Bug Summary

File:lib/Bitcode/Reader/MetadataLoader.cpp
Warning:line 210, column 39
The result of the right shift is undefined due to shifting by '64', which is greater or equal to the width of type 'llvm::SimpleBitstreamCursor::word_t'

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-eagerly-assume -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -mrelocation-model pic -pic-level 2 -mthread-model posix -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-7/lib/clang/7.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-7~svn325118/build-llvm/lib/Bitcode/Reader -I /build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader -I /build/llvm-toolchain-snapshot-7~svn325118/build-llvm/include -I /build/llvm-toolchain-snapshot-7~svn325118/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/x86_64-linux-gnu/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/x86_64-linux-gnu/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/c++/7.3.0/backward -internal-isystem /usr/include/clang/7.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-7/lib/clang/7.0.0/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-7~svn325118/build-llvm/lib/Bitcode/Reader -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-checker optin.performance.Padding -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-02-14-150435-17243-1 -x c++ /build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp

/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp

1//===- MetadataLoader.cpp - Internal BitcodeReader implementation ---------===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#include "MetadataLoader.h"
11#include "ValueList.h"
12
13#include "llvm/ADT/APFloat.h"
14#include "llvm/ADT/APInt.h"
15#include "llvm/ADT/ArrayRef.h"
16#include "llvm/ADT/DenseMap.h"
17#include "llvm/ADT/DenseSet.h"
18#include "llvm/ADT/None.h"
19#include "llvm/ADT/STLExtras.h"
20#include "llvm/ADT/SmallString.h"
21#include "llvm/ADT/SmallVector.h"
22#include "llvm/ADT/Statistic.h"
23#include "llvm/ADT/StringRef.h"
24#include "llvm/ADT/Twine.h"
25#include "llvm/Bitcode/BitcodeReader.h"
26#include "llvm/Bitcode/BitstreamReader.h"
27#include "llvm/Bitcode/LLVMBitCodes.h"
28#include "llvm/IR/Argument.h"
29#include "llvm/IR/Attributes.h"
30#include "llvm/IR/AutoUpgrade.h"
31#include "llvm/IR/BasicBlock.h"
32#include "llvm/IR/CallingConv.h"
33#include "llvm/IR/Comdat.h"
34#include "llvm/IR/Constant.h"
35#include "llvm/IR/Constants.h"
36#include "llvm/IR/DebugInfo.h"
37#include "llvm/IR/DebugInfoMetadata.h"
38#include "llvm/IR/DebugLoc.h"
39#include "llvm/IR/DerivedTypes.h"
40#include "llvm/IR/DiagnosticPrinter.h"
41#include "llvm/IR/Function.h"
42#include "llvm/IR/GVMaterializer.h"
43#include "llvm/IR/GlobalAlias.h"
44#include "llvm/IR/GlobalIFunc.h"
45#include "llvm/IR/GlobalIndirectSymbol.h"
46#include "llvm/IR/GlobalObject.h"
47#include "llvm/IR/GlobalValue.h"
48#include "llvm/IR/GlobalVariable.h"
49#include "llvm/IR/InlineAsm.h"
50#include "llvm/IR/InstrTypes.h"
51#include "llvm/IR/Instruction.h"
52#include "llvm/IR/Instructions.h"
53#include "llvm/IR/IntrinsicInst.h"
54#include "llvm/IR/Intrinsics.h"
55#include "llvm/IR/LLVMContext.h"
56#include "llvm/IR/Module.h"
57#include "llvm/IR/ModuleSummaryIndex.h"
58#include "llvm/IR/OperandTraits.h"
59#include "llvm/IR/TrackingMDRef.h"
60#include "llvm/IR/Type.h"
61#include "llvm/IR/ValueHandle.h"
62#include "llvm/Support/AtomicOrdering.h"
63#include "llvm/Support/Casting.h"
64#include "llvm/Support/CommandLine.h"
65#include "llvm/Support/Compiler.h"
66#include "llvm/Support/Debug.h"
67#include "llvm/Support/Error.h"
68#include "llvm/Support/ErrorHandling.h"
69#include "llvm/Support/ManagedStatic.h"
70#include "llvm/Support/MemoryBuffer.h"
71#include "llvm/Support/raw_ostream.h"
72#include <algorithm>
73#include <cassert>
74#include <cstddef>
75#include <cstdint>
76#include <deque>
77#include <limits>
78#include <map>
79#include <memory>
80#include <string>
81#include <system_error>
82#include <tuple>
83#include <utility>
84#include <vector>
85
86using namespace llvm;
87
88#define DEBUG_TYPE"bitcode-reader" "bitcode-reader"
89
90STATISTIC(NumMDStringLoaded, "Number of MDStrings loaded")static llvm::Statistic NumMDStringLoaded = {"bitcode-reader",
"NumMDStringLoaded", "Number of MDStrings loaded", {0}, {false
}}
;
91STATISTIC(NumMDNodeTemporary, "Number of MDNode::Temporary created")static llvm::Statistic NumMDNodeTemporary = {"bitcode-reader"
, "NumMDNodeTemporary", "Number of MDNode::Temporary created"
, {0}, {false}}
;
92STATISTIC(NumMDRecordLoaded, "Number of Metadata records loaded")static llvm::Statistic NumMDRecordLoaded = {"bitcode-reader",
"NumMDRecordLoaded", "Number of Metadata records loaded", {0
}, {false}}
;
93
94/// Flag whether we need to import full type definitions for ThinLTO.
95/// Currently needed for Darwin and LLDB.
96static cl::opt<bool> ImportFullTypeDefinitions(
97 "import-full-type-definitions", cl::init(false), cl::Hidden,
98 cl::desc("Import full type definitions for ThinLTO."));
99
100static cl::opt<bool> DisableLazyLoading(
101 "disable-ondemand-mds-loading", cl::init(false), cl::Hidden,
102 cl::desc("Force disable the lazy-loading on-demand of metadata when "
103 "loading bitcode for importing."));
104
105namespace {
106
107static int64_t unrotateSign(uint64_t U) { return U & 1 ? ~(U >> 1) : U >> 1; }
108
109class BitcodeReaderMetadataList {
110 /// Array of metadata references.
111 ///
112 /// Don't use std::vector here. Some versions of libc++ copy (instead of
113 /// move) on resize, and TrackingMDRef is very expensive to copy.
114 SmallVector<TrackingMDRef, 1> MetadataPtrs;
115
116 /// The set of indices in MetadataPtrs above of forward references that were
117 /// generated.
118 SmallDenseSet<unsigned, 1> ForwardReference;
119
120 /// The set of indices in MetadataPtrs above of Metadata that need to be
121 /// resolved.
122 SmallDenseSet<unsigned, 1> UnresolvedNodes;
123
124 /// Structures for resolving old type refs.
125 struct {
126 SmallDenseMap<MDString *, TempMDTuple, 1> Unknown;
127 SmallDenseMap<MDString *, DICompositeType *, 1> Final;
128 SmallDenseMap<MDString *, DICompositeType *, 1> FwdDecls;
129 SmallVector<std::pair<TrackingMDRef, TempMDTuple>, 1> Arrays;
130 } OldTypeRefs;
131
132 LLVMContext &Context;
133
134public:
135 BitcodeReaderMetadataList(LLVMContext &C) : Context(C) {}
136
137 // vector compatibility methods
138 unsigned size() const { return MetadataPtrs.size(); }
139 void resize(unsigned N) { MetadataPtrs.resize(N); }
140 void push_back(Metadata *MD) { MetadataPtrs.emplace_back(MD); }
141 void clear() { MetadataPtrs.clear(); }
142 Metadata *back() const { return MetadataPtrs.back(); }
143 void pop_back() { MetadataPtrs.pop_back(); }
144 bool empty() const { return MetadataPtrs.empty(); }
145
146 Metadata *operator[](unsigned i) const {
147 assert(i < MetadataPtrs.size())(static_cast <bool> (i < MetadataPtrs.size()) ? void
(0) : __assert_fail ("i < MetadataPtrs.size()", "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 147, __extension__ __PRETTY_FUNCTION__))
;
148 return MetadataPtrs[i];
149 }
150
151 Metadata *lookup(unsigned I) const {
152 if (I < MetadataPtrs.size())
153 return MetadataPtrs[I];
154 return nullptr;
155 }
156
157 void shrinkTo(unsigned N) {
158 assert(N <= size() && "Invalid shrinkTo request!")(static_cast <bool> (N <= size() && "Invalid shrinkTo request!"
) ? void (0) : __assert_fail ("N <= size() && \"Invalid shrinkTo request!\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 158, __extension__ __PRETTY_FUNCTION__))
;
159 assert(ForwardReference.empty() && "Unexpected forward refs")(static_cast <bool> (ForwardReference.empty() &&
"Unexpected forward refs") ? void (0) : __assert_fail ("ForwardReference.empty() && \"Unexpected forward refs\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 159, __extension__ __PRETTY_FUNCTION__))
;
160 assert(UnresolvedNodes.empty() && "Unexpected unresolved node")(static_cast <bool> (UnresolvedNodes.empty() &&
"Unexpected unresolved node") ? void (0) : __assert_fail ("UnresolvedNodes.empty() && \"Unexpected unresolved node\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 160, __extension__ __PRETTY_FUNCTION__))
;
161 MetadataPtrs.resize(N);
162 }
163
164 /// Return the given metadata, creating a replaceable forward reference if
165 /// necessary.
166 Metadata *getMetadataFwdRef(unsigned Idx);
167
168 /// Return the given metadata only if it is fully resolved.
169 ///
170 /// Gives the same result as \a lookup(), unless \a MDNode::isResolved()
171 /// would give \c false.
172 Metadata *getMetadataIfResolved(unsigned Idx);
173
174 MDNode *getMDNodeFwdRefOrNull(unsigned Idx);
175 void assignValue(Metadata *MD, unsigned Idx);
176 void tryToResolveCycles();
177 bool hasFwdRefs() const { return !ForwardReference.empty(); }
178 int getNextFwdRef() {
179 assert(hasFwdRefs())(static_cast <bool> (hasFwdRefs()) ? void (0) : __assert_fail
("hasFwdRefs()", "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 179, __extension__ __PRETTY_FUNCTION__))
;
180 return *ForwardReference.begin();
181 }
182
183 /// Upgrade a type that had an MDString reference.
184 void addTypeRef(MDString &UUID, DICompositeType &CT);
185
186 /// Upgrade a type that had an MDString reference.
187 Metadata *upgradeTypeRef(Metadata *MaybeUUID);
188
189 /// Upgrade a type ref array that may have MDString references.
190 Metadata *upgradeTypeRefArray(Metadata *MaybeTuple);
191
192private:
193 Metadata *resolveTypeRefArray(Metadata *MaybeTuple);
194};
195
196void BitcodeReaderMetadataList::assignValue(Metadata *MD, unsigned Idx) {
197 if (auto *MDN = dyn_cast<MDNode>(MD))
198 if (!MDN->isResolved())
199 UnresolvedNodes.insert(Idx);
200
201 if (Idx == size()) {
202 push_back(MD);
203 return;
204 }
205
206 if (Idx >= size())
207 resize(Idx + 1);
208
209 TrackingMDRef &OldMD = MetadataPtrs[Idx];
210 if (!OldMD) {
211 OldMD.reset(MD);
212 return;
213 }
214
215 // If there was a forward reference to this value, replace it.
216 TempMDTuple PrevMD(cast<MDTuple>(OldMD.get()));
217 PrevMD->replaceAllUsesWith(MD);
218 ForwardReference.erase(Idx);
219}
220
221Metadata *BitcodeReaderMetadataList::getMetadataFwdRef(unsigned Idx) {
222 if (Idx >= size())
223 resize(Idx + 1);
224
225 if (Metadata *MD = MetadataPtrs[Idx])
226 return MD;
227
228 // Track forward refs to be resolved later.
229 ForwardReference.insert(Idx);
230
231 // Create and return a placeholder, which will later be RAUW'd.
232 ++NumMDNodeTemporary;
233 Metadata *MD = MDNode::getTemporary(Context, None).release();
234 MetadataPtrs[Idx].reset(MD);
235 return MD;
236}
237
238Metadata *BitcodeReaderMetadataList::getMetadataIfResolved(unsigned Idx) {
239 Metadata *MD = lookup(Idx);
240 if (auto *N = dyn_cast_or_null<MDNode>(MD))
241 if (!N->isResolved())
242 return nullptr;
243 return MD;
244}
245
246MDNode *BitcodeReaderMetadataList::getMDNodeFwdRefOrNull(unsigned Idx) {
247 return dyn_cast_or_null<MDNode>(getMetadataFwdRef(Idx));
248}
249
250void BitcodeReaderMetadataList::tryToResolveCycles() {
251 if (!ForwardReference.empty())
252 // Still forward references... can't resolve cycles.
253 return;
254
255 // Give up on finding a full definition for any forward decls that remain.
256 for (const auto &Ref : OldTypeRefs.FwdDecls)
257 OldTypeRefs.Final.insert(Ref);
258 OldTypeRefs.FwdDecls.clear();
259
260 // Upgrade from old type ref arrays. In strange cases, this could add to
261 // OldTypeRefs.Unknown.
262 for (const auto &Array : OldTypeRefs.Arrays)
263 Array.second->replaceAllUsesWith(resolveTypeRefArray(Array.first.get()));
264 OldTypeRefs.Arrays.clear();
265
266 // Replace old string-based type refs with the resolved node, if possible.
267 // If we haven't seen the node, leave it to the verifier to complain about
268 // the invalid string reference.
269 for (const auto &Ref : OldTypeRefs.Unknown) {
270 if (DICompositeType *CT = OldTypeRefs.Final.lookup(Ref.first))
271 Ref.second->replaceAllUsesWith(CT);
272 else
273 Ref.second->replaceAllUsesWith(Ref.first);
274 }
275 OldTypeRefs.Unknown.clear();
276
277 if (UnresolvedNodes.empty())
278 // Nothing to do.
279 return;
280
281 // Resolve any cycles.
282 for (unsigned I : UnresolvedNodes) {
283 auto &MD = MetadataPtrs[I];
284 auto *N = dyn_cast_or_null<MDNode>(MD);
285 if (!N)
286 continue;
287
288 assert(!N->isTemporary() && "Unexpected forward reference")(static_cast <bool> (!N->isTemporary() && "Unexpected forward reference"
) ? void (0) : __assert_fail ("!N->isTemporary() && \"Unexpected forward reference\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 288, __extension__ __PRETTY_FUNCTION__))
;
289 N->resolveCycles();
290 }
291
292 // Make sure we return early again until there's another unresolved ref.
293 UnresolvedNodes.clear();
294}
295
296void BitcodeReaderMetadataList::addTypeRef(MDString &UUID,
297 DICompositeType &CT) {
298 assert(CT.getRawIdentifier() == &UUID && "Mismatched UUID")(static_cast <bool> (CT.getRawIdentifier() == &UUID
&& "Mismatched UUID") ? void (0) : __assert_fail ("CT.getRawIdentifier() == &UUID && \"Mismatched UUID\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 298, __extension__ __PRETTY_FUNCTION__))
;
299 if (CT.isForwardDecl())
300 OldTypeRefs.FwdDecls.insert(std::make_pair(&UUID, &CT));
301 else
302 OldTypeRefs.Final.insert(std::make_pair(&UUID, &CT));
303}
304
305Metadata *BitcodeReaderMetadataList::upgradeTypeRef(Metadata *MaybeUUID) {
306 auto *UUID = dyn_cast_or_null<MDString>(MaybeUUID);
307 if (LLVM_LIKELY(!UUID)__builtin_expect((bool)(!UUID), true))
308 return MaybeUUID;
309
310 if (auto *CT = OldTypeRefs.Final.lookup(UUID))
311 return CT;
312
313 auto &Ref = OldTypeRefs.Unknown[UUID];
314 if (!Ref)
315 Ref = MDNode::getTemporary(Context, None);
316 return Ref.get();
317}
318
319Metadata *BitcodeReaderMetadataList::upgradeTypeRefArray(Metadata *MaybeTuple) {
320 auto *Tuple = dyn_cast_or_null<MDTuple>(MaybeTuple);
321 if (!Tuple || Tuple->isDistinct())
322 return MaybeTuple;
323
324 // Look through the array immediately if possible.
325 if (!Tuple->isTemporary())
326 return resolveTypeRefArray(Tuple);
327
328 // Create and return a placeholder to use for now. Eventually
329 // resolveTypeRefArrays() will be resolve this forward reference.
330 OldTypeRefs.Arrays.emplace_back(
331 std::piecewise_construct, std::forward_as_tuple(Tuple),
332 std::forward_as_tuple(MDTuple::getTemporary(Context, None)));
333 return OldTypeRefs.Arrays.back().second.get();
334}
335
336Metadata *BitcodeReaderMetadataList::resolveTypeRefArray(Metadata *MaybeTuple) {
337 auto *Tuple = dyn_cast_or_null<MDTuple>(MaybeTuple);
338 if (!Tuple || Tuple->isDistinct())
339 return MaybeTuple;
340
341 // Look through the DITypeRefArray, upgrading each DITypeRef.
342 SmallVector<Metadata *, 32> Ops;
343 Ops.reserve(Tuple->getNumOperands());
344 for (Metadata *MD : Tuple->operands())
345 Ops.push_back(upgradeTypeRef(MD));
346
347 return MDTuple::get(Context, Ops);
348}
349
350namespace {
351
352class PlaceholderQueue {
353 // Placeholders would thrash around when moved, so store in a std::deque
354 // instead of some sort of vector.
355 std::deque<DistinctMDOperandPlaceholder> PHs;
356
357public:
358 ~PlaceholderQueue() {
359 assert(empty() && "PlaceholderQueue hasn't been flushed before being destroyed")(static_cast <bool> (empty() && "PlaceholderQueue hasn't been flushed before being destroyed"
) ? void (0) : __assert_fail ("empty() && \"PlaceholderQueue hasn't been flushed before being destroyed\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 359, __extension__ __PRETTY_FUNCTION__))
;
360 }
361 bool empty() { return PHs.empty(); }
362 DistinctMDOperandPlaceholder &getPlaceholderOp(unsigned ID);
363 void flush(BitcodeReaderMetadataList &MetadataList);
364
365 /// Return the list of temporaries nodes in the queue, these need to be
366 /// loaded before we can flush the queue.
367 void getTemporaries(BitcodeReaderMetadataList &MetadataList,
368 DenseSet<unsigned> &Temporaries) {
369 for (auto &PH : PHs) {
370 auto ID = PH.getID();
371 auto *MD = MetadataList.lookup(ID);
372 if (!MD) {
373 Temporaries.insert(ID);
374 continue;
375 }
376 auto *N = dyn_cast_or_null<MDNode>(MD);
377 if (N && N->isTemporary())
378 Temporaries.insert(ID);
379 }
380 }
381};
382
383} // end anonymous namespace
384
385DistinctMDOperandPlaceholder &PlaceholderQueue::getPlaceholderOp(unsigned ID) {
386 PHs.emplace_back(ID);
387 return PHs.back();
388}
389
390void PlaceholderQueue::flush(BitcodeReaderMetadataList &MetadataList) {
391 while (!PHs.empty()) {
392 auto *MD = MetadataList.lookup(PHs.front().getID());
393 assert(MD && "Flushing placeholder on unassigned MD")(static_cast <bool> (MD && "Flushing placeholder on unassigned MD"
) ? void (0) : __assert_fail ("MD && \"Flushing placeholder on unassigned MD\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 393, __extension__ __PRETTY_FUNCTION__))
;
394#ifndef NDEBUG
395 if (auto *MDN = dyn_cast<MDNode>(MD))
396 assert(MDN->isResolved() &&(static_cast <bool> (MDN->isResolved() && "Flushing Placeholder while cycles aren't resolved"
) ? void (0) : __assert_fail ("MDN->isResolved() && \"Flushing Placeholder while cycles aren't resolved\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 397, __extension__ __PRETTY_FUNCTION__))
397 "Flushing Placeholder while cycles aren't resolved")(static_cast <bool> (MDN->isResolved() && "Flushing Placeholder while cycles aren't resolved"
) ? void (0) : __assert_fail ("MDN->isResolved() && \"Flushing Placeholder while cycles aren't resolved\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 397, __extension__ __PRETTY_FUNCTION__))
;
398#endif
399 PHs.front().replaceUseWith(MD);
400 PHs.pop_front();
401 }
402}
403
404} // anonynous namespace
405
406static Error error(const Twine &Message) {
407 return make_error<StringError>(
408 Message, make_error_code(BitcodeError::CorruptedBitcode));
409}
410
411class MetadataLoader::MetadataLoaderImpl {
412 BitcodeReaderMetadataList MetadataList;
413 BitcodeReaderValueList &ValueList;
414 BitstreamCursor &Stream;
415 LLVMContext &Context;
416 Module &TheModule;
417 std::function<Type *(unsigned)> getTypeByID;
418
419 /// Cursor associated with the lazy-loading of Metadata. This is the easy way
420 /// to keep around the right "context" (Abbrev list) to be able to jump in
421 /// the middle of the metadata block and load any record.
422 BitstreamCursor IndexCursor;
423
424 /// Index that keeps track of MDString values.
425 std::vector<StringRef> MDStringRef;
426
427 /// On-demand loading of a single MDString. Requires the index above to be
428 /// populated.
429 MDString *lazyLoadOneMDString(unsigned Idx);
430
431 /// Index that keeps track of where to find a metadata record in the stream.
432 std::vector<uint64_t> GlobalMetadataBitPosIndex;
433
434 /// Populate the index above to enable lazily loading of metadata, and load
435 /// the named metadata as well as the transitively referenced global
436 /// Metadata.
437 Expected<bool> lazyLoadModuleMetadataBlock();
438
439 /// On-demand loading of a single metadata. Requires the index above to be
440 /// populated.
441 void lazyLoadOneMetadata(unsigned Idx, PlaceholderQueue &Placeholders);
442
443 // Keep mapping of seens pair of old-style CU <-> SP, and update pointers to
444 // point from SP to CU after a block is completly parsed.
445 std::vector<std::pair<DICompileUnit *, Metadata *>> CUSubprograms;
446
447 /// Functions that need to be matched with subprograms when upgrading old
448 /// metadata.
449 SmallDenseMap<Function *, DISubprogram *, 16> FunctionsWithSPs;
450
451 // Map the bitcode's custom MDKind ID to the Module's MDKind ID.
452 DenseMap<unsigned, unsigned> MDKindMap;
453
454 bool StripTBAA = false;
455 bool HasSeenOldLoopTags = false;
456 bool NeedUpgradeToDIGlobalVariableExpression = false;
457 bool NeedDeclareExpressionUpgrade = false;
458
459 /// True if metadata is being parsed for a module being ThinLTO imported.
460 bool IsImporting = false;
461
462 Error parseOneMetadata(SmallVectorImpl<uint64_t> &Record, unsigned Code,
463 PlaceholderQueue &Placeholders, StringRef Blob,
464 unsigned &NextMetadataNo);
465 Error parseMetadataStrings(ArrayRef<uint64_t> Record, StringRef Blob,
466 function_ref<void(StringRef)> CallBack);
467 Error parseGlobalObjectAttachment(GlobalObject &GO,
468 ArrayRef<uint64_t> Record);
469 Error parseMetadataKindRecord(SmallVectorImpl<uint64_t> &Record);
470
471 void resolveForwardRefsAndPlaceholders(PlaceholderQueue &Placeholders);
472
473 /// Upgrade old-style CU <-> SP pointers to point from SP to CU.
474 void upgradeCUSubprograms() {
475 for (auto CU_SP : CUSubprograms)
476 if (auto *SPs = dyn_cast_or_null<MDTuple>(CU_SP.second))
477 for (auto &Op : SPs->operands())
478 if (auto *SP = dyn_cast_or_null<DISubprogram>(Op))
479 SP->replaceUnit(CU_SP.first);
480 CUSubprograms.clear();
481 }
482
483 /// Upgrade old-style bare DIGlobalVariables to DIGlobalVariableExpressions.
484 void upgradeCUVariables() {
485 if (!NeedUpgradeToDIGlobalVariableExpression)
486 return;
487
488 // Upgrade list of variables attached to the CUs.
489 if (NamedMDNode *CUNodes = TheModule.getNamedMetadata("llvm.dbg.cu"))
490 for (unsigned I = 0, E = CUNodes->getNumOperands(); I != E; ++I) {
491 auto *CU = cast<DICompileUnit>(CUNodes->getOperand(I));
492 if (auto *GVs = dyn_cast_or_null<MDTuple>(CU->getRawGlobalVariables()))
493 for (unsigned I = 0; I < GVs->getNumOperands(); I++)
494 if (auto *GV =
495 dyn_cast_or_null<DIGlobalVariable>(GVs->getOperand(I))) {
496 auto *DGVE = DIGlobalVariableExpression::getDistinct(
497 Context, GV, DIExpression::get(Context, {}));
498 GVs->replaceOperandWith(I, DGVE);
499 }
500 }
501
502 // Upgrade variables attached to globals.
503 for (auto &GV : TheModule.globals()) {
504 SmallVector<MDNode *, 1> MDs;
505 GV.getMetadata(LLVMContext::MD_dbg, MDs);
506 GV.eraseMetadata(LLVMContext::MD_dbg);
507 for (auto *MD : MDs)
508 if (auto *DGV = dyn_cast_or_null<DIGlobalVariable>(MD)) {
509 auto *DGVE = DIGlobalVariableExpression::getDistinct(
510 Context, DGV, DIExpression::get(Context, {}));
511 GV.addMetadata(LLVMContext::MD_dbg, *DGVE);
512 } else
513 GV.addMetadata(LLVMContext::MD_dbg, *MD);
514 }
515 }
516
517 /// Remove a leading DW_OP_deref from DIExpressions in a dbg.declare that
518 /// describes a function argument.
519 void upgradeDeclareExpressions(Function &F) {
520 if (!NeedDeclareExpressionUpgrade)
521 return;
522
523 for (auto &BB : F)
524 for (auto &I : BB)
525 if (auto *DDI = dyn_cast<DbgDeclareInst>(&I))
526 if (auto *DIExpr = DDI->getExpression())
527 if (DIExpr->startsWithDeref() &&
528 dyn_cast_or_null<Argument>(DDI->getAddress())) {
529 SmallVector<uint64_t, 8> Ops;
530 Ops.append(std::next(DIExpr->elements_begin()),
531 DIExpr->elements_end());
532 auto *E = DIExpression::get(Context, Ops);
533 DDI->setOperand(2, MetadataAsValue::get(Context, E));
534 }
535 }
536
537 /// Upgrade the expression from previous versions.
538 Error upgradeDIExpression(uint64_t FromVersion,
539 MutableArrayRef<uint64_t> &Expr,
540 SmallVectorImpl<uint64_t> &Buffer) {
541 auto N = Expr.size();
542 switch (FromVersion) {
543 default:
544 return error("Invalid record");
545 case 0:
546 if (N >= 3 && Expr[N - 3] == dwarf::DW_OP_bit_piece)
547 Expr[N - 3] = dwarf::DW_OP_LLVM_fragment;
548 LLVM_FALLTHROUGH[[clang::fallthrough]];
549 case 1:
550 // Move DW_OP_deref to the end.
551 if (N && Expr[0] == dwarf::DW_OP_deref) {
552 auto End = Expr.end();
553 if (Expr.size() >= 3 &&
554 *std::prev(End, 3) == dwarf::DW_OP_LLVM_fragment)
555 End = std::prev(End, 3);
556 std::move(std::next(Expr.begin()), End, Expr.begin());
557 *std::prev(End) = dwarf::DW_OP_deref;
558 }
559 NeedDeclareExpressionUpgrade = true;
560 LLVM_FALLTHROUGH[[clang::fallthrough]];
561 case 2: {
562 // Change DW_OP_plus to DW_OP_plus_uconst.
563 // Change DW_OP_minus to DW_OP_uconst, DW_OP_minus
564 auto SubExpr = ArrayRef<uint64_t>(Expr);
565 while (!SubExpr.empty()) {
566 // Skip past other operators with their operands
567 // for this version of the IR, obtained from
568 // from historic DIExpression::ExprOperand::getSize().
569 size_t HistoricSize;
570 switch (SubExpr.front()) {
571 default:
572 HistoricSize = 1;
573 break;
574 case dwarf::DW_OP_constu:
575 case dwarf::DW_OP_minus:
576 case dwarf::DW_OP_plus:
577 HistoricSize = 2;
578 break;
579 case dwarf::DW_OP_LLVM_fragment:
580 HistoricSize = 3;
581 break;
582 }
583
584 // If the expression is malformed, make sure we don't
585 // copy more elements than we should.
586 HistoricSize = std::min(SubExpr.size(), HistoricSize);
587 ArrayRef<uint64_t> Args = SubExpr.slice(1, HistoricSize-1);
588
589 switch (SubExpr.front()) {
590 case dwarf::DW_OP_plus:
591 Buffer.push_back(dwarf::DW_OP_plus_uconst);
592 Buffer.append(Args.begin(), Args.end());
593 break;
594 case dwarf::DW_OP_minus:
595 Buffer.push_back(dwarf::DW_OP_constu);
596 Buffer.append(Args.begin(), Args.end());
597 Buffer.push_back(dwarf::DW_OP_minus);
598 break;
599 default:
600 Buffer.push_back(*SubExpr.begin());
601 Buffer.append(Args.begin(), Args.end());
602 break;
603 }
604
605 // Continue with remaining elements.
606 SubExpr = SubExpr.slice(HistoricSize);
607 }
608 Expr = MutableArrayRef<uint64_t>(Buffer);
609 LLVM_FALLTHROUGH[[clang::fallthrough]];
610 }
611 case 3:
612 // Up-to-date!
613 break;
614 }
615
616 return Error::success();
617 }
618
619 void upgradeDebugInfo() {
620 upgradeCUSubprograms();
621 upgradeCUVariables();
622 }
623
624public:
625 MetadataLoaderImpl(BitstreamCursor &Stream, Module &TheModule,
626 BitcodeReaderValueList &ValueList,
627 std::function<Type *(unsigned)> getTypeByID,
628 bool IsImporting)
629 : MetadataList(TheModule.getContext()), ValueList(ValueList),
630 Stream(Stream), Context(TheModule.getContext()), TheModule(TheModule),
631 getTypeByID(std::move(getTypeByID)), IsImporting(IsImporting) {}
632
633 Error parseMetadata(bool ModuleLevel);
634
635 bool hasFwdRefs() const { return MetadataList.hasFwdRefs(); }
636
637 Metadata *getMetadataFwdRefOrLoad(unsigned ID) {
638 if (ID < MDStringRef.size())
639 return lazyLoadOneMDString(ID);
640 if (auto *MD = MetadataList.lookup(ID))
641 return MD;
642 // If lazy-loading is enabled, we try recursively to load the operand
643 // instead of creating a temporary.
644 if (ID < (MDStringRef.size() + GlobalMetadataBitPosIndex.size())) {
645 PlaceholderQueue Placeholders;
646 lazyLoadOneMetadata(ID, Placeholders);
647 resolveForwardRefsAndPlaceholders(Placeholders);
648 return MetadataList.lookup(ID);
649 }
650 return MetadataList.getMetadataFwdRef(ID);
651 }
652
653 MDNode *getMDNodeFwdRefOrNull(unsigned Idx) {
654 return MetadataList.getMDNodeFwdRefOrNull(Idx);
655 }
656
657 DISubprogram *lookupSubprogramForFunction(Function *F) {
658 return FunctionsWithSPs.lookup(F);
659 }
660
661 bool hasSeenOldLoopTags() { return HasSeenOldLoopTags; }
662
663 Error parseMetadataAttachment(
664 Function &F, const SmallVectorImpl<Instruction *> &InstructionList);
665
666 Error parseMetadataKinds();
667
668 void setStripTBAA(bool Value) { StripTBAA = Value; }
669 bool isStrippingTBAA() { return StripTBAA; }
670
671 unsigned size() const { return MetadataList.size(); }
672 void shrinkTo(unsigned N) { MetadataList.shrinkTo(N); }
673 void upgradeDebugIntrinsics(Function &F) { upgradeDeclareExpressions(F); }
674};
675
676Expected<bool>
677MetadataLoader::MetadataLoaderImpl::lazyLoadModuleMetadataBlock() {
678 IndexCursor = Stream;
679 SmallVector<uint64_t, 64> Record;
680 // Get the abbrevs, and preload record positions to make them lazy-loadable.
681 while (true) {
682 BitstreamEntry Entry = IndexCursor.advanceSkippingSubblocks(
683 BitstreamCursor::AF_DontPopBlockAtEnd);
684 switch (Entry.Kind) {
685 case BitstreamEntry::SubBlock: // Handled for us already.
686 case BitstreamEntry::Error:
687 return error("Malformed block");
688 case BitstreamEntry::EndBlock: {
689 return true;
690 }
691 case BitstreamEntry::Record: {
692 // The interesting case.
693 ++NumMDRecordLoaded;
694 uint64_t CurrentPos = IndexCursor.GetCurrentBitNo();
695 auto Code = IndexCursor.skipRecord(Entry.ID);
696 switch (Code) {
697 case bitc::METADATA_STRINGS: {
698 // Rewind and parse the strings.
699 IndexCursor.JumpToBit(CurrentPos);
700 StringRef Blob;
701 Record.clear();
702 IndexCursor.readRecord(Entry.ID, Record, &Blob);
703 unsigned NumStrings = Record[0];
704 MDStringRef.reserve(NumStrings);
705 auto IndexNextMDString = [&](StringRef Str) {
706 MDStringRef.push_back(Str);
707 };
708 if (auto Err = parseMetadataStrings(Record, Blob, IndexNextMDString))
709 return std::move(Err);
710 break;
711 }
712 case bitc::METADATA_INDEX_OFFSET: {
713 // This is the offset to the index, when we see this we skip all the
714 // records and load only an index to these.
715 IndexCursor.JumpToBit(CurrentPos);
716 Record.clear();
717 IndexCursor.readRecord(Entry.ID, Record);
718 if (Record.size() != 2)
719 return error("Invalid record");
720 auto Offset = Record[0] + (Record[1] << 32);
721 auto BeginPos = IndexCursor.GetCurrentBitNo();
722 IndexCursor.JumpToBit(BeginPos + Offset);
723 Entry = IndexCursor.advanceSkippingSubblocks(
724 BitstreamCursor::AF_DontPopBlockAtEnd);
725 assert(Entry.Kind == BitstreamEntry::Record &&(static_cast <bool> (Entry.Kind == BitstreamEntry::Record
&& "Corrupted bitcode: Expected `Record` when trying to find the "
"Metadata index") ? void (0) : __assert_fail ("Entry.Kind == BitstreamEntry::Record && \"Corrupted bitcode: Expected `Record` when trying to find the \" \"Metadata index\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 727, __extension__ __PRETTY_FUNCTION__))
726 "Corrupted bitcode: Expected `Record` when trying to find the "(static_cast <bool> (Entry.Kind == BitstreamEntry::Record
&& "Corrupted bitcode: Expected `Record` when trying to find the "
"Metadata index") ? void (0) : __assert_fail ("Entry.Kind == BitstreamEntry::Record && \"Corrupted bitcode: Expected `Record` when trying to find the \" \"Metadata index\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 727, __extension__ __PRETTY_FUNCTION__))
727 "Metadata index")(static_cast <bool> (Entry.Kind == BitstreamEntry::Record
&& "Corrupted bitcode: Expected `Record` when trying to find the "
"Metadata index") ? void (0) : __assert_fail ("Entry.Kind == BitstreamEntry::Record && \"Corrupted bitcode: Expected `Record` when trying to find the \" \"Metadata index\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 727, __extension__ __PRETTY_FUNCTION__))
;
728 Record.clear();
729 auto Code = IndexCursor.readRecord(Entry.ID, Record);
730 (void)Code;
731 assert(Code == bitc::METADATA_INDEX && "Corrupted bitcode: Expected "(static_cast <bool> (Code == bitc::METADATA_INDEX &&
"Corrupted bitcode: Expected " "`METADATA_INDEX` when trying "
"to find the Metadata index") ? void (0) : __assert_fail ("Code == bitc::METADATA_INDEX && \"Corrupted bitcode: Expected \" \"`METADATA_INDEX` when trying \" \"to find the Metadata index\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 733, __extension__ __PRETTY_FUNCTION__))
732 "`METADATA_INDEX` when trying "(static_cast <bool> (Code == bitc::METADATA_INDEX &&
"Corrupted bitcode: Expected " "`METADATA_INDEX` when trying "
"to find the Metadata index") ? void (0) : __assert_fail ("Code == bitc::METADATA_INDEX && \"Corrupted bitcode: Expected \" \"`METADATA_INDEX` when trying \" \"to find the Metadata index\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 733, __extension__ __PRETTY_FUNCTION__))
733 "to find the Metadata index")(static_cast <bool> (Code == bitc::METADATA_INDEX &&
"Corrupted bitcode: Expected " "`METADATA_INDEX` when trying "
"to find the Metadata index") ? void (0) : __assert_fail ("Code == bitc::METADATA_INDEX && \"Corrupted bitcode: Expected \" \"`METADATA_INDEX` when trying \" \"to find the Metadata index\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 733, __extension__ __PRETTY_FUNCTION__))
;
734
735 // Delta unpack
736 auto CurrentValue = BeginPos;
737 GlobalMetadataBitPosIndex.reserve(Record.size());
738 for (auto &Elt : Record) {
739 CurrentValue += Elt;
740 GlobalMetadataBitPosIndex.push_back(CurrentValue);
741 }
742 break;
743 }
744 case bitc::METADATA_INDEX:
745 // We don't expect to get there, the Index is loaded when we encounter
746 // the offset.
747 return error("Corrupted Metadata block");
748 case bitc::METADATA_NAME: {
749 // Named metadata need to be materialized now and aren't deferred.
750 IndexCursor.JumpToBit(CurrentPos);
751 Record.clear();
752 unsigned Code = IndexCursor.readRecord(Entry.ID, Record);
753 assert(Code == bitc::METADATA_NAME)(static_cast <bool> (Code == bitc::METADATA_NAME) ? void
(0) : __assert_fail ("Code == bitc::METADATA_NAME", "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 753, __extension__ __PRETTY_FUNCTION__))
;
754
755 // Read name of the named metadata.
756 SmallString<8> Name(Record.begin(), Record.end());
757 Code = IndexCursor.ReadCode();
758
759 // Named Metadata comes in two parts, we expect the name to be followed
760 // by the node
761 Record.clear();
762 unsigned NextBitCode = IndexCursor.readRecord(Code, Record);
763 assert(NextBitCode == bitc::METADATA_NAMED_NODE)(static_cast <bool> (NextBitCode == bitc::METADATA_NAMED_NODE
) ? void (0) : __assert_fail ("NextBitCode == bitc::METADATA_NAMED_NODE"
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 763, __extension__ __PRETTY_FUNCTION__))
;
764 (void)NextBitCode;
765
766 // Read named metadata elements.
767 unsigned Size = Record.size();
768 NamedMDNode *NMD = TheModule.getOrInsertNamedMetadata(Name);
769 for (unsigned i = 0; i != Size; ++i) {
770 // FIXME: We could use a placeholder here, however NamedMDNode are
771 // taking MDNode as operand and not using the Metadata infrastructure.
772 // It is acknowledged by 'TODO: Inherit from Metadata' in the
773 // NamedMDNode class definition.
774 MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[i]);
775 assert(MD && "Invalid record")(static_cast <bool> (MD && "Invalid record") ? void
(0) : __assert_fail ("MD && \"Invalid record\"", "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 775, __extension__ __PRETTY_FUNCTION__))
;
776 NMD->addOperand(MD);
777 }
778 break;
779 }
780 case bitc::METADATA_GLOBAL_DECL_ATTACHMENT: {
781 // FIXME: we need to do this early because we don't materialize global
782 // value explicitly.
783 IndexCursor.JumpToBit(CurrentPos);
784 Record.clear();
785 IndexCursor.readRecord(Entry.ID, Record);
786 if (Record.size() % 2 == 0)
787 return error("Invalid record");
788 unsigned ValueID = Record[0];
789 if (ValueID >= ValueList.size())
790 return error("Invalid record");
791 if (auto *GO = dyn_cast<GlobalObject>(ValueList[ValueID]))
792 if (Error Err = parseGlobalObjectAttachment(
793 *GO, ArrayRef<uint64_t>(Record).slice(1)))
794 return std::move(Err);
795 break;
796 }
797 case bitc::METADATA_KIND:
798 case bitc::METADATA_STRING_OLD:
799 case bitc::METADATA_OLD_FN_NODE:
800 case bitc::METADATA_OLD_NODE:
801 case bitc::METADATA_VALUE:
802 case bitc::METADATA_DISTINCT_NODE:
803 case bitc::METADATA_NODE:
804 case bitc::METADATA_LOCATION:
805 case bitc::METADATA_GENERIC_DEBUG:
806 case bitc::METADATA_SUBRANGE:
807 case bitc::METADATA_ENUMERATOR:
808 case bitc::METADATA_BASIC_TYPE:
809 case bitc::METADATA_DERIVED_TYPE:
810 case bitc::METADATA_COMPOSITE_TYPE:
811 case bitc::METADATA_SUBROUTINE_TYPE:
812 case bitc::METADATA_MODULE:
813 case bitc::METADATA_FILE:
814 case bitc::METADATA_COMPILE_UNIT:
815 case bitc::METADATA_SUBPROGRAM:
816 case bitc::METADATA_LEXICAL_BLOCK:
817 case bitc::METADATA_LEXICAL_BLOCK_FILE:
818 case bitc::METADATA_NAMESPACE:
819 case bitc::METADATA_MACRO:
820 case bitc::METADATA_MACRO_FILE:
821 case bitc::METADATA_TEMPLATE_TYPE:
822 case bitc::METADATA_TEMPLATE_VALUE:
823 case bitc::METADATA_GLOBAL_VAR:
824 case bitc::METADATA_LOCAL_VAR:
825 case bitc::METADATA_EXPRESSION:
826 case bitc::METADATA_OBJC_PROPERTY:
827 case bitc::METADATA_IMPORTED_ENTITY:
828 case bitc::METADATA_GLOBAL_VAR_EXPR:
829 // We don't expect to see any of these, if we see one, give up on
830 // lazy-loading and fallback.
831 MDStringRef.clear();
832 GlobalMetadataBitPosIndex.clear();
833 return false;
834 }
835 break;
836 }
837 }
838 }
839}
840
841/// Parse a METADATA_BLOCK. If ModuleLevel is true then we are parsing
842/// module level metadata.
843Error MetadataLoader::MetadataLoaderImpl::parseMetadata(bool ModuleLevel) {
844 if (!ModuleLevel && MetadataList.hasFwdRefs())
845 return error("Invalid metadata: fwd refs into function blocks");
846
847 // Record the entry position so that we can jump back here and efficiently
848 // skip the whole block in case we lazy-load.
849 auto EntryPos = Stream.GetCurrentBitNo();
850
851 if (Stream.EnterSubBlock(bitc::METADATA_BLOCK_ID))
852 return error("Invalid record");
853
854 SmallVector<uint64_t, 64> Record;
855 PlaceholderQueue Placeholders;
856
857 // We lazy-load module-level metadata: we build an index for each record, and
858 // then load individual record as needed, starting with the named metadata.
859 if (ModuleLevel && IsImporting && MetadataList.empty() &&
860 !DisableLazyLoading) {
861 auto SuccessOrErr = lazyLoadModuleMetadataBlock();
862 if (!SuccessOrErr)
863 return SuccessOrErr.takeError();
864 if (SuccessOrErr.get()) {
865 // An index was successfully created and we will be able to load metadata
866 // on-demand.
867 MetadataList.resize(MDStringRef.size() +
868 GlobalMetadataBitPosIndex.size());
869
870 // Reading the named metadata created forward references and/or
871 // placeholders, that we flush here.
872 resolveForwardRefsAndPlaceholders(Placeholders);
873 upgradeDebugInfo();
874 // Return at the beginning of the block, since it is easy to skip it
875 // entirely from there.
876 Stream.ReadBlockEnd(); // Pop the abbrev block context.
877 Stream.JumpToBit(EntryPos);
878 if (Stream.SkipBlock())
879 return error("Invalid record");
880 return Error::success();
881 }
882 // Couldn't load an index, fallback to loading all the block "old-style".
883 }
884
885 unsigned NextMetadataNo = MetadataList.size();
886
887 // Read all the records.
888 while (true) {
889 BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
890
891 switch (Entry.Kind) {
892 case BitstreamEntry::SubBlock: // Handled for us already.
893 case BitstreamEntry::Error:
894 return error("Malformed block");
895 case BitstreamEntry::EndBlock:
896 resolveForwardRefsAndPlaceholders(Placeholders);
897 upgradeDebugInfo();
898 return Error::success();
899 case BitstreamEntry::Record:
900 // The interesting case.
901 break;
902 }
903
904 // Read a record.
905 Record.clear();
906 StringRef Blob;
907 ++NumMDRecordLoaded;
908 unsigned Code = Stream.readRecord(Entry.ID, Record, &Blob);
909 if (Error Err =
910 parseOneMetadata(Record, Code, Placeholders, Blob, NextMetadataNo))
911 return Err;
912 }
913}
914
915MDString *MetadataLoader::MetadataLoaderImpl::lazyLoadOneMDString(unsigned ID) {
916 ++NumMDStringLoaded;
917 if (Metadata *MD = MetadataList.lookup(ID))
918 return cast<MDString>(MD);
919 auto MDS = MDString::get(Context, MDStringRef[ID]);
920 MetadataList.assignValue(MDS, ID);
921 return MDS;
922}
923
924void MetadataLoader::MetadataLoaderImpl::lazyLoadOneMetadata(
925 unsigned ID, PlaceholderQueue &Placeholders) {
926 assert(ID < (MDStringRef.size()) + GlobalMetadataBitPosIndex.size())(static_cast <bool> (ID < (MDStringRef.size()) + GlobalMetadataBitPosIndex
.size()) ? void (0) : __assert_fail ("ID < (MDStringRef.size()) + GlobalMetadataBitPosIndex.size()"
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 926, __extension__ __PRETTY_FUNCTION__))
;
927 assert(ID >= MDStringRef.size() && "Unexpected lazy-loading of MDString")(static_cast <bool> (ID >= MDStringRef.size() &&
"Unexpected lazy-loading of MDString") ? void (0) : __assert_fail
("ID >= MDStringRef.size() && \"Unexpected lazy-loading of MDString\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 927, __extension__ __PRETTY_FUNCTION__))
;
928 // Lookup first if the metadata hasn't already been loaded.
929 if (auto *MD = MetadataList.lookup(ID)) {
930 auto *N = dyn_cast_or_null<MDNode>(MD);
931 if (!N->isTemporary())
932 return;
933 }
934 SmallVector<uint64_t, 64> Record;
935 StringRef Blob;
936 IndexCursor.JumpToBit(GlobalMetadataBitPosIndex[ID - MDStringRef.size()]);
937 auto Entry = IndexCursor.advanceSkippingSubblocks();
938 ++NumMDRecordLoaded;
939 unsigned Code = IndexCursor.readRecord(Entry.ID, Record, &Blob);
940 if (Error Err = parseOneMetadata(Record, Code, Placeholders, Blob, ID))
941 report_fatal_error("Can't lazyload MD");
942}
943
944/// Ensure that all forward-references and placeholders are resolved.
945/// Iteratively lazy-loading metadata on-demand if needed.
946void MetadataLoader::MetadataLoaderImpl::resolveForwardRefsAndPlaceholders(
947 PlaceholderQueue &Placeholders) {
948 DenseSet<unsigned> Temporaries;
949 while (1) {
950 // Populate Temporaries with the placeholders that haven't been loaded yet.
951 Placeholders.getTemporaries(MetadataList, Temporaries);
952
953 // If we don't have any temporary, or FwdReference, we're done!
954 if (Temporaries.empty() && !MetadataList.hasFwdRefs())
955 break;
956
957 // First, load all the temporaries. This can add new placeholders or
958 // forward references.
959 for (auto ID : Temporaries)
960 lazyLoadOneMetadata(ID, Placeholders);
961 Temporaries.clear();
962
963 // Second, load the forward-references. This can also add new placeholders
964 // or forward references.
965 while (MetadataList.hasFwdRefs())
966 lazyLoadOneMetadata(MetadataList.getNextFwdRef(), Placeholders);
967 }
968 // At this point we don't have any forward reference remaining, or temporary
969 // that haven't been loaded. We can safely drop RAUW support and mark cycles
970 // as resolved.
971 MetadataList.tryToResolveCycles();
972
973 // Finally, everything is in place, we can replace the placeholders operands
974 // with the final node they refer to.
975 Placeholders.flush(MetadataList);
976}
977
978Error MetadataLoader::MetadataLoaderImpl::parseOneMetadata(
979 SmallVectorImpl<uint64_t> &Record, unsigned Code,
980 PlaceholderQueue &Placeholders, StringRef Blob, unsigned &NextMetadataNo) {
981
982 bool IsDistinct = false;
983 auto getMD = [&](unsigned ID) -> Metadata * {
984 if (ID < MDStringRef.size())
985 return lazyLoadOneMDString(ID);
986 if (!IsDistinct) {
987 if (auto *MD = MetadataList.lookup(ID))
988 return MD;
989 // If lazy-loading is enabled, we try recursively to load the operand
990 // instead of creating a temporary.
991 if (ID < (MDStringRef.size() + GlobalMetadataBitPosIndex.size())) {
992 // Create a temporary for the node that is referencing the operand we
993 // will lazy-load. It is needed before recursing in case there are
994 // uniquing cycles.
995 MetadataList.getMetadataFwdRef(NextMetadataNo);
996 lazyLoadOneMetadata(ID, Placeholders);
997 return MetadataList.lookup(ID);
998 }
999 // Return a temporary.
1000 return MetadataList.getMetadataFwdRef(ID);
1001 }
1002 if (auto *MD = MetadataList.getMetadataIfResolved(ID))
1003 return MD;
1004 return &Placeholders.getPlaceholderOp(ID);
1005 };
1006 auto getMDOrNull = [&](unsigned ID) -> Metadata * {
1007 if (ID)
1008 return getMD(ID - 1);
1009 return nullptr;
1010 };
1011 auto getMDOrNullWithoutPlaceholders = [&](unsigned ID) -> Metadata * {
1012 if (ID)
1013 return MetadataList.getMetadataFwdRef(ID - 1);
1014 return nullptr;
1015 };
1016 auto getMDString = [&](unsigned ID) -> MDString * {
1017 // This requires that the ID is not really a forward reference. In
1018 // particular, the MDString must already have been resolved.
1019 auto MDS = getMDOrNull(ID);
1020 return cast_or_null<MDString>(MDS);
1021 };
1022
1023 // Support for old type refs.
1024 auto getDITypeRefOrNull = [&](unsigned ID) {
1025 return MetadataList.upgradeTypeRef(getMDOrNull(ID));
1026 };
1027
1028#define GET_OR_DISTINCT(CLASS, ARGS) \
1029 (IsDistinct ? CLASS::getDistinct ARGS : CLASS::get ARGS)
1030
1031 switch (Code) {
1032 default: // Default behavior: ignore.
1033 break;
1034 case bitc::METADATA_NAME: {
1035 // Read name of the named metadata.
1036 SmallString<8> Name(Record.begin(), Record.end());
1037 Record.clear();
1038 Code = Stream.ReadCode();
1039
1040 ++NumMDRecordLoaded;
1041 unsigned NextBitCode = Stream.readRecord(Code, Record);
1042 if (NextBitCode != bitc::METADATA_NAMED_NODE)
1043 return error("METADATA_NAME not followed by METADATA_NAMED_NODE");
1044
1045 // Read named metadata elements.
1046 unsigned Size = Record.size();
1047 NamedMDNode *NMD = TheModule.getOrInsertNamedMetadata(Name);
1048 for (unsigned i = 0; i != Size; ++i) {
1049 MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[i]);
1050 if (!MD)
1051 return error("Invalid record");
1052 NMD->addOperand(MD);
1053 }
1054 break;
1055 }
1056 case bitc::METADATA_OLD_FN_NODE: {
1057 // FIXME: Remove in 4.0.
1058 // This is a LocalAsMetadata record, the only type of function-local
1059 // metadata.
1060 if (Record.size() % 2 == 1)
1061 return error("Invalid record");
1062
1063 // If this isn't a LocalAsMetadata record, we're dropping it. This used
1064 // to be legal, but there's no upgrade path.
1065 auto dropRecord = [&] {
1066 MetadataList.assignValue(MDNode::get(Context, None), NextMetadataNo);
1067 NextMetadataNo++;
1068 };
1069 if (Record.size() != 2) {
1070 dropRecord();
1071 break;
1072 }
1073
1074 Type *Ty = getTypeByID(Record[0]);
1075 if (Ty->isMetadataTy() || Ty->isVoidTy()) {
1076 dropRecord();
1077 break;
1078 }
1079
1080 MetadataList.assignValue(
1081 LocalAsMetadata::get(ValueList.getValueFwdRef(Record[1], Ty)),
1082 NextMetadataNo);
1083 NextMetadataNo++;
1084 break;
1085 }
1086 case bitc::METADATA_OLD_NODE: {
1087 // FIXME: Remove in 4.0.
1088 if (Record.size() % 2 == 1)
1089 return error("Invalid record");
1090
1091 unsigned Size = Record.size();
1092 SmallVector<Metadata *, 8> Elts;
1093 for (unsigned i = 0; i != Size; i += 2) {
1094 Type *Ty = getTypeByID(Record[i]);
1095 if (!Ty)
1096 return error("Invalid record");
1097 if (Ty->isMetadataTy())
1098 Elts.push_back(getMD(Record[i + 1]));
1099 else if (!Ty->isVoidTy()) {
1100 auto *MD =
1101 ValueAsMetadata::get(ValueList.getValueFwdRef(Record[i + 1], Ty));
1102 assert(isa<ConstantAsMetadata>(MD) &&(static_cast <bool> (isa<ConstantAsMetadata>(MD) &&
"Expected non-function-local metadata") ? void (0) : __assert_fail
("isa<ConstantAsMetadata>(MD) && \"Expected non-function-local metadata\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 1103, __extension__ __PRETTY_FUNCTION__))
1103 "Expected non-function-local metadata")(static_cast <bool> (isa<ConstantAsMetadata>(MD) &&
"Expected non-function-local metadata") ? void (0) : __assert_fail
("isa<ConstantAsMetadata>(MD) && \"Expected non-function-local metadata\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 1103, __extension__ __PRETTY_FUNCTION__))
;
1104 Elts.push_back(MD);
1105 } else
1106 Elts.push_back(nullptr);
1107 }
1108 MetadataList.assignValue(MDNode::get(Context, Elts), NextMetadataNo);
1109 NextMetadataNo++;
1110 break;
1111 }
1112 case bitc::METADATA_VALUE: {
1113 if (Record.size() != 2)
1114 return error("Invalid record");
1115
1116 Type *Ty = getTypeByID(Record[0]);
1117 if (Ty->isMetadataTy() || Ty->isVoidTy())
1118 return error("Invalid record");
1119
1120 MetadataList.assignValue(
1121 ValueAsMetadata::get(ValueList.getValueFwdRef(Record[1], Ty)),
1122 NextMetadataNo);
1123 NextMetadataNo++;
1124 break;
1125 }
1126 case bitc::METADATA_DISTINCT_NODE:
1127 IsDistinct = true;
1128 LLVM_FALLTHROUGH[[clang::fallthrough]];
1129 case bitc::METADATA_NODE: {
1130 SmallVector<Metadata *, 8> Elts;
1131 Elts.reserve(Record.size());
1132 for (unsigned ID : Record)
1133 Elts.push_back(getMDOrNull(ID));
1134 MetadataList.assignValue(IsDistinct ? MDNode::getDistinct(Context, Elts)
1135 : MDNode::get(Context, Elts),
1136 NextMetadataNo);
1137 NextMetadataNo++;
1138 break;
1139 }
1140 case bitc::METADATA_LOCATION: {
1141 if (Record.size() != 5)
1142 return error("Invalid record");
1143
1144 IsDistinct = Record[0];
1145 unsigned Line = Record[1];
1146 unsigned Column = Record[2];
1147 Metadata *Scope = getMD(Record[3]);
1148 Metadata *InlinedAt = getMDOrNull(Record[4]);
1149 MetadataList.assignValue(
1150 GET_OR_DISTINCT(DILocation, (Context, Line, Column, Scope, InlinedAt)),
1151 NextMetadataNo);
1152 NextMetadataNo++;
1153 break;
1154 }
1155 case bitc::METADATA_GENERIC_DEBUG: {
1156 if (Record.size() < 4)
1157 return error("Invalid record");
1158
1159 IsDistinct = Record[0];
1160 unsigned Tag = Record[1];
1161 unsigned Version = Record[2];
1162
1163 if (Tag >= 1u << 16 || Version != 0)
1164 return error("Invalid record");
1165
1166 auto *Header = getMDString(Record[3]);
1167 SmallVector<Metadata *, 8> DwarfOps;
1168 for (unsigned I = 4, E = Record.size(); I != E; ++I)
1169 DwarfOps.push_back(getMDOrNull(Record[I]));
1170 MetadataList.assignValue(
1171 GET_OR_DISTINCT(GenericDINode, (Context, Tag, Header, DwarfOps)),
1172 NextMetadataNo);
1173 NextMetadataNo++;
1174 break;
1175 }
1176 case bitc::METADATA_SUBRANGE: {
1177 Metadata *Val = nullptr;
1178 // Operand 'count' is interpreted as:
1179 // - Signed integer (version 0)
1180 // - Metadata node (version 1)
1181 switch (Record[0] >> 1) {
1182 case 0:
1183 Val = GET_OR_DISTINCT(DISubrange,
1184 (Context, Record[1], unrotateSign(Record.back())));
1185 break;
1186 case 1:
1187 Val = GET_OR_DISTINCT(DISubrange, (Context, getMDOrNull(Record[1]),
1188 unrotateSign(Record.back())));
1189 break;
1190 default:
1191 return error("Invalid record: Unsupported version of DISubrange");
1192 }
1193
1194 MetadataList.assignValue(Val, NextMetadataNo);
1195 IsDistinct = Record[0] & 1;
1196 NextMetadataNo++;
1197 break;
1198 }
1199 case bitc::METADATA_ENUMERATOR: {
1200 if (Record.size() != 3)
1201 return error("Invalid record");
1202
1203 IsDistinct = Record[0] & 1;
1204 bool IsUnsigned = Record[0] & 2;
1205 MetadataList.assignValue(
1206 GET_OR_DISTINCT(DIEnumerator, (Context, unrotateSign(Record[1]),
1207 IsUnsigned, getMDString(Record[2]))),
1208 NextMetadataNo);
1209 NextMetadataNo++;
1210 break;
1211 }
1212 case bitc::METADATA_BASIC_TYPE: {
1213 if (Record.size() != 6)
1214 return error("Invalid record");
1215
1216 IsDistinct = Record[0];
1217 MetadataList.assignValue(
1218 GET_OR_DISTINCT(DIBasicType,
1219 (Context, Record[1], getMDString(Record[2]), Record[3],
1220 Record[4], Record[5])),
1221 NextMetadataNo);
1222 NextMetadataNo++;
1223 break;
1224 }
1225 case bitc::METADATA_DERIVED_TYPE: {
1226 if (Record.size() < 12 || Record.size() > 13)
1227 return error("Invalid record");
1228
1229 // DWARF address space is encoded as N->getDWARFAddressSpace() + 1. 0 means
1230 // that there is no DWARF address space associated with DIDerivedType.
1231 Optional<unsigned> DWARFAddressSpace;
1232 if (Record.size() > 12 && Record[12])
1233 DWARFAddressSpace = Record[12] - 1;
1234
1235 IsDistinct = Record[0];
1236 DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[10]);
1237 MetadataList.assignValue(
1238 GET_OR_DISTINCT(DIDerivedType,
1239 (Context, Record[1], getMDString(Record[2]),
1240 getMDOrNull(Record[3]), Record[4],
1241 getDITypeRefOrNull(Record[5]),
1242 getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1243 Record[9], DWARFAddressSpace, Flags,
1244 getDITypeRefOrNull(Record[11]))),
1245 NextMetadataNo);
1246 NextMetadataNo++;
1247 break;
1248 }
1249 case bitc::METADATA_COMPOSITE_TYPE: {
1250 if (Record.size() < 16 || Record.size() > 17)
1251 return error("Invalid record");
1252
1253 // If we have a UUID and this is not a forward declaration, lookup the
1254 // mapping.
1255 IsDistinct = Record[0] & 0x1;
1256 bool IsNotUsedInTypeRef = Record[0] >= 2;
1257 unsigned Tag = Record[1];
1258 MDString *Name = getMDString(Record[2]);
1259 Metadata *File = getMDOrNull(Record[3]);
1260 unsigned Line = Record[4];
1261 Metadata *Scope = getDITypeRefOrNull(Record[5]);
1262 Metadata *BaseType = nullptr;
1263 uint64_t SizeInBits = Record[7];
1264 if (Record[8] > (uint64_t)std::numeric_limits<uint32_t>::max())
1265 return error("Alignment value is too large");
1266 uint32_t AlignInBits = Record[8];
1267 uint64_t OffsetInBits = 0;
1268 DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[10]);
1269 Metadata *Elements = nullptr;
1270 unsigned RuntimeLang = Record[12];
1271 Metadata *VTableHolder = nullptr;
1272 Metadata *TemplateParams = nullptr;
1273 Metadata *Discriminator = nullptr;
1274 auto *Identifier = getMDString(Record[15]);
1275 // If this module is being parsed so that it can be ThinLTO imported
1276 // into another module, composite types only need to be imported
1277 // as type declarations (unless full type definitions requested).
1278 // Create type declarations up front to save memory. Also, buildODRType
1279 // handles the case where this is type ODRed with a definition needed
1280 // by the importing module, in which case the existing definition is
1281 // used.
1282 if (IsImporting && !ImportFullTypeDefinitions && Identifier &&
1283 (Tag == dwarf::DW_TAG_enumeration_type ||
1284 Tag == dwarf::DW_TAG_class_type ||
1285 Tag == dwarf::DW_TAG_structure_type ||
1286 Tag == dwarf::DW_TAG_union_type)) {
1287 Flags = Flags | DINode::FlagFwdDecl;
1288 } else {
1289 BaseType = getDITypeRefOrNull(Record[6]);
1290 OffsetInBits = Record[9];
1291 Elements = getMDOrNull(Record[11]);
1292 VTableHolder = getDITypeRefOrNull(Record[13]);
1293 TemplateParams = getMDOrNull(Record[14]);
1294 if (Record.size() > 16)
1295 Discriminator = getMDOrNull(Record[16]);
1296 }
1297 DICompositeType *CT = nullptr;
1298 if (Identifier)
1299 CT = DICompositeType::buildODRType(
1300 Context, *Identifier, Tag, Name, File, Line, Scope, BaseType,
1301 SizeInBits, AlignInBits, OffsetInBits, Flags, Elements, RuntimeLang,
1302 VTableHolder, TemplateParams, Discriminator);
1303
1304 // Create a node if we didn't get a lazy ODR type.
1305 if (!CT)
1306 CT = GET_OR_DISTINCT(DICompositeType,
1307 (Context, Tag, Name, File, Line, Scope, BaseType,
1308 SizeInBits, AlignInBits, OffsetInBits, Flags,
1309 Elements, RuntimeLang, VTableHolder, TemplateParams,
1310 Identifier));
1311 if (!IsNotUsedInTypeRef && Identifier)
1312 MetadataList.addTypeRef(*Identifier, *cast<DICompositeType>(CT));
1313
1314 MetadataList.assignValue(CT, NextMetadataNo);
1315 NextMetadataNo++;
1316 break;
1317 }
1318 case bitc::METADATA_SUBROUTINE_TYPE: {
1319 if (Record.size() < 3 || Record.size() > 4)
1320 return error("Invalid record");
1321 bool IsOldTypeRefArray = Record[0] < 2;
1322 unsigned CC = (Record.size() > 3) ? Record[3] : 0;
1323
1324 IsDistinct = Record[0] & 0x1;
1325 DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[1]);
1326 Metadata *Types = getMDOrNull(Record[2]);
1327 if (LLVM_UNLIKELY(IsOldTypeRefArray)__builtin_expect((bool)(IsOldTypeRefArray), false))
1328 Types = MetadataList.upgradeTypeRefArray(Types);
1329
1330 MetadataList.assignValue(
1331 GET_OR_DISTINCT(DISubroutineType, (Context, Flags, CC, Types)),
1332 NextMetadataNo);
1333 NextMetadataNo++;
1334 break;
1335 }
1336
1337 case bitc::METADATA_MODULE: {
1338 if (Record.size() != 6)
1339 return error("Invalid record");
1340
1341 IsDistinct = Record[0];
1342 MetadataList.assignValue(
1343 GET_OR_DISTINCT(DIModule,
1344 (Context, getMDOrNull(Record[1]),
1345 getMDString(Record[2]), getMDString(Record[3]),
1346 getMDString(Record[4]), getMDString(Record[5]))),
1347 NextMetadataNo);
1348 NextMetadataNo++;
1349 break;
1350 }
1351
1352 case bitc::METADATA_FILE: {
1353 if (Record.size() != 3 && Record.size() != 5)
1354 return error("Invalid record");
1355
1356 IsDistinct = Record[0];
1357 Optional<DIFile::ChecksumInfo<MDString *>> Checksum;
1358 // The BitcodeWriter writes null bytes into Record[3:4] when the Checksum
1359 // is not present. This matches up with the old internal representation,
1360 // and the old encoding for CSK_None in the ChecksumKind. The new
1361 // representation reserves the value 0 in the ChecksumKind to continue to
1362 // encode None in a backwards-compatible way.
1363 if (Record.size() == 5 && Record[3] && Record[4])
1364 Checksum.emplace(static_cast<DIFile::ChecksumKind>(Record[3]),
1365 getMDString(Record[4]));
1366 MetadataList.assignValue(
1367 GET_OR_DISTINCT(
1368 DIFile,
1369 (Context, getMDString(Record[1]), getMDString(Record[2]),
1370 Checksum)),
1371 NextMetadataNo);
1372 NextMetadataNo++;
1373 break;
1374 }
1375 case bitc::METADATA_COMPILE_UNIT: {
1376 if (Record.size() < 14 || Record.size() > 19)
1377 return error("Invalid record");
1378
1379 // Ignore Record[0], which indicates whether this compile unit is
1380 // distinct. It's always distinct.
1381 IsDistinct = true;
1382 auto *CU = DICompileUnit::getDistinct(
1383 Context, Record[1], getMDOrNull(Record[2]), getMDString(Record[3]),
1384 Record[4], getMDString(Record[5]), Record[6], getMDString(Record[7]),
1385 Record[8], getMDOrNull(Record[9]), getMDOrNull(Record[10]),
1386 getMDOrNull(Record[12]), getMDOrNull(Record[13]),
1387 Record.size() <= 15 ? nullptr : getMDOrNull(Record[15]),
1388 Record.size() <= 14 ? 0 : Record[14],
1389 Record.size() <= 16 ? true : Record[16],
1390 Record.size() <= 17 ? false : Record[17],
1391 Record.size() <= 18 ? false : Record[18]);
1392
1393 MetadataList.assignValue(CU, NextMetadataNo);
1394 NextMetadataNo++;
1395
1396 // Move the Upgrade the list of subprograms.
1397 if (Metadata *SPs = getMDOrNullWithoutPlaceholders(Record[11]))
1398 CUSubprograms.push_back({CU, SPs});
1399 break;
1400 }
1401 case bitc::METADATA_SUBPROGRAM: {
1402 if (Record.size() < 18 || Record.size() > 21)
1403 return error("Invalid record");
1404
1405 IsDistinct =
1406 (Record[0] & 1) || Record[8]; // All definitions should be distinct.
1407 // Version 1 has a Function as Record[15].
1408 // Version 2 has removed Record[15].
1409 // Version 3 has the Unit as Record[15].
1410 // Version 4 added thisAdjustment.
1411 bool HasUnit = Record[0] >= 2;
1412 if (HasUnit && Record.size() < 19)
1413 return error("Invalid record");
1414 Metadata *CUorFn = getMDOrNull(Record[15]);
1415 unsigned Offset = Record.size() >= 19 ? 1 : 0;
1416 bool HasFn = Offset && !HasUnit;
1417 bool HasThisAdj = Record.size() >= 20;
1418 bool HasThrownTypes = Record.size() >= 21;
1419 DISubprogram *SP = GET_OR_DISTINCT(
1420 DISubprogram,
1421 (Context,
1422 getDITypeRefOrNull(Record[1]), // scope
1423 getMDString(Record[2]), // name
1424 getMDString(Record[3]), // linkageName
1425 getMDOrNull(Record[4]), // file
1426 Record[5], // line
1427 getMDOrNull(Record[6]), // type
1428 Record[7], // isLocal
1429 Record[8], // isDefinition
1430 Record[9], // scopeLine
1431 getDITypeRefOrNull(Record[10]), // containingType
1432 Record[11], // virtuality
1433 Record[12], // virtualIndex
1434 HasThisAdj ? Record[19] : 0, // thisAdjustment
1435 static_cast<DINode::DIFlags>(Record[13]), // flags
1436 Record[14], // isOptimized
1437 HasUnit ? CUorFn : nullptr, // unit
1438 getMDOrNull(Record[15 + Offset]), // templateParams
1439 getMDOrNull(Record[16 + Offset]), // declaration
1440 getMDOrNull(Record[17 + Offset]), // variables
1441 HasThrownTypes ? getMDOrNull(Record[20]) : nullptr // thrownTypes
1442 ));
1443 MetadataList.assignValue(SP, NextMetadataNo);
1444 NextMetadataNo++;
1445
1446 // Upgrade sp->function mapping to function->sp mapping.
1447 if (HasFn) {
1448 if (auto *CMD = dyn_cast_or_null<ConstantAsMetadata>(CUorFn))
1449 if (auto *F = dyn_cast<Function>(CMD->getValue())) {
1450 if (F->isMaterializable())
1451 // Defer until materialized; unmaterialized functions may not have
1452 // metadata.
1453 FunctionsWithSPs[F] = SP;
1454 else if (!F->empty())
1455 F->setSubprogram(SP);
1456 }
1457 }
1458 break;
1459 }
1460 case bitc::METADATA_LEXICAL_BLOCK: {
1461 if (Record.size() != 5)
1462 return error("Invalid record");
1463
1464 IsDistinct = Record[0];
1465 MetadataList.assignValue(
1466 GET_OR_DISTINCT(DILexicalBlock,
1467 (Context, getMDOrNull(Record[1]),
1468 getMDOrNull(Record[2]), Record[3], Record[4])),
1469 NextMetadataNo);
1470 NextMetadataNo++;
1471 break;
1472 }
1473 case bitc::METADATA_LEXICAL_BLOCK_FILE: {
1474 if (Record.size() != 4)
1475 return error("Invalid record");
1476
1477 IsDistinct = Record[0];
1478 MetadataList.assignValue(
1479 GET_OR_DISTINCT(DILexicalBlockFile,
1480 (Context, getMDOrNull(Record[1]),
1481 getMDOrNull(Record[2]), Record[3])),
1482 NextMetadataNo);
1483 NextMetadataNo++;
1484 break;
1485 }
1486 case bitc::METADATA_NAMESPACE: {
1487 // Newer versions of DINamespace dropped file and line.
1488 MDString *Name;
1489 if (Record.size() == 3)
1490 Name = getMDString(Record[2]);
1491 else if (Record.size() == 5)
1492 Name = getMDString(Record[3]);
1493 else
1494 return error("Invalid record");
1495
1496 IsDistinct = Record[0] & 1;
1497 bool ExportSymbols = Record[0] & 2;
1498 MetadataList.assignValue(
1499 GET_OR_DISTINCT(DINamespace,
1500 (Context, getMDOrNull(Record[1]), Name, ExportSymbols)),
1501 NextMetadataNo);
1502 NextMetadataNo++;
1503 break;
1504 }
1505 case bitc::METADATA_MACRO: {
1506 if (Record.size() != 5)
1507 return error("Invalid record");
1508
1509 IsDistinct = Record[0];
1510 MetadataList.assignValue(
1511 GET_OR_DISTINCT(DIMacro,
1512 (Context, Record[1], Record[2], getMDString(Record[3]),
1513 getMDString(Record[4]))),
1514 NextMetadataNo);
1515 NextMetadataNo++;
1516 break;
1517 }
1518 case bitc::METADATA_MACRO_FILE: {
1519 if (Record.size() != 5)
1520 return error("Invalid record");
1521
1522 IsDistinct = Record[0];
1523 MetadataList.assignValue(
1524 GET_OR_DISTINCT(DIMacroFile,
1525 (Context, Record[1], Record[2], getMDOrNull(Record[3]),
1526 getMDOrNull(Record[4]))),
1527 NextMetadataNo);
1528 NextMetadataNo++;
1529 break;
1530 }
1531 case bitc::METADATA_TEMPLATE_TYPE: {
1532 if (Record.size() != 3)
1533 return error("Invalid record");
1534
1535 IsDistinct = Record[0];
1536 MetadataList.assignValue(GET_OR_DISTINCT(DITemplateTypeParameter,
1537 (Context, getMDString(Record[1]),
1538 getDITypeRefOrNull(Record[2]))),
1539 NextMetadataNo);
1540 NextMetadataNo++;
1541 break;
1542 }
1543 case bitc::METADATA_TEMPLATE_VALUE: {
1544 if (Record.size() != 5)
1545 return error("Invalid record");
1546
1547 IsDistinct = Record[0];
1548 MetadataList.assignValue(
1549 GET_OR_DISTINCT(DITemplateValueParameter,
1550 (Context, Record[1], getMDString(Record[2]),
1551 getDITypeRefOrNull(Record[3]),
1552 getMDOrNull(Record[4]))),
1553 NextMetadataNo);
1554 NextMetadataNo++;
1555 break;
1556 }
1557 case bitc::METADATA_GLOBAL_VAR: {
1558 if (Record.size() < 11 || Record.size() > 12)
1559 return error("Invalid record");
1560
1561 IsDistinct = Record[0] & 1;
1562 unsigned Version = Record[0] >> 1;
1563
1564 if (Version == 1) {
1565 MetadataList.assignValue(
1566 GET_OR_DISTINCT(DIGlobalVariable,
1567 (Context, getMDOrNull(Record[1]),
1568 getMDString(Record[2]), getMDString(Record[3]),
1569 getMDOrNull(Record[4]), Record[5],
1570 getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1571 getMDOrNull(Record[10]), Record[11])),
1572 NextMetadataNo);
1573 NextMetadataNo++;
1574 } else if (Version == 0) {
1575 // Upgrade old metadata, which stored a global variable reference or a
1576 // ConstantInt here.
1577 NeedUpgradeToDIGlobalVariableExpression = true;
1578 Metadata *Expr = getMDOrNull(Record[9]);
1579 uint32_t AlignInBits = 0;
1580 if (Record.size() > 11) {
1581 if (Record[11] > (uint64_t)std::numeric_limits<uint32_t>::max())
1582 return error("Alignment value is too large");
1583 AlignInBits = Record[11];
1584 }
1585 GlobalVariable *Attach = nullptr;
1586 if (auto *CMD = dyn_cast_or_null<ConstantAsMetadata>(Expr)) {
1587 if (auto *GV = dyn_cast<GlobalVariable>(CMD->getValue())) {
1588 Attach = GV;
1589 Expr = nullptr;
1590 } else if (auto *CI = dyn_cast<ConstantInt>(CMD->getValue())) {
1591 Expr = DIExpression::get(Context,
1592 {dwarf::DW_OP_constu, CI->getZExtValue(),
1593 dwarf::DW_OP_stack_value});
1594 } else {
1595 Expr = nullptr;
1596 }
1597 }
1598 DIGlobalVariable *DGV = GET_OR_DISTINCT(
1599 DIGlobalVariable,
1600 (Context, getMDOrNull(Record[1]), getMDString(Record[2]),
1601 getMDString(Record[3]), getMDOrNull(Record[4]), Record[5],
1602 getDITypeRefOrNull(Record[6]), Record[7], Record[8],
1603 getMDOrNull(Record[10]), AlignInBits));
1604
1605 DIGlobalVariableExpression *DGVE = nullptr;
1606 if (Attach || Expr)
1607 DGVE = DIGlobalVariableExpression::getDistinct(
1608 Context, DGV, Expr ? Expr : DIExpression::get(Context, {}));
1609 if (Attach)
1610 Attach->addDebugInfo(DGVE);
1611
1612 auto *MDNode = Expr ? cast<Metadata>(DGVE) : cast<Metadata>(DGV);
1613 MetadataList.assignValue(MDNode, NextMetadataNo);
1614 NextMetadataNo++;
1615 } else
1616 return error("Invalid record");
1617
1618 break;
1619 }
1620 case bitc::METADATA_LOCAL_VAR: {
1621 // 10th field is for the obseleted 'inlinedAt:' field.
1622 if (Record.size() < 8 || Record.size() > 10)
1623 return error("Invalid record");
1624
1625 IsDistinct = Record[0] & 1;
1626 bool HasAlignment = Record[0] & 2;
1627 // 2nd field used to be an artificial tag, either DW_TAG_auto_variable or
1628 // DW_TAG_arg_variable, if we have alignment flag encoded it means, that
1629 // this is newer version of record which doesn't have artificial tag.
1630 bool HasTag = !HasAlignment && Record.size() > 8;
1631 DINode::DIFlags Flags = static_cast<DINode::DIFlags>(Record[7 + HasTag]);
1632 uint32_t AlignInBits = 0;
1633 if (HasAlignment) {
1634 if (Record[8 + HasTag] > (uint64_t)std::numeric_limits<uint32_t>::max())
1635 return error("Alignment value is too large");
1636 AlignInBits = Record[8 + HasTag];
1637 }
1638 MetadataList.assignValue(
1639 GET_OR_DISTINCT(DILocalVariable,
1640 (Context, getMDOrNull(Record[1 + HasTag]),
1641 getMDString(Record[2 + HasTag]),
1642 getMDOrNull(Record[3 + HasTag]), Record[4 + HasTag],
1643 getDITypeRefOrNull(Record[5 + HasTag]),
1644 Record[6 + HasTag], Flags, AlignInBits)),
1645 NextMetadataNo);
1646 NextMetadataNo++;
1647 break;
1648 }
1649 case bitc::METADATA_EXPRESSION: {
1650 if (Record.size() < 1)
1651 return error("Invalid record");
1652
1653 IsDistinct = Record[0] & 1;
1654 uint64_t Version = Record[0] >> 1;
1655 auto Elts = MutableArrayRef<uint64_t>(Record).slice(1);
1656
1657 SmallVector<uint64_t, 6> Buffer;
1658 if (Error Err = upgradeDIExpression(Version, Elts, Buffer))
1659 return Err;
1660
1661 MetadataList.assignValue(
1662 GET_OR_DISTINCT(DIExpression, (Context, Elts)), NextMetadataNo);
1663 NextMetadataNo++;
1664 break;
1665 }
1666 case bitc::METADATA_GLOBAL_VAR_EXPR: {
1667 if (Record.size() != 3)
1668 return error("Invalid record");
1669
1670 IsDistinct = Record[0];
1671 Metadata *Expr = getMDOrNull(Record[2]);
1672 if (!Expr)
1673 Expr = DIExpression::get(Context, {});
1674 MetadataList.assignValue(
1675 GET_OR_DISTINCT(DIGlobalVariableExpression,
1676 (Context, getMDOrNull(Record[1]), Expr)),
1677 NextMetadataNo);
1678 NextMetadataNo++;
1679 break;
1680 }
1681 case bitc::METADATA_OBJC_PROPERTY: {
1682 if (Record.size() != 8)
1683 return error("Invalid record");
1684
1685 IsDistinct = Record[0];
1686 MetadataList.assignValue(
1687 GET_OR_DISTINCT(DIObjCProperty,
1688 (Context, getMDString(Record[1]),
1689 getMDOrNull(Record[2]), Record[3],
1690 getMDString(Record[4]), getMDString(Record[5]),
1691 Record[6], getDITypeRefOrNull(Record[7]))),
1692 NextMetadataNo);
1693 NextMetadataNo++;
1694 break;
1695 }
1696 case bitc::METADATA_IMPORTED_ENTITY: {
1697 if (Record.size() != 6 && Record.size() != 7)
1698 return error("Invalid record");
1699
1700 IsDistinct = Record[0];
1701 bool HasFile = (Record.size() == 7);
1702 MetadataList.assignValue(
1703 GET_OR_DISTINCT(DIImportedEntity,
1704 (Context, Record[1], getMDOrNull(Record[2]),
1705 getDITypeRefOrNull(Record[3]),
1706 HasFile ? getMDOrNull(Record[6]) : nullptr,
1707 HasFile ? Record[4] : 0, getMDString(Record[5]))),
1708 NextMetadataNo);
1709 NextMetadataNo++;
1710 break;
1711 }
1712 case bitc::METADATA_STRING_OLD: {
1713 std::string String(Record.begin(), Record.end());
1714
1715 // Test for upgrading !llvm.loop.
1716 HasSeenOldLoopTags |= mayBeOldLoopAttachmentTag(String);
1717 ++NumMDStringLoaded;
1718 Metadata *MD = MDString::get(Context, String);
1719 MetadataList.assignValue(MD, NextMetadataNo);
1720 NextMetadataNo++;
1721 break;
1722 }
1723 case bitc::METADATA_STRINGS: {
1724 auto CreateNextMDString = [&](StringRef Str) {
1725 ++NumMDStringLoaded;
1726 MetadataList.assignValue(MDString::get(Context, Str), NextMetadataNo);
1727 NextMetadataNo++;
1728 };
1729 if (Error Err = parseMetadataStrings(Record, Blob, CreateNextMDString))
1730 return Err;
1731 break;
1732 }
1733 case bitc::METADATA_GLOBAL_DECL_ATTACHMENT: {
1734 if (Record.size() % 2 == 0)
1735 return error("Invalid record");
1736 unsigned ValueID = Record[0];
1737 if (ValueID >= ValueList.size())
1738 return error("Invalid record");
1739 if (auto *GO = dyn_cast<GlobalObject>(ValueList[ValueID]))
1740 if (Error Err = parseGlobalObjectAttachment(
1741 *GO, ArrayRef<uint64_t>(Record).slice(1)))
1742 return Err;
1743 break;
1744 }
1745 case bitc::METADATA_KIND: {
1746 // Support older bitcode files that had METADATA_KIND records in a
1747 // block with METADATA_BLOCK_ID.
1748 if (Error Err = parseMetadataKindRecord(Record))
1749 return Err;
1750 break;
1751 }
1752 }
1753 return Error::success();
1754#undef GET_OR_DISTINCT
1755}
1756
1757Error MetadataLoader::MetadataLoaderImpl::parseMetadataStrings(
1758 ArrayRef<uint64_t> Record, StringRef Blob,
1759 function_ref<void(StringRef)> CallBack) {
1760 // All the MDStrings in the block are emitted together in a single
1761 // record. The strings are concatenated and stored in a blob along with
1762 // their sizes.
1763 if (Record.size() != 2)
1764 return error("Invalid record: metadata strings layout");
1765
1766 unsigned NumStrings = Record[0];
1767 unsigned StringsOffset = Record[1];
1768 if (!NumStrings)
1769 return error("Invalid record: metadata strings with no strings");
1770 if (StringsOffset > Blob.size())
1771 return error("Invalid record: metadata strings corrupt offset");
1772
1773 StringRef Lengths = Blob.slice(0, StringsOffset);
1774 SimpleBitstreamCursor R(Lengths);
1775
1776 StringRef Strings = Blob.drop_front(StringsOffset);
1777 do {
1778 if (R.AtEndOfStream())
1779 return error("Invalid record: metadata strings bad length");
1780
1781 unsigned Size = R.ReadVBR(6);
1782 if (Strings.size() < Size)
1783 return error("Invalid record: metadata strings truncated chars");
1784
1785 CallBack(Strings.slice(0, Size));
1786 Strings = Strings.drop_front(Size);
1787 } while (--NumStrings);
1788
1789 return Error::success();
1790}
1791
1792Error MetadataLoader::MetadataLoaderImpl::parseGlobalObjectAttachment(
1793 GlobalObject &GO, ArrayRef<uint64_t> Record) {
1794 assert(Record.size() % 2 == 0)(static_cast <bool> (Record.size() % 2 == 0) ? void (0)
: __assert_fail ("Record.size() % 2 == 0", "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 1794, __extension__ __PRETTY_FUNCTION__))
;
1795 for (unsigned I = 0, E = Record.size(); I != E; I += 2) {
1796 auto K = MDKindMap.find(Record[I]);
1797 if (K == MDKindMap.end())
1798 return error("Invalid ID");
1799 MDNode *MD = MetadataList.getMDNodeFwdRefOrNull(Record[I + 1]);
1800 if (!MD)
1801 return error("Invalid metadata attachment");
1802 GO.addMetadata(K->second, *MD);
1803 }
1804 return Error::success();
1805}
1806
1807/// Parse metadata attachments.
1808Error MetadataLoader::MetadataLoaderImpl::parseMetadataAttachment(
1809 Function &F, const SmallVectorImpl<Instruction *> &InstructionList) {
1810 if (Stream.EnterSubBlock(bitc::METADATA_ATTACHMENT_ID))
1811 return error("Invalid record");
1812
1813 SmallVector<uint64_t, 64> Record;
1814 PlaceholderQueue Placeholders;
1815
1816 while (true) {
1817 BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
1818
1819 switch (Entry.Kind) {
1820 case BitstreamEntry::SubBlock: // Handled for us already.
1821 case BitstreamEntry::Error:
1822 return error("Malformed block");
1823 case BitstreamEntry::EndBlock:
1824 resolveForwardRefsAndPlaceholders(Placeholders);
1825 return Error::success();
1826 case BitstreamEntry::Record:
1827 // The interesting case.
1828 break;
1829 }
1830
1831 // Read a metadata attachment record.
1832 Record.clear();
1833 ++NumMDRecordLoaded;
1834 switch (Stream.readRecord(Entry.ID, Record)) {
1835 default: // Default behavior: ignore.
1836 break;
1837 case bitc::METADATA_ATTACHMENT: {
1838 unsigned RecordLength = Record.size();
1839 if (Record.empty())
1840 return error("Invalid record");
1841 if (RecordLength % 2 == 0) {
1842 // A function attachment.
1843 if (Error Err = parseGlobalObjectAttachment(F, Record))
1844 return Err;
1845 continue;
1846 }
1847
1848 // An instruction attachment.
1849 Instruction *Inst = InstructionList[Record[0]];
1850 for (unsigned i = 1; i != RecordLength; i = i + 2) {
1851 unsigned Kind = Record[i];
1852 DenseMap<unsigned, unsigned>::iterator I = MDKindMap.find(Kind);
1853 if (I == MDKindMap.end())
1854 return error("Invalid ID");
1855 if (I->second == LLVMContext::MD_tbaa && StripTBAA)
1856 continue;
1857
1858 auto Idx = Record[i + 1];
1859 if (Idx < (MDStringRef.size() + GlobalMetadataBitPosIndex.size()) &&
1860 !MetadataList.lookup(Idx)) {
1861 // Load the attachment if it is in the lazy-loadable range and hasn't
1862 // been loaded yet.
1863 lazyLoadOneMetadata(Idx, Placeholders);
1864 resolveForwardRefsAndPlaceholders(Placeholders);
1865 }
1866
1867 Metadata *Node = MetadataList.getMetadataFwdRef(Idx);
1868 if (isa<LocalAsMetadata>(Node))
1869 // Drop the attachment. This used to be legal, but there's no
1870 // upgrade path.
1871 break;
1872 MDNode *MD = dyn_cast_or_null<MDNode>(Node);
1873 if (!MD)
1874 return error("Invalid metadata attachment");
1875
1876 if (HasSeenOldLoopTags && I->second == LLVMContext::MD_loop)
1877 MD = upgradeInstructionLoopAttachment(*MD);
1878
1879 if (I->second == LLVMContext::MD_tbaa) {
1880 assert(!MD->isTemporary() && "should load MDs before attachments")(static_cast <bool> (!MD->isTemporary() && "should load MDs before attachments"
) ? void (0) : __assert_fail ("!MD->isTemporary() && \"should load MDs before attachments\""
, "/build/llvm-toolchain-snapshot-7~svn325118/lib/Bitcode/Reader/MetadataLoader.cpp"
, 1880, __extension__ __PRETTY_FUNCTION__))
;
1881 MD = UpgradeTBAANode(*MD);
1882 }
1883 Inst->setMetadata(I->second, MD);
1884 }
1885 break;
1886 }
1887 }
1888 }
1889}
1890
1891/// Parse a single METADATA_KIND record, inserting result in MDKindMap.
1892Error MetadataLoader::MetadataLoaderImpl::parseMetadataKindRecord(
1893 SmallVectorImpl<uint64_t> &Record) {
1894 if (Record.size() < 2)
1895 return error("Invalid record");
1896
1897 unsigned Kind = Record[0];
1898 SmallString<8> Name(Record.begin() + 1, Record.end());
1899
1900 unsigned NewKind = TheModule.getMDKindID(Name.str());
1901 if (!MDKindMap.insert(std::make_pair(Kind, NewKind)).second)
1902 return error("Conflicting METADATA_KIND records");
1903 return Error::success();
1904}
1905
1906/// Parse the metadata kinds out of the METADATA_KIND_BLOCK.
1907Error MetadataLoader::MetadataLoaderImpl::parseMetadataKinds() {
1908 if (Stream.EnterSubBlock(bitc::METADATA_KIND_BLOCK_ID))
2
Assuming the condition is false
3
Taking false branch
1909 return error("Invalid record");
1910
1911 SmallVector<uint64_t, 64> Record;
1912
1913 // Read all the records.
1914 while (true) {
4
Loop condition is true. Entering loop body
1915 BitstreamEntry Entry = Stream.advanceSkippingSubblocks();
5
Calling 'BitstreamCursor::advanceSkippingSubblocks'
1916
1917 switch (Entry.Kind) {
1918 case BitstreamEntry::SubBlock: // Handled for us already.
1919 case BitstreamEntry::Error:
1920 return error("Malformed block");
1921 case BitstreamEntry::EndBlock:
1922 return Error::success();
1923 case BitstreamEntry::Record:
1924 // The interesting case.
1925 break;
1926 }
1927
1928 // Read a record.
1929 Record.clear();
1930 ++NumMDRecordLoaded;
1931 unsigned Code = Stream.readRecord(Entry.ID, Record);
1932 switch (Code) {
1933 default: // Default behavior: ignore.
1934 break;
1935 case bitc::METADATA_KIND: {
1936 if (Error Err = parseMetadataKindRecord(Record))
1937 return Err;
1938 break;
1939 }
1940 }
1941 }
1942}
1943
1944MetadataLoader &MetadataLoader::operator=(MetadataLoader &&RHS) {
1945 Pimpl = std::move(RHS.Pimpl);
1946 return *this;
1947}
1948MetadataLoader::MetadataLoader(MetadataLoader &&RHS)
1949 : Pimpl(std::move(RHS.Pimpl)) {}
1950
1951MetadataLoader::~MetadataLoader() = default;
1952MetadataLoader::MetadataLoader(BitstreamCursor &Stream, Module &TheModule,
1953 BitcodeReaderValueList &ValueList,
1954 bool IsImporting,
1955 std::function<Type *(unsigned)> getTypeByID)
1956 : Pimpl(llvm::make_unique<MetadataLoaderImpl>(
1957 Stream, TheModule, ValueList, std::move(getTypeByID), IsImporting)) {}
1958
1959Error MetadataLoader::parseMetadata(bool ModuleLevel) {
1960 return Pimpl->parseMetadata(ModuleLevel);
1961}
1962
1963bool MetadataLoader::hasFwdRefs() const { return Pimpl->hasFwdRefs(); }
1964
1965/// Return the given metadata, creating a replaceable forward reference if
1966/// necessary.
1967Metadata *MetadataLoader::getMetadataFwdRefOrLoad(unsigned Idx) {
1968 return Pimpl->getMetadataFwdRefOrLoad(Idx);
1969}
1970
1971MDNode *MetadataLoader::getMDNodeFwdRefOrNull(unsigned Idx) {
1972 return Pimpl->getMDNodeFwdRefOrNull(Idx);
1973}
1974
1975DISubprogram *MetadataLoader::lookupSubprogramForFunction(Function *F) {
1976 return Pimpl->lookupSubprogramForFunction(F);
1977}
1978
1979Error MetadataLoader::parseMetadataAttachment(
1980 Function &F, const SmallVectorImpl<Instruction *> &InstructionList) {
1981 return Pimpl->parseMetadataAttachment(F, InstructionList);
1982}
1983
1984Error MetadataLoader::parseMetadataKinds() {
1985 return Pimpl->parseMetadataKinds();
1
Calling 'MetadataLoaderImpl::parseMetadataKinds'
1986}
1987
1988void MetadataLoader::setStripTBAA(bool StripTBAA) {
1989 return Pimpl->setStripTBAA(StripTBAA);
1990}
1991
1992bool MetadataLoader::isStrippingTBAA() { return Pimpl->isStrippingTBAA(); }
1993
1994unsigned MetadataLoader::size() const { return Pimpl->size(); }
1995void MetadataLoader::shrinkTo(unsigned N) { return Pimpl->shrinkTo(N); }
1996
1997void MetadataLoader::upgradeDebugIntrinsics(Function &F) {
1998 return Pimpl->upgradeDebugIntrinsics(F);
1999}

/build/llvm-toolchain-snapshot-7~svn325118/include/llvm/Bitcode/BitstreamReader.h

1//===- BitstreamReader.h - Low-level bitstream reader interface -*- C++ -*-===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This header defines the BitstreamReader class. This class can be used to
11// read an arbitrary bitstream, regardless of its contents.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_BITCODE_BITSTREAMREADER_H
16#define LLVM_BITCODE_BITSTREAMREADER_H
17
18#include "llvm/ADT/ArrayRef.h"
19#include "llvm/ADT/SmallVector.h"
20#include "llvm/Bitcode/BitCodes.h"
21#include "llvm/Support/Endian.h"
22#include "llvm/Support/ErrorHandling.h"
23#include "llvm/Support/MathExtras.h"
24#include "llvm/Support/MemoryBuffer.h"
25#include <algorithm>
26#include <cassert>
27#include <climits>
28#include <cstddef>
29#include <cstdint>
30#include <memory>
31#include <string>
32#include <utility>
33#include <vector>
34
35namespace llvm {
36
37/// This class maintains the abbreviations read from a block info block.
38class BitstreamBlockInfo {
39public:
40 /// This contains information emitted to BLOCKINFO_BLOCK blocks. These
41 /// describe abbreviations that all blocks of the specified ID inherit.
42 struct BlockInfo {
43 unsigned BlockID;
44 std::vector<std::shared_ptr<BitCodeAbbrev>> Abbrevs;
45 std::string Name;
46 std::vector<std::pair<unsigned, std::string>> RecordNames;
47 };
48
49private:
50 std::vector<BlockInfo> BlockInfoRecords;
51
52public:
53 /// If there is block info for the specified ID, return it, otherwise return
54 /// null.
55 const BlockInfo *getBlockInfo(unsigned BlockID) const {
56 // Common case, the most recent entry matches BlockID.
57 if (!BlockInfoRecords.empty() && BlockInfoRecords.back().BlockID == BlockID)
58 return &BlockInfoRecords.back();
59
60 for (unsigned i = 0, e = static_cast<unsigned>(BlockInfoRecords.size());
61 i != e; ++i)
62 if (BlockInfoRecords[i].BlockID == BlockID)
63 return &BlockInfoRecords[i];
64 return nullptr;
65 }
66
67 BlockInfo &getOrCreateBlockInfo(unsigned BlockID) {
68 if (const BlockInfo *BI = getBlockInfo(BlockID))
69 return *const_cast<BlockInfo*>(BI);
70
71 // Otherwise, add a new record.
72 BlockInfoRecords.emplace_back();
73 BlockInfoRecords.back().BlockID = BlockID;
74 return BlockInfoRecords.back();
75 }
76};
77
78/// This represents a position within a bitstream. There may be multiple
79/// independent cursors reading within one bitstream, each maintaining their
80/// own local state.
81class SimpleBitstreamCursor {
82 ArrayRef<uint8_t> BitcodeBytes;
83 size_t NextChar = 0;
84
85public:
86 /// This is the current data we have pulled from the stream but have not
87 /// returned to the client. This is specifically and intentionally defined to
88 /// follow the word size of the host machine for efficiency. We use word_t in
89 /// places that are aware of this to make it perfectly explicit what is going
90 /// on.
91 using word_t = size_t;
92
93private:
94 word_t CurWord = 0;
95
96 /// This is the number of bits in CurWord that are valid. This is always from
97 /// [0...bits_of(size_t)-1] inclusive.
98 unsigned BitsInCurWord = 0;
99
100public:
101 static const size_t MaxChunkSize = sizeof(word_t) * 8;
102
103 SimpleBitstreamCursor() = default;
104 explicit SimpleBitstreamCursor(ArrayRef<uint8_t> BitcodeBytes)
105 : BitcodeBytes(BitcodeBytes) {}
106 explicit SimpleBitstreamCursor(StringRef BitcodeBytes)
107 : BitcodeBytes(reinterpret_cast<const uint8_t *>(BitcodeBytes.data()),
108 BitcodeBytes.size()) {}
109 explicit SimpleBitstreamCursor(MemoryBufferRef BitcodeBytes)
110 : SimpleBitstreamCursor(BitcodeBytes.getBuffer()) {}
111
112 bool canSkipToPos(size_t pos) const {
113 // pos can be skipped to if it is a valid address or one byte past the end.
114 return pos <= BitcodeBytes.size();
115 }
116
117 bool AtEndOfStream() {
118 return BitsInCurWord == 0 && BitcodeBytes.size() <= NextChar;
119 }
120
121 /// Return the bit # of the bit we are reading.
122 uint64_t GetCurrentBitNo() const {
123 return NextChar*CHAR_BIT8 - BitsInCurWord;
124 }
125
126 // Return the byte # of the current bit.
127 uint64_t getCurrentByteNo() const { return GetCurrentBitNo() / 8; }
128
129 ArrayRef<uint8_t> getBitcodeBytes() const { return BitcodeBytes; }
130
131 /// Reset the stream to the specified bit number.
132 void JumpToBit(uint64_t BitNo) {
133 size_t ByteNo = size_t(BitNo/8) & ~(sizeof(word_t)-1);
134 unsigned WordBitNo = unsigned(BitNo & (sizeof(word_t)*8-1));
135 assert(canSkipToPos(ByteNo) && "Invalid location")(static_cast <bool> (canSkipToPos(ByteNo) && "Invalid location"
) ? void (0) : __assert_fail ("canSkipToPos(ByteNo) && \"Invalid location\""
, "/build/llvm-toolchain-snapshot-7~svn325118/include/llvm/Bitcode/BitstreamReader.h"
, 135, __extension__ __PRETTY_FUNCTION__))
;
136
137 // Move the cursor to the right word.
138 NextChar = ByteNo;
139 BitsInCurWord = 0;
140
141 // Skip over any bits that are already consumed.
142 if (WordBitNo)
143 Read(WordBitNo);
144 }
145
146 /// Get a pointer into the bitstream at the specified byte offset.
147 const uint8_t *getPointerToByte(uint64_t ByteNo, uint64_t NumBytes) {
148 return BitcodeBytes.data() + ByteNo;
149 }
150
151 /// Get a pointer into the bitstream at the specified bit offset.
152 ///
153 /// The bit offset must be on a byte boundary.
154 const uint8_t *getPointerToBit(uint64_t BitNo, uint64_t NumBytes) {
155 assert(!(BitNo % 8) && "Expected bit on byte boundary")(static_cast <bool> (!(BitNo % 8) && "Expected bit on byte boundary"
) ? void (0) : __assert_fail ("!(BitNo % 8) && \"Expected bit on byte boundary\""
, "/build/llvm-toolchain-snapshot-7~svn325118/include/llvm/Bitcode/BitstreamReader.h"
, 155, __extension__ __PRETTY_FUNCTION__))
;
156 return getPointerToByte(BitNo / 8, NumBytes);
157 }
158
159 void fillCurWord() {
160 if (NextChar >= BitcodeBytes.size())
161 report_fatal_error("Unexpected end of file");
162
163 // Read the next word from the stream.
164 const uint8_t *NextCharPtr = BitcodeBytes.data() + NextChar;
165 unsigned BytesRead;
166 if (BitcodeBytes.size() >= NextChar + sizeof(word_t)) {
167 BytesRead = sizeof(word_t);
168 CurWord =
169 support::endian::read<word_t, support::little, support::unaligned>(
170 NextCharPtr);
171 } else {
172 // Short read.
173 BytesRead = BitcodeBytes.size() - NextChar;
174 CurWord = 0;
175 for (unsigned B = 0; B != BytesRead; ++B)
176 CurWord |= uint64_t(NextCharPtr[B]) << (B * 8);
177 }
178 NextChar += BytesRead;
179 BitsInCurWord = BytesRead * 8;
180 }
181
182 word_t Read(unsigned NumBits) {
183 static const unsigned BitsInWord = MaxChunkSize;
184
185 assert(NumBits && NumBits <= BitsInWord &&(static_cast <bool> (NumBits && NumBits <= BitsInWord
&& "Cannot return zero or more than BitsInWord bits!"
) ? void (0) : __assert_fail ("NumBits && NumBits <= BitsInWord && \"Cannot return zero or more than BitsInWord bits!\""
, "/build/llvm-toolchain-snapshot-7~svn325118/include/llvm/Bitcode/BitstreamReader.h"
, 186, __extension__ __PRETTY_FUNCTION__))
186 "Cannot return zero or more than BitsInWord bits!")(static_cast <bool> (NumBits && NumBits <= BitsInWord
&& "Cannot return zero or more than BitsInWord bits!"
) ? void (0) : __assert_fail ("NumBits && NumBits <= BitsInWord && \"Cannot return zero or more than BitsInWord bits!\""
, "/build/llvm-toolchain-snapshot-7~svn325118/include/llvm/Bitcode/BitstreamReader.h"
, 186, __extension__ __PRETTY_FUNCTION__))
;
187
188 static const unsigned Mask = sizeof(word_t) > 4 ? 0x3f : 0x1f;
12
'?' condition is true
189
190 // If the field is fully contained by CurWord, return it quickly.
191 if (BitsInCurWord >= NumBits) {
13
Taking false branch
192 word_t R = CurWord & (~word_t(0) >> (BitsInWord - NumBits));
193
194 // Use a mask to avoid undefined behavior.
195 CurWord >>= (NumBits & Mask);
196
197 BitsInCurWord -= NumBits;
198 return R;
199 }
200
201 word_t R = BitsInCurWord ? CurWord : 0;
14
'?' condition is true
202 unsigned BitsLeft = NumBits - BitsInCurWord;
203
204 fillCurWord();
205
206 // If we run out of data, abort.
207 if (BitsLeft > BitsInCurWord)
15
Assuming the condition is false
16
Taking false branch
208 report_fatal_error("Unexpected end of file");
209
210 word_t R2 = CurWord & (~word_t(0) >> (BitsