Element) {
1240 return std::find(adl_begin(Range), adl_end(Range), Element) != adl_end(Range);
1241}
1242
1243/// Wrapper function around std::count to count the number of times an element
1244/// \p Element occurs in the given range \p Range.
1245template <typename R, typename E>
1246auto count(R &&Range, const E &Element) ->
1247 typename std::iterator_traits<decltype(adl_begin(Range))>::difference_type {
1248 return std::count(adl_begin(Range), adl_end(Range), Element);
1249}
1250
1251/// Wrapper function around std::count_if to count the number of times an
1252/// element satisfying a given predicate occurs in a range.
1253template <typename R, typename UnaryPredicate>
1254auto count_if(R &&Range, UnaryPredicate P) ->
1255 typename std::iterator_traits<decltype(adl_begin(Range))>::difference_type {
1256 return std::count_if(adl_begin(Range), adl_end(Range), P);
1257}
1258
1259/// Wrapper function around std::transform to apply a function to a range and
1260/// store the result elsewhere.
1261template <typename R, typename OutputIt, typename UnaryPredicate>
1262OutputIt transform(R &&Range, OutputIt d_first, UnaryPredicate P) {
1263 return std::transform(adl_begin(Range), adl_end(Range), d_first, P);
1264}
1265
1266/// Provide wrappers to std::partition which take ranges instead of having to
1267/// pass begin/end explicitly.
1268template <typename R, typename UnaryPredicate>
1269auto partition(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1270 return std::partition(adl_begin(Range), adl_end(Range), P);
1271}
1272
1273/// Provide wrappers to std::lower_bound which take ranges instead of having to
1274/// pass begin/end explicitly.
1275template <typename R, typename ForwardIt>
1276auto lower_bound(R &&Range, ForwardIt I) -> decltype(adl_begin(Range)) {
1277 return std::lower_bound(adl_begin(Range), adl_end(Range), I);
1278}
1279
1280template <typename R, typename ForwardIt, typename Compare>
1281auto lower_bound(R &&Range, ForwardIt I, Compare C)
1282 -> decltype(adl_begin(Range)) {
1283 return std::lower_bound(adl_begin(Range), adl_end(Range), I, C);
1284}
1285
1286/// Provide wrappers to std::upper_bound which take ranges instead of having to
1287/// pass begin/end explicitly.
1288template <typename R, typename ForwardIt>
1289auto upper_bound(R &&Range, ForwardIt I) -> decltype(adl_begin(Range)) {
1290 return std::upper_bound(adl_begin(Range), adl_end(Range), I);
1291}
1292
1293template <typename R, typename ForwardIt, typename Compare>
1294auto upper_bound(R &&Range, ForwardIt I, Compare C)
1295 -> decltype(adl_begin(Range)) {
1296 return std::upper_bound(adl_begin(Range), adl_end(Range), I, C);
1297}
1298/// Wrapper function around std::equal to detect if all elements
1299/// in a container are same.
1300template <typename R>
1301bool is_splat(R &&Range) {
1302 size_t range_size = size(Range);
1303 return range_size != 0 && (range_size == 1 ||
1304 std::equal(adl_begin(Range) + 1, adl_end(Range), adl_begin(Range)));
1305}
1306
1307/// Given a range of type R, iterate the entire range and return a
1308/// SmallVector with elements of the vector. This is useful, for example,
1309/// when you want to iterate a range and then sort the results.
1310template <unsigned Size, typename R>
1311SmallVector<typename std::remove_const<detail::ValueOfRange<R>>::type, Size>
1312to_vector(R &&Range) {
1313 return {adl_begin(Range), adl_end(Range)};
1314}
1315
1316/// Provide a container algorithm similar to C++ Library Fundamentals v2's
1317/// `erase_if` which is equivalent to:
1318///
1319/// C.erase(remove_if(C, pred), C.end());
1320///
1321/// This version works for any container with an erase method call accepting
1322/// two iterators.
1323template <typename Container, typename UnaryPredicate>
1324void erase_if(Container &C, UnaryPredicate P) {
1325 C.erase(remove_if(C, P), C.end());
1326}
1327
1328//===----------------------------------------------------------------------===//
1329// Extra additions to <memory>
1330//===----------------------------------------------------------------------===//
1331
1332// Implement make_unique according to N3656.
1333
1334/// Constructs a `new T()` with the given args and returns a
1335/// `unique_ptr<T>` which owns the object.
