Bug Summary

File:include/llvm/Support/Error.h
Warning:line 200, column 5
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name MetadataLoader.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-9/lib/clang/9.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-9~svn362543/build-llvm/lib/Bitcode/Reader -I /build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader -I /build/llvm-toolchain-snapshot-9~svn362543/build-llvm/include -I /build/llvm-toolchain-snapshot-9~svn362543/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/9.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-9/lib/clang/9.0.0/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-9~svn362543/build-llvm/lib/Bitcode/Reader -fdebug-prefix-map=/build/llvm-toolchain-snapshot-9~svn362543=. -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-2019-06-05-060531-1271-1 -x c++ /build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp -faddrsig

/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp

1//===- MetadataLoader.cpp - Internal BitcodeReader implementation ---------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "MetadataLoader.h"
10#include "ValueList.h"
11
12#include "llvm/ADT/APFloat.h"
13#include "llvm/ADT/APInt.h"
14#include "llvm/ADT/ArrayRef.h"
15#include "llvm/ADT/DenseMap.h"
16#include "llvm/ADT/DenseSet.h"
17#include "llvm/ADT/None.h"
18#include "llvm/ADT/STLExtras.h"
19#include "llvm/ADT/SmallString.h"
20#include "llvm/ADT/SmallVector.h"
21#include "llvm/ADT/Statistic.h"
22#include "llvm/ADT/StringRef.h"
23#include "llvm/ADT/Twine.h"
24#include "llvm/Bitcode/BitcodeReader.h"
25#include "llvm/Bitcode/BitstreamReader.h"
26#include "llvm/Bitcode/LLVMBitCodes.h"
27#include "llvm/IR/Argument.h"
28#include "llvm/IR/Attributes.h"
29#include "llvm/IR/AutoUpgrade.h"
30#include "llvm/IR/BasicBlock.h"
31#include "llvm/IR/CallingConv.h"
32#include "llvm/IR/Comdat.h"
33#include "llvm/IR/Constant.h"
34#include "llvm/IR/Constants.h"
35#include "llvm/IR/DebugInfo.h"
36#include "llvm/IR/DebugInfoMetadata.h"
37#include "llvm/IR/DebugLoc.h"
38#include "llvm/IR/DerivedTypes.h"
39#include "llvm/IR/DiagnosticPrinter.h"
40#include "llvm/IR/Function.h"
41#include "llvm/IR/GVMaterializer.h"
42#include "llvm/IR/GlobalAlias.h"
43#include "llvm/IR/GlobalIFunc.h"
44#include "llvm/IR/GlobalIndirectSymbol.h"
45#include "llvm/IR/GlobalObject.h"
46#include "llvm/IR/GlobalValue.h"
47#include "llvm/IR/GlobalVariable.h"
48#include "llvm/IR/InlineAsm.h"
49#include "llvm/IR/InstrTypes.h"
50#include "llvm/IR/Instruction.h"
51#include "llvm/IR/Instructions.h"
52#include "llvm/IR/IntrinsicInst.h"
53#include "llvm/IR/Intrinsics.h"
54#include "llvm/IR/LLVMContext.h"
55#include "llvm/IR/Module.h"
56#include "llvm/IR/ModuleSummaryIndex.h"
57#include "llvm/IR/OperandTraits.h"
58#include "llvm/IR/TrackingMDRef.h"
59#include "llvm/IR/Type.h"
60#include "llvm/IR/ValueHandle.h"
61#include "llvm/Support/AtomicOrdering.h"
62#include "llvm/Support/Casting.h"
63#include "llvm/Support/CommandLine.h"
64#include "llvm/Support/Compiler.h"
65#include "llvm/Support/Debug.h"
66#include "llvm/Support/Error.h"
67#include "llvm/Support/ErrorHandling.h"
68#include "llvm/Support/ManagedStatic.h"
69#include "llvm/Support/MemoryBuffer.h"
70#include "llvm/Support/raw_ostream.h"
71#include <algorithm>
72#include <cassert>
73#include <cstddef>
74#include <cstdint>
75#include <deque>
76#include <limits>
77#include <map>
78#include <memory>
79#include <string>
80#include <system_error>
81#include <tuple>
82#include <utility>
83#include <vector>
84
85using namespace llvm;
86
87#define DEBUG_TYPE"bitcode-reader" "bitcode-reader"
88
89STATISTIC(NumMDStringLoaded, "Number of MDStrings loaded")static llvm::Statistic NumMDStringLoaded = {"bitcode-reader",
"NumMDStringLoaded", "Number of MDStrings loaded", {0}, {false
}}
;
90STATISTIC(NumMDNodeTemporary, "Number of MDNode::Temporary created")static llvm::Statistic NumMDNodeTemporary = {"bitcode-reader"
, "NumMDNodeTemporary", "Number of MDNode::Temporary created"
, {0}, {false}}
;
91STATISTIC(NumMDRecordLoaded, "Number of Metadata records loaded")static llvm::Statistic NumMDRecordLoaded = {"bitcode-reader",
"NumMDRecordLoaded", "Number of Metadata records loaded", {0
}, {false}}
;
92
93/// Flag whether we need to import full type definitions for ThinLTO.
94/// Currently needed for Darwin and LLDB.
95static cl::opt<bool> ImportFullTypeDefinitions(
96 "import-full-type-definitions", cl::init(false), cl::Hidden,
97 cl::desc("Import full type definitions for ThinLTO."));
98
99static cl::opt<bool> DisableLazyLoading(
100 "disable-ondemand-mds-loading", cl::init(false), cl::Hidden,
101 cl::desc("Force disable the lazy-loading on-demand of metadata when "
102 "loading bitcode for importing."));
103
104namespace {
105
106static int64_t unrotateSign(uint64_t U) { return (U & 1) ? ~(U >> 1) : U >> 1; }
107
108class BitcodeReaderMetadataList {
109 /// Array of metadata references.
110 ///
111 /// Don't use std::vector here. Some versions of libc++ copy (instead of
112 /// move) on resize, and TrackingMDRef is very expensive to copy.
113 SmallVector<TrackingMDRef, 1> MetadataPtrs;
114
115 /// The set of indices in MetadataPtrs above of forward references that were
116 /// generated.
117 SmallDenseSet<unsigned, 1> ForwardReference;
118
119 /// The set of indices in MetadataPtrs above of Metadata that need to be
120 /// resolved.
121 SmallDenseSet<unsigned, 1> UnresolvedNodes;
122
123 /// Structures for resolving old type refs.
124 struct {
125 SmallDenseMap<MDString *, TempMDTuple, 1> Unknown;
126 SmallDenseMap<MDString *, DICompositeType *, 1> Final;
127 SmallDenseMap<MDString *, DICompositeType *, 1> FwdDecls;
128 SmallVector<std::pair<TrackingMDRef, TempMDTuple>, 1> Arrays;
129 } OldTypeRefs;
130
131 LLVMContext &Context;
132
133public:
134 BitcodeReaderMetadataList(LLVMContext &C) : Context(C) {}
135
136 // vector compatibility methods
137 unsigned size() const { return MetadataPtrs.size(); }
138 void resize(unsigned N) { MetadataPtrs.resize(N); }
139 void push_back(Metadata *MD) { MetadataPtrs.emplace_back(MD); }
140 void clear() { MetadataPtrs.clear(); }
141 Metadata *back() const { return MetadataPtrs.back(); }
142 void pop_back() { MetadataPtrs.pop_back(); }
143 bool empty() const { return MetadataPtrs.empty(); }
144
145 Metadata *operator[](unsigned i) const {
146 assert(i < MetadataPtrs.size())((i < MetadataPtrs.size()) ? static_cast<void> (0) :
__assert_fail ("i < MetadataPtrs.size()", "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 146, __PRETTY_FUNCTION__))
;
147 return MetadataPtrs[i];
148 }
149
150 Metadata *lookup(unsigned I) const {
151 if (I < MetadataPtrs.size())
152 return MetadataPtrs[I];
153 return nullptr;
154 }
155
156 void shrinkTo(unsigned N) {
157 assert(N <= size() && "Invalid shrinkTo request!")((N <= size() && "Invalid shrinkTo request!") ? static_cast
<void> (0) : __assert_fail ("N <= size() && \"Invalid shrinkTo request!\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 157, __PRETTY_FUNCTION__))
;
158 assert(ForwardReference.empty() && "Unexpected forward refs")((ForwardReference.empty() && "Unexpected forward refs"
) ? static_cast<void> (0) : __assert_fail ("ForwardReference.empty() && \"Unexpected forward refs\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 158, __PRETTY_FUNCTION__))
;
159 assert(UnresolvedNodes.empty() && "Unexpected unresolved node")((UnresolvedNodes.empty() && "Unexpected unresolved node"
) ? static_cast<void> (0) : __assert_fail ("UnresolvedNodes.empty() && \"Unexpected unresolved node\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 159, __PRETTY_FUNCTION__))
;
160 MetadataPtrs.resize(N);
161 }
162
163 /// Return the given metadata, creating a replaceable forward reference if
164 /// necessary.
165 Metadata *getMetadataFwdRef(unsigned Idx);
166
167 /// Return the given metadata only if it is fully resolved.
168 ///
169 /// Gives the same result as \a lookup(), unless \a MDNode::isResolved()
170 /// would give \c false.
171 Metadata *getMetadataIfResolved(unsigned Idx);
172
173 MDNode *getMDNodeFwdRefOrNull(unsigned Idx);
174 void assignValue(Metadata *MD, unsigned Idx);
175 void tryToResolveCycles();
176 bool hasFwdRefs() const { return !ForwardReference.empty(); }
177 int getNextFwdRef() {
178 assert(hasFwdRefs())((hasFwdRefs()) ? static_cast<void> (0) : __assert_fail
("hasFwdRefs()", "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 178, __PRETTY_FUNCTION__))
;
179 return *ForwardReference.begin();
180 }
181
182 /// Upgrade a type that had an MDString reference.
183 void addTypeRef(MDString &UUID, DICompositeType &CT);
184
185 /// Upgrade a type that had an MDString reference.
186 Metadata *upgradeTypeRef(Metadata *MaybeUUID);
187
188 /// Upgrade a type ref array that may have MDString references.
189 Metadata *upgradeTypeRefArray(Metadata *MaybeTuple);
190
191private:
192 Metadata *resolveTypeRefArray(Metadata *MaybeTuple);
193};
194
195void BitcodeReaderMetadataList::assignValue(Metadata *MD, unsigned Idx) {
196 if (auto *MDN = dyn_cast<MDNode>(MD))
197 if (!MDN->isResolved())
198 UnresolvedNodes.insert(Idx);
199
200 if (Idx == size()) {
201 push_back(MD);
202 return;
203 }
204
205 if (Idx >= size())
206 resize(Idx + 1);
207
208 TrackingMDRef &OldMD = MetadataPtrs[Idx];
209 if (!OldMD) {
210 OldMD.reset(MD);
211 return;
212 }
213
214 // If there was a forward reference to this value, replace it.
215 TempMDTuple PrevMD(cast<MDTuple>(OldMD.get()));
216 PrevMD->replaceAllUsesWith(MD);
217 ForwardReference.erase(Idx);
218}
219
220Metadata *BitcodeReaderMetadataList::getMetadataFwdRef(unsigned Idx) {
221 if (Idx >= size())
222 resize(Idx + 1);
223
224 if (Metadata *MD = MetadataPtrs[Idx])
225 return MD;
226
227 // Track forward refs to be resolved later.
228 ForwardReference.insert(Idx);
229
230 // Create and return a placeholder, which will later be RAUW'd.
231 ++NumMDNodeTemporary;
232 Metadata *MD = MDNode::getTemporary(Context, None).release();
233 MetadataPtrs[Idx].reset(MD);
234 return MD;
235}
236
237Metadata *BitcodeReaderMetadataList::getMetadataIfResolved(unsigned Idx) {
238 Metadata *MD = lookup(Idx);
239 if (auto *N = dyn_cast_or_null<MDNode>(MD))
240 if (!N->isResolved())
241 return nullptr;
242 return MD;
243}
244
245MDNode *BitcodeReaderMetadataList::getMDNodeFwdRefOrNull(unsigned Idx) {
246 return dyn_cast_or_null<MDNode>(getMetadataFwdRef(Idx));
247}
248
249void BitcodeReaderMetadataList::tryToResolveCycles() {
250 if (!ForwardReference.empty())
251 // Still forward references... can't resolve cycles.
252 return;
253
254 // Give up on finding a full definition for any forward decls that remain.
255 for (const auto &Ref : OldTypeRefs.FwdDecls)
256 OldTypeRefs.Final.insert(Ref);
257 OldTypeRefs.FwdDecls.clear();
258
259 // Upgrade from old type ref arrays. In strange cases, this could add to
260 // OldTypeRefs.Unknown.
261 for (const auto &Array : OldTypeRefs.Arrays)
262 Array.second->replaceAllUsesWith(resolveTypeRefArray(Array.first.get()));
263 OldTypeRefs.Arrays.clear();
264
265 // Replace old string-based type refs with the resolved node, if possible.
266 // If we haven't seen the node, leave it to the verifier to complain about
267 // the invalid string reference.
268 for (const auto &Ref : OldTypeRefs.Unknown) {
269 if (DICompositeType *CT = OldTypeRefs.Final.lookup(Ref.first))
270 Ref.second->replaceAllUsesWith(CT);
271 else
272 Ref.second->replaceAllUsesWith(Ref.first);
273 }
274 OldTypeRefs.Unknown.clear();
275
276 if (UnresolvedNodes.empty())
277 // Nothing to do.
278 return;
279
280 // Resolve any cycles.
281 for (unsigned I : UnresolvedNodes) {
282 auto &MD = MetadataPtrs[I];
283 auto *N = dyn_cast_or_null<MDNode>(MD);
284 if (!N)
285 continue;
286
287 assert(!N->isTemporary() && "Unexpected forward reference")((!N->isTemporary() && "Unexpected forward reference"
) ? static_cast<void> (0) : __assert_fail ("!N->isTemporary() && \"Unexpected forward reference\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 287, __PRETTY_FUNCTION__))
;
288 N->resolveCycles();
289 }
290
291 // Make sure we return early again until there's another unresolved ref.
292 UnresolvedNodes.clear();
293}
294
295void BitcodeReaderMetadataList::addTypeRef(MDString &UUID,
296 DICompositeType &CT) {
297 assert(CT.getRawIdentifier() == &UUID && "Mismatched UUID")((CT.getRawIdentifier() == &UUID && "Mismatched UUID"
) ? static_cast<void> (0) : __assert_fail ("CT.getRawIdentifier() == &UUID && \"Mismatched UUID\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 297, __PRETTY_FUNCTION__))
;
298 if (CT.isForwardDecl())
299 OldTypeRefs.FwdDecls.insert(std::make_pair(&UUID, &CT));
300 else
301 OldTypeRefs.Final.insert(std::make_pair(&UUID, &CT));
302}
303
304Metadata *BitcodeReaderMetadataList::upgradeTypeRef(Metadata *MaybeUUID) {
305 auto *UUID = dyn_cast_or_null<MDString>(MaybeUUID);
306 if (LLVM_LIKELY(!UUID)__builtin_expect((bool)(!UUID), true))
307 return MaybeUUID;
308
309 if (auto *CT = OldTypeRefs.Final.lookup(UUID))
310 return CT;
311
312 auto &Ref = OldTypeRefs.Unknown[UUID];
313 if (!Ref)
314 Ref = MDNode::getTemporary(Context, None);
315 return Ref.get();
316}
317
318Metadata *BitcodeReaderMetadataList::upgradeTypeRefArray(Metadata *MaybeTuple) {
319 auto *Tuple = dyn_cast_or_null<MDTuple>(MaybeTuple);
320 if (!Tuple || Tuple->isDistinct())
321 return MaybeTuple;
322
323 // Look through the array immediately if possible.
324 if (!Tuple->isTemporary())
325 return resolveTypeRefArray(Tuple);
326
327 // Create and return a placeholder to use for now. Eventually
328 // resolveTypeRefArrays() will be resolve this forward reference.
329 OldTypeRefs.Arrays.emplace_back(
330 std::piecewise_construct, std::forward_as_tuple(Tuple),
331 std::forward_as_tuple(MDTuple::getTemporary(Context, None)));
332 return OldTypeRefs.Arrays.back().second.get();
333}
334
335Metadata *BitcodeReaderMetadataList::resolveTypeRefArray(Metadata *MaybeTuple) {
336 auto *Tuple = dyn_cast_or_null<MDTuple>(MaybeTuple);
337 if (!Tuple || Tuple->isDistinct())
338 return MaybeTuple;
339
340 // Look through the DITypeRefArray, upgrading each DIType *.
341 SmallVector<Metadata *, 32> Ops;
342 Ops.reserve(Tuple->getNumOperands());
343 for (Metadata *MD : Tuple->operands())
344 Ops.push_back(upgradeTypeRef(MD));
345
346 return MDTuple::get(Context, Ops);
347}
348
349namespace {
350
351class PlaceholderQueue {
352 // Placeholders would thrash around when moved, so store in a std::deque
353 // instead of some sort of vector.
354 std::deque<DistinctMDOperandPlaceholder> PHs;
355
356public:
357 ~PlaceholderQueue() {
358 assert(empty() && "PlaceholderQueue hasn't been flushed before being destroyed")((empty() && "PlaceholderQueue hasn't been flushed before being destroyed"
) ? static_cast<void> (0) : __assert_fail ("empty() && \"PlaceholderQueue hasn't been flushed before being destroyed\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 358, __PRETTY_FUNCTION__))
;
359 }
360 bool empty() { return PHs.empty(); }
361 DistinctMDOperandPlaceholder &getPlaceholderOp(unsigned ID);
362 void flush(BitcodeReaderMetadataList &MetadataList);
363
364 /// Return the list of temporaries nodes in the queue, these need to be
365 /// loaded before we can flush the queue.
366 void getTemporaries(BitcodeReaderMetadataList &MetadataList,
367 DenseSet<unsigned> &Temporaries) {
368 for (auto &PH : PHs) {
369 auto ID = PH.getID();
370 auto *MD = MetadataList.lookup(ID);
371 if (!MD) {
372 Temporaries.insert(ID);
373 continue;
374 }
375 auto *N = dyn_cast_or_null<MDNode>(MD);
376 if (N && N->isTemporary())
377 Temporaries.insert(ID);
378 }
379 }
380};
381
382} // end anonymous namespace
383
384DistinctMDOperandPlaceholder &PlaceholderQueue::getPlaceholderOp(unsigned ID) {
385 PHs.emplace_back(ID);
386 return PHs.back();
387}
388
389void PlaceholderQueue::flush(BitcodeReaderMetadataList &MetadataList) {
390 while (!PHs.empty()) {
391 auto *MD = MetadataList.lookup(PHs.front().getID());
392 assert(MD && "Flushing placeholder on unassigned MD")((MD && "Flushing placeholder on unassigned MD") ? static_cast
<void> (0) : __assert_fail ("MD && \"Flushing placeholder on unassigned MD\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 392, __PRETTY_FUNCTION__))
;
393#ifndef NDEBUG
394 if (auto *MDN = dyn_cast<MDNode>(MD))
395 assert(MDN->isResolved() &&((MDN->isResolved() && "Flushing Placeholder while cycles aren't resolved"
) ? static_cast<void> (0) : __assert_fail ("MDN->isResolved() && \"Flushing Placeholder while cycles aren't resolved\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 396, __PRETTY_FUNCTION__))
396 "Flushing Placeholder while cycles aren't resolved")((MDN->isResolved() && "Flushing Placeholder while cycles aren't resolved"
) ? static_cast<void> (0) : __assert_fail ("MDN->isResolved() && \"Flushing Placeholder while cycles aren't resolved\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 396, __PRETTY_FUNCTION__))
;
397#endif
398 PHs.front().replaceUseWith(MD);
399 PHs.pop_front();
400 }
401}
402
403} // anonynous namespace
404
405static Error error(const Twine &Message) {
406 return make_error<StringError>(
5
Calling 'make_error<llvm::StringError, const llvm::Twine &, std::error_code>'
407 Message, make_error_code(BitcodeError::CorruptedBitcode));
408}
409
410class MetadataLoader::MetadataLoaderImpl {
411 BitcodeReaderMetadataList MetadataList;
412 BitcodeReaderValueList &ValueList;
413 BitstreamCursor &Stream;
414 LLVMContext &Context;
415 Module &TheModule;
416 std::function<Type *(unsigned)> getTypeByID;
417
418 /// Cursor associated with the lazy-loading of Metadata. This is the easy way
419 /// to keep around the right "context" (Abbrev list) to be able to jump in
420 /// the middle of the metadata block and load any record.
421 BitstreamCursor IndexCursor;
422
423 /// Index that keeps track of MDString values.
424 std::vector<StringRef> MDStringRef;
425
426 /// On-demand loading of a single MDString. Requires the index above to be
427 /// populated.
428 MDString *lazyLoadOneMDString(unsigned Idx);
429
430 /// Index that keeps track of where to find a metadata record in the stream.
431 std::vector<uint64_t> GlobalMetadataBitPosIndex;
432
433 /// Populate the index above to enable lazily loading of metadata, and load
434 /// the named metadata as well as the transitively referenced global
435 /// Metadata.
436 Expected<bool> lazyLoadModuleMetadataBlock();
437
438 /// On-demand loading of a single metadata. Requires the index above to be
439 /// populated.
440 void lazyLoadOneMetadata(unsigned Idx, PlaceholderQueue &Placeholders);
441
442 // Keep mapping of seens pair of old-style CU <-> SP, and update pointers to
443 // point from SP to CU after a block is completly parsed.
444 std::vector<std::pair<DICompileUnit *, Metadata *>> CUSubprograms;
445
446 /// Functions that need to be matched with subprograms when upgrading old
447 /// metadata.
448 SmallDenseMap<Function *, DISubprogram *, 16> FunctionsWithSPs;
449
450 // Map the bitcode's custom MDKind ID to the Module's MDKind ID.
451 DenseMap<unsigned, unsigned> MDKindMap;
452
453 bool StripTBAA = false;
454 bool HasSeenOldLoopTags = false;
455 bool NeedUpgradeToDIGlobalVariableExpression = false;
456 bool NeedDeclareExpressionUpgrade = false;
457
458 /// True if metadata is being parsed for a module being ThinLTO imported.
459 bool IsImporting = false;
460
461 Error parseOneMetadata(SmallVectorImpl<uint64_t> &Record, unsigned Code,
462 PlaceholderQueue &Placeholders, StringRef Blob,
463 unsigned &NextMetadataNo);
464 Error parseMetadataStrings(ArrayRef<uint64_t> Record, StringRef Blob,
465 function_ref<void(StringRef)> CallBack);
466 Error parseGlobalObjectAttachment(GlobalObject &GO,
467 ArrayRef<uint64_t> Record);
468 Error parseMetadataKindRecord(SmallVectorImpl<uint64_t> &Record);
469
470 void resolveForwardRefsAndPlaceholders(PlaceholderQueue &Placeholders);
471
472 /// Upgrade old-style CU <-> SP pointers to point from SP to CU.
473 void upgradeCUSubprograms() {
474 for (auto CU_SP : CUSubprograms)
475 if (auto *SPs = dyn_cast_or_null<MDTuple>(CU_SP.second))
476 for (auto &Op : SPs->operands())
477 if (auto *SP = dyn_cast_or_null<DISubprogram>(Op))
478 SP->replaceUnit(CU_SP.first);
479 CUSubprograms.clear();
480 }
481
482 /// Upgrade old-style bare DIGlobalVariables to DIGlobalVariableExpressions.
483 void upgradeCUVariables() {
484 if (!NeedUpgradeToDIGlobalVariableExpression)
485 return;
486
487 // Upgrade list of variables attached to the CUs.
488 if (NamedMDNode *CUNodes = TheModule.getNamedMetadata("llvm.dbg.cu"))
489 for (unsigned I = 0, E = CUNodes->getNumOperands(); I != E; ++I) {
490 auto *CU = cast<DICompileUnit>(CUNodes->getOperand(I));
491 if (auto *GVs = dyn_cast_or_null<MDTuple>(CU->getRawGlobalVariables()))
492 for (unsigned I = 0; I < GVs->getNumOperands(); I++)
493 if (auto *GV =
494 dyn_cast_or_null<DIGlobalVariable>(GVs->getOperand(I))) {
495 auto *DGVE = DIGlobalVariableExpression::getDistinct(
496 Context, GV, DIExpression::get(Context, {}));
497 GVs->replaceOperandWith(I, DGVE);
498 }
499 }
500
501 // Upgrade variables attached to globals.
502 for (auto &GV : TheModule.globals()) {
503 SmallVector<MDNode *, 1> MDs;
504 GV.getMetadata(LLVMContext::MD_dbg, MDs);
505 GV.eraseMetadata(LLVMContext::MD_dbg);
506 for (auto *MD : MDs)
507 if (auto *DGV = dyn_cast_or_null<DIGlobalVariable>(MD)) {
508 auto *DGVE = DIGlobalVariableExpression::getDistinct(
509 Context, DGV, DIExpression::get(Context, {}));
510 GV.addMetadata(LLVMContext::MD_dbg, *DGVE);
511 } else
512 GV.addMetadata(LLVMContext::MD_dbg, *MD);
513 }
514 }
515
516 /// Remove a leading DW_OP_deref from DIExpressions in a dbg.declare that
517 /// describes a function argument.
518 void upgradeDeclareExpressions(Function &F) {
519 if (!NeedDeclareExpressionUpgrade)
520 return;
521
522 for (auto &BB : F)
523 for (auto &I : BB)
524 if (auto *DDI = dyn_cast<DbgDeclareInst>(&I))
525 if (auto *DIExpr = DDI->getExpression())
526 if (DIExpr->startsWithDeref() &&
527 dyn_cast_or_null<Argument>(DDI->getAddress())) {
528 SmallVector<uint64_t, 8> Ops;
529 Ops.append(std::next(DIExpr->elements_begin()),
530 DIExpr->elements_end());
531 auto *E = DIExpression::get(Context, Ops);
532 DDI->setOperand(2, MetadataAsValue::get(Context, E));
533 }
534 }
535
536 /// Upgrade the expression from previous versions.
537 Error upgradeDIExpression(uint64_t FromVersion,
538 MutableArrayRef<uint64_t> &Expr,
539 SmallVectorImpl<uint64_t> &Buffer) {
540 auto N = Expr.size();
541 switch (FromVersion) {
542 default:
543 return error("Invalid record");
544 case 0:
545 if (N >= 3 && Expr[N - 3] == dwarf::DW_OP_bit_piece)
546 Expr[N - 3] = dwarf::DW_OP_LLVM_fragment;
547 LLVM_FALLTHROUGH[[clang::fallthrough]];
548 case 1:
549 // Move DW_OP_deref to the end.
550 if (N && Expr[0] == dwarf::DW_OP_deref) {
551 auto End = Expr.end();
552 if (Expr.size() >= 3 &&
553 *std::prev(End, 3) == dwarf::DW_OP_LLVM_fragment)
554 End = std::prev(End, 3);
555 std::move(std::next(Expr.begin()), End, Expr.begin());
556 *std::prev(End) = dwarf::DW_OP_deref;
557 }
558 NeedDeclareExpressionUpgrade = true;
559 LLVM_FALLTHROUGH[[clang::fallthrough]];
560 case 2: {
561 // Change DW_OP_plus to DW_OP_plus_uconst.
562 // Change DW_OP_minus to DW_OP_uconst, DW_OP_minus
563 auto SubExpr = ArrayRef<uint64_t>(Expr);
564 while (!SubExpr.empty()) {
565 // Skip past other operators with their operands
566 // for this version of the IR, obtained from
567 // from historic DIExpression::ExprOperand::getSize().
568 size_t HistoricSize;
569 switch (SubExpr.front()) {
570 default:
571 HistoricSize = 1;
572 break;
573 case dwarf::DW_OP_constu:
574 case dwarf::DW_OP_minus:
575 case dwarf::DW_OP_plus:
576 HistoricSize = 2;
577 break;
578 case dwarf::DW_OP_LLVM_fragment:
579 HistoricSize = 3;
580 break;
581 }
582
583 // If the expression is malformed, make sure we don't
584 // copy more elements than we should.
585 HistoricSize = std::min(SubExpr.size(), HistoricSize);
586 ArrayRef<uint64_t> Args = SubExpr.slice(1, HistoricSize-1);
587
588 switch (SubExpr.front()) {
589 case dwarf::DW_OP_plus:
590 Buffer.push_back(dwarf::DW_OP_plus_uconst);
591 Buffer.append(Args.begin(), Args.end());
592 break;
593 case dwarf::DW_OP_minus:
594 Buffer.push_back(dwarf::DW_OP_constu);
595 Buffer.append(Args.begin(), Args.end());
596 Buffer.push_back(dwarf::DW_OP_minus);
597 break;
598 default:
599 Buffer.push_back(*SubExpr.begin());
600 Buffer.append(Args.begin(), Args.end());
601 break;
602 }
603
604 // Continue with remaining elements.
605 SubExpr = SubExpr.slice(HistoricSize);
606 }
607 Expr = MutableArrayRef<uint64_t>(Buffer);
608 LLVM_FALLTHROUGH[[clang::fallthrough]];
609 }
610 case 3:
611 // Up-to-date!
612 break;
613 }
614
615 return Error::success();
616 }
617
618 void upgradeDebugInfo() {
619 upgradeCUSubprograms();
620 upgradeCUVariables();
621 }
622
623public:
624 MetadataLoaderImpl(BitstreamCursor &Stream, Module &TheModule,
625 BitcodeReaderValueList &ValueList,
626 std::function<Type *(unsigned)> getTypeByID,
627 bool IsImporting)
628 : MetadataList(TheModule.getContext()), ValueList(ValueList),
629 Stream(Stream), Context(TheModule.getContext()), TheModule(TheModule),
630 getTypeByID(std::move(getTypeByID)), IsImporting(IsImporting) {}
631
632 Error parseMetadata(bool ModuleLevel);
633
634 bool hasFwdRefs() const { return MetadataList.hasFwdRefs(); }
635
636 Metadata *getMetadataFwdRefOrLoad(unsigned ID) {
637 if (ID < MDStringRef.size())
638 return lazyLoadOneMDString(ID);
639 if (auto *MD = MetadataList.lookup(ID))
640 return MD;
641 // If lazy-loading is enabled, we try recursively to load the operand
642 // instead of creating a temporary.
643 if (ID < (MDStringRef.size() + GlobalMetadataBitPosIndex.size())) {
644 PlaceholderQueue Placeholders;
645 lazyLoadOneMetadata(ID, Placeholders);
646 resolveForwardRefsAndPlaceholders(Placeholders);
647 return MetadataList.lookup(ID);
648 }
649 return MetadataList.getMetadataFwdRef(ID);
650 }
651
652 DISubprogram *lookupSubprogramForFunction(Function *F) {
653 return FunctionsWithSPs.lookup(F);
654 }
655
656 bool hasSeenOldLoopTags() { return HasSeenOldLoopTags; }
657
658 Error parseMetadataAttachment(
659 Function &F, const SmallVectorImpl<Instruction *> &InstructionList);
660
661 Error parseMetadataKinds();
662
663 void setStripTBAA(bool Value) { StripTBAA = Value; }
664 bool isStrippingTBAA() { return StripTBAA; }
665
666 unsigned size() const { return MetadataList.size(); }
667 void shrinkTo(unsigned N) { MetadataList.shrinkTo(N); }
668 void upgradeDebugIntrinsics(Function &F) { upgradeDeclareExpressions(F); }
669};
670
671Expected<bool>
672MetadataLoader::MetadataLoaderImpl::lazyLoadModuleMetadataBlock() {
673 IndexCursor = Stream;
674 SmallVector<uint64_t, 64> Record;
675 // Get the abbrevs, and preload record positions to make them lazy-loadable.
676 while (true) {
677 BitstreamEntry Entry = IndexCursor.advanceSkippingSubblocks(
678 BitstreamCursor::AF_DontPopBlockAtEnd);
679 switch (Entry.Kind) {
680 case BitstreamEntry::SubBlock: // Handled for us already.
681 case BitstreamEntry::Error:
682 return error("Malformed block");
683 case BitstreamEntry::EndBlock: {
684 return true;
685 }
686 case BitstreamEntry::Record: {
687 // The interesting case.
688 ++NumMDRecordLoaded;
689 uint64_t CurrentPos = IndexCursor.GetCurrentBitNo();
690 auto Code = IndexCursor.skipRecord(Entry.ID);
691 switch (Code) {
692 case bitc::METADATA_STRINGS: {
693 // Rewind and parse the strings.
694 IndexCursor.JumpToBit(CurrentPos);
695 StringRef Blob;
696 Record.clear();
697 IndexCursor.readRecord(Entry.ID, Record, &Blob);
698 unsigned NumStrings = Record[0];
699 MDStringRef.reserve(NumStrings);
700 auto IndexNextMDString = [&](StringRef Str) {
701 MDStringRef.push_back(Str);
702 };
703 if (auto Err = parseMetadataStrings(Record, Blob, IndexNextMDString))
704 return std::move(Err);
705 break;
706 }
707 case bitc::METADATA_INDEX_OFFSET: {
708 // This is the offset to the index, when we see this we skip all the
709 // records and load only an index to these.
710 IndexCursor.JumpToBit(CurrentPos);
711 Record.clear();
712 IndexCursor.readRecord(Entry.ID, Record);
713 if (Record.size() != 2)
714 return error("Invalid record");
715 auto Offset = Record[0] + (Record[1] << 32);
716 auto BeginPos = IndexCursor.GetCurrentBitNo();
717 IndexCursor.JumpToBit(BeginPos + Offset);
718 Entry = IndexCursor.advanceSkippingSubblocks(
719 BitstreamCursor::AF_DontPopBlockAtEnd);
720 assert(Entry.Kind == BitstreamEntry::Record &&((Entry.Kind == BitstreamEntry::Record && "Corrupted bitcode: Expected `Record` when trying to find the "
"Metadata index") ? static_cast<void> (0) : __assert_fail
("Entry.Kind == BitstreamEntry::Record && \"Corrupted bitcode: Expected `Record` when trying to find the \" \"Metadata index\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 722, __PRETTY_FUNCTION__))
721 "Corrupted bitcode: Expected `Record` when trying to find the "((Entry.Kind == BitstreamEntry::Record && "Corrupted bitcode: Expected `Record` when trying to find the "
"Metadata index") ? static_cast<void> (0) : __assert_fail
("Entry.Kind == BitstreamEntry::Record && \"Corrupted bitcode: Expected `Record` when trying to find the \" \"Metadata index\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 722, __PRETTY_FUNCTION__))
722 "Metadata index")((Entry.Kind == BitstreamEntry::Record && "Corrupted bitcode: Expected `Record` when trying to find the "
"Metadata index") ? static_cast<void> (0) : __assert_fail
("Entry.Kind == BitstreamEntry::Record && \"Corrupted bitcode: Expected `Record` when trying to find the \" \"Metadata index\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 722, __PRETTY_FUNCTION__))
;
723 Record.clear();
724 auto Code = IndexCursor.readRecord(Entry.ID, Record);
725 (void)Code;
726 assert(Code == bitc::METADATA_INDEX && "Corrupted bitcode: Expected "((Code == bitc::METADATA_INDEX && "Corrupted bitcode: Expected "
"`METADATA_INDEX` when trying " "to find the Metadata index"
) ? static_cast<void> (0) : __assert_fail ("Code == bitc::METADATA_INDEX && \"Corrupted bitcode: Expected \" \"`METADATA_INDEX` when trying \" \"to find the Metadata index\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 728, __PRETTY_FUNCTION__))
727 "`METADATA_INDEX` when trying "((Code == bitc::METADATA_INDEX && "Corrupted bitcode: Expected "
"`METADATA_INDEX` when trying " "to find the Metadata index"
) ? static_cast<void> (0) : __assert_fail ("Code == bitc::METADATA_INDEX && \"Corrupted bitcode: Expected \" \"`METADATA_INDEX` when trying \" \"to find the Metadata index\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 728, __PRETTY_FUNCTION__))
728 "to find the Metadata index")((Code == bitc::METADATA_INDEX && "Corrupted bitcode: Expected "
"`METADATA_INDEX` when trying " "to find the Metadata index"
) ? static_cast<void> (0) : __assert_fail ("Code == bitc::METADATA_INDEX && \"Corrupted bitcode: Expected \" \"`METADATA_INDEX` when trying \" \"to find the Metadata index\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 728, __PRETTY_FUNCTION__))
;
729
730 // Delta unpack
731 auto CurrentValue = BeginPos;
732 GlobalMetadataBitPosIndex.reserve(Record.size());
733 for (auto &Elt : Record) {
734 CurrentValue += Elt;
735 GlobalMetadataBitPosIndex.push_back(CurrentValue);
736 }
737 break;
738 }
739 case bitc::METADATA_INDEX:
740 // We don't expect to get there, the Index is loaded when we encounter
741 // the offset.
742 return error("Corrupted Metadata block");
743 case bitc::METADATA_NAME: {
744 // Named metadata need to be materialized now and aren't deferred.
745 IndexCursor.JumpToBit(CurrentPos);
746 Record.clear();
747 unsigned Code = IndexCursor.readRecord(Entry.ID, Record);
748 assert(Code == bitc::METADATA_NAME)((Code == bitc::METADATA_NAME) ? static_cast<void> (0) :
__assert_fail ("Code == bitc::METADATA_NAME", "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 748, __PRETTY_FUNCTION__))
;
749
750 // Read name of the named metadata.
751 SmallString<8> Name(Record.begin(), Record.end());
752 Code = IndexCursor.ReadCode();
753
754 // Named Metadata comes in two parts, we expect the name to be followed
755 // by the node
756 Record.clear();
757 unsigned NextBitCode = IndexCursor.readRecord(Code, Record);
758 assert(NextBitCode == bitc::METADATA_NAMED_NODE)((NextBitCode == bitc::METADATA_NAMED_NODE) ? static_cast<
void> (0) : __assert_fail ("NextBitCode == bitc::METADATA_NAMED_NODE"
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 758, __PRETTY_FUNCTION__))
;
759 (void)NextBitCode;
760
761 // Read named metadata elements.
762 unsigned Size = Record.size();
763 NamedMDNode *NMD = TheModule.getOrInsertNamedMetadata(Name);
764 for (unsigned i = 0; i != Size; ++i) {
765 // FIXME: We could use a placeholder here, however NamedMDNode are
766 // taking MDNode as operand and not using the Metadata infrastructure.
767 // It is acknowledged by 'TODO: Inherit from Metadata' in the
768 // NamedMDNode class definition.
769 MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[i]);
770 assert(MD && "Invalid metadata: expect fwd ref to MDNode")((MD && "Invalid metadata: expect fwd ref to MDNode")
? static_cast<void> (0) : __assert_fail ("MD && \"Invalid metadata: expect fwd ref to MDNode\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 770, __PRETTY_FUNCTION__))
;
771 NMD->addOperand(MD);
772 }
773 break;
774 }
775 case bitc::METADATA_GLOBAL_DECL_ATTACHMENT: {
776 // FIXME: we need to do this early because we don't materialize global
777 // value explicitly.
778 IndexCursor.JumpToBit(CurrentPos);
779 Record.clear();
780 IndexCursor.readRecord(Entry.ID, Record);
781 if (Record.size() % 2 == 0)
782 return error("Invalid record");
783 unsigned ValueID = Record[0];
784 if (ValueID >= ValueList.size())
785 return error("Invalid record");
786 if (auto *GO = dyn_cast<GlobalObject>(ValueList[ValueID]))
787 if (Error Err = parseGlobalObjectAttachment(
788 *GO, ArrayRef<uint64_t>(Record).slice(1)))
789 return std::move(Err);
790 break;
791 }
792 case bitc::METADATA_KIND:
793 case bitc::METADATA_STRING_OLD:
794 case bitc::METADATA_OLD_FN_NODE:
795 case bitc::METADATA_OLD_NODE:
796 case bitc::METADATA_VALUE:
797 case bitc::METADATA_DISTINCT_NODE:
798 case bitc::METADATA_NODE:
799 case bitc::METADATA_LOCATION:
800 case bitc::METADATA_GENERIC_DEBUG:
801 case bitc::METADATA_SUBRANGE:
802 case bitc::METADATA_ENUMERATOR:
803 case bitc::METADATA_BASIC_TYPE:
804 case bitc::METADATA_DERIVED_TYPE:
805 case bitc::METADATA_COMPOSITE_TYPE:
806 case bitc::METADATA_SUBROUTINE_TYPE:
807 case bitc::METADATA_MODULE:
808 case bitc::METADATA_FILE:
809 case bitc::METADATA_COMPILE_UNIT:
810 case bitc::METADATA_SUBPROGRAM:
811 case bitc::METADATA_LEXICAL_BLOCK:
812 case bitc::METADATA_LEXICAL_BLOCK_FILE:
813 case bitc::METADATA_NAMESPACE:
814 case bitc::METADATA_COMMON_BLOCK:
815 case bitc::METADATA_MACRO:
816 case bitc::METADATA_MACRO_FILE:
817 case bitc::METADATA_TEMPLATE_TYPE:
818 case bitc::METADATA_TEMPLATE_VALUE:
819 case bitc::METADATA_GLOBAL_VAR:
820 case bitc::METADATA_LOCAL_VAR:
821 case bitc::METADATA_LABEL:
822 case bitc::METADATA_EXPRESSION:
823 case bitc::METADATA_OBJC_PROPERTY:
824 case bitc::METADATA_IMPORTED_ENTITY:
825 case bitc::METADATA_GLOBAL_VAR_EXPR:
826 // We don't expect to see any of these, if we see one, give up on
827 // lazy-loading and fallback.
828 MDStringRef.clear();
829 GlobalMetadataBitPosIndex.clear();
830 return false;
831 }
832 break;
833 }
834 }
835 }
836}
837
838/// Parse a METADATA_BLOCK. If ModuleLevel is true then we are parsing
839/// module level metadata.
840Error MetadataLoader::MetadataLoaderImpl::parseMetadata(bool ModuleLevel) {
841 if (!ModuleLevel && MetadataList.hasFwdRefs())
842 return error("Invalid metadata: fwd refs into function blocks");
843
844 // Record the entry position so that we can jump back here and efficiently
845 // skip the whole block in case we lazy-load.
846 auto EntryPos = Stream.GetCurrentBitNo();
847
848 if (Stream.EnterSubBlock(bitc::METADATA_BLOCK_ID))
849 return error("Invalid record");
850
851 SmallVector<uint64_t, 64> Record;
852 PlaceholderQueue Placeholders;
853
854 // We lazy-load module-level metadata: we build an index for each record, and
855 // then load individual record as needed, starting with the named metadata.
856 if (ModuleLevel && IsImporting && MetadataList.empty() &&
857 !DisableLazyLoading) {
858 auto SuccessOrErr = lazyLoadModuleMetadataBlock();
859 if (!SuccessOrErr)
860 return SuccessOrErr.takeError();
861 if (SuccessOrErr.get()) {
862 // An index was successfully created and we will be able to load metadata
863 // on-demand.
864 MetadataList.resize(MDStringRef.size() +
865 GlobalMetadataBitPosIndex.size());
866
867 // Reading the named metadata created forward references and/or
868 // placeholders, that we flush here.
869 resolveForwardRefsAndPlaceholders(Placeholders);
870 upgradeDebugInfo();
871 // Return at the beginning of the block, since it is easy to skip it
872 // entirely from there.
873 Stream.ReadBlockEnd(); // Pop the abbrev block context.
874 Stream.JumpToBit(EntryPos);
875 if (Stream.SkipBlock())
876 return error("Invalid record");
877 return Error::success();
878 }
879 // Couldn't load an index, fallback to loading all the block "old-style".
880 }
881
882 unsigned NextMetadataNo = MetadataList.size();
883
884 // Read all the records.
885 while (true) {
886 BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
887
888 switch (Entry.Kind) {
889 case BitstreamEntry::SubBlock: // Handled for us already.
890 case BitstreamEntry::Error:
891 return error("Malformed block");
892 case BitstreamEntry::EndBlock:
893 resolveForwardRefsAndPlaceholders(Placeholders);
894 upgradeDebugInfo();
895 return Error::success();
896 case BitstreamEntry::Record:
897 // The interesting case.
898 break;
899 }
900
901 // Read a record.
902 Record.clear();
903 StringRef Blob;
904 ++NumMDRecordLoaded;
905 unsigned Code = Stream.readRecord(Entry.ID, Record, &Blob);
906 if (Error Err =
907 parseOneMetadata(Record, Code, Placeholders, Blob, NextMetadataNo))
908 return Err;
909 }
910}
911
912MDString *MetadataLoader::MetadataLoaderImpl::lazyLoadOneMDString(unsigned ID) {
913 ++NumMDStringLoaded;
914 if (Metadata *MD = MetadataList.lookup(ID))
915 return cast<MDString>(MD);
916 auto MDS = MDString::get(Context, MDStringRef[ID]);
917 MetadataList.assignValue(MDS, ID);
918 return MDS;
919}
920
921void MetadataLoader::MetadataLoaderImpl::lazyLoadOneMetadata(
922 unsigned ID, PlaceholderQueue &Placeholders) {
923 assert(ID < (MDStringRef.size()) + GlobalMetadataBitPosIndex.size())((ID < (MDStringRef.size()) + GlobalMetadataBitPosIndex.size
()) ? static_cast<void> (0) : __assert_fail ("ID < (MDStringRef.size()) + GlobalMetadataBitPosIndex.size()"
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 923, __PRETTY_FUNCTION__))
;
924 assert(ID >= MDStringRef.size() && "Unexpected lazy-loading of MDString")((ID >= MDStringRef.size() && "Unexpected lazy-loading of MDString"
) ? static_cast<void> (0) : __assert_fail ("ID >= MDStringRef.size() && \"Unexpected lazy-loading of MDString\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 924, __PRETTY_FUNCTION__))
;
925 // Lookup first if the metadata hasn't already been loaded.
926 if (auto *MD = MetadataList.lookup(ID)) {
927 auto *N = dyn_cast_or_null<MDNode>(MD);
928 if (!N->isTemporary())
929 return;
930 }
931 SmallVector<uint64_t, 64> Record;
932 StringRef Blob;
933 IndexCursor.JumpToBit(GlobalMetadataBitPosIndex[ID - MDStringRef.size()]);
934 auto Entry = IndexCursor.advanceSkippingSubblocks();
935 ++NumMDRecordLoaded;
936 unsigned Code = IndexCursor.readRecord(Entry.ID, Record, &Blob);
937 if (Error Err = parseOneMetadata(Record, Code, Placeholders, Blob, ID))
938 report_fatal_error("Can't lazyload MD");
939}
940
941/// Ensure that all forward-references and placeholders are resolved.
942/// Iteratively lazy-loading metadata on-demand if needed.
943void MetadataLoader::MetadataLoaderImpl::resolveForwardRefsAndPlaceholders(
944 PlaceholderQueue &Placeholders) {
945 DenseSet<unsigned> Temporaries;
946 while (1) {
947 // Populate Temporaries with the placeholders that haven't been loaded yet.
948 Placeholders.getTemporaries(MetadataList, Temporaries);
949
950 // If we don't have any temporary, or FwdReference, we're done!
951 if (Temporaries.empty() && !MetadataList.hasFwdRefs())
952 break;
953
954 // First, load all the temporaries. This can add new placeholders or
955 // forward references.
956 for (auto ID : Temporaries)
957 lazyLoadOneMetadata(ID, Placeholders);
958 Temporaries.clear();
959
960 // Second, load the forward-references. This can also add new placeholders
961 // or forward references.
962 while (MetadataList.hasFwdRefs())
963 lazyLoadOneMetadata(MetadataList.getNextFwdRef(), Placeholders);
964 }
965 // At this point we don't have any forward reference remaining, or temporary
966 // that haven't been loaded. We can safely drop RAUW support and mark cycles
967 // as resolved.
968 MetadataList.tryToResolveCycles();
969
970 // Finally, everything is in place, we can replace the placeholders operands
971 // with the final node they refer to.
972 Placeholders.flush(MetadataList);
973}
974
975Error MetadataLoader::MetadataLoaderImpl::parseOneMetadata(
976 SmallVectorImpl<uint64_t> &Record, unsigned Code,
977 PlaceholderQueue &Placeholders, StringRef Blob, unsigned &NextMetadataNo) {
978
979 bool IsDistinct = false;
980 auto getMD = [&](unsigned ID) -> Metadata * {
981 if (ID < MDStringRef.size())
982 return lazyLoadOneMDString(ID);
983 if (!IsDistinct) {
984 if (auto *MD = MetadataList.lookup(ID))
985 return MD;
986 // If lazy-loading is enabled, we try recursively to load the operand
987 // instead of creating a temporary.
988 if (ID < (MDStringRef.size() + GlobalMetadataBitPosIndex.size())) {
989 // Create a temporary for the node that is referencing the operand we
990 // will lazy-load. It is needed before recursing in case there are
991 // uniquing cycles.
992 MetadataList.getMetadataFwdRef(NextMetadataNo);
993 lazyLoadOneMetadata(ID, Placeholders);
994 return MetadataList.lookup(ID);
995 }
996 // Return a temporary.
997 return MetadataList.getMetadataFwdRef(ID);
998 }
999 if (auto *MD = MetadataList.getMetadataIfResolved(ID))
1000 return MD;
1001 return &Placeholders.getPlaceholderOp(ID);
1002 };
1003 auto getMDOrNull = [&](unsigned ID) -> Metadata * {
1004 if (ID)
1005 return getMD(ID - 1);
1006 return nullptr;
1007 };
1008 auto getMDOrNullWithoutPlaceholders = [&](unsigned ID) -> Metadata * {
1009 if (ID)
1010 return MetadataList.getMetadataFwdRef(ID - 1);
1011 return nullptr;
1012 };
1013 auto getMDString = [&](unsigned ID) -> MDString * {
1014 // This requires that the ID is not really a forward reference. In
1015 // particular, the MDString must already have been resolved.
1016 auto MDS = getMDOrNull(ID);
1017 return cast_or_null<MDString>(MDS);
1018 };
1019
1020 // Support for old type refs.
1021 auto getDITypeRefOrNull = [&](unsigned ID) {
1022 return MetadataList.upgradeTypeRef(getMDOrNull(ID));
1023 };
1024
1025#define GET_OR_DISTINCT(CLASS, ARGS) \
1026 (IsDistinct ? CLASS::getDistinct ARGS : CLASS::get ARGS)
1027
1028 switch (Code) {
1029 default: // Default behavior: ignore.
1030 break;
1031 case bitc::METADATA_NAME: {
1032 // Read name of the named metadata.
1033 SmallString<8> Name(Record.begin(), Record.end());
1034 Record.clear();
1035 Code = Stream.ReadCode();
1036
1037 ++NumMDRecordLoaded;
1038 unsigned NextBitCode = Stream.readRecord(Code, Record);
1039 if (NextBitCode != bitc::METADATA_NAMED_NODE)
1040 return error("METADATA_NAME not followed by METADATA_NAMED_NODE");
1041
1042 // Read named metadata elements.
1043 unsigned Size = Record.size();
1044 NamedMDNode *NMD = TheModule.getOrInsertNamedMetadata(Name);
1045 for (unsigned i = 0; i != Size; ++i) {
1046 MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[i]);
1047 if (!MD)
1048 return error("Invalid named metadata: expect fwd ref to MDNode");
1049 NMD->addOperand(MD);
1050 }
1051 break;
1052 }
1053 case bitc::METADATA_OLD_FN_NODE: {
1054 // FIXME: Remove in 4.0.
1055 // This is a LocalAsMetadata record, the only type of function-local
1056 // metadata.
1057 if (Record.size() % 2 == 1)
1058 return error("Invalid record");
1059
1060 // If this isn't a LocalAsMetadata record, we're dropping it. This used
1061 // to be legal, but there's no upgrade path.
1062 auto dropRecord = [&] {
1063 MetadataList.assignValue(MDNode::get(Context, None), NextMetadataNo);
1064 NextMetadataNo++;
1065 };
1066 if (Record.size() != 2) {
1067 dropRecord();
1068 break;
1069 }
1070
1071 Type *Ty = getTypeByID(Record[0]);
1072 if (Ty->isMetadataTy() || Ty->isVoidTy()) {
1073 dropRecord();
1074 break;
1075 }
1076
1077 MetadataList.assignValue(
1078 LocalAsMetadata::get(ValueList.getValueFwdRef(Record[1], Ty)),
1079 NextMetadataNo);
1080 NextMetadataNo++;
1081 break;
1082 }
1083 case bitc::METADATA_OLD_NODE: {
1084 // FIXME: Remove in 4.0.
1085 if (Record.size() % 2 == 1)
1086 return error("Invalid record");
1087
1088 unsigned Size = Record.size();
1089 SmallVector<Metadata *, 8> Elts;
1090 for (unsigned i = 0; i != Size; i += 2) {
1091 Type *Ty = getTypeByID(Record[i]);
1092 if (!Ty)
1093 return error("Invalid record");
1094 if (Ty->isMetadataTy())
1095 Elts.push_back(getMD(Record[i + 1]));
1096 else if (!Ty->isVoidTy()) {
1097 auto *MD =
1098 ValueAsMetadata::get(ValueList.getValueFwdRef(Record[i + 1], Ty));
1099 assert(isa<ConstantAsMetadata>(MD) &&((isa<ConstantAsMetadata>(MD) && "Expected non-function-local metadata"
) ? static_cast<void> (0) : __assert_fail ("isa<ConstantAsMetadata>(MD) && \"Expected non-function-local metadata\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 1100, __PRETTY_FUNCTION__))
1100 "Expected non-function-local metadata")((isa<ConstantAsMetadata>(MD) && "Expected non-function-local metadata"
) ? static_cast<void> (0) : __assert_fail ("isa<ConstantAsMetadata>(MD) && \"Expected non-function-local metadata\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 1100, __PRETTY_FUNCTION__))
;
1101 Elts.push_back(MD);
1102 } else
1103 Elts.push_back(nullptr);
1104 }
1105 MetadataList.assignValue(MDNode::get(Context, Elts), NextMetadataNo);
1106 NextMetadataNo++;
1107 break;
1108 }
1109 case bitc::METADATA_VALUE: {
1110 if (Record.size() != 2)
1111 return error("Invalid record");
1112
1113 Type *Ty = getTypeByID(Record[0]);
1114 if (Ty->isMetadataTy() || Ty->isVoidTy())
1115 return error("Invalid record");
1116
1117 MetadataList.assignValue(
1118 ValueAsMetadata::get(ValueList.getValueFwdRef(Record[1], Ty)),
1119 NextMetadataNo);
1120 NextMetadataNo++;
1121 break;
1122 }
1123 case bitc::METADATA_DISTINCT_NODE:
1124 IsDistinct = true;
1125 LLVM_FALLTHROUGH[[clang::fallthrough]];
1126 case bitc::METADATA_NODE: {
1127 SmallVector<Metadata *, 8> Elts;
1128 Elts.reserve(Record.size());
1129 for (unsigned ID : Record)
1130 Elts.push_back(getMDOrNull(ID));
1131 MetadataList.assignValue(IsDistinct ? MDNode::getDistinct(Context, Elts)
1132 : MDNode::get(Context, Elts),
1133 NextMetadataNo);
1134 NextMetadataNo++;
1135 break;
1136 }
1137 case bitc::METADATA_LOCATION: {
1138 if (Record.size() != 5 && Record.size() != 6)
1139 return error("Invalid record");
1140
1141 IsDistinct = Record[0];
1142 unsigned Line = Record[1];
1143 unsigned Column = Record[2];
1144 Metadata *Scope = getMD(Record[3]);
1145 Metadata *InlinedAt = getMDOrNull(Record[4]);
1146 bool ImplicitCode = Record.size() == 6 && Record[5];
1147 MetadataList.assignValue(
1148 GET_OR_DISTINCT(DILocation, (Context, Line, Column, Scope, InlinedAt,
1149 ImplicitCode)),
1150 NextMetadataNo);
1151 NextMetadataNo++;
1152 break;
1153 }
1154 case bitc::METADATA_GENERIC_DEBUG: {
1155 if (Record.size() < 4)
1156 return error("Invalid record");
1157
1158 IsDistinct = Record[0];
1159 unsigned Tag = Record[1];
1160 unsigned Version = Record[2];
1161
1162 if (Tag >= 1u << 16 || Version != 0)
1163 return error("Invalid record");
1164
1165 auto *Header = getMDString(Record[3]);
1166 SmallVector<Metadata *, 8> DwarfOps;
1167 for (unsigned I = 4, E = Record.size(); I != E; ++I)
1168 DwarfOps.push_back(getMDOrNull(Record[I]));
1169 MetadataList.assignValue(
1170 GET_OR_DISTINCT(GenericDINode, (Context, Tag, Header, DwarfOps)),
1171 NextMetadataNo);
1172 NextMetadataNo++;
1173 break;
1174 }
1175 case bitc::METADATA_SUBRANGE: {
1176 Metadata *Val = nullptr;
1177 // Operand 'count' is interpreted as:
1178 // - Signed integer (version 0)
1179 // - Metadata node (version 1)
1180 switch (Record[0] >> 1) {
1181 case 0:
1182 Val = GET_OR_DISTINCT(DISubrange,
1183 (Context, Record[1], unrotateSign(Record.back())));
1184 break;
1185 case 1:
1186 Val = GET_OR_DISTINCT(DISubrange, (Context, getMDOrNull(Record[1]),
1187 unrotateSign(Record.back())));
1188 break;
1189 default:
1190 return error("Invalid record: Unsupported version of DISubrange");
1191 }
1192
1193 MetadataList.assignValue(Val, NextMetadataNo);
1194 IsDistinct = Record[0] & 1;
1195 NextMetadataNo++;
1196 break;
1197 }
1198 case bitc::METADATA_ENUMERATOR: {
1199 if (Record.size() != 3)
1200 return error("Invalid record");
1201
1202 IsDistinct = Record[0] & 1;
1203 bool IsUnsigned = Record[0] & 2;
1204 MetadataList.assignValue(
1205 GET_OR_DISTINCT(DIEnumerator, (Context, unrotateSign(Record[1]),
1206 IsUnsigned, getMDString(Record[2]))),
1207 NextMetadataNo);
1208 NextMetadataNo++;
1209 break;
1210 }
1211 case bitc::METADATA_BASIC_TYPE: {
1212 if (Record.size() < 6 || Record.size() > 7)
1213 return error("Invalid record");
1214
1215 IsDistinct = Record[0];
1216 DINode::DIFlags Flags = (Record.size() > 6) ?
1217 static_cast<DINode::DIFlags>(Record[6]) : DINode::FlagZero;
1218
1219 MetadataList.assignValue(
1220 GET_OR_DISTINCT(DIBasicType,
1221 (Context, Record[1], getMDString(Record[2]), Record[3],
1222 Record[4], Record[5], Flags)),
1223 NextMetadataNo);
1224 NextMetadataNo++;
1225 break;
1226 }
1227 case bitc::METADATA_DERIVED_TYPE: {
1228 if (Record.size() < 12 || Record.size() > 13)
1229 return error("Invalid record");
1230
1231 // DWARF address space is encoded as N->getDWARFAddressSpace() + 1. 0 means
1232 // that there is no DWARF address space associated with DIDerivedType.
1233 Optional<unsigned> DWARFAddressSpace;
1234 if (Record.size() > 12 && Record[12])
1235 DWARFAddressSpace = Record[12] - 1;
1236
1237 IsDistinct = Record[0];
1238 DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[10]);
1239 MetadataList.assignValue(
1240 GET_OR_DISTINCT(DIDerivedType,
1241 (Context, Record[1], getMDString(Record[2]),
1242 getMDOrNull(Record[3]), Record[4],
1243 getDITypeRefOrNull(Record[5]),
1244 getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1245 Record[9], DWARFAddressSpace, Flags,
1246 getDITypeRefOrNull(Record[11]))),
1247 NextMetadataNo);
1248 NextMetadataNo++;
1249 break;
1250 }
1251 case bitc::METADATA_COMPOSITE_TYPE: {
1252 if (Record.size() < 16 || Record.size() > 17)
1253 return error("Invalid record");
1254
1255 // If we have a UUID and this is not a forward declaration, lookup the
1256 // mapping.
1257 IsDistinct = Record[0] & 0x1;
1258 bool IsNotUsedInTypeRef = Record[0] >= 2;
1259 unsigned Tag = Record[1];
1260 MDString *Name = getMDString(Record[2]);
1261 Metadata *File = getMDOrNull(Record[3]);
1262 unsigned Line = Record[4];
1263 Metadata *Scope = getDITypeRefOrNull(Record[5]);
1264 Metadata *BaseType = nullptr;
1265 uint64_t SizeInBits = Record[7];
1266 if (Record[8] > (uint64_t)std::numeric_limits<uint32_t>::max())
1267 return error("Alignment value is too large");
1268 uint32_t AlignInBits = Record[8];
1269 uint64_t OffsetInBits = 0;
1270 DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[10]);
1271 Metadata *Elements = nullptr;
1272 unsigned RuntimeLang = Record[12];
1273 Metadata *VTableHolder = nullptr;
1274 Metadata *TemplateParams = nullptr;
1275 Metadata *Discriminator = nullptr;
1276 auto *Identifier = getMDString(Record[15]);
1277 // If this module is being parsed so that it can be ThinLTO imported
1278 // into another module, composite types only need to be imported
1279 // as type declarations (unless full type definitions requested).
1280 // Create type declarations up front to save memory. Also, buildODRType
1281 // handles the case where this is type ODRed with a definition needed
1282 // by the importing module, in which case the existing definition is
1283 // used.
1284 if (IsImporting && !ImportFullTypeDefinitions && Identifier &&
1285 (Tag == dwarf::DW_TAG_enumeration_type ||
1286 Tag == dwarf::DW_TAG_class_type ||
1287 Tag == dwarf::DW_TAG_structure_type ||
1288 Tag == dwarf::DW_TAG_union_type)) {
1289 Flags = Flags | DINode::FlagFwdDecl;
1290 } else {
1291 BaseType = getDITypeRefOrNull(Record[6]);
1292 OffsetInBits = Record[9];
1293 Elements = getMDOrNull(Record[11]);
1294 VTableHolder = getDITypeRefOrNull(Record[13]);
1295 TemplateParams = getMDOrNull(Record[14]);
1296 if (Record.size() > 16)
1297 Discriminator = getMDOrNull(Record[16]);
1298 }
1299 DICompositeType *CT = nullptr;
1300 if (Identifier)
1301 CT = DICompositeType::buildODRType(
1302 Context, *Identifier, Tag, Name, File, Line, Scope, BaseType,
1303 SizeInBits, AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
1304 VTableHolder, TemplateParams, Discriminator);
1305
1306 // Create a node if we didn't get a lazy ODR type.
1307 if (!CT)
1308 CT = GET_OR_DISTINCT(DICompositeType,
1309 (Context, Tag, Name, File, Line, Scope, BaseType,
1310 SizeInBits, AlignInBits, OffsetInBits, Flags,
1311 Elements, RuntimeLang, VTableHolder, TemplateParams,
1312 Identifier, Discriminator));
1313 if (!IsNotUsedInTypeRef && Identifier)
1314 MetadataList.addTypeRef(*Identifier, *cast<DICompositeType>(CT));
1315
1316 MetadataList.assignValue(CT, NextMetadataNo);
1317 NextMetadataNo++;
1318 break;
1319 }
1320 case bitc::METADATA_SUBROUTINE_TYPE: {
1321 if (Record.size() < 3 || Record.size() > 4)
1322 return error("Invalid record");
1323 bool IsOldTypeRefArray = Record[0] < 2;
1324 unsigned CC = (Record.size() > 3) ? Record[3] : 0;
1325
1326 IsDistinct = Record[0] & 0x1;
1327 DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[1]);
1328 Metadata *Types = getMDOrNull(Record[2]);
1329 if (LLVM_UNLIKELY(IsOldTypeRefArray)__builtin_expect((bool)(IsOldTypeRefArray), false))
1330 Types = MetadataList.upgradeTypeRefArray(Types);
1331
1332 MetadataList.assignValue(
1333 GET_OR_DISTINCT(DISubroutineType, (Context, Flags, CC, Types)),
1334 NextMetadataNo);
1335 NextMetadataNo++;
1336 break;
1337 }
1338
1339 case bitc::METADATA_MODULE: {
1340 if (Record.size() != 6)
1341 return error("Invalid record");
1342
1343 IsDistinct = Record[0];
1344 MetadataList.assignValue(
1345 GET_OR_DISTINCT(DIModule,
1346 (Context, getMDOrNull(Record[1]),
1347 getMDString(Record[2]), getMDString(Record[3]),
1348 getMDString(Record[4]), getMDString(Record[5]))),
1349 NextMetadataNo);
1350 NextMetadataNo++;
1351 break;
1352 }
1353
1354 case bitc::METADATA_FILE: {
1355 if (Record.size() != 3 && Record.size() != 5 && Record.size() != 6)
1356 return error("Invalid record");
1357
1358 IsDistinct = Record[0];
1359 Optional<DIFile::ChecksumInfo<MDString *>> Checksum;
1360 // The BitcodeWriter writes null bytes into Record[3:4] when the Checksum
1361 // is not present. This matches up with the old internal representation,
1362 // and the old encoding for CSK_None in the ChecksumKind. The new
1363 // representation reserves the value 0 in the ChecksumKind to continue to
1364 // encode None in a backwards-compatible way.
1365 if (Record.size() > 4 && Record[3] && Record[4])
1366 Checksum.emplace(static_cast<DIFile::ChecksumKind>(Record[3]),
1367 getMDString(Record[4]));
1368 MetadataList.assignValue(
1369 GET_OR_DISTINCT(
1370 DIFile,
1371 (Context, getMDString(Record[1]), getMDString(Record[2]), Checksum,
1372 Record.size() > 5 ? Optional<MDString *>(getMDString(Record[5]))
1373 : None)),
1374 NextMetadataNo);
1375 NextMetadataNo++;
1376 break;
1377 }
1378 case bitc::METADATA_COMPILE_UNIT: {
1379 if (Record.size() < 14 || Record.size() > 19)
1380 return error("Invalid record");
1381
1382 // Ignore Record[0], which indicates whether this compile unit is
1383 // distinct. It's always distinct.
1384 IsDistinct = true;
1385 auto *CU = DICompileUnit::getDistinct(
1386 Context, Record[1], getMDOrNull(Record[2]), getMDString(Record[3]),
1387 Record[4], getMDString(Record[5]), Record[6], getMDString(Record[7]),
1388 Record[8], getMDOrNull(Record[9]), getMDOrNull(Record[10]),
1389 getMDOrNull(Record[12]), getMDOrNull(Record[13]),
1390 Record.size() <= 15 ? nullptr : getMDOrNull(Record[15]),
1391 Record.size() <= 14 ? 0 : Record[14],
1392 Record.size() <= 16 ? true : Record[16],
1393 Record.size() <= 17 ? false : Record[17],
1394 Record.size() <= 18 ? 0 : Record[18],
1395 Record.size() <= 19 ? 0 : Record[19]);
1396
1397 MetadataList.assignValue(CU, NextMetadataNo);
1398 NextMetadataNo++;
1399
1400 // Move the Upgrade the list of subprograms.
1401 if (Metadata *SPs = getMDOrNullWithoutPlaceholders(Record[11]))
1402 CUSubprograms.push_back({CU, SPs});
1403 break;
1404 }
1405 case bitc::METADATA_SUBPROGRAM: {
1406 if (Record.size() < 18 || Record.size() > 21)
1407 return error("Invalid record");
1408
1409 bool HasSPFlags = Record[0] & 4;
1410
1411 DINode::DIFlags Flags;
1412 DISubprogram::DISPFlags SPFlags;
1413 if (!HasSPFlags)
1414 Flags = static_cast<DINode::DIFlags>(Record[11 + 2]);
1415 else {
1416 Flags = static_cast<DINode::DIFlags>(Record[11]);
1417 SPFlags = static_cast<DISubprogram::DISPFlags>(Record[9]);
1418 }
1419
1420 // Support for old metadata when
1421 // subprogram specific flags are placed in DIFlags.
1422 const unsigned DIFlagMainSubprogram = 1 << 21;
1423 bool HasOldMainSubprogramFlag = Flags & DIFlagMainSubprogram;
1424 if (HasOldMainSubprogramFlag)
1425 // Remove old DIFlagMainSubprogram from DIFlags.
1426 // Note: This assumes that any future use of bit 21 defaults to it
1427 // being 0.
1428 Flags &= ~static_cast<DINode::DIFlags>(DIFlagMainSubprogram);
1429
1430 if (HasOldMainSubprogramFlag && HasSPFlags)
1431 SPFlags |= DISubprogram::SPFlagMainSubprogram;
1432 else if (!HasSPFlags)
1433 SPFlags = DISubprogram::toSPFlags(
1434 /*IsLocalToUnit=*/Record[7], /*IsDefinition=*/Record[8],
1435 /*IsOptimized=*/Record[14], /*Virtuality=*/Record[11],
1436 /*DIFlagMainSubprogram*/HasOldMainSubprogramFlag);
1437
1438 // All definitions should be distinct.
1439 IsDistinct = (Record[0] & 1) || (SPFlags & DISubprogram::SPFlagDefinition);
1440 // Version 1 has a Function as Record[15].
1441 // Version 2 has removed Record[15].
1442 // Version 3 has the Unit as Record[15].
1443 // Version 4 added thisAdjustment.
1444 // Version 5 repacked flags into DISPFlags, changing many element numbers.
1445 bool HasUnit = Record[0] & 2;
1446 if (!HasSPFlags && HasUnit && Record.size() < 19)
1447 return error("Invalid record");
1448 if (HasSPFlags && !HasUnit)
1449 return error("Invalid record");
1450 // Accommodate older formats.
1451 bool HasFn = false;
1452 bool HasThisAdj = true;
1453 bool HasThrownTypes = true;
1454 unsigned OffsetA = 0;
1455 unsigned OffsetB = 0;
1456 if (!HasSPFlags) {
1457 OffsetA = 2;
1458 OffsetB = 2;
1459 if (Record.size() >= 19) {
1460 HasFn = !HasUnit;
1461 OffsetB++;
1462 }
1463 HasThisAdj = Record.size() >= 20;
1464 HasThrownTypes = Record.size() >= 21;
1465 }
1466 Metadata *CUorFn = getMDOrNull(Record[12 + OffsetB]);
1467 DISubprogram *SP = GET_OR_DISTINCT(
1468 DISubprogram,
1469 (Context,
1470 getDITypeRefOrNull(Record[1]), // scope
1471 getMDString(Record[2]), // name
1472 getMDString(Record[3]), // linkageName
1473 getMDOrNull(Record[4]), // file
1474 Record[5], // line
1475 getMDOrNull(Record[6]), // type
1476 Record[7 + OffsetA], // scopeLine
1477 getDITypeRefOrNull(Record[8 + OffsetA]), // containingType
1478 Record[10 + OffsetA], // virtualIndex
1479 HasThisAdj ? Record[16 + OffsetB] : 0, // thisAdjustment
1480 Flags, // flags
1481 SPFlags, // SPFlags
1482 HasUnit ? CUorFn : nullptr, // unit
1483 getMDOrNull(Record[13 + OffsetB]), // templateParams
1484 getMDOrNull(Record[14 + OffsetB]), // declaration
1485 getMDOrNull(Record[15 + OffsetB]), // retainedNodes
1486 HasThrownTypes ? getMDOrNull(Record[17 + OffsetB])
1487 : nullptr // thrownTypes
1488 ));
1489 MetadataList.assignValue(SP, NextMetadataNo);
1490 NextMetadataNo++;
1491
1492 // Upgrade sp->function mapping to function->sp mapping.
1493 if (HasFn) {
1494 if (auto *CMD = dyn_cast_or_null<ConstantAsMetadata>(CUorFn))
1495 if (auto *F = dyn_cast<Function>(CMD->getValue())) {
1496 if (F->isMaterializable())
1497 // Defer until materialized; unmaterialized functions may not have
1498 // metadata.
1499 FunctionsWithSPs[F] = SP;
1500 else if (!F->empty())
1501 F->setSubprogram(SP);
1502 }
1503 }
1504 break;
1505 }
1506 case bitc::METADATA_LEXICAL_BLOCK: {
1507 if (Record.size() != 5)
1508 return error("Invalid record");
1509
1510 IsDistinct = Record[0];
1511 MetadataList.assignValue(
1512 GET_OR_DISTINCT(DILexicalBlock,
1513 (Context, getMDOrNull(Record[1]),
1514 getMDOrNull(Record[2]), Record[3], Record[4])),
1515 NextMetadataNo);
1516 NextMetadataNo++;
1517 break;
1518 }
1519 case bitc::METADATA_LEXICAL_BLOCK_FILE: {
1520 if (Record.size() != 4)
1521 return error("Invalid record");
1522
1523 IsDistinct = Record[0];
1524 MetadataList.assignValue(
1525 GET_OR_DISTINCT(DILexicalBlockFile,
1526 (Context, getMDOrNull(Record[1]),
1527 getMDOrNull(Record[2]), Record[3])),
1528 NextMetadataNo);
1529 NextMetadataNo++;
1530 break;
1531 }
1532 case bitc::METADATA_COMMON_BLOCK: {
1533 IsDistinct = Record[0] & 1;
1534 MetadataList.assignValue(
1535 GET_OR_DISTINCT(DICommonBlock,
1536 (Context, getMDOrNull(Record[1]),
1537 getMDOrNull(Record[2]), getMDString(Record[3]),
1538 getMDOrNull(Record[4]), Record[5])),
1539 NextMetadataNo);
1540 NextMetadataNo++;
1541 break;
1542 }
1543 case bitc::METADATA_NAMESPACE: {
1544 // Newer versions of DINamespace dropped file and line.
1545 MDString *Name;
1546 if (Record.size() == 3)
1547 Name = getMDString(Record[2]);
1548 else if (Record.size() == 5)
1549 Name = getMDString(Record[3]);
1550 else
1551 return error("Invalid record");
1552
1553 IsDistinct = Record[0] & 1;
1554 bool ExportSymbols = Record[0] & 2;
1555 MetadataList.assignValue(
1556 GET_OR_DISTINCT(DINamespace,
1557 (Context, getMDOrNull(Record[1]), Name, ExportSymbols)),
1558 NextMetadataNo);
1559 NextMetadataNo++;
1560 break;
1561 }
1562 case bitc::METADATA_MACRO: {
1563 if (Record.size() != 5)
1564 return error("Invalid record");
1565
1566 IsDistinct = Record[0];
1567 MetadataList.assignValue(
1568 GET_OR_DISTINCT(DIMacro,
1569 (Context, Record[1], Record[2], getMDString(Record[3]),
1570 getMDString(Record[4]))),
1571 NextMetadataNo);
1572 NextMetadataNo++;
1573 break;
1574 }
1575 case bitc::METADATA_MACRO_FILE: {
1576 if (Record.size() != 5)
1577 return error("Invalid record");
1578
1579 IsDistinct = Record[0];
1580 MetadataList.assignValue(
1581 GET_OR_DISTINCT(DIMacroFile,
1582 (Context, Record[1], Record[2], getMDOrNull(Record[3]),
1583 getMDOrNull(Record[4]))),
1584 NextMetadataNo);
1585 NextMetadataNo++;
1586 break;
1587 }
1588 case bitc::METADATA_TEMPLATE_TYPE: {
1589 if (Record.size() != 3)
1590 return error("Invalid record");
1591
1592 IsDistinct = Record[0];
1593 MetadataList.assignValue(GET_OR_DISTINCT(DITemplateTypeParameter,
1594 (Context, getMDString(Record[1]),
1595 getDITypeRefOrNull(Record[2]))),
1596 NextMetadataNo);
1597 NextMetadataNo++;
1598 break;
1599 }
1600 case bitc::METADATA_TEMPLATE_VALUE: {
1601 if (Record.size() != 5)
1602 return error("Invalid record");
1603
1604 IsDistinct = Record[0];
1605 MetadataList.assignValue(
1606 GET_OR_DISTINCT(DITemplateValueParameter,
1607 (Context, Record[1], getMDString(Record[2]),
1608 getDITypeRefOrNull(Record[3]),
1609 getMDOrNull(Record[4]))),
1610 NextMetadataNo);
1611 NextMetadataNo++;
1612 break;
1613 }
1614 case bitc::METADATA_GLOBAL_VAR: {
1615 if (Record.size() < 11 || Record.size() > 13)
1616 return error("Invalid record");
1617
1618 IsDistinct = Record[0] & 1;
1619 unsigned Version = Record[0] >> 1;
1620
1621 if (Version == 2) {
1622 MetadataList.assignValue(
1623 GET_OR_DISTINCT(
1624 DIGlobalVariable,
1625 (Context, getMDOrNull(Record[1]), getMDString(Record[2]),
1626 getMDString(Record[3]), getMDOrNull(Record[4]), Record[5],
1627 getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1628 getMDOrNull(Record[9]), getMDOrNull(Record[10]), Record[11])),
1629 NextMetadataNo);
1630
1631 NextMetadataNo++;
1632 } else if (Version == 1) {
1633 // No upgrade necessary. A null field will be introduced to indicate
1634 // that no parameter information is available.
1635 MetadataList.assignValue(
1636 GET_OR_DISTINCT(DIGlobalVariable,
1637 (Context, getMDOrNull(Record[1]),
1638 getMDString(Record[2]), getMDString(Record[3]),
1639 getMDOrNull(Record[4]), Record[5],
1640 getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1641 getMDOrNull(Record[10]), nullptr, Record[11])),
1642 NextMetadataNo);
1643
1644 NextMetadataNo++;
1645 } else if (Version == 0) {
1646 // Upgrade old metadata, which stored a global variable reference or a
1647 // ConstantInt here.
1648 NeedUpgradeToDIGlobalVariableExpression = true;
1649 Metadata *Expr = getMDOrNull(Record[9]);
1650 uint32_t AlignInBits = 0;
1651 if (Record.size() > 11) {
1652 if (Record[11] > (uint64_t)std::numeric_limits<uint32_t>::max())
1653 return error("Alignment value is too large");
1654 AlignInBits = Record[11];
1655 }
1656 GlobalVariable *Attach = nullptr;
1657 if (auto *CMD = dyn_cast_or_null<ConstantAsMetadata>(Expr)) {
1658 if (auto *GV = dyn_cast<GlobalVariable>(CMD->getValue())) {
1659 Attach = GV;
1660 Expr = nullptr;
1661 } else if (auto *CI = dyn_cast<ConstantInt>(CMD->getValue())) {
1662 Expr = DIExpression::get(Context,
1663 {dwarf::DW_OP_constu, CI->getZExtValue(),
1664 dwarf::DW_OP_stack_value});
1665 } else {
1666 Expr = nullptr;
1667 }
1668 }
1669 DIGlobalVariable *DGV = GET_OR_DISTINCT(
1670 DIGlobalVariable,
1671 (Context, getMDOrNull(Record[1]), getMDString(Record[2]),
1672 getMDString(Record[3]), getMDOrNull(Record[4]), Record[5],
1673 getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1674 getMDOrNull(Record[10]), nullptr, AlignInBits));
1675
1676 DIGlobalVariableExpression *DGVE = nullptr;
1677 if (Attach || Expr)
1678 DGVE = DIGlobalVariableExpression::getDistinct(
1679 Context, DGV, Expr ? Expr : DIExpression::get(Context, {}));
1680 if (Attach)
1681 Attach->addDebugInfo(DGVE);
1682
1683 auto *MDNode = Expr ? cast<Metadata>(DGVE) : cast<Metadata>(DGV);
1684 MetadataList.assignValue(MDNode, NextMetadataNo);
1685 NextMetadataNo++;
1686 } else
1687 return error("Invalid record");
1688
1689 break;
1690 }
1691 case bitc::METADATA_LOCAL_VAR: {
1692 // 10th field is for the obseleted 'inlinedAt:' field.
1693 if (Record.size() < 8 || Record.size() > 10)
1694 return error("Invalid record");
1695
1696 IsDistinct = Record[0] & 1;
1697 bool HasAlignment = Record[0] & 2;
1698 // 2nd field used to be an artificial tag, either DW_TAG_auto_variable or
1699 // DW_TAG_arg_variable, if we have alignment flag encoded it means, that
1700 // this is newer version of record which doesn't have artificial tag.
1701 bool HasTag = !HasAlignment && Record.size() > 8;
1702 DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[7 + HasTag]);
1703 uint32_t AlignInBits = 0;
1704 if (HasAlignment) {
1705 if (Record[8 + HasTag] > (uint64_t)std::numeric_limits<uint32_t>::max())
1706 return error("Alignment value is too large");
1707 AlignInBits = Record[8 + HasTag];
1708 }
1709 MetadataList.assignValue(
1710 GET_OR_DISTINCT(DILocalVariable,
1711 (Context, getMDOrNull(Record[1 + HasTag]),
1712 getMDString(Record[2 + HasTag]),
1713 getMDOrNull(Record[3 + HasTag]), Record[4 + HasTag],
1714 getDITypeRefOrNull(Record[5 + HasTag]),
1715 Record[6 + HasTag], Flags, AlignInBits)),
1716 NextMetadataNo);
1717 NextMetadataNo++;
1718 break;
1719 }
1720 case bitc::METADATA_LABEL: {
1721 if (Record.size() != 5)
1722 return error("Invalid record");
1723
1724 IsDistinct = Record[0] & 1;
1725 MetadataList.assignValue(
1726 GET_OR_DISTINCT(DILabel,
1727 (Context, getMDOrNull(Record[1]),
1728 getMDString(Record[2]),
1729 getMDOrNull(Record[3]), Record[4])),
1730 NextMetadataNo);
1731 NextMetadataNo++;
1732 break;
1733 }
1734 case bitc::METADATA_EXPRESSION: {
1735 if (Record.size() < 1)
1736 return error("Invalid record");
1737
1738 IsDistinct = Record[0] & 1;
1739 uint64_t Version = Record[0] >> 1;
1740 auto Elts = MutableArrayRef<uint64_t>(Record).slice(1);
1741
1742 SmallVector<uint64_t, 6> Buffer;
1743 if (Error Err = upgradeDIExpression(Version, Elts, Buffer))
1744 return Err;
1745
1746 MetadataList.assignValue(
1747 GET_OR_DISTINCT(DIExpression, (Context, Elts)), NextMetadataNo);
1748 NextMetadataNo++;
1749 break;
1750 }
1751 case bitc::METADATA_GLOBAL_VAR_EXPR: {
1752 if (Record.size() != 3)
1753 return error("Invalid record");
1754
1755 IsDistinct = Record[0];
1756 Metadata *Expr = getMDOrNull(Record[2]);
1757 if (!Expr)
1758 Expr = DIExpression::get(Context, {});
1759 MetadataList.assignValue(
1760 GET_OR_DISTINCT(DIGlobalVariableExpression,
1761 (Context, getMDOrNull(Record[1]), Expr)),
1762 NextMetadataNo);
1763 NextMetadataNo++;
1764 break;
1765 }
1766 case bitc::METADATA_OBJC_PROPERTY: {
1767 if (Record.size() != 8)
1768 return error("Invalid record");
1769
1770 IsDistinct = Record[0];
1771 MetadataList.assignValue(
1772 GET_OR_DISTINCT(DIObjCProperty,
1773 (Context, getMDString(Record[1]),
1774 getMDOrNull(Record[2]), Record[3],
1775 getMDString(Record[4]), getMDString(Record[5]),
1776 Record[6], getDITypeRefOrNull(Record[7]))),
1777 NextMetadataNo);
1778 NextMetadataNo++;
1779 break;
1780 }
1781 case bitc::METADATA_IMPORTED_ENTITY: {
1782 if (Record.size() != 6 && Record.size() != 7)
1783 return error("Invalid record");
1784
1785 IsDistinct = Record[0];
1786 bool HasFile = (Record.size() == 7);
1787 MetadataList.assignValue(
1788 GET_OR_DISTINCT(DIImportedEntity,
1789 (Context, Record[1], getMDOrNull(Record[2]),
1790 getDITypeRefOrNull(Record[3]),
1791 HasFile ? getMDOrNull(Record[6]) : nullptr,
1792 HasFile ? Record[4] : 0, getMDString(Record[5]))),
1793 NextMetadataNo);
1794 NextMetadataNo++;
1795 break;
1796 }
1797 case bitc::METADATA_STRING_OLD: {
1798 std::string String(Record.begin(), Record.end());
1799
1800 // Test for upgrading !llvm.loop.
1801 HasSeenOldLoopTags |= mayBeOldLoopAttachmentTag(String);
1802 ++NumMDStringLoaded;
1803 Metadata *MD = MDString::get(Context, String);
1804 MetadataList.assignValue(MD, NextMetadataNo);
1805 NextMetadataNo++;
1806 break;
1807 }
1808 case bitc::METADATA_STRINGS: {
1809 auto CreateNextMDString = [&](StringRef Str) {
1810 ++NumMDStringLoaded;
1811 MetadataList.assignValue(MDString::get(Context, Str), NextMetadataNo);
1812 NextMetadataNo++;
1813 };
1814 if (Error Err = parseMetadataStrings(Record, Blob, CreateNextMDString))
1815 return Err;
1816 break;
1817 }
1818 case bitc::METADATA_GLOBAL_DECL_ATTACHMENT: {
1819 if (Record.size() % 2 == 0)
1820 return error("Invalid record");
1821 unsigned ValueID = Record[0];
1822 if (ValueID >= ValueList.size())
1823 return error("Invalid record");
1824 if (auto *GO = dyn_cast<GlobalObject>(ValueList[ValueID]))
1825 if (Error Err = parseGlobalObjectAttachment(
1826 *GO, ArrayRef<uint64_t>(Record).slice(1)))
1827 return Err;
1828 break;
1829 }
1830 case bitc::METADATA_KIND: {
1831 // Support older bitcode files that had METADATA_KIND records in a
1832 // block with METADATA_BLOCK_ID.
1833 if (Error Err = parseMetadataKindRecord(Record))
1834 return Err;
1835 break;
1836 }
1837 }
1838 return Error::success();
1839#undef GET_OR_DISTINCT
1840}
1841
1842Error MetadataLoader::MetadataLoaderImpl::parseMetadataStrings(
1843 ArrayRef<uint64_t> Record, StringRef Blob,
1844 function_ref<void(StringRef)> CallBack) {
1845 // All the MDStrings in the block are emitted together in a single
1846 // record. The strings are concatenated and stored in a blob along with
1847 // their sizes.
1848 if (Record.size() != 2)
1849 return error("Invalid record: metadata strings layout");
1850
1851 unsigned NumStrings = Record[0];
1852 unsigned StringsOffset = Record[1];
1853 if (!NumStrings)
1854 return error("Invalid record: metadata strings with no strings");
1855 if (StringsOffset > Blob.size())
1856 return error("Invalid record: metadata strings corrupt offset");
1857
1858 StringRef Lengths = Blob.slice(0, StringsOffset);
1859 SimpleBitstreamCursor R(Lengths);
1860
1861 StringRef Strings = Blob.drop_front(StringsOffset);
1862 do {
1863 if (R.AtEndOfStream())
1864 return error("Invalid record: metadata strings bad length");
1865
1866 unsigned Size = R.ReadVBR(6);
1867 if (Strings.size() < Size)
1868 return error("Invalid record: metadata strings truncated chars");
1869
1870 CallBack(Strings.slice(0, Size));
1871 Strings = Strings.drop_front(Size);
1872 } while (--NumStrings);
1873
1874 return Error::success();
1875}
1876
1877Error MetadataLoader::MetadataLoaderImpl::parseGlobalObjectAttachment(
1878 GlobalObject &GO, ArrayRef<uint64_t> Record) {
1879 assert(Record.size() % 2 == 0)((Record.size() % 2 == 0) ? static_cast<void> (0) : __assert_fail
("Record.size() % 2 == 0", "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 1879, __PRETTY_FUNCTION__))
;
1880 for (unsigned I = 0, E = Record.size(); I != E; I += 2) {
1881 auto K = MDKindMap.find(Record[I]);
1882 if (K == MDKindMap.end())
1883 return error("Invalid ID");
1884 MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[I + 1]);
1885 if (!MD)
1886 return error("Invalid metadata attachment: expect fwd ref to MDNode");
1887 GO.addMetadata(K->second, *MD);
1888 }
1889 return Error::success();
1890}
1891
1892/// Parse metadata attachments.
1893Error MetadataLoader::MetadataLoaderImpl::parseMetadataAttachment(
1894 Function &F, const SmallVectorImpl<Instruction *> &InstructionList) {
1895 if (Stream.EnterSubBlock(bitc::METADATA_ATTACHMENT_ID))
2
Assuming the condition is true
3
Taking true branch
1896 return error("Invalid record");
4
Calling 'error'
1897
1898 SmallVector<uint64_t, 64> Record;
1899 PlaceholderQueue Placeholders;
1900
1901 while (true) {
1902 BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
1903
1904 switch (Entry.Kind) {
1905 case BitstreamEntry::SubBlock: // Handled for us already.
1906 case BitstreamEntry::Error:
1907 return error("Malformed block");
1908 case BitstreamEntry::EndBlock:
1909 resolveForwardRefsAndPlaceholders(Placeholders);
1910 return Error::success();
1911 case BitstreamEntry::Record:
1912 // The interesting case.
1913 break;
1914 }
1915
1916 // Read a metadata attachment record.
1917 Record.clear();
1918 ++NumMDRecordLoaded;
1919 switch (Stream.readRecord(Entry.ID, Record)) {
1920 default: // Default behavior: ignore.
1921 break;
1922 case bitc::METADATA_ATTACHMENT: {
1923 unsigned RecordLength = Record.size();
1924 if (Record.empty())
1925 return error("Invalid record");
1926 if (RecordLength % 2 == 0) {
1927 // A function attachment.
1928 if (Error Err = parseGlobalObjectAttachment(F, Record))
1929 return Err;
1930 continue;
1931 }
1932
1933 // An instruction attachment.
1934 Instruction *Inst = InstructionList[Record[0]];
1935 for (unsigned i = 1; i != RecordLength; i = i + 2) {
1936 unsigned Kind = Record[i];
1937 DenseMap<unsigned, unsigned>::iterator I = MDKindMap.find(Kind);
1938 if (I == MDKindMap.end())
1939 return error("Invalid ID");
1940 if (I->second == LLVMContext::MD_tbaa && StripTBAA)
1941 continue;
1942
1943 auto Idx = Record[i + 1];
1944 if (Idx < (MDStringRef.size() + GlobalMetadataBitPosIndex.size()) &&
1945 !MetadataList.lookup(Idx)) {
1946 // Load the attachment if it is in the lazy-loadable range and hasn't
1947 // been loaded yet.
1948 lazyLoadOneMetadata(Idx, Placeholders);
1949 resolveForwardRefsAndPlaceholders(Placeholders);
1950 }
1951
1952 Metadata *Node = MetadataList.getMetadataFwdRef(Idx);
1953 if (isa<LocalAsMetadata>(Node))
1954 // Drop the attachment. This used to be legal, but there's no
1955 // upgrade path.
1956 break;
1957 MDNode *MD = dyn_cast_or_null<MDNode>(Node);
1958 if (!MD)
1959 return error("Invalid metadata attachment");
1960
1961 if (HasSeenOldLoopTags && I->second == LLVMContext::MD_loop)
1962 MD = upgradeInstructionLoopAttachment(*MD);
1963
1964 if (I->second == LLVMContext::MD_tbaa) {
1965 assert(!MD->isTemporary() && "should load MDs before attachments")((!MD->isTemporary() && "should load MDs before attachments"
) ? static_cast<void> (0) : __assert_fail ("!MD->isTemporary() && \"should load MDs before attachments\""
, "/build/llvm-toolchain-snapshot-9~svn362543/lib/Bitcode/Reader/MetadataLoader.cpp"
, 1965, __PRETTY_FUNCTION__))
;
1966 MD = UpgradeTBAANode(*MD);
1967 }
1968 Inst->setMetadata(I->second, MD);
1969 }
1970 break;
1971 }
1972 }
1973 }
1974}
1975
1976/// Parse a single METADATA_KIND record, inserting result in MDKindMap.
1977Error MetadataLoader::MetadataLoaderImpl::parseMetadataKindRecord(
1978 SmallVectorImpl<uint64_t> &Record) {
1979 if (Record.size() < 2)
1980 return error("Invalid record");
1981
1982 unsigned Kind = Record[0];
1983 SmallString<8> Name(Record.begin() + 1, Record.end());
1984
1985 unsigned NewKind = TheModule.getMDKindID(Name.str());
1986 if (!MDKindMap.insert(std::make_pair(Kind, NewKind)).second)
1987 return error("Conflicting METADATA_KIND records");
1988 return Error::success();
1989}
1990
1991/// Parse the metadata kinds out of the METADATA_KIND_BLOCK.
1992Error MetadataLoader::MetadataLoaderImpl::parseMetadataKinds() {
1993 if (Stream.EnterSubBlock(bitc::METADATA_KIND_BLOCK_ID))
1994 return error("Invalid record");
1995
1996 SmallVector<uint64_t, 64> Record;
1997
1998 // Read all the records.
1999 while (true) {
2000 BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
2001
2002 switch (Entry.Kind) {
2003 case BitstreamEntry::SubBlock: // Handled for us already.
2004 case BitstreamEntry::Error:
2005 return error("Malformed block");
2006 case BitstreamEntry::EndBlock:
2007 return Error::success();
2008 case BitstreamEntry::Record:
2009 // The interesting case.
2010 break;
2011 }
2012
2013 // Read a record.
2014 Record.clear();
2015 ++NumMDRecordLoaded;
2016 unsigned Code = Stream.readRecord(Entry.ID, Record);
2017 switch (Code) {
2018 default: // Default behavior: ignore.
2019 break;
2020 case bitc::METADATA_KIND: {
2021 if (Error Err = parseMetadataKindRecord(Record))
2022 return Err;
2023 break;
2024 }
2025 }
2026 }
2027}
2028
2029MetadataLoader &MetadataLoader::operator=(MetadataLoader &&RHS) {
2030 Pimpl = std::move(RHS.Pimpl);
2031 return *this;
2032}
2033MetadataLoader::MetadataLoader(MetadataLoader &&RHS)
2034 : Pimpl(std::move(RHS.Pimpl)) {}
2035
2036MetadataLoader::~MetadataLoader() = default;
2037MetadataLoader::MetadataLoader(BitstreamCursor &Stream, Module &TheModule,
2038 BitcodeReaderValueList &ValueList,
2039 bool IsImporting,
2040 std::function<Type *(unsigned)> getTypeByID)
2041 : Pimpl(llvm::make_unique<MetadataLoaderImpl>(
2042 Stream, TheModule, ValueList, std::move(getTypeByID), IsImporting)) {}
2043
2044Error MetadataLoader::parseMetadata(bool ModuleLevel) {
2045 return Pimpl->parseMetadata(ModuleLevel);
2046}
2047
2048bool MetadataLoader::hasFwdRefs() const { return Pimpl->hasFwdRefs(); }
2049
2050/// Return the given metadata, creating a replaceable forward reference if
2051/// necessary.
2052Metadata *MetadataLoader::getMetadataFwdRefOrLoad(unsigned Idx) {
2053 return Pimpl->getMetadataFwdRefOrLoad(Idx);
2054}
2055
2056DISubprogram *MetadataLoader::lookupSubprogramForFunction(Function *F) {
2057 return Pimpl->lookupSubprogramForFunction(F);
2058}
2059
2060Error MetadataLoader::parseMetadataAttachment(
2061 Function &F, const SmallVectorImpl<Instruction *> &InstructionList) {
2062 return Pimpl->parseMetadataAttachment(F, InstructionList);
1
Calling 'MetadataLoaderImpl::parseMetadataAttachment'
2063}
2064
2065Error MetadataLoader::parseMetadataKinds() {
2066 return Pimpl->parseMetadataKinds();
2067}
2068
2069void MetadataLoader::setStripTBAA(bool StripTBAA) {
2070 return Pimpl->setStripTBAA(StripTBAA);
2071}
2072
2073bool MetadataLoader::isStrippingTBAA() { return Pimpl->isStrippingTBAA(); }
2074
2075unsigned MetadataLoader::size() const { return Pimpl->size(); }
2076void MetadataLoader::shrinkTo(unsigned N) { return Pimpl->shrinkTo(N); }
2077
2078void MetadataLoader::upgradeDebugIntrinsics(Function &F) {
2079 return Pimpl->upgradeDebugIntrinsics(F);
2080}

/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h

1//===- llvm/Support/Error.h - Recoverable error handling --------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines an API used to report recoverable errors.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_SUPPORT_ERROR_H
14#define LLVM_SUPPORT_ERROR_H
15
16#include "llvm-c/Error.h"
17#include "llvm/ADT/STLExtras.h"
18#include "llvm/ADT/SmallVector.h"
19#include "llvm/ADT/StringExtras.h"
20#include "llvm/ADT/Twine.h"
21#include "llvm/Config/abi-breaking.h"
22#include "llvm/Support/AlignOf.h"
23#include "llvm/Support/Compiler.h"
24#include "llvm/Support/Debug.h"
25#include "llvm/Support/ErrorHandling.h"
26#include "llvm/Support/ErrorOr.h"
27#include "llvm/Support/Format.h"
28#include "llvm/Support/raw_ostream.h"
29#include <algorithm>
30#include <cassert>
31#include <cstdint>
32#include <cstdlib>
33#include <functional>
34#include <memory>
35#include <new>
36#include <string>
37#include <system_error>
38#include <type_traits>
39#include <utility>
40#include <vector>
41
42namespace llvm {
43
44class ErrorSuccess;
45
46/// Base class for error info classes. Do not extend this directly: Extend
47/// the ErrorInfo template subclass instead.
48class ErrorInfoBase {
49public:
50 virtual ~ErrorInfoBase() = default;
51
52 /// Print an error message to an output stream.
53 virtual void log(raw_ostream &OS) const = 0;
54
55 /// Return the error message as a string.
56 virtual std::string message() const {
57 std::string Msg;
58 raw_string_ostream OS(Msg);
59 log(OS);
60 return OS.str();
61 }
62
63 /// Convert this error to a std::error_code.
64 ///
65 /// This is a temporary crutch to enable interaction with code still
66 /// using std::error_code. It will be removed in the future.
67 virtual std::error_code convertToErrorCode() const = 0;
68
69 // Returns the class ID for this type.
70 static const void *classID() { return &ID; }
71
72 // Returns the class ID for the dynamic type of this ErrorInfoBase instance.
73 virtual const void *dynamicClassID() const = 0;
74
75 // Check whether this instance is a subclass of the class identified by
76 // ClassID.
77 virtual bool isA(const void *const ClassID) const {
78 return ClassID == classID();
79 }
80
81 // Check whether this instance is a subclass of ErrorInfoT.
82 template <typename ErrorInfoT> bool isA() const {
83 return isA(ErrorInfoT::classID());
84 }
85
86private:
87 virtual void anchor();
88
89 static char ID;
90};
91
92/// Lightweight error class with error context and mandatory checking.
93///
94/// Instances of this class wrap a ErrorInfoBase pointer. Failure states
95/// are represented by setting the pointer to a ErrorInfoBase subclass
96/// instance containing information describing the failure. Success is
97/// represented by a null pointer value.
98///
99/// Instances of Error also contains a 'Checked' flag, which must be set
100/// before the destructor is called, otherwise the destructor will trigger a
101/// runtime error. This enforces at runtime the requirement that all Error
102/// instances be checked or returned to the caller.
103///
104/// There are two ways to set the checked flag, depending on what state the
105/// Error instance is in. For Error instances indicating success, it
106/// is sufficient to invoke the boolean conversion operator. E.g.:
107///
108/// @code{.cpp}
109/// Error foo(<...>);
110///
111/// if (auto E = foo(<...>))
112/// return E; // <- Return E if it is in the error state.
113/// // We have verified that E was in the success state. It can now be safely
114/// // destroyed.
115/// @endcode
116///
117/// A success value *can not* be dropped. For example, just calling 'foo(<...>)'
118/// without testing the return value will raise a runtime error, even if foo
119/// returns success.
120///
121/// For Error instances representing failure, you must use either the
122/// handleErrors or handleAllErrors function with a typed handler. E.g.:
123///
124/// @code{.cpp}
125/// class MyErrorInfo : public ErrorInfo<MyErrorInfo> {
126/// // Custom error info.
127/// };
128///
129/// Error foo(<...>) { return make_error<MyErrorInfo>(...); }
130///
131/// auto E = foo(<...>); // <- foo returns failure with MyErrorInfo.
132/// auto NewE =
133/// handleErrors(E,
134/// [](const MyErrorInfo &M) {
135/// // Deal with the error.
136/// },
137/// [](std::unique_ptr<OtherError> M) -> Error {
138/// if (canHandle(*M)) {
139/// // handle error.
140/// return Error::success();
141/// }
142/// // Couldn't handle this error instance. Pass it up the stack.
143/// return Error(std::move(M));
144/// );
145/// // Note - we must check or return NewE in case any of the handlers
146/// // returned a new error.
147/// @endcode
148///
149/// The handleAllErrors function is identical to handleErrors, except
150/// that it has a void return type, and requires all errors to be handled and
151/// no new errors be returned. It prevents errors (assuming they can all be
152/// handled) from having to be bubbled all the way to the top-level.
153///
154/// *All* Error instances must be checked before destruction, even if
155/// they're moved-assigned or constructed from Success values that have already
156/// been checked. This enforces checking through all levels of the call stack.
157class LLVM_NODISCARD[[clang::warn_unused_result]] Error {
158 // Both ErrorList and FileError need to be able to yank ErrorInfoBase
159 // pointers out of this class to add to the error list.
160 friend class ErrorList;
161 friend class FileError;
162
163 // handleErrors needs to be able to set the Checked flag.
164 template <typename... HandlerTs>
165 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
166
167 // Expected<T> needs to be able to steal the payload when constructed from an
168 // error.
169 template <typename T> friend class Expected;
170
171 // wrap needs to be able to steal the payload.
172 friend LLVMErrorRef wrap(Error);
173
174protected:
175 /// Create a success value. Prefer using 'Error::success()' for readability
176 Error() {
177 setPtr(nullptr);
178 setChecked(false);
179 }
180
181public:
182 /// Create a success value.
183 static ErrorSuccess success();
184
185 // Errors are not copy-constructable.
186 Error(const Error &Other) = delete;
187
188 /// Move-construct an error value. The newly constructed error is considered
189 /// unchecked, even if the source error had been checked. The original error
190 /// becomes a checked Success value, regardless of its original state.
191 Error(Error &&Other) {
192 setChecked(true);
193 *this = std::move(Other);
194 }
195
196 /// Create an error value. Prefer using the 'make_error' function, but
197 /// this constructor can be useful when "re-throwing" errors from handlers.
198 Error(std::unique_ptr<ErrorInfoBase> Payload) {
199 setPtr(Payload.release());
200 setChecked(false);
10
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'
201 }
202
203 // Errors are not copy-assignable.
204 Error &operator=(const Error &Other) = delete;
205
206 /// Move-assign an error value. The current error must represent success, you
207 /// you cannot overwrite an unhandled error. The current error is then
208 /// considered unchecked. The source error becomes a checked success value,
209 /// regardless of its original state.
210 Error &operator=(Error &&Other) {
211 // Don't allow overwriting of unchecked values.
212 assertIsChecked();
213 setPtr(Other.getPtr());
214
215 // This Error is unchecked, even if the source error was checked.
216 setChecked(false);
217
218 // Null out Other's payload and set its checked bit.
219 Other.setPtr(nullptr);
220 Other.setChecked(true);
221
222 return *this;
223 }
224
225 /// Destroy a Error. Fails with a call to abort() if the error is
226 /// unchecked.
227 ~Error() {
228 assertIsChecked();
229 delete getPtr();
230 }
231
232 /// Bool conversion. Returns true if this Error is in a failure state,
233 /// and false if it is in an accept state. If the error is in a Success state
234 /// it will be considered checked.
235 explicit operator bool() {
236 setChecked(getPtr() == nullptr);
237 return getPtr() != nullptr;
238 }
239
240 /// Check whether one error is a subclass of another.
241 template <typename ErrT> bool isA() const {
242 return getPtr() && getPtr()->isA(ErrT::classID());
243 }
244
245 /// Returns the dynamic class id of this error, or null if this is a success
246 /// value.
247 const void* dynamicClassID() const {
248 if (!getPtr())
249 return nullptr;
250 return getPtr()->dynamicClassID();
251 }
252
253private:
254#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
255 // assertIsChecked() happens very frequently, but under normal circumstances
256 // is supposed to be a no-op. So we want it to be inlined, but having a bunch
257 // of debug prints can cause the function to be too large for inlining. So
258 // it's important that we define this function out of line so that it can't be
259 // inlined.
260 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
261 void fatalUncheckedError() const;
262#endif
263
264 void assertIsChecked() {
265#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
266 if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false))
267 fatalUncheckedError();
268#endif
269 }
270
271 ErrorInfoBase *getPtr() const {
272 return reinterpret_cast<ErrorInfoBase*>(
273 reinterpret_cast<uintptr_t>(Payload) &
274 ~static_cast<uintptr_t>(0x1));
275 }
276
277 void setPtr(ErrorInfoBase *EI) {
278#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
279 Payload = reinterpret_cast<ErrorInfoBase*>(
280 (reinterpret_cast<uintptr_t>(EI) &
281 ~static_cast<uintptr_t>(0x1)) |
282 (reinterpret_cast<uintptr_t>(Payload) & 0x1));
283#else
284 Payload = EI;
285#endif
286 }
287
288 bool getChecked() const {
289#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
290 return (reinterpret_cast<uintptr_t>(Payload) & 0x1) == 0;
291#else
292 return true;
293#endif
294 }
295
296 void setChecked(bool V) {
297 Payload = reinterpret_cast<ErrorInfoBase*>(
298 (reinterpret_cast<uintptr_t>(Payload) &
299 ~static_cast<uintptr_t>(0x1)) |
300 (V ? 0 : 1));
301 }
302
303 std::unique_ptr<ErrorInfoBase> takePayload() {
304 std::unique_ptr<ErrorInfoBase> Tmp(getPtr());
305 setPtr(nullptr);
306 setChecked(true);
307 return Tmp;
308 }
309
310 friend raw_ostream &operator<<(raw_ostream &OS, const Error &E) {
311 if (auto P = E.getPtr())
312 P->log(OS);
313 else
314 OS << "success";
315 return OS;
316 }
317
318 ErrorInfoBase *Payload = nullptr;
319};
320
321/// Subclass of Error for the sole purpose of identifying the success path in
322/// the type system. This allows to catch invalid conversion to Expected<T> at
323/// compile time.
324class ErrorSuccess final : public Error {};
325
326inline ErrorSuccess Error::success() { return ErrorSuccess(); }
327
328/// Make a Error instance representing failure using the given error info
329/// type.
330template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) {
331 return Error(llvm::make_unique<ErrT>(std::forward<ArgTs>(Args)...));
6
Calling 'make_unique<llvm::StringError, const llvm::Twine &, std::error_code>'
8
Returned allocated memory
9
Calling constructor for 'Error'
332}
333
334/// Base class for user error types. Users should declare their error types
335/// like:
336///
337/// class MyError : public ErrorInfo<MyError> {
338/// ....
339/// };
340///
341/// This class provides an implementation of the ErrorInfoBase::kind
342/// method, which is used by the Error RTTI system.
343template <typename ThisErrT, typename ParentErrT = ErrorInfoBase>
344class ErrorInfo : public ParentErrT {
345public:
346 using ParentErrT::ParentErrT; // inherit constructors
347
348 static const void *classID() { return &ThisErrT::ID; }
349
350 const void *dynamicClassID() const override { return &ThisErrT::ID; }
351
352 bool isA(const void *const ClassID) const override {
353 return ClassID == classID() || ParentErrT::isA(ClassID);
354 }
355};
356
357/// Special ErrorInfo subclass representing a list of ErrorInfos.
358/// Instances of this class are constructed by joinError.
359class ErrorList final : public ErrorInfo<ErrorList> {
360 // handleErrors needs to be able to iterate the payload list of an
361 // ErrorList.
362 template <typename... HandlerTs>
363 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
364
365 // joinErrors is implemented in terms of join.
366 friend Error joinErrors(Error, Error);
367
368public:
369 void log(raw_ostream &OS) const override {
370 OS << "Multiple errors:\n";
371 for (auto &ErrPayload : Payloads) {
372 ErrPayload->log(OS);
373 OS << "\n";
374 }
375 }
376
377 std::error_code convertToErrorCode() const override;
378
379 // Used by ErrorInfo::classID.
380 static char ID;
381
382private:
383 ErrorList(std::unique_ptr<ErrorInfoBase> Payload1,
384 std::unique_ptr<ErrorInfoBase> Payload2) {
385 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-9~svn362543/include/llvm/Support/Error.h"
, 386, __PRETTY_FUNCTION__))
386 "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-9~svn362543/include/llvm/Support/Error.h"
, 386, __PRETTY_FUNCTION__))
;
387 Payloads.push_back(std::move(Payload1));
388 Payloads.push_back(std::move(Payload2));
389 }
390
391 static Error join(Error E1, Error E2) {
392 if (!E1)
393 return E2;
394 if (!E2)
395 return E1;
396 if (E1.isA<ErrorList>()) {
397 auto &E1List = static_cast<ErrorList &>(*E1.getPtr());
398 if (E2.isA<ErrorList>()) {
399 auto E2Payload = E2.takePayload();
400 auto &E2List = static_cast<ErrorList &>(*E2Payload);
401 for (auto &Payload : E2List.Payloads)
402 E1List.Payloads.push_back(std::move(Payload));
403 } else
404 E1List.Payloads.push_back(E2.takePayload());
405
406 return E1;
407 }
408 if (E2.isA<ErrorList>()) {
409 auto &E2List = static_cast<ErrorList &>(*E2.getPtr());
410 E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload());
411 return E2;
412 }
413 return Error(std::unique_ptr<ErrorList>(
414 new ErrorList(E1.takePayload(), E2.takePayload())));
415 }
416
417 std::vector<std::unique_ptr<ErrorInfoBase>> Payloads;
418};
419
420/// Concatenate errors. The resulting Error is unchecked, and contains the
421/// ErrorInfo(s), if any, contained in E1, followed by the
422/// ErrorInfo(s), if any, contained in E2.
423inline Error joinErrors(Error E1, Error E2) {
424 return ErrorList::join(std::move(E1), std::move(E2));
425}
426
427/// Tagged union holding either a T or a Error.
428///
429/// This class parallels ErrorOr, but replaces error_code with Error. Since
430/// Error cannot be copied, this class replaces getError() with
431/// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the
432/// error class type.
433template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected {
434 template <class T1> friend class ExpectedAsOutParameter;
435 template <class OtherT> friend class Expected;
436
437 static const bool isRef = std::is_reference<T>::value;
438
439 using wrap = std::reference_wrapper<typename std::remove_reference<T>::type>;
440
441 using error_type = std::unique_ptr<ErrorInfoBase>;
442
443public:
444 using storage_type = typename std::conditional<isRef, wrap, T>::type;
445 using value_type = T;
446
447private:
448 using reference = typename std::remove_reference<T>::type &;
449 using const_reference = const typename std::remove_reference<T>::type &;
450 using pointer = typename std::remove_reference<T>::type *;
451 using const_pointer = const typename std::remove_reference<T>::type *;
452
453public:
454 /// Create an Expected<T> error value from the given Error.
455 Expected(Error Err)
456 : HasError(true)
457#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
458 // Expected is unchecked upon construction in Debug builds.
459 , Unchecked(true)
460#endif
461 {
462 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-9~svn362543/include/llvm/Support/Error.h"
, 462, __PRETTY_FUNCTION__))
;
463 new (getErrorStorage()) error_type(Err.takePayload());
464 }
465
466 /// Forbid to convert from Error::success() implicitly, this avoids having
467 /// Expected<T> foo() { return Error::success(); } which compiles otherwise
468 /// but triggers the assertion above.
469 Expected(ErrorSuccess) = delete;
470
471 /// Create an Expected<T> success value from the given OtherT value, which
472 /// must be convertible to T.
473 template <typename OtherT>
474 Expected(OtherT &&Val,
475 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
476 * = nullptr)
477 : HasError(false)
478#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
479 // Expected is unchecked upon construction in Debug builds.
480 , Unchecked(true)
481#endif
482 {
483 new (getStorage()) storage_type(std::forward<OtherT>(Val));
484 }
485
486 /// Move construct an Expected<T> value.
487 Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
488
489 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
490 /// must be convertible to T.
491 template <class OtherT>
492 Expected(Expected<OtherT> &&Other,
493 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
494 * = nullptr) {
495 moveConstruct(std::move(Other));
496 }
497
498 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
499 /// isn't convertible to T.
500 template <class OtherT>
501 explicit Expected(
502 Expected<OtherT> &&Other,
503 typename std::enable_if<!std::is_convertible<OtherT, T>::value>::type * =
504 nullptr) {
505 moveConstruct(std::move(Other));
506 }
507
508 /// Move-assign from another Expected<T>.
509 Expected &operator=(Expected &&Other) {
510 moveAssign(std::move(Other));
511 return *this;
512 }
513
514 /// Destroy an Expected<T>.
515 ~Expected() {
516 assertIsChecked();
517 if (!HasError)
518 getStorage()->~storage_type();
519 else
520 getErrorStorage()->~error_type();
521 }
522
523 /// Return false if there is an error.
524 explicit operator bool() {
525#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
526 Unchecked = HasError;
527#endif
528 return !HasError;
529 }
530
531 /// Returns a reference to the stored T value.
532 reference get() {
533 assertIsChecked();
534 return *getStorage();
535 }
536
537 /// Returns a const reference to the stored T value.
538 const_reference get() const {
539 assertIsChecked();
540 return const_cast<Expected<T> *>(this)->get();
541 }
542
543 /// Check that this Expected<T> is an error of type ErrT.
544 template <typename ErrT> bool errorIsA() const {
545 return HasError && (*getErrorStorage())->template isA<ErrT>();
546 }
547
548 /// Take ownership of the stored error.
549 /// After calling this the Expected<T> is in an indeterminate state that can
550 /// only be safely destructed. No further calls (beside the destructor) should
551 /// be made on the Expected<T> vaule.
552 Error takeError() {
553#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
554 Unchecked = false;
555#endif
556 return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
557 }
558
559 /// Returns a pointer to the stored T value.
560 pointer operator->() {
561 assertIsChecked();
562 return toPointer(getStorage());
563 }
564
565 /// Returns a const pointer to the stored T value.
566 const_pointer operator->() const {
567 assertIsChecked();
568 return toPointer(getStorage());
569 }
570
571 /// Returns a reference to the stored T value.
572 reference operator*() {
573 assertIsChecked();
574 return *getStorage();
575 }
576
577 /// Returns a const reference to the stored T value.
578 const_reference operator*() const {
579 assertIsChecked();
580 return *getStorage();
581 }
582
583private:
584 template <class T1>
585 static bool compareThisIfSameType(const T1 &a, const T1 &b) {
586 return &a == &b;
587 }
588
589 template <class T1, class T2>
590 static bool compareThisIfSameType(const T1 &a, const T2 &b) {
591 return false;
592 }
593
594 template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) {
595 HasError = Other.HasError;
596#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
597 Unchecked = true;
598 Other.Unchecked = false;
599#endif
600
601 if (!HasError)
602 new (getStorage()) storage_type(std::move(*Other.getStorage()));
603 else
604 new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage()));
605 }
606
607 template <class OtherT> void moveAssign(Expected<OtherT> &&Other) {
608 assertIsChecked();
609
610 if (compareThisIfSameType(*this, Other))
611 return;
612
613 this->~Expected();
614 new (this) Expected(std::move(Other));
615 }
616
617 pointer toPointer(pointer Val) { return Val; }
618
619 const_pointer toPointer(const_pointer Val) const { return Val; }
620
621 pointer toPointer(wrap *Val) { return &Val->get(); }
622
623 const_pointer toPointer(const wrap *Val) const { return &Val->get(); }
624
625 storage_type *getStorage() {
626 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-9~svn362543/include/llvm/Support/Error.h"
, 626, __PRETTY_FUNCTION__))
;
627 return reinterpret_cast<storage_type *>(TStorage.buffer);
628 }
629
630 const storage_type *getStorage() const {
631 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-9~svn362543/include/llvm/Support/Error.h"
, 631, __PRETTY_FUNCTION__))
;
632 return reinterpret_cast<const storage_type *>(TStorage.buffer);
633 }
634
635 error_type *getErrorStorage() {
636 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-9~svn362543/include/llvm/Support/Error.h"
, 636, __PRETTY_FUNCTION__))
;
637 return reinterpret_cast<error_type *>(ErrorStorage.buffer);
638 }
639
640 const error_type *getErrorStorage() const {
641 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-9~svn362543/include/llvm/Support/Error.h"
, 641, __PRETTY_FUNCTION__))
;
642 return reinterpret_cast<const error_type *>(ErrorStorage.buffer);
643 }
644
645 // Used by ExpectedAsOutParameter to reset the checked flag.
646 void setUnchecked() {
647#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
648 Unchecked = true;
649#endif
650 }
651
652#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
653 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
654 LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline))
655 void fatalUncheckedExpected() const {
656 dbgs() << "Expected<T> must be checked before access or destruction.\n";
657 if (HasError) {
658 dbgs() << "Unchecked Expected<T> contained error:\n";
659 (*getErrorStorage())->log(dbgs());
660 } else
661 dbgs() << "Expected<T> value was in success state. (Note: Expected<T> "
662 "values in success mode must still be checked prior to being "
663 "destroyed).\n";
664 abort();
665 }
666#endif
667
668 void assertIsChecked() {
669#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
670 if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false))
671 fatalUncheckedExpected();
672#endif
673 }
674
675 union {
676 AlignedCharArrayUnion<storage_type> TStorage;
677 AlignedCharArrayUnion<error_type> ErrorStorage;
678 };
679 bool HasError : 1;
680#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
681 bool Unchecked : 1;
682#endif
683};
684
685/// Report a serious error, calling any installed error handler. See
686/// ErrorHandling.h.
687LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) void report_fatal_error(Error Err,
688 bool gen_crash_diag = true);
689
690/// Report a fatal error if Err is a failure value.
691///
692/// This function can be used to wrap calls to fallible functions ONLY when it
693/// is known that the Error will always be a success value. E.g.
694///
695/// @code{.cpp}
696/// // foo only attempts the fallible operation if DoFallibleOperation is
697/// // true. If DoFallibleOperation is false then foo always returns
698/// // Error::success().
699/// Error foo(bool DoFallibleOperation);
700///
701/// cantFail(foo(false));
702/// @endcode
703inline void cantFail(Error Err, const char *Msg = nullptr) {
704 if (Err) {
705 if (!Msg)
706 Msg = "Failure value returned from cantFail wrapped call";
707 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 707)
;
708 }
709}
710
711/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
712/// returns the contained value.
713///
714/// This function can be used to wrap calls to fallible functions ONLY when it
715/// is known that the Error will always be a success value. E.g.
716///
717/// @code{.cpp}
718/// // foo only attempts the fallible operation if DoFallibleOperation is
719/// // true. If DoFallibleOperation is false then foo always returns an int.
720/// Expected<int> foo(bool DoFallibleOperation);
721///
722/// int X = cantFail(foo(false));
723/// @endcode
724template <typename T>
725T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) {
726 if (ValOrErr)
727 return std::move(*ValOrErr);
728 else {
729 if (!Msg)
730 Msg = "Failure value returned from cantFail wrapped call";
731 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 731)
;
732 }
733}
734
735/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
736/// returns the contained reference.
737///
738/// This function can be used to wrap calls to fallible functions ONLY when it
739/// is known that the Error will always be a success value. E.g.
740///
741/// @code{.cpp}
742/// // foo only attempts the fallible operation if DoFallibleOperation is
743/// // true. If DoFallibleOperation is false then foo always returns a Bar&.
744/// Expected<Bar&> foo(bool DoFallibleOperation);
745///
746/// Bar &X = cantFail(foo(false));
747/// @endcode
748template <typename T>
749T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) {
750 if (ValOrErr)
751 return *ValOrErr;
752 else {
753 if (!Msg)
754 Msg = "Failure value returned from cantFail wrapped call";
755 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 755)
;
756 }
757}
758
759/// Helper for testing applicability of, and applying, handlers for
760/// ErrorInfo types.
761template <typename HandlerT>
762class ErrorHandlerTraits
763 : public ErrorHandlerTraits<decltype(
764 &std::remove_reference<HandlerT>::type::operator())> {};
765
766// Specialization functions of the form 'Error (const ErrT&)'.
767template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> {
768public:
769 static bool appliesTo(const ErrorInfoBase &E) {
770 return E.template isA<ErrT>();
771 }
772
773 template <typename HandlerT>
774 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
775 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-9~svn362543/include/llvm/Support/Error.h"
, 775, __PRETTY_FUNCTION__))
;
776 return H(static_cast<ErrT &>(*E));
777 }
778};
779
780// Specialization functions of the form 'void (const ErrT&)'.
781template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> {
782public:
783 static bool appliesTo(const ErrorInfoBase &E) {
784 return E.template isA<ErrT>();
785 }
786
787 template <typename HandlerT>
788 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
789 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-9~svn362543/include/llvm/Support/Error.h"
, 789, __PRETTY_FUNCTION__))
;
790 H(static_cast<ErrT &>(*E));
791 return Error::success();
792 }
793};
794
795/// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'.
796template <typename ErrT>
797class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> {
798public:
799 static bool appliesTo(const ErrorInfoBase &E) {
800 return E.template isA<ErrT>();
801 }
802
803 template <typename HandlerT>
804 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
805 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-9~svn362543/include/llvm/Support/Error.h"
, 805, __PRETTY_FUNCTION__))
;
806 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
807 return H(std::move(SubE));
808 }
809};
810
811/// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'.
812template <typename ErrT>
813class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> {
814public:
815 static bool appliesTo(const ErrorInfoBase &E) {
816 return E.template isA<ErrT>();
817 }
818
819 template <typename HandlerT>
820 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
821 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-9~svn362543/include/llvm/Support/Error.h"
, 821, __PRETTY_FUNCTION__))
;
822 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
823 H(std::move(SubE));
824 return Error::success();
825 }
826};
827
828// Specialization for member functions of the form 'RetT (const ErrT&)'.
829template <typename C, typename RetT, typename ErrT>
830class ErrorHandlerTraits<RetT (C::*)(ErrT &)>
831 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
832
833// Specialization for member functions of the form 'RetT (const ErrT&) const'.
834template <typename C, typename RetT, typename ErrT>
835class ErrorHandlerTraits<RetT (C::*)(ErrT &) const>
836 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
837
838// Specialization for member functions of the form 'RetT (const ErrT&)'.
839template <typename C, typename RetT, typename ErrT>
840class ErrorHandlerTraits<RetT (C::*)(const ErrT &)>
841 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
842
843// Specialization for member functions of the form 'RetT (const ErrT&) const'.
844template <typename C, typename RetT, typename ErrT>
845class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const>
846 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
847
848/// Specialization for member functions of the form
849/// 'RetT (std::unique_ptr<ErrT>)'.
850template <typename C, typename RetT, typename ErrT>
851class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)>
852 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
853
854/// Specialization for member functions of the form
855/// 'RetT (std::unique_ptr<ErrT>) const'.
856template <typename C, typename RetT, typename ErrT>
857class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const>
858 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
859
860inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) {
861 return Error(std::move(Payload));
862}
863
864template <typename HandlerT, typename... HandlerTs>
865Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload,
866 HandlerT &&Handler, HandlerTs &&... Handlers) {
867 if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload))
868 return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler),
869 std::move(Payload));
870 return handleErrorImpl(std::move(Payload),
871 std::forward<HandlerTs>(Handlers)...);
872}
873
874/// Pass the ErrorInfo(s) contained in E to their respective handlers. Any
875/// unhandled errors (or Errors returned by handlers) are re-concatenated and
876/// returned.
877/// Because this function returns an error, its result must also be checked
878/// or returned. If you intend to handle all errors use handleAllErrors
879/// (which returns void, and will abort() on unhandled errors) instead.
880template <typename... HandlerTs>
881Error handleErrors(Error E, HandlerTs &&... Hs) {
882 if (!E)
883 return Error::success();
884
885 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
886
887 if (Payload->isA<ErrorList>()) {
888 ErrorList &List = static_cast<ErrorList &>(*Payload);
889 Error R;
890 for (auto &P : List.Payloads)
891 R = ErrorList::join(
892 std::move(R),
893 handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...));
894 return R;
895 }
896
897 return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...);
898}
899
900/// Behaves the same as handleErrors, except that by contract all errors
901/// *must* be handled by the given handlers (i.e. there must be no remaining
902/// errors after running the handlers, or llvm_unreachable is called).
903template <typename... HandlerTs>
904void handleAllErrors(Error E, HandlerTs &&... Handlers) {
905 cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
906}
907
908/// Check that E is a non-error, then drop it.
909/// If E is an error, llvm_unreachable will be called.
910inline void handleAllErrors(Error E) {
911 cantFail(std::move(E));
912}
913
914/// Handle any errors (if present) in an Expected<T>, then try a recovery path.
915///
916/// If the incoming value is a success value it is returned unmodified. If it
917/// is a failure value then it the contained error is passed to handleErrors.
918/// If handleErrors is able to handle the error then the RecoveryPath functor
919/// is called to supply the final result. If handleErrors is not able to
920/// handle all errors then the unhandled errors are returned.
921///
922/// This utility enables the follow pattern:
923///
924/// @code{.cpp}
925/// enum FooStrategy { Aggressive, Conservative };
926/// Expected<Foo> foo(FooStrategy S);
927///
928/// auto ResultOrErr =
929/// handleExpected(
930/// foo(Aggressive),
931/// []() { return foo(Conservative); },
932/// [](AggressiveStrategyError&) {
933/// // Implicitly conusme this - we'll recover by using a conservative
934/// // strategy.
935/// });
936///
937/// @endcode
938template <typename T, typename RecoveryFtor, typename... HandlerTs>
939Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath,
940 HandlerTs &&... Handlers) {
941 if (ValOrErr)
942 return ValOrErr;
943
944 if (auto Err = handleErrors(ValOrErr.takeError(),
945 std::forward<HandlerTs>(Handlers)...))
946 return std::move(Err);
947
948 return RecoveryPath();
949}
950
951/// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner
952/// will be printed before the first one is logged. A newline will be printed
953/// after each error.
954///
955/// This function is compatible with the helpers from Support/WithColor.h. You
956/// can pass any of them as the OS. Please consider using them instead of
957/// including 'error: ' in the ErrorBanner.
958///
959/// This is useful in the base level of your program to allow clean termination
960/// (allowing clean deallocation of resources, etc.), while reporting error
961/// information to the user.
962void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner = {});
963
964/// Write all error messages (if any) in E to a string. The newline character
965/// is used to separate error messages.
966inline std::string toString(Error E) {
967 SmallVector<std::string, 2> Errors;
968 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
969 Errors.push_back(EI.message());
970 });
971 return join(Errors.begin(), Errors.end(), "\n");
972}
973
974/// Consume a Error without doing anything. This method should be used
975/// only where an error can be considered a reasonable and expected return
976/// value.
977///
978/// Uses of this method are potentially indicative of design problems: If it's
979/// legitimate to do nothing while processing an "error", the error-producer
980/// might be more clearly refactored to return an Optional<T>.
981inline void consumeError(Error Err) {
982 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
983}
984
985/// Helper for converting an Error to a bool.
986///
987/// This method returns true if Err is in an error state, or false if it is
988/// in a success state. Puts Err in a checked state in both cases (unlike
989/// Error::operator bool(), which only does this for success states).
990inline bool errorToBool(Error Err) {
991 bool IsError = static_cast<bool>(Err);
992 if (IsError)
993 consumeError(std::move(Err));
994 return IsError;
995}
996
997/// Helper for Errors used as out-parameters.
998///
999/// This helper is for use with the Error-as-out-parameter idiom, where an error
1000/// is passed to a function or method by reference, rather than being returned.
1001/// In such cases it is helpful to set the checked bit on entry to the function
1002/// so that the error can be written to (unchecked Errors abort on assignment)
1003/// and clear the checked bit on exit so that clients cannot accidentally forget
1004/// to check the result. This helper performs these actions automatically using
1005/// RAII:
1006///
1007/// @code{.cpp}
1008/// Result foo(Error &Err) {
1009/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1010/// // <body of foo>
1011/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1012/// }
1013/// @endcode
1014///
1015/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1016/// used with optional Errors (Error pointers that are allowed to be null). If
1017/// ErrorAsOutParameter took an Error reference, an instance would have to be
1018/// created inside every condition that verified that Error was non-null. By
1019/// taking an Error pointer we can just create one instance at the top of the
1020/// function.
1021class ErrorAsOutParameter {
1022public:
1023 ErrorAsOutParameter(Error *Err) : Err(Err) {
1024 // Raise the checked bit if Err is success.
1025 if (Err)
1026 (void)!!*Err;
1027 }
1028
1029 ~ErrorAsOutParameter() {
1030 // Clear the checked bit.
1031 if (Err && !*Err)
1032 *Err = Error::success();
1033 }
1034
1035private:
1036 Error *Err;
1037};
1038
1039/// Helper for Expected<T>s used as out-parameters.
1040///
1041/// See ErrorAsOutParameter.
1042template <typename T>
1043class ExpectedAsOutParameter {
1044public:
1045 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1046 : ValOrErr(ValOrErr) {
1047 if (ValOrErr)
1048 (void)!!*ValOrErr;
1049 }
1050
1051 ~ExpectedAsOutParameter() {
1052 if (ValOrErr)
1053 ValOrErr->setUnchecked();
1054 }
1055
1056private:
1057 Expected<T> *ValOrErr;
1058};
1059
1060/// This class wraps a std::error_code in a Error.
1061///
1062/// This is useful if you're writing an interface that returns a Error
1063/// (or Expected) and you want to call code that still returns
1064/// std::error_codes.
1065class ECError : public ErrorInfo<ECError> {
1066 friend Error errorCodeToError(std::error_code);
1067
1068 virtual void anchor() override;
1069
1070public:
1071 void setErrorCode(std::error_code EC) { this->EC = EC; }
1072 std::error_code convertToErrorCode() const override { return EC; }
1073 void log(raw_ostream &OS) const override { OS << EC.message(); }
1074
1075 // Used by ErrorInfo::classID.
1076 static char ID;
1077
1078protected:
1079 ECError() = default;
1080 ECError(std::error_code EC) : EC(EC) {}
1081
1082 std::error_code EC;
1083};
1084
1085/// The value returned by this function can be returned from convertToErrorCode
1086/// for Error values where no sensible translation to std::error_code exists.
1087/// It should only be used in this situation, and should never be used where a
1088/// sensible conversion to std::error_code is available, as attempts to convert
1089/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1090///error to try to convert such a value).
1091std::error_code inconvertibleErrorCode();
1092
1093/// Helper for converting an std::error_code to a Error.
1094Error errorCodeToError(std::error_code EC);
1095
1096/// Helper for converting an ECError to a std::error_code.
1097///
1098/// This method requires that Err be Error() or an ECError, otherwise it
1099/// will trigger a call to abort().
1100std::error_code errorToErrorCode(Error Err);
1101
1102/// Convert an ErrorOr<T> to an Expected<T>.
1103template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1104 if (auto EC = EO.getError())
1105 return errorCodeToError(EC);
1106 return std::move(*EO);
1107}
1108
1109/// Convert an Expected<T> to an ErrorOr<T>.
1110template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1111 if (auto Err = E.takeError())
1112 return errorToErrorCode(std::move(Err));
1113 return std::move(*E);
1114}
1115
1116/// This class wraps a string in an Error.
1117///
1118/// StringError is useful in cases where the client is not expected to be able
1119/// to consume the specific error message programmatically (for example, if the
1120/// error message is to be presented to the user).
1121///
1122/// StringError can also be used when additional information is to be printed
1123/// along with a error_code message. Depending on the constructor called, this
1124/// class can either display:
1125/// 1. the error_code message (ECError behavior)
1126/// 2. a string
1127/// 3. the error_code message and a string
1128///
1129/// These behaviors are useful when subtyping is required; for example, when a
1130/// specific library needs an explicit error type. In the example below,
1131/// PDBError is derived from StringError:
1132///
1133/// @code{.cpp}
1134/// Expected<int> foo() {
1135/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1136/// "Additional information");
1137/// }
1138/// @endcode
1139///
1140class StringError : public ErrorInfo<StringError> {
1141public:
1142 static char ID;
1143
1144 // Prints EC + S and converts to EC
1145 StringError(std::error_code EC, const Twine &S = Twine());
1146
1147 // Prints S and converts to EC
1148 StringError(const Twine &S, std::error_code EC);
1149
1150 void log(raw_ostream &OS) const override;
1151 std::error_code convertToErrorCode() const override;
1152
1153 const std::string &getMessage() const { return Msg; }
1154
1155private:
1156 std::string Msg;
1157 std::error_code EC;
1158 const bool PrintMsgOnly = false;
1159};
1160
1161/// Create formatted StringError object.
1162template <typename... Ts>
1163Error createStringError(std::error_code EC, char const *Fmt,
1164 const Ts &... Vals) {
1165 std::string Buffer;
1166 raw_string_ostream Stream(Buffer);
1167 Stream << format(Fmt, Vals...);
1168 return make_error<StringError>(Stream.str(), EC);
1169}
1170
1171Error createStringError(std::error_code EC, char const *Msg);
1172
1173/// This class wraps a filename and another Error.
1174///
1175/// In some cases, an error needs to live along a 'source' name, in order to
1176/// show more detailed information to the user.
1177class FileError final : public ErrorInfo<FileError> {
1178
1179 friend Error createFileError(const Twine &, Error);
1180 friend Error createFileError(const Twine &, size_t, Error);
1181
1182public:
1183 void log(raw_ostream &OS) const override {
1184 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-9~svn362543/include/llvm/Support/Error.h"
, 1184, __PRETTY_FUNCTION__))
;
1185 OS << "'" << FileName << "': ";
1186 if (Line.hasValue())
1187 OS << "line " << Line.getValue() << ": ";
1188 Err->log(OS);
1189 }
1190
1191 Error takeError() { return Error(std::move(Err)); }
1192
1193 std::error_code convertToErrorCode() const override;
1194
1195 // Used by ErrorInfo::classID.
1196 static char ID;
1197
1198private:
1199 FileError(const Twine &F, Optional<size_t> LineNum,
1200 std::unique_ptr<ErrorInfoBase> E) {
1201 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-9~svn362543/include/llvm/Support/Error.h"
, 1201, __PRETTY_FUNCTION__))
;
1202 assert(!F.isTriviallyEmpty() &&((!F.isTriviallyEmpty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.isTriviallyEmpty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 1203, __PRETTY_FUNCTION__))
1203 "The file name provided to FileError must not be empty.")((!F.isTriviallyEmpty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.isTriviallyEmpty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/Support/Error.h"
, 1203, __PRETTY_FUNCTION__))
;
1204 FileName = F.str();
1205 Err = std::move(E);
1206 Line = std::move(LineNum);
1207 }
1208
1209 static Error build(const Twine &F, Optional<size_t> Line, Error E) {
1210 return Error(
1211 std::unique_ptr<FileError>(new FileError(F, Line, E.takePayload())));
1212 }
1213
1214 std::string FileName;
1215 Optional<size_t> Line;
1216 std::unique_ptr<ErrorInfoBase> Err;
1217};
1218
1219/// Concatenate a source file path and/or name with an Error. The resulting
1220/// Error is unchecked.
1221inline Error createFileError(const Twine &F, Error E) {
1222 return FileError::build(F, Optional<size_t>(), std::move(E));
1223}
1224
1225/// Concatenate a source file path and/or name with line number and an Error.
1226/// The resulting Error is unchecked.
1227inline Error createFileError(const Twine &F, size_t Line, Error E) {
1228 return FileError::build(F, Optional<size_t>(Line), std::move(E));
1229}
1230
1231/// Concatenate a source file path and/or name with a std::error_code
1232/// to form an Error object.
1233inline Error createFileError(const Twine &F, std::error_code EC) {
1234 return createFileError(F, errorCodeToError(EC));
1235}
1236
1237/// Concatenate a source file path and/or name with line number and
1238/// std::error_code to form an Error object.
1239inline Error createFileError(const Twine &F, size_t Line, std::error_code EC) {
1240 return createFileError(F, Line, errorCodeToError(EC));
1241}
1242
1243Error createFileError(const Twine &F, ErrorSuccess) = delete;
1244
1245/// Helper for check-and-exit error handling.
1246///
1247/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1248///
1249class ExitOnError {
1250public:
1251 /// Create an error on exit helper.
1252 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1253 : Banner(std::move(Banner)),
1254 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1255
1256 /// Set the banner string for any errors caught by operator().
1257 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1258
1259 /// Set the exit-code mapper function.
1260 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1261 this->GetExitCode = std::move(GetExitCode);
1262 }
1263
1264 /// Check Err. If it's in a failure state log the error(s) and exit.
1265 void operator()(Error Err) const { checkError(std::move(Err)); }
1266
1267 /// Check E. If it's in a success state then return the contained value. If
1268 /// it's in a failure state log the error(s) and exit.
1269 template <typename T> T operator()(Expected<T> &&E) const {
1270 checkError(E.takeError());
1271 return std::move(*E);
1272 }
1273
1274 /// Check E. If it's in a success state then return the contained reference. If
1275 /// it's in a failure state log the error(s) and exit.
1276 template <typename T> T& operator()(Expected<T&> &&E) const {
1277 checkError(E.takeError());
1278 return *E;
1279 }
1280
1281private:
1282 void checkError(Error Err) const {
1283 if (Err) {
1284 int ExitCode = GetExitCode(Err);
1285 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1286 exit(ExitCode);
1287 }
1288 }
1289
1290 std::string Banner;
1291 std::function<int(const Error &)> GetExitCode;
1292};
1293
1294/// Conversion from Error to LLVMErrorRef for C error bindings.
1295inline LLVMErrorRef wrap(Error Err) {
1296 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1297}
1298
1299/// Conversion from LLVMErrorRef to Error for C error bindings.
1300inline Error unwrap(LLVMErrorRef ErrRef) {
1301 return Error(std::unique_ptr<ErrorInfoBase>(
1302 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1303}
1304
1305} // end namespace llvm
1306
1307#endif // LLVM_SUPPORT_ERROR_H

/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/STLExtras.h

1//===- llvm/ADT/STLExtras.h - Useful STL related functions ------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file contains some templates that are useful if you are working with the
10// STL at all.
11//
12// No library is required when using these functions.
13//
14//===----------------------------------------------------------------------===//
15
16#ifndef LLVM_ADT_STLEXTRAS_H
17#define LLVM_ADT_STLEXTRAS_H
18
19#include "llvm/ADT/Optional.h"
20#include "llvm/ADT/SmallVector.h"
21#include "llvm/ADT/iterator.h"
22#include "llvm/ADT/iterator_range.h"
23#include "llvm/Config/abi-breaking.h"
24#include "llvm/Support/ErrorHandling.h"
25#include <algorithm>
26#include <cassert>
27#include <cstddef>
28#include <cstdint>
29#include <cstdlib>
30#include <functional>
31#include <initializer_list>
32#include <iterator>
33#include <limits>
34#include <memory>
35#include <tuple>
36#include <type_traits>
37#include <utility>
38
39#ifdef EXPENSIVE_CHECKS
40#include <random> // for std::mt19937
41#endif
42
43namespace llvm {
44
45// Only used by compiler if both template types are the same. Useful when
46// using SFINAE to test for the existence of member functions.
47template <typename T, T> struct SameType;
48
49namespace detail {
50
51template <typename RangeT>
52using IterOfRange = decltype(std::begin(std::declval<RangeT &>()));
53
54template <typename RangeT>
55using ValueOfRange = typename std::remove_reference<decltype(
56 *std::begin(std::declval<RangeT &>()))>::type;
57
58} // end namespace detail
59
60//===----------------------------------------------------------------------===//
61// Extra additions to <type_traits>
62//===----------------------------------------------------------------------===//
63
64template <typename T>
65struct negation : std::integral_constant<bool, !bool(T::value)> {};
66
67template <typename...> struct conjunction : std::true_type {};
68template <typename B1> struct conjunction<B1> : B1 {};
69template <typename B1, typename... Bn>
70struct conjunction<B1, Bn...>
71 : std::conditional<bool(B1::value), conjunction<Bn...>, B1>::type {};
72
73template <typename T> struct make_const_ptr {
74 using type =
75 typename std::add_pointer<typename std::add_const<T>::type>::type;
76};
77
78template <typename T> struct make_const_ref {
79 using type = typename std::add_lvalue_reference<
80 typename std::add_const<T>::type>::type;
81};
82
83//===----------------------------------------------------------------------===//
84// Extra additions to <functional>
85//===----------------------------------------------------------------------===//
86
87template <class Ty> struct identity {
88 using argument_type = Ty;
89
90 Ty &operator()(Ty &self) const {
91 return self;
92 }
93 const Ty &operator()(const Ty &self) const {
94 return self;
95 }
96};
97
98template <class Ty> struct less_ptr {
99 bool operator()(const Ty* left, const Ty* right) const {
100 return *left < *right;
101 }
102};
103
104template <class Ty> struct greater_ptr {
105 bool operator()(const Ty* left, const Ty* right) const {
106 return *right < *left;
107 }
108};
109
110/// An efficient, type-erasing, non-owning reference to a callable. This is
111/// intended for use as the type of a function parameter that is not used
112/// after the function in question returns.
113///
114/// This class does not own the callable, so it is not in general safe to store
115/// a function_ref.
116template<typename Fn> class function_ref;
117
118template<typename Ret, typename ...Params>
119class function_ref<Ret(Params...)> {
120 Ret (*callback)(intptr_t callable, Params ...params) = nullptr;
121 intptr_t callable;
122
123 template<typename Callable>
124 static Ret callback_fn(intptr_t callable, Params ...params) {
125 return (*reinterpret_cast<Callable*>(callable))(
126 std::forward<Params>(params)...);
127 }
128
129public:
130 function_ref() = default;
131 function_ref(std::nullptr_t) {}
132
133 template <typename Callable>
134 function_ref(Callable &&callable,
135 typename std::enable_if<
136 !std::is_same<typename std::remove_reference<Callable>::type,
137 function_ref>::value>::type * = nullptr)
138 : callback(callback_fn<typename std::remove_reference<Callable>::type>),
139 callable(reinterpret_cast<intptr_t>(&callable)) {}
140
141 Ret operator()(Params ...params) const {
142 return callback(callable, std::forward<Params>(params)...);
143 }
144
145 operator bool() const { return callback; }
146};
147
148// deleter - Very very very simple method that is used to invoke operator
149// delete on something. It is used like this:
150//
151// for_each(V.begin(), B.end(), deleter<Interval>);
152template <class T>
153inline void deleter(T *Ptr) {
154 delete Ptr;
155}
156
157//===----------------------------------------------------------------------===//
158// Extra additions to <iterator>
159//===----------------------------------------------------------------------===//
160
161namespace adl_detail {
162
163using std::begin;
164
165template <typename ContainerTy>
166auto adl_begin(ContainerTy &&container)
167 -> decltype(begin(std::forward<ContainerTy>(container))) {
168 return begin(std::forward<ContainerTy>(container));
169}
170
171using std::end;
172
173template <typename ContainerTy>
174auto adl_end(ContainerTy &&container)
175 -> decltype(end(std::forward<ContainerTy>(container))) {
176 return end(std::forward<ContainerTy>(container));
177}
178
179using std::swap;
180
181template <typename T>
182void adl_swap(T &&lhs, T &&rhs) noexcept(noexcept(swap(std::declval<T>(),
183 std::declval<T>()))) {
184 swap(std::forward<T>(lhs), std::forward<T>(rhs));
185}
186
187} // end namespace adl_detail
188
189template <typename ContainerTy>
190auto adl_begin(ContainerTy &&container)
191 -> decltype(adl_detail::adl_begin(std::forward<ContainerTy>(container))) {
192 return adl_detail::adl_begin(std::forward<ContainerTy>(container));
193}
194
195template <typename ContainerTy>
196auto adl_end(ContainerTy &&container)
197 -> decltype(adl_detail::adl_end(std::forward<ContainerTy>(container))) {
198 return adl_detail::adl_end(std::forward<ContainerTy>(container));
199}
200
201template <typename T>
202void adl_swap(T &&lhs, T &&rhs) noexcept(
203 noexcept(adl_detail::adl_swap(std::declval<T>(), std::declval<T>()))) {
204 adl_detail::adl_swap(std::forward<T>(lhs), std::forward<T>(rhs));
205}
206
207/// Test whether \p RangeOrContainer is empty. Similar to C++17 std::empty.
208template <typename T>
209constexpr bool empty(const T &RangeOrContainer) {
210 return adl_begin(RangeOrContainer) == adl_end(RangeOrContainer);
211}
212
213// mapped_iterator - This is a simple iterator adapter that causes a function to
214// be applied whenever operator* is invoked on the iterator.
215
216template <typename ItTy, typename FuncTy,
217 typename FuncReturnTy =
218 decltype(std::declval<FuncTy>()(*std::declval<ItTy>()))>
219class mapped_iterator
220 : public iterator_adaptor_base<
221 mapped_iterator<ItTy, FuncTy>, ItTy,
222 typename std::iterator_traits<ItTy>::iterator_category,
223 typename std::remove_reference<FuncReturnTy>::type> {
224public:
225 mapped_iterator(ItTy U, FuncTy F)
226 : mapped_iterator::iterator_adaptor_base(std::move(U)), F(std::move(F)) {}
227
228 ItTy getCurrent() { return this->I; }
229
230 FuncReturnTy operator*() { return F(*this->I); }
231
232private:
233 FuncTy F;
234};
235
236// map_iterator - Provide a convenient way to create mapped_iterators, just like
237// make_pair is useful for creating pairs...
238template <class ItTy, class FuncTy>
239inline mapped_iterator<ItTy, FuncTy> map_iterator(ItTy I, FuncTy F) {
240 return mapped_iterator<ItTy, FuncTy>(std::move(I), std::move(F));
241}
242
243/// Helper to determine if type T has a member called rbegin().
244template <typename Ty> class has_rbegin_impl {
245 using yes = char[1];
246 using no = char[2];
247
248 template <typename Inner>
249 static yes& test(Inner *I, decltype(I->rbegin()) * = nullptr);
250
251 template <typename>
252 static no& test(...);
253
254public:
255 static const bool value = sizeof(test<Ty>(nullptr)) == sizeof(yes);
256};
257
258/// Metafunction to determine if T& or T has a member called rbegin().
259template <typename Ty>
260struct has_rbegin : has_rbegin_impl<typename std::remove_reference<Ty>::type> {
261};
262
263// Returns an iterator_range over the given container which iterates in reverse.
264// Note that the container must have rbegin()/rend() methods for this to work.
265template <typename ContainerTy>
266auto reverse(ContainerTy &&C,
267 typename std::enable_if<has_rbegin<ContainerTy>::value>::type * =
268 nullptr) -> decltype(make_range(C.rbegin(), C.rend())) {
269 return make_range(C.rbegin(), C.rend());
270}
271
272// Returns a std::reverse_iterator wrapped around the given iterator.
273template <typename IteratorTy>
274std::reverse_iterator<IteratorTy> make_reverse_iterator(IteratorTy It) {
275 return std::reverse_iterator<IteratorTy>(It);
276}
277
278// Returns an iterator_range over the given container which iterates in reverse.
279// Note that the container must have begin()/end() methods which return
280// bidirectional iterators for this to work.
281template <typename ContainerTy>
282auto reverse(
283 ContainerTy &&C,
284 typename std::enable_if<!has_rbegin<ContainerTy>::value>::type * = nullptr)
285 -> decltype(make_range(llvm::make_reverse_iterator(std::end(C)),
286 llvm::make_reverse_iterator(std::begin(C)))) {
287 return make_range(llvm::make_reverse_iterator(std::end(C)),
288 llvm::make_reverse_iterator(std::begin(C)));
289}
290
291/// An iterator adaptor that filters the elements of given inner iterators.
292///
293/// The predicate parameter should be a callable object that accepts the wrapped
294/// iterator's reference type and returns a bool. When incrementing or
295/// decrementing the iterator, it will call the predicate on each element and
296/// skip any where it returns false.
297///
298/// \code
299/// int A[] = { 1, 2, 3, 4 };
300/// auto R = make_filter_range(A, [](int N) { return N % 2 == 1; });
301/// // R contains { 1, 3 }.
302/// \endcode
303///
304/// Note: filter_iterator_base implements support for forward iteration.
305/// filter_iterator_impl exists to provide support for bidirectional iteration,
306/// conditional on whether the wrapped iterator supports it.
307template <typename WrappedIteratorT, typename PredicateT, typename IterTag>
308class filter_iterator_base
309 : public iterator_adaptor_base<
310 filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
311 WrappedIteratorT,
312 typename std::common_type<
313 IterTag, typename std::iterator_traits<
314 WrappedIteratorT>::iterator_category>::type> {
315 using BaseT = iterator_adaptor_base<
316 filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
317 WrappedIteratorT,
318 typename std::common_type<
319 IterTag, typename std::iterator_traits<
320 WrappedIteratorT>::iterator_category>::type>;
321
322protected:
323 WrappedIteratorT End;
324 PredicateT Pred;
325
326 void findNextValid() {
327 while (this->I != End && !Pred(*this->I))
328 BaseT::operator++();
329 }
330
331 // Construct the iterator. The begin iterator needs to know where the end
332 // is, so that it can properly stop when it gets there. The end iterator only
333 // needs the predicate to support bidirectional iteration.
334 filter_iterator_base(WrappedIteratorT Begin, WrappedIteratorT End,
335 PredicateT Pred)
336 : BaseT(Begin), End(End), Pred(Pred) {
337 findNextValid();
338 }
339
340public:
341 using BaseT::operator++;
342
343 filter_iterator_base &operator++() {
344 BaseT::operator++();
345 findNextValid();
346 return *this;
347 }
348};
349
350/// Specialization of filter_iterator_base for forward iteration only.
351template <typename WrappedIteratorT, typename PredicateT,
352 typename IterTag = std::forward_iterator_tag>
353class filter_iterator_impl
354 : public filter_iterator_base<WrappedIteratorT, PredicateT, IterTag> {
355 using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>;
356
357public:
358 filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
359 PredicateT Pred)
360 : BaseT(Begin, End, Pred) {}
361};
362
363/// Specialization of filter_iterator_base for bidirectional iteration.
364template <typename WrappedIteratorT, typename PredicateT>
365class filter_iterator_impl<WrappedIteratorT, PredicateT,
366 std::bidirectional_iterator_tag>
367 : public filter_iterator_base<WrappedIteratorT, PredicateT,
368 std::bidirectional_iterator_tag> {
369 using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT,
370 std::bidirectional_iterator_tag>;
371 void findPrevValid() {
372 while (!this->Pred(*this->I))
373 BaseT::operator--();
374 }
375
376public:
377 using BaseT::operator--;
378
379 filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
380 PredicateT Pred)
381 : BaseT(Begin, End, Pred) {}
382
383 filter_iterator_impl &operator--() {
384 BaseT::operator--();
385 findPrevValid();
386 return *this;
387 }
388};
389
390namespace detail {
391
392template <bool is_bidirectional> struct fwd_or_bidi_tag_impl {
393 using type = std::forward_iterator_tag;
394};
395
396template <> struct fwd_or_bidi_tag_impl<true> {
397 using type = std::bidirectional_iterator_tag;
398};
399
400/// Helper which sets its type member to forward_iterator_tag if the category
401/// of \p IterT does not derive from bidirectional_iterator_tag, and to
402/// bidirectional_iterator_tag otherwise.
403template <typename IterT> struct fwd_or_bidi_tag {
404 using type = typename fwd_or_bidi_tag_impl<std::is_base_of<
405 std::bidirectional_iterator_tag,
406 typename std::iterator_traits<IterT>::iterator_category>::value>::type;
407};
408
409} // namespace detail
410
411/// Defines filter_iterator to a suitable specialization of
412/// filter_iterator_impl, based on the underlying iterator's category.
413template <typename WrappedIteratorT, typename PredicateT>
414using filter_iterator = filter_iterator_impl<
415 WrappedIteratorT, PredicateT,
416 typename detail::fwd_or_bidi_tag<WrappedIteratorT>::type>;
417
418/// Convenience function that takes a range of elements and a predicate,
419/// and return a new filter_iterator range.
420///
421/// FIXME: Currently if RangeT && is a rvalue reference to a temporary, the
422/// lifetime of that temporary is not kept by the returned range object, and the
423/// temporary is going to be dropped on the floor after the make_iterator_range
424/// full expression that contains this function call.
425template <typename RangeT, typename PredicateT>
426iterator_range<filter_iterator<detail::IterOfRange<RangeT>, PredicateT>>
427make_filter_range(RangeT &&Range, PredicateT Pred) {
428 using FilterIteratorT =
429 filter_iterator<detail::IterOfRange<RangeT>, PredicateT>;
430 return make_range(
431 FilterIteratorT(std::begin(std::forward<RangeT>(Range)),
432 std::end(std::forward<RangeT>(Range)), Pred),
433 FilterIteratorT(std::end(std::forward<RangeT>(Range)),
434 std::end(std::forward<RangeT>(Range)), Pred));
435}
436
437/// A pseudo-iterator adaptor that is designed to implement "early increment"
438/// style loops.
439///
440/// This is *not a normal iterator* and should almost never be used directly. It
441/// is intended primarily to be used with range based for loops and some range
442/// algorithms.
443///
444/// The iterator isn't quite an `OutputIterator` or an `InputIterator` but
445/// somewhere between them. The constraints of these iterators are:
446///
447/// - On construction or after being incremented, it is comparable and
448/// dereferencable. It is *not* incrementable.
449/// - After being dereferenced, it is neither comparable nor dereferencable, it
450/// is only incrementable.
451///
452/// This means you can only dereference the iterator once, and you can only
453/// increment it once between dereferences.
454template <typename WrappedIteratorT>
455class early_inc_iterator_impl
456 : public iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
457 WrappedIteratorT, std::input_iterator_tag> {
458 using BaseT =
459 iterator_adaptor_base<early_inc_iterator_impl<WrappedIteratorT>,
460 WrappedIteratorT, std::input_iterator_tag>;
461
462 using PointerT = typename std::iterator_traits<WrappedIteratorT>::pointer;
463
464protected:
465#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
466 bool IsEarlyIncremented = false;
467#endif
468
469public:
470 early_inc_iterator_impl(WrappedIteratorT I) : BaseT(I) {}
471
472 using BaseT::operator*;
473 typename BaseT::reference operator*() {
474#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
475 assert(!IsEarlyIncremented && "Cannot dereference twice!")((!IsEarlyIncremented && "Cannot dereference twice!")
? static_cast<void> (0) : __assert_fail ("!IsEarlyIncremented && \"Cannot dereference twice!\""
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/STLExtras.h"
, 475, __PRETTY_FUNCTION__))
;
476 IsEarlyIncremented = true;
477#endif
478 return *(this->I)++;
479 }
480
481 using BaseT::operator++;
482 early_inc_iterator_impl &operator++() {
483#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
484 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-9~svn362543/include/llvm/ADT/STLExtras.h"
, 484, __PRETTY_FUNCTION__))
;
485 IsEarlyIncremented = false;
486#endif
487 return *this;
488 }
489
490 using BaseT::operator==;
491 bool operator==(const early_inc_iterator_impl &RHS) const {
492#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
493 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-9~svn362543/include/llvm/ADT/STLExtras.h"
, 493, __PRETTY_FUNCTION__))
;
494#endif
495 return BaseT::operator==(RHS);
496 }
497};
498
499/// Make a range that does early increment to allow mutation of the underlying
500/// range without disrupting iteration.
501///
502/// The underlying iterator will be incremented immediately after it is
503/// dereferenced, allowing deletion of the current node or insertion of nodes to
504/// not disrupt iteration provided they do not invalidate the *next* iterator --
505/// the current iterator can be invalidated.
506///
507/// This requires a very exact pattern of use that is only really suitable to
508/// range based for loops and other range algorithms that explicitly guarantee
509/// to dereference exactly once each element, and to increment exactly once each
510/// element.
511template <typename RangeT>
512iterator_range<early_inc_iterator_impl<detail::IterOfRange<RangeT>>>
513make_early_inc_range(RangeT &&Range) {
514 using EarlyIncIteratorT =
515 early_inc_iterator_impl<detail::IterOfRange<RangeT>>;
516 return make_range(EarlyIncIteratorT(std::begin(std::forward<RangeT>(Range))),
517 EarlyIncIteratorT(std::end(std::forward<RangeT>(Range))));
518}
519
520// forward declarations required by zip_shortest/zip_first/zip_longest
521template <typename R, typename UnaryPredicate>
522bool all_of(R &&range, UnaryPredicate P);
523template <typename R, typename UnaryPredicate>
524bool any_of(R &&range, UnaryPredicate P);
525
526template <size_t... I> struct index_sequence;
527
528template <class... Ts> struct index_sequence_for;
529
530namespace detail {
531
532using std::declval;
533
534// We have to alias this since inlining the actual type at the usage site
535// in the parameter list of iterator_facade_base<> below ICEs MSVC 2017.
536template<typename... Iters> struct ZipTupleType {
537 using type = std::tuple<decltype(*declval<Iters>())...>;
538};
539
540template <typename ZipType, typename... Iters>
541using zip_traits = iterator_facade_base<
542 ZipType, typename std::common_type<std::bidirectional_iterator_tag,
543 typename std::iterator_traits<
544 Iters>::iterator_category...>::type,
545 // ^ TODO: Implement random access methods.
546 typename ZipTupleType<Iters...>::type,
547 typename std::iterator_traits<typename std::tuple_element<
548 0, std::tuple<Iters...>>::type>::difference_type,
549 // ^ FIXME: This follows boost::make_zip_iterator's assumption that all
550 // inner iterators have the same difference_type. It would fail if, for
551 // instance, the second field's difference_type were non-numeric while the
552 // first is.
553 typename ZipTupleType<Iters...>::type *,
554 typename ZipTupleType<Iters...>::type>;
555
556template <typename ZipType, typename... Iters>
557struct zip_common : public zip_traits<ZipType, Iters...> {
558 using Base = zip_traits<ZipType, Iters...>;
559 using value_type = typename Base::value_type;
560
561 std::tuple<Iters...> iterators;
562
563protected:
564 template <size_t... Ns> value_type deref(index_sequence<Ns...>) const {
565 return value_type(*std::get<Ns>(iterators)...);
566 }
567
568 template <size_t... Ns>
569 decltype(iterators) tup_inc(index_sequence<Ns...>) const {
570 return std::tuple<Iters...>(std::next(std::get<Ns>(iterators))...);
571 }
572
573 template <size_t... Ns>
574 decltype(iterators) tup_dec(index_sequence<Ns...>) const {
575 return std::tuple<Iters...>(std::prev(std::get<Ns>(iterators))...);
576 }
577
578public:
579 zip_common(Iters &&... ts) : iterators(std::forward<Iters>(ts)...) {}
580
581 value_type operator*() { return deref(index_sequence_for<Iters...>{}); }
582
583 const value_type operator*() const {
584 return deref(index_sequence_for<Iters...>{});
585 }
586
587 ZipType &operator++() {
588 iterators = tup_inc(index_sequence_for<Iters...>{});
589 return *reinterpret_cast<ZipType *>(this);
590 }
591
592 ZipType &operator--() {
593 static_assert(Base::IsBidirectional,
594 "All inner iterators must be at least bidirectional.");
595 iterators = tup_dec(index_sequence_for<Iters...>{});
596 return *reinterpret_cast<ZipType *>(this);
597 }
598};
599
600template <typename... Iters>
601struct zip_first : public zip_common<zip_first<Iters...>, Iters...> {
602 using Base = zip_common<zip_first<Iters...>, Iters...>;
603
604 bool operator==(const zip_first<Iters...> &other) const {
605 return std::get<0>(this->iterators) == std::get<0>(other.iterators);
606 }
607
608 zip_first(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
609};
610
611template <typename... Iters>
612class zip_shortest : public zip_common<zip_shortest<Iters...>, Iters...> {
613 template <size_t... Ns>
614 bool test(const zip_shortest<Iters...> &other, index_sequence<Ns...>) const {
615 return all_of(std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
616 std::get<Ns>(other.iterators)...},
617 identity<bool>{});
618 }
619
620public:
621 using Base = zip_common<zip_shortest<Iters...>, Iters...>;
622
623 zip_shortest(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
624
625 bool operator==(const zip_shortest<Iters...> &other) const {
626 return !test(other, index_sequence_for<Iters...>{});
627 }
628};
629
630template <template <typename...> class ItType, typename... Args> class zippy {
631public:
632 using iterator = ItType<decltype(std::begin(std::declval<Args>()))...>;
633 using iterator_category = typename iterator::iterator_category;
634 using value_type = typename iterator::value_type;
635 using difference_type = typename iterator::difference_type;
636 using pointer = typename iterator::pointer;
637 using reference = typename iterator::reference;
638
639private:
640 std::tuple<Args...> ts;
641
642 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) const {
643 return iterator(std::begin(std::get<Ns>(ts))...);
644 }
645 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) const {
646 return iterator(std::end(std::get<Ns>(ts))...);
647 }
648
649public:
650 zippy(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
651
652 iterator begin() const { return begin_impl(index_sequence_for<Args...>{}); }
653 iterator end() const { return end_impl(index_sequence_for<Args...>{}); }
654};
655
656} // end namespace detail
657
658/// zip iterator for two or more iteratable types.
659template <typename T, typename U, typename... Args>
660detail::zippy<detail::zip_shortest, T, U, Args...> zip(T &&t, U &&u,
661 Args &&... args) {
662 return detail::zippy<detail::zip_shortest, T, U, Args...>(
663 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
664}
665
666/// zip iterator that, for the sake of efficiency, assumes the first iteratee to
667/// be the shortest.
668template <typename T, typename U, typename... Args>
669detail::zippy<detail::zip_first, T, U, Args...> zip_first(T &&t, U &&u,
670 Args &&... args) {
671 return detail::zippy<detail::zip_first, T, U, Args...>(
672 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
673}
674
675namespace detail {
676template <typename Iter>
677static Iter next_or_end(const Iter &I, const Iter &End) {
678 if (I == End)
679 return End;
680 return std::next(I);
681}
682
683template <typename Iter>
684static auto deref_or_none(const Iter &I, const Iter &End)
685 -> llvm::Optional<typename std::remove_const<
686 typename std::remove_reference<decltype(*I)>::type>::type> {
687 if (I == End)
688 return None;
689 return *I;
690}
691
692template <typename Iter> struct ZipLongestItemType {
693 using type =
694 llvm::Optional<typename std::remove_const<typename std::remove_reference<
695 decltype(*std::declval<Iter>())>::type>::type>;
696};
697
698template <typename... Iters> struct ZipLongestTupleType {
699 using type = std::tuple<typename ZipLongestItemType<Iters>::type...>;
700};
701
702template <typename... Iters>
703class zip_longest_iterator
704 : public iterator_facade_base<
705 zip_longest_iterator<Iters...>,
706 typename std::common_type<
707 std::forward_iterator_tag,
708 typename std::iterator_traits<Iters>::iterator_category...>::type,
709 typename ZipLongestTupleType<Iters...>::type,
710 typename std::iterator_traits<typename std::tuple_element<
711 0, std::tuple<Iters...>>::type>::difference_type,
712 typename ZipLongestTupleType<Iters...>::type *,
713 typename ZipLongestTupleType<Iters...>::type> {
714public:
715 using value_type = typename ZipLongestTupleType<Iters...>::type;
716
717private:
718 std::tuple<Iters...> iterators;
719 std::tuple<Iters...> end_iterators;
720
721 template <size_t... Ns>
722 bool test(const zip_longest_iterator<Iters...> &other,
723 index_sequence<Ns...>) const {
724 return llvm::any_of(
725 std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
726 std::get<Ns>(other.iterators)...},
727 identity<bool>{});
728 }
729
730 template <size_t... Ns> value_type deref(index_sequence<Ns...>) const {
731 return value_type(
732 deref_or_none(std::get<Ns>(iterators), std::get<Ns>(end_iterators))...);
733 }
734
735 template <size_t... Ns>
736 decltype(iterators) tup_inc(index_sequence<Ns...>) const {
737 return std::tuple<Iters...>(
738 next_or_end(std::get<Ns>(iterators), std::get<Ns>(end_iterators))...);
739 }
740
741public:
742 zip_longest_iterator(std::pair<Iters &&, Iters &&>... ts)
743 : iterators(std::forward<Iters>(ts.first)...),
744 end_iterators(std::forward<Iters>(ts.second)...) {}
745
746 value_type operator*() { return deref(index_sequence_for<Iters...>{}); }
747
748 value_type operator*() const { return deref(index_sequence_for<Iters...>{}); }
749
750 zip_longest_iterator<Iters...> &operator++() {
751 iterators = tup_inc(index_sequence_for<Iters...>{});
752 return *this;
753 }
754
755 bool operator==(const zip_longest_iterator<Iters...> &other) const {
756 return !test(other, index_sequence_for<Iters...>{});
757 }
758};
759
760template <typename... Args> class zip_longest_range {
761public:
762 using iterator =
763 zip_longest_iterator<decltype(adl_begin(std::declval<Args>()))...>;
764 using iterator_category = typename iterator::iterator_category;
765 using value_type = typename iterator::value_type;
766 using difference_type = typename iterator::difference_type;
767 using pointer = typename iterator::pointer;
768 using reference = typename iterator::reference;
769
770private:
771 std::tuple<Args...> ts;
772
773 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) const {
774 return iterator(std::make_pair(adl_begin(std::get<Ns>(ts)),
775 adl_end(std::get<Ns>(ts)))...);
776 }
777
778 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) const {
779 return iterator(std::make_pair(adl_end(std::get<Ns>(ts)),
780 adl_end(std::get<Ns>(ts)))...);
781 }
782
783public:
784 zip_longest_range(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
785
786 iterator begin() const { return begin_impl(index_sequence_for<Args...>{}); }
787 iterator end() const { return end_impl(index_sequence_for<Args...>{}); }
788};
789} // namespace detail
790
791/// Iterate over two or more iterators at the same time. Iteration continues
792/// until all iterators reach the end. The llvm::Optional only contains a value
793/// if the iterator has not reached the end.
794template <typename T, typename U, typename... Args>
795detail::zip_longest_range<T, U, Args...> zip_longest(T &&t, U &&u,
796 Args &&... args) {
797 return detail::zip_longest_range<T, U, Args...>(
798 std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
799}
800
801/// Iterator wrapper that concatenates sequences together.
802///
803/// This can concatenate different iterators, even with different types, into
804/// a single iterator provided the value types of all the concatenated
805/// iterators expose `reference` and `pointer` types that can be converted to
806/// `ValueT &` and `ValueT *` respectively. It doesn't support more
807/// interesting/customized pointer or reference types.
808///
809/// Currently this only supports forward or higher iterator categories as
810/// inputs and always exposes a forward iterator interface.
811template <typename ValueT, typename... IterTs>
812class concat_iterator
813 : public iterator_facade_base<concat_iterator<ValueT, IterTs...>,
814 std::forward_iterator_tag, ValueT> {
815 using BaseT = typename concat_iterator::iterator_facade_base;
816
817 /// We store both the current and end iterators for each concatenated
818 /// sequence in a tuple of pairs.
819 ///
820 /// Note that something like iterator_range seems nice at first here, but the
821 /// range properties are of little benefit and end up getting in the way
822 /// because we need to do mutation on the current iterators.
823 std::tuple<IterTs...> Begins;
824 std::tuple<IterTs...> Ends;
825
826 /// Attempts to increment a specific iterator.
827 ///
828 /// Returns true if it was able to increment the iterator. Returns false if
829 /// the iterator is already at the end iterator.
830 template <size_t Index> bool incrementHelper() {
831 auto &Begin = std::get<Index>(Begins);
832 auto &End = std::get<Index>(Ends);
833 if (Begin == End)
834 return false;
835
836 ++Begin;
837 return true;
838 }
839
840 /// Increments the first non-end iterator.
841 ///
842 /// It is an error to call this with all iterators at the end.
843 template <size_t... Ns> void increment(index_sequence<Ns...>) {
844 // Build a sequence of functions to increment each iterator if possible.
845 bool (concat_iterator::*IncrementHelperFns[])() = {
846 &concat_iterator::incrementHelper<Ns>...};
847
848 // Loop over them, and stop as soon as we succeed at incrementing one.
849 for (auto &IncrementHelperFn : IncrementHelperFns)
850 if ((this->*IncrementHelperFn)())
851 return;
852
853 llvm_unreachable("Attempted to increment an end concat iterator!")::llvm::llvm_unreachable_internal("Attempted to increment an end concat iterator!"
, "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/STLExtras.h"
, 853)
;
854 }
855
856 /// Returns null if the specified iterator is at the end. Otherwise,
857 /// dereferences the iterator and returns the address of the resulting
858 /// reference.
859 template <size_t Index> ValueT *getHelper() const {
860 auto &Begin = std::get<Index>(Begins);
861 auto &End = std::get<Index>(Ends);
862 if (Begin == End)
863 return nullptr;
864
865 return &*Begin;
866 }
867
868 /// Finds the first non-end iterator, dereferences, and returns the resulting
869 /// reference.
870 ///
871 /// It is an error to call this with all iterators at the end.
872 template <size_t... Ns> ValueT &get(index_sequence<Ns...>) const {
873 // Build a sequence of functions to get from iterator if possible.
874 ValueT *(concat_iterator::*GetHelperFns[])() const = {
875 &concat_iterator::getHelper<Ns>...};
876
877 // Loop over them, and return the first result we find.
878 for (auto &GetHelperFn : GetHelperFns)
879 if (ValueT *P = (this->*GetHelperFn)())
880 return *P;
881
882 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-9~svn362543/include/llvm/ADT/STLExtras.h"
, 882)
;
883 }
884
885public:
886 /// Constructs an iterator from a squence of ranges.
887 ///
888 /// We need the full range to know how to switch between each of the
889 /// iterators.
890 template <typename... RangeTs>
891 explicit concat_iterator(RangeTs &&... Ranges)
892 : Begins(std::begin(Ranges)...), Ends(std::end(Ranges)...) {}
893
894 using BaseT::operator++;
895
896 concat_iterator &operator++() {
897 increment(index_sequence_for<IterTs...>());
898 return *this;
899 }
900
901 ValueT &operator*() const { return get(index_sequence_for<IterTs...>()); }
902
903 bool operator==(const concat_iterator &RHS) const {
904 return Begins == RHS.Begins && Ends == RHS.Ends;
905 }
906};
907
908namespace detail {
909
910/// Helper to store a sequence of ranges being concatenated and access them.
911///
912/// This is designed to facilitate providing actual storage when temporaries
913/// are passed into the constructor such that we can use it as part of range
914/// based for loops.
915template <typename ValueT, typename... RangeTs> class concat_range {
916public:
917 using iterator =
918 concat_iterator<ValueT,
919 decltype(std::begin(std::declval<RangeTs &>()))...>;
920
921private:
922 std::tuple<RangeTs...> Ranges;
923
924 template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) {
925 return iterator(std::get<Ns>(Ranges)...);
926 }
927 template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) {
928 return iterator(make_range(std::end(std::get<Ns>(Ranges)),
929 std::end(std::get<Ns>(Ranges)))...);
930 }
931
932public:
933 concat_range(RangeTs &&... Ranges)
934 : Ranges(std::forward<RangeTs>(Ranges)...) {}
935
936 iterator begin() { return begin_impl(index_sequence_for<RangeTs...>{}); }
937 iterator end() { return end_impl(index_sequence_for<RangeTs...>{}); }
938};
939
940} // end namespace detail
941
942/// Concatenated range across two or more ranges.
943///
944/// The desired value type must be explicitly specified.
945template <typename ValueT, typename... RangeTs>
946detail::concat_range<ValueT, RangeTs...> concat(RangeTs &&... Ranges) {
947 static_assert(sizeof...(RangeTs) > 1,
948 "Need more than one range to concatenate!");
949 return detail::concat_range<ValueT, RangeTs...>(
950 std::forward<RangeTs>(Ranges)...);
951}
952
953//===----------------------------------------------------------------------===//
954// Extra additions to <utility>
955//===----------------------------------------------------------------------===//
956
957/// Function object to check whether the first component of a std::pair
958/// compares less than the first component of another std::pair.
959struct less_first {
960 template <typename T> bool operator()(const T &lhs, const T &rhs) const {
961 return lhs.first < rhs.first;
962 }
963};
964
965/// Function object to check whether the second component of a std::pair
966/// compares less than the second component of another std::pair.
967struct less_second {
968 template <typename T> bool operator()(const T &lhs, const T &rhs) const {
969 return lhs.second < rhs.second;
970 }
971};
972
973/// \brief Function object to apply a binary function to the first component of
974/// a std::pair.
975template<typename FuncTy>
976struct on_first {
977 FuncTy func;
978
979 template <typename T>
980 auto operator()(const T &lhs, const T &rhs) const
981 -> decltype(func(lhs.first, rhs.first)) {
982 return func(lhs.first, rhs.first);
983 }
984};
985
986// A subset of N3658. More stuff can be added as-needed.
987
988/// Represents a compile-time sequence of integers.
989template <class T, T... I> struct integer_sequence {
990 using value_type = T;
991
992 static constexpr size_t size() { return sizeof...(I); }
993};
994
995/// Alias for the common case of a sequence of size_ts.
996template <size_t... I>
997struct index_sequence : integer_sequence<std::size_t, I...> {};
998
999template <std::size_t N, std::size_t... I>
1000struct build_index_impl : build_index_impl<N - 1, N - 1, I...> {};
1001template <std::size_t... I>
1002struct build_index_impl<0, I...> : index_sequence<I...> {};
1003
1004/// Creates a compile-time integer sequence for a parameter pack.
1005template <class... Ts>
1006struct index_sequence_for : build_index_impl<sizeof...(Ts)> {};
1007
1008/// Utility type to build an inheritance chain that makes it easy to rank
1009/// overload candidates.
1010template <int N> struct rank : rank<N - 1> {};
1011template <> struct rank<0> {};
1012
1013/// traits class for checking whether type T is one of any of the given
1014/// types in the variadic list.
1015template <typename T, typename... Ts> struct is_one_of {
1016 static const bool value = false;
1017};
1018
1019template <typename T, typename U, typename... Ts>
1020struct is_one_of<T, U, Ts...> {
1021 static const bool value =
1022 std::is_same<T, U>::value || is_one_of<T, Ts...>::value;
1023};
1024
1025/// traits class for checking whether type T is a base class for all
1026/// the given types in the variadic list.
1027template <typename T, typename... Ts> struct are_base_of {
1028 static const bool value = true;
1029};
1030
1031template <typename T, typename U, typename... Ts>
1032struct are_base_of<T, U, Ts...> {
1033 static const bool value =
1034 std::is_base_of<T, U>::value && are_base_of<T, Ts...>::value;
1035};
1036
1037//===----------------------------------------------------------------------===//
1038// Extra additions for arrays
1039//===----------------------------------------------------------------------===//
1040
1041/// Find the length of an array.
1042template <class T, std::size_t N>
1043constexpr inline size_t array_lengthof(T (&)[N]) {
1044 return N;
1045}
1046
1047/// Adapt std::less<T> for array_pod_sort.
1048template<typename T>
1049inline int array_pod_sort_comparator(const void *P1, const void *P2) {
1050 if (std::less<T>()(*reinterpret_cast<const T*>(P1),
1051 *reinterpret_cast<const T*>(P2)))
1052 return -1;
1053 if (std::less<T>()(*reinterpret_cast<const T*>(P2),
1054 *reinterpret_cast<const T*>(P1)))
1055 return 1;
1056 return 0;
1057}
1058
1059/// get_array_pod_sort_comparator - This is an internal helper function used to
1060/// get type deduction of T right.
1061template<typename T>
1062inline int (*get_array_pod_sort_comparator(const T &))
1063 (const void*, const void*) {
1064 return array_pod_sort_comparator<T>;
1065}
1066
1067/// array_pod_sort - This sorts an array with the specified start and end
1068/// extent. This is just like std::sort, except that it calls qsort instead of
1069/// using an inlined template. qsort is slightly slower than std::sort, but
1070/// most sorts are not performance critical in LLVM and std::sort has to be
1071/// template instantiated for each type, leading to significant measured code
1072/// bloat. This function should generally be used instead of std::sort where
1073/// possible.
1074///
1075/// This function assumes that you have simple POD-like types that can be
1076/// compared with std::less and can be moved with memcpy. If this isn't true,
1077/// you should use std::sort.
1078///
1079/// NOTE: If qsort_r were portable, we could allow a custom comparator and
1080/// default to std::less.
1081template<class IteratorTy>
1082inline void array_pod_sort(IteratorTy Start, IteratorTy End) {
1083 // Don't inefficiently call qsort with one element or trigger undefined
1084 // behavior with an empty sequence.
1085 auto NElts = End - Start;
1086 if (NElts <= 1) return;
1087#ifdef EXPENSIVE_CHECKS
1088 std::mt19937 Generator(std::random_device{}());
1089 std::shuffle(Start, End, Generator);
1090#endif
1091 qsort(&*Start, NElts, sizeof(*Start), get_array_pod_sort_comparator(*Start));
1092}
1093
1094template <class IteratorTy>
1095inline void array_pod_sort(
1096 IteratorTy Start, IteratorTy End,
1097 int (*Compare)(
1098 const typename std::iterator_traits<IteratorTy>::value_type *,
1099 const typename std::iterator_traits<IteratorTy>::value_type *)) {
1100 // Don't inefficiently call qsort with one element or trigger undefined
1101 // behavior with an empty sequence.
1102 auto NElts = End - Start;
1103 if (NElts <= 1) return;
1104#ifdef EXPENSIVE_CHECKS
1105 std::mt19937 Generator(std::random_device{}());
1106 std::shuffle(Start, End, Generator);
1107#endif
1108 qsort(&*Start, NElts, sizeof(*Start),
1109 reinterpret_cast<int (*)(const void *, const void *)>(Compare));
1110}
1111
1112// Provide wrappers to std::sort which shuffle the elements before sorting
1113// to help uncover non-deterministic behavior (PR35135).
1114template <typename IteratorTy>
1115inline void sort(IteratorTy Start, IteratorTy End) {
1116#ifdef EXPENSIVE_CHECKS
1117 std::mt19937 Generator(std::random_device{}());
1118 std::shuffle(Start, End, Generator);
1119#endif
1120 std::sort(Start, End);
1121}
1122
1123template <typename Container> inline void sort(Container &&C) {
1124 llvm::sort(adl_begin(C), adl_end(C));
1125}
1126
1127template <typename IteratorTy, typename Compare>
1128inline void sort(IteratorTy Start, IteratorTy End, Compare Comp) {
1129#ifdef EXPENSIVE_CHECKS
1130 std::mt19937 Generator(std::random_device{}());
1131 std::shuffle(Start, End, Generator);
1132#endif
1133 std::sort(Start, End, Comp);
1134}
1135
1136template <typename Container, typename Compare>
1137inline void sort(Container &&C, Compare Comp) {
1138 llvm::sort(adl_begin(C), adl_end(C), Comp);
1139}
1140
1141//===----------------------------------------------------------------------===//
1142// Extra additions to <algorithm>
1143//===----------------------------------------------------------------------===//
1144
1145/// For a container of pointers, deletes the pointers and then clears the
1146/// container.
1147template<typename Container>
1148void DeleteContainerPointers(Container &C) {
1149 for (auto V : C)
1150 delete V;
1151 C.clear();
1152}
1153
1154/// In a container of pairs (usually a map) whose second element is a pointer,
1155/// deletes the second elements and then clears the container.
1156template<typename Container>
1157void DeleteContainerSeconds(Container &C) {
1158 for (auto &V : C)
1159 delete V.second;
1160 C.clear();
1161}
1162
1163/// Get the size of a range. This is a wrapper function around std::distance
1164/// which is only enabled when the operation is O(1).
1165template <typename R>
1166auto size(R &&Range, typename std::enable_if<
1167 std::is_same<typename std::iterator_traits<decltype(
1168 Range.begin())>::iterator_category,
1169 std::random_access_iterator_tag>::value,
1170 void>::type * = nullptr)
1171 -> decltype(std::distance(Range.begin(), Range.end())) {
1172 return std::distance(Range.begin(), Range.end());
1173}
1174
1175/// Provide wrappers to std::for_each which take ranges instead of having to
1176/// pass begin/end explicitly.
1177template <typename R, typename UnaryPredicate>
1178UnaryPredicate for_each(R &&Range, UnaryPredicate P) {
1179 return std::for_each(adl_begin(Range), adl_end(Range), P);
1180}
1181
1182/// Provide wrappers to std::all_of which take ranges instead of having to pass
1183/// begin/end explicitly.
1184template <typename R, typename UnaryPredicate>
1185bool all_of(R &&Range, UnaryPredicate P) {
1186 return std::all_of(adl_begin(Range), adl_end(Range), P);
1187}
1188
1189/// Provide wrappers to std::any_of which take ranges instead of having to pass
1190/// begin/end explicitly.
1191template <typename R, typename UnaryPredicate>
1192bool any_of(R &&Range, UnaryPredicate P) {
1193 return std::any_of(adl_begin(Range), adl_end(Range), P);
1194}
1195
1196/// Provide wrappers to std::none_of which take ranges instead of having to pass
1197/// begin/end explicitly.
1198template <typename R, typename UnaryPredicate>
1199bool none_of(R &&Range, UnaryPredicate P) {
1200 return std::none_of(adl_begin(Range), adl_end(Range), P);
1201}
1202
1203/// Provide wrappers to std::find which take ranges instead of having to pass
1204/// begin/end explicitly.
1205template <typename R, typename T>
1206auto find(R &&Range, const T &Val) -> decltype(adl_begin(Range)) {
1207 return std::find(adl_begin(Range), adl_end(Range), Val);
1208}
1209
1210/// Provide wrappers to std::find_if which take ranges instead of having to pass
1211/// begin/end explicitly.
1212template <typename R, typename UnaryPredicate>
1213auto find_if(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1214 return std::find_if(adl_begin(Range), adl_end(Range), P);
1215}
1216
1217template <typename R, typename UnaryPredicate>
1218auto find_if_not(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1219 return std::find_if_not(adl_begin(Range), adl_end(Range), P);
1220}
1221
1222/// Provide wrappers to std::remove_if which take ranges instead of having to
1223/// pass begin/end explicitly.
1224template <typename R, typename UnaryPredicate>
1225auto remove_if(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1226 return std::remove_if(adl_begin(Range), adl_end(Range), P);
1227}
1228
1229/// Provide wrappers to std::copy_if which take ranges instead of having to
1230/// pass begin/end explicitly.
1231template <typename R, typename OutputIt, typename UnaryPredicate>
1232OutputIt copy_if(R &&Range, OutputIt Out, UnaryPredicate P) {
1233 return std::copy_if(adl_begin(Range), adl_end(Range), Out, P);
1234}
1235
1236template <typename R, typename OutputIt>
1237OutputIt copy(R &&Range, OutputIt Out) {
1238 return std::copy(adl_begin(Range), adl_end(Range), Out);
1239}
1240
1241/// Wrapper function around std::find to detect if an element exists
1242/// in a container.
1243template <typename R, typename E>
1244bool is_contained(R &&Range, const E &Element) {
1245 return std::find(adl_begin(Range), adl_end(Range), Element) != adl_end(Range);
1246}
1247
1248/// Wrapper function around std::count to count the number of times an element
1249/// \p Element occurs in the given range \p Range.
1250template <typename R, typename E>
1251auto count(R &&Range, const E &Element) ->
1252 typename std::iterator_traits<decltype(adl_begin(Range))>::difference_type {
1253 return std::count(adl_begin(Range), adl_end(Range), Element);
1254}
1255
1256/// Wrapper function around std::count_if to count the number of times an
1257/// element satisfying a given predicate occurs in a range.
1258template <typename R, typename UnaryPredicate>
1259auto count_if(R &&Range, UnaryPredicate P) ->
1260 typename std::iterator_traits<decltype(adl_begin(Range))>::difference_type {
1261 return std::count_if(adl_begin(Range), adl_end(Range), P);
1262}
1263
1264/// Wrapper function around std::transform to apply a function to a range and
1265/// store the result elsewhere.
1266template <typename R, typename OutputIt, typename UnaryPredicate>
1267OutputIt transform(R &&Range, OutputIt d_first, UnaryPredicate P) {
1268 return std::transform(adl_begin(Range), adl_end(Range), d_first, P);
1269}
1270
1271/// Provide wrappers to std::partition which take ranges instead of having to
1272/// pass begin/end explicitly.
1273template <typename R, typename UnaryPredicate>
1274auto partition(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1275 return std::partition(adl_begin(Range), adl_end(Range), P);
1276}
1277
1278/// Provide wrappers to std::lower_bound which take ranges instead of having to
1279/// pass begin/end explicitly.
1280template <typename R, typename T>
1281auto lower_bound(R &&Range, T &&Value) -> decltype(adl_begin(Range)) {
1282 return std::lower_bound(adl_begin(Range), adl_end(Range),
1283 std::forward<T>(Value));
1284}
1285
1286template <typename R, typename T, typename Compare>
1287auto lower_bound(R &&Range, T &&Value, Compare C)
1288 -> decltype(adl_begin(Range)) {
1289 return std::lower_bound(adl_begin(Range), adl_end(Range),
1290 std::forward<T>(Value), C);
1291}
1292
1293/// Provide wrappers to std::upper_bound which take ranges instead of having to
1294/// pass begin/end explicitly.
1295template <typename R, typename T>
1296auto upper_bound(R &&Range, T &&Value) -> decltype(adl_begin(Range)) {
1297 return std::upper_bound(adl_begin(Range), adl_end(Range),
1298 std::forward<T>(Value));
1299}
1300
1301template <typename R, typename T, typename Compare>
1302auto upper_bound(R &&Range, T &&Value, Compare C)
1303 -> decltype(adl_begin(Range)) {
1304 return std::upper_bound(adl_begin(Range), adl_end(Range),
1305 std::forward<T>(Value), C);
1306}
1307
1308template <typename R>
1309void stable_sort(R &&Range) {
1310 std::stable_sort(adl_begin(Range), adl_end(Range));
1311}
1312
1313template <typename R, typename Compare>
1314void stable_sort(R &&Range, Compare C) {
1315 std::stable_sort(adl_begin(Range), adl_end(Range), C);
1316}
1317
1318/// Binary search for the first index where a predicate is true.
1319/// Returns the first I in [Lo, Hi) where C(I) is true, or Hi if it never is.
1320/// Requires that C is always false below some limit, and always true above it.
1321///
1322/// Example:
1323/// size_t DawnModernEra = bsearch(1776, 2050, [](size_t Year){
1324/// return Presidents.for(Year).twitterHandle() != None;
1325/// });
1326///
1327/// Note the return value differs from std::binary_search!
1328template <typename Predicate>
1329size_t bsearch(size_t Lo, size_t Hi, Predicate P) {
1330 while (Lo != Hi) {
1331 assert(Hi > Lo)((Hi > Lo) ? static_cast<void> (0) : __assert_fail (
"Hi > Lo", "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/STLExtras.h"
, 1331, __PRETTY_FUNCTION__))
;
1332 size_t Mid = Lo + (Hi - Lo) / 2;
1333 if (P(Mid))
1334 Hi = Mid;
1335 else
1336 Lo = Mid + 1;
1337 }
1338 return Hi;
1339}
1340
1341/// Binary search for the first iterator where a predicate is true.
1342/// Returns the first I in [Lo, Hi) where C(*I) is true, or Hi if it never is.
1343/// Requires that C is always false below some limit, and always true above it.
1344template <typename It, typename Predicate,
1345 typename Val = decltype(*std::declval<It>())>
1346It bsearch(It Lo, It Hi, Predicate P) {
1347 return std::lower_bound(Lo, Hi, 0u,
1348 [&](const Val &V, unsigned) { return !P(V); });
1349}
1350
1351/// Binary search for the first iterator in a range where a predicate is true.
1352/// Requires that C is always false below some limit, and always true above it.
1353template <typename R, typename Predicate>
1354auto bsearch(R &&Range, Predicate P) -> decltype(adl_begin(Range)) {
1355 return bsearch(adl_begin(Range), adl_end(Range), P);
1356}
1357
1358/// Wrapper function around std::equal to detect if all elements
1359/// in a container are same.
1360template <typename R>
1361bool is_splat(R &&Range) {
1362 size_t range_size = size(Range);
1363 return range_size != 0 && (range_size == 1 ||
1364 std::equal(adl_begin(Range) + 1, adl_end(Range), adl_begin(Range)));
1365}
1366
1367/// Given a range of type R, iterate the entire range and return a
1368/// SmallVector with elements of the vector. This is useful, for example,
1369/// when you want to iterate a range and then sort the results.
1370template <unsigned Size, typename R>
1371SmallVector<typename std::remove_const<detail::ValueOfRange<R>>::type, Size>
1372to_vector(R &&Range) {
1373 return {adl_begin(Range), adl_end(Range)};
1374}
1375
1376/// Provide a container algorithm similar to C++ Library Fundamentals v2's
1377/// `erase_if` which is equivalent to:
1378///
1379/// C.erase(remove_if(C, pred), C.end());
1380///
1381/// This version works for any container with an erase method call accepting
1382/// two iterators.
1383template <typename Container, typename UnaryPredicate>
1384void erase_if(Container &C, UnaryPredicate P) {
1385 C.erase(remove_if(C, P), C.end());
1386}
1387
1388//===----------------------------------------------------------------------===//
1389// Extra additions to <memory>
1390//===----------------------------------------------------------------------===//
1391
1392// Implement make_unique according to N3656.
1393
1394/// Constructs a `new T()` with the given args and returns a
1395/// `unique_ptr<T>` which owns the object.
1396///
1397/// Example:
1398///
1399/// auto p = make_unique<int>();
1400/// auto p = make_unique<std::tuple<int, int>>(0, 1);
1401template <class T, class... Args>
1402typename std::enable_if<!std::is_array<T>::value, std::unique_ptr<T>>::type
1403make_unique(Args &&... args) {
1404 return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
7
Memory is allocated
1405}
1406
1407/// Constructs a `new T[n]` with the given args and returns a
1408/// `unique_ptr<T[]>` which owns the object.
1409///
1410/// \param n size of the new array.
1411///
1412/// Example:
1413///
1414/// auto p = make_unique<int[]>(2); // value-initializes the array with 0's.
1415template <class T>
1416typename std::enable_if<std::is_array<T>::value && std::extent<T>::value == 0,
1417 std::unique_ptr<T>>::type
1418make_unique(size_t n) {
1419 return std::unique_ptr<T>(new typename std::remove_extent<T>::type[n]());
1420}
1421
1422/// This function isn't used and is only here to provide better compile errors.
1423template <class T, class... Args>
1424typename std::enable_if<std::extent<T>::value != 0>::type
1425make_unique(Args &&...) = delete;
1426
1427struct FreeDeleter {
1428 void operator()(void* v) {
1429 ::free(v);
1430 }
1431};
1432
1433template<typename First, typename Second>
1434struct pair_hash {
1435 size_t operator()(const std::pair<First, Second> &P) const {
1436 return std::hash<First>()(P.first) * 31 + std::hash<Second>()(P.second);
1437 }
1438};
1439
1440/// A functor like C++14's std::less<void> in its absence.
1441struct less {
1442 template <typename A, typename B> bool operator()(A &&a, B &&b) const {
1443 return std::forward<A>(a) < std::forward<B>(b);
1444 }
1445};
1446
1447/// A functor like C++14's std::equal<void> in its absence.
1448struct equal {
1449 template <typename A, typename B> bool operator()(A &&a, B &&b) const {
1450 return std::forward<A>(a) == std::forward<B>(b);
1451 }
1452};
1453
1454/// Binary functor that adapts to any other binary functor after dereferencing
1455/// operands.
1456template <typename T> struct deref {
1457 T func;
1458
1459 // Could be further improved to cope with non-derivable functors and
1460 // non-binary functors (should be a variadic template member function
1461 // operator()).
1462 template <typename A, typename B>
1463 auto operator()(A &lhs, B &rhs) const -> decltype(func(*lhs, *rhs)) {
1464 assert(lhs)((lhs) ? static_cast<void> (0) : __assert_fail ("lhs", "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/STLExtras.h"
, 1464, __PRETTY_FUNCTION__))
;
1465 assert(rhs)((rhs) ? static_cast<void> (0) : __assert_fail ("rhs", "/build/llvm-toolchain-snapshot-9~svn362543/include/llvm/ADT/STLExtras.h"
, 1465, __PRETTY_FUNCTION__))
;
1466 return func(*lhs, *rhs);
1467 }
1468};
1469
1470namespace detail {
1471
1472template <typename R> class enumerator_iter;
1473
1474template <typename R> struct result_pair {
1475 friend class enumerator_iter<R>;
1476
1477 result_pair() = default;
1478 result_pair(std::size_t Index, IterOfRange<R> Iter)
1479 : Index(Index), Iter(Iter) {}
1480
1481 result_pair<R> &operator=(const result_pair<R> &Other) {
1482 Index = Other.Index;
1483 Iter = Other.Iter;
1484 return *this;
1485 }
1486
1487 std::size_t index() const { return Index; }
1488 const ValueOfRange<R> &value() const { return *Iter; }
1489 ValueOfRange<R> &value() { return *Iter; }
1490
1491private:
1492 std::size_t Index = std::numeric_limits<std::size_t>::max();
1493 IterOfRange<R> Iter;
1494};
1495
1496template <typename R>
1497class enumerator_iter
1498 : public iterator_facade_base<
1499 enumerator_iter<R>, std::forward_iterator_tag, result_pair<R>,
1500 typename std::iterator_traits<IterOfRange<R>>::difference_type,
1501 typename std::iterator_traits<IterOfRange<R>>::pointer,
1502 typename std::iterator_traits<IterOfRange<R>>::reference> {
1503 using result_type = result_pair<R>;
1504
1505public:
1506 explicit enumerator_iter(IterOfRange<R> EndIter)
1507 : Result(std::numeric_limits<size_t>::max(), EndIter) {}
1508
1509 enumerator_iter(std::size_t Index, IterOfRange<R> Iter)
1510 : Result(Index, Iter) {}
1511
1512 result_type &operator*() { return Result; }
1513 const result_type &operator*() const { return Result; }
1514
1515 enumerator_iter<R> &operator++() {
1516 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-9~svn362543/include/llvm/ADT/STLExtras.h"
, 1516, __PRETTY_FUNCTION__))
;
1517 ++Result.Iter;
1518 ++Result.Index;
1519 return *this;
1520 }
1521
1522 bool operator==(const enumerator_iter<R> &RHS) const {
1523 // Don't compare indices here, only iterators. It's possible for an end
1524 // iterator to have different indices depending on whether it was created
1525 // by calling std::end() versus incrementing a valid iterator.
1526 return Result.Iter == RHS.Result.Iter;
1527 }
1528
1529 enumerator_iter<R> &operator=(const enumerator_iter<R> &Other) {
1530 Result = Other.Result;
1531 return *this;
1532 }
1533
1534private:
1535 result_type Result;
1536};
1537
1538template <typename R> class enumerator {
1539public:
1540 explicit enumerator(R &&Range) : TheRange(std::forward<R>(Range)) {}
1541
1542 enumerator_iter<R> begin() {
1543 return enumerator_iter<R>(0, std::begin(TheRange));
1544 }
1545
1546 enumerator_iter<R> end() {
1547 return enumerator_iter<R>(std::end(TheRange));
1548 }
1549
1550private:
1551 R TheRange;
1552};
1553
1554} // end namespace detail
1555
1556/// Given an input range, returns a new range whose values are are pair (A,B)
1557/// such that A is the 0-based index of the item in the sequence, and B is
1558/// the value from the original sequence. Example:
1559///
1560/// std::vector<char> Items = {'A', 'B', 'C', 'D'};
1561/// for (auto X : enumerate(Items)) {
1562/// printf("Item %d - %c\n", X.index(), X.value());
1563/// }
1564///
1565/// Output:
1566/// Item 0 - A
1567/// Item 1 - B
1568/// Item 2 - C
1569/// Item 3 - D
1570///
1571template <typename R> detail::enumerator<R> enumerate(R &&TheRange) {
1572 return detail::enumerator<R>(std::forward<R>(TheRange));
1573}
1574
1575namespace detail {
1576
1577template <typename F, typename Tuple, std::size_t... I>
1578auto apply_tuple_impl(F &&f, Tuple &&t, index_sequence<I...>)
1579 -> decltype(std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...)) {
1580 return std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...);
1581}
1582
1583} // end namespace detail
1584
1585/// Given an input tuple (a1, a2, ..., an), pass the arguments of the
1586/// tuple variadically to f as if by calling f(a1, a2, ..., an) and
1587/// return the result.
1588template <typename F, typename Tuple>
1589auto apply_tuple(F &&f, Tuple &&t) -> decltype(detail::apply_tuple_impl(
1590 std::forward<F>(f), std::forward<Tuple>(t),
1591 build_index_impl<
1592 std::tuple_size<typename std::decay<Tuple>::type>::value>{})) {
1593 using Indices = build_index_impl<
1594 std::tuple_size<typename std::decay<Tuple>::type>::value>;
1595
1596 return detail::apply_tuple_impl(std::forward<F>(f), std::forward<Tuple>(t),
1597 Indices{});
1598}
1599
1600/// Return true if the sequence [Begin, End) has exactly N items. Runs in O(N)
1601/// time. Not meant for use with random-access iterators.
1602template <typename IterTy>
1603bool hasNItems(
1604 IterTy &&Begin, IterTy &&End, unsigned N,
1605 typename std::enable_if<
1606 !std::is_same<
1607 typename std::iterator_traits<typename std::remove_reference<
1608 decltype(Begin)>::type>::iterator_category,
1609 std::random_access_iterator_tag>::value,
1610 void>::type * = nullptr) {
1611 for (; N; --N, ++Begin)
1612 if (Begin == End)
1613 return false; // Too few.
1614 return Begin == End;
1615}
1616
1617/// Return true if the sequence [Begin, End) has N or more items. Runs in O(N)
1618/// time. Not meant for use with random-access iterators.
1619template <typename IterTy>
1620bool hasNItemsOrMore(
1621 IterTy &&Begin, IterTy &&End, unsigned N,
1622 typename std::enable_if<
1623 !std::is_same<
1624 typename std::iterator_traits<typename std::remove_reference<
1625 decltype(Begin)>::type>::iterator_category,
1626 std::random_access_iterator_tag>::value,
1627 void>::type * = nullptr) {
1628 for (; N; --N, ++Begin)
1629 if (Begin == End)
1630 return false; // Too few.
1631 return true;
1632}
1633
1634/// Returns a raw pointer that represents the same address as the argument.
1635///
1636/// The late bound return should be removed once we move to C++14 to better
1637/// align with the C++20 declaration. Also, this implementation can be removed
1638/// once we move to C++20 where it's defined as std::to_addres()
1639///
1640/// The std::pointer_traits<>::to_address(p) variations of these overloads has
1641/// not been implemented.
1642template <class Ptr> auto to_address(const Ptr &P) -> decltype(P.operator->()) {
1643 return P.operator->();
1644}
1645template <class T> constexpr T *to_address(T *P) { return P; }
1646
1647} // end namespace llvm
1648
1649#endif // LLVM_ADT_STLEXTRAS_H