1336///
1337/// Example:
1338///
1339/// auto p = make_unique<int>();
1340/// auto p = make_unique<std::tuple<int, int>>(0, 1);
1341template <class T, class... Args>
1342typename std::enable_if<!std::is_array<T>::value, std::unique_ptr<T>>::type
1343make_unique(Args &&... args) {
1344 return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
21
Memory is allocated
1345}
1346
1347/// Constructs a `new T[n]` with the given args and returns a
1348/// `unique_ptr<T[]>` which owns the object.
1349///
1350/// \param n size of the new array.
1351///
1352/// Example:
1353///
1354/// auto p = make_unique<int[]>(2); // value-initializes the array with 0's.
1355template <class T>
1356typename std::enable_if<std::is_array<T>::value && std::extent<T>::value == 0,
1357 std::unique_ptr<T>>::type
1358make_unique(size_t n) {
1359 return std::unique_ptr<T>(new typename std::remove_extent<T>::type[n]());
1360}
1361
1362/// This function isn't used and is only here to provide better compile errors.
1363template <class T, class... Args>
1364typename std::enable_if<std::extent<T>::value != 0>::type
1365make_unique(Args &&...) = delete;
1366
1367struct FreeDeleter {
1368 void operator()(void* v) {
1369 ::free(v);
1370 }
1371};
1372
1373template<typename First, typename Second>
1374struct pair_hash {
1375 size_t operator()(const std::pair<First, Second> &P) const {
1376 return std::hash<First>()(P.first) * 31 + std::hash<Second>()(P.second);
1377 }
1378};
1379
1380/// A functor like C++14's std::less<void> in its absence.
1381struct less {
1382 template <typename A, typename B> bool operator()(A &&a, B &&b) const {
1383 return std::forward<A>(a) < std::forward<B>(b);
1384 }
1385};
1386
1387/// A functor like C++14's std::equal<void> in its absence.
1388struct equal {
1389 template <typename A, typename B> bool operator()(A &&a, B &&b) const {
1390 return std::forward<A>(a) == std::forward<B>(b);
1391 }
1392};
1393
1394/// Binary functor that adapts to any other binary functor after dereferencing
1395/// operands.
1396template <typename T> struct deref {
1397 T func;
1398
1399 // Could be further improved to cope with non-derivable functors and
1400 // non-binary functors (should be a variadic template member function
1401 // operator()).
1402 template <typename A, typename B>
1403 auto operator()(A &lhs, B &rhs) const -> decltype(func(*lhs, *rhs)) {
1404 assert(lhs)((lhs) ? static_cast<void> (0) : __assert_fail ("lhs", "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/ADT/STLExtras.h"
, 1404, __PRETTY_FUNCTION__))
;
1405 assert(rhs)((rhs) ? static_cast<void> (0) : __assert_fail ("rhs", "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/ADT/STLExtras.h"
, 1405, __PRETTY_FUNCTION__))
;
1406 return func(*lhs, *rhs);
1407 }
1408};
1409
1410namespace detail {
1411
1412template <typename R> class enumerator_iter;
1413
1414template <typename R> struct result_pair {
1415 friend class enumerator_iter<R>;
1416
1417 result_pair() = default;
1418 result_pair(std::size_t Index, IterOfRange<R> Iter)
1419 : Index(Index), Iter(Iter) {}
1420
1421 result_pair<R> &operator=(const result_pair<R> &Other) {
1422 Index = Other.Index;
1423 Iter = Other.Iter;
1424 return *this;
1425 }
1426
1427 std::size_t index() const { return Index; }
1428 const ValueOfRange<R> &value() const { return *Iter; }
1429 ValueOfRange<R> &value() { return *Iter; }
1430
1431private:
1432 std::size_t Index = std::numeric_limits<std::size_t>::max();
1433 IterOfRange<R> Iter;
1434};
1435
1436template <typename R>
1437class enumerator_iter
1438 : public iterator_facade_base<
1439 enumerator_iter<R>, std::forward_iterator_tag, result_pair<R>,
1440 typename std::iterator_traits<IterOfRange<R>>::difference_type,
1441 typename std::iterator_traits<IterOfRange<R>>::pointer,
1442 typename std::iterator_traits<IterOfRange<R>>::reference> {
1443 using result_type = result_pair<R>;
1444
1445public:
1446 explicit enumerator_iter(IterOfRange<R> EndIter)
1447 : Result(std::numeric_limits<size_t>::max(), EndIter) {}
1448
1449 enumerator_iter(std::size_t Index, IterOfRange<R> Iter)
1450 : Result(Index, Iter) {}
1451
1452 result_type &operator*() { return Result; }
1453 const result_type &operator*() const { return Result; }
1454
1455 enumerator_iter<R> &operator++() {
1456 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~svn350071/include/llvm/ADT/STLExtras.h"
, 1456, __PRETTY_FUNCTION__))
;
1457 ++Result.Iter;
1458 ++Result.Index;
1459 return *this;
1460 }
1461
1462 bool operator==(const enumerator_iter<R> &RHS) const {
1463 // Don't compare indices here, only iterators. It's possible for an end
1464 // iterator to have different indices depending on whether it was created
1465 // by calling std::end() versus incrementing a valid iterator.
1466 return Result.Iter == RHS.Result.Iter;
1467 }
1468
1469 enumerator_iter<R> &operator=(const enumerator_iter<R> &Other) {
1470 Result = Other.Result;
1471 return *this;
1472 }
1473
1474private:
1475 result_type Result;
1476};
1477
1478template <typename R> class enumerator {
1479public:
1480 explicit enumerator(R &&Range) : TheRange(std::forward<R>(Range)) {}
1481
1482 enumerator_iter<R> begin() {
1483 return enumerator_iter<R>(0, std::begin(TheRange));
1484 }
1485
1486 enumerator_iter<R> end() {
1487 return enumerator_iter<R>(std::end(TheRange));
1488 }
1489
1490private:
1491 R TheRange;
1492};
1493
1494} // end namespace detail
1495
1496/// Given an input range, returns a new range whose values are are pair (A,B)
1497/// such that A is the 0-based index of the item in the sequence, and B is
1498/// the value from the original sequence. Example:
1499///
1500/// std::vector<char> Items = {'A', 'B', 'C', 'D'};
1501/// for (auto X : enumerate(Items)) {
1502/// printf("Item %d - %c\n", X.index(), X.value());
1503/// }
1504///
1505/// Output:
1506/// Item 0 - A
1507/// Item 1 - B
1508/// Item 2 - C
1509/// Item 3 - D
1510///
1511template <typename R> detail::enumerator<R> enumerate(R &&TheRange) {
1512 return detail::enumerator<R>(std::forward<R>(TheRange));
1513}
1514
1515namespace detail {
1516
1517template <typename F, typename Tuple, std::size_t... I>
1518auto apply_tuple_impl(F &&f, Tuple &&t, index_sequence<I...>)
1519 -> decltype(std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...)) {
1520 return std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...);
1521}
1522
1523} // end namespace detail
1524
1525/// Given an input tuple (a1, a2, ..., an), pass the arguments of the
1526/// tuple variadically to f as if by calling f(a1, a2, ..., an) and
1527/// return the result.
1528template <typename F, typename Tuple>
1529auto apply_tuple(F &&f, Tuple &&t) -> decltype(detail::apply_tuple_impl(
1530 std::forward<F>(f), std::forward<Tuple>(t),
1531 build_index_impl<
1532 std::tuple_size<typename std::decay<Tuple>::type>::value>{})) {
1533 using Indices = build_index_impl<
1534 std::tuple_size<typename std::decay<Tuple>::type>::value>;
1535
1536 return detail::apply_tuple_impl(std::forward<F>(f), std::forward<Tuple>(t),
1537 Indices{});
1538}
1539
1540/// Return true if the sequence [Begin, End) has exactly N items. Runs in O(N)
1541/// time. Not meant for use with random-access iterators.
1542template <typename IterTy>
1543bool hasNItems(
1544 IterTy &&Begin, IterTy &&End, unsigned N,
1545 typename std::enable_if<
1546 !std::is_same<
1547 typename std::iterator_traits<typename std::remove_reference<
1548 decltype(Begin)>::type>::iterator_category,
1549 std::random_access_iterator_tag>::value,
1550 void>::type * = nullptr) {
1551 for (; N; --N, ++Begin)
1552 if (Begin == End)
1553 return false; // Too few.
1554 return Begin == End;
1555}
1556
1557/// Return true if the sequence [Begin, End) has N or more items. Runs in O(N)
1558/// time. Not meant for use with random-access iterators.
1559template <typename IterTy>
1560bool hasNItemsOrMore(
1561 IterTy &&Begin, IterTy &&End, unsigned N,
1562 typename std::enable_if<
1563 !std::is_same<
1564 typename std::iterator_traits<typename std::remove_reference<
1565 decltype(Begin)>::type>::iterator_category,
1566 std::random_access_iterator_tag>::value,
1567 void>::type * = nullptr) {
1568 for (; N; --N, ++Begin)
1569 if (Begin == End)
1570 return false; // Too few.
1571 return true;
1572}
1573
1574} // end namespace llvm
1575
1576#endif // LLVM_ADT_STLEXTRAS_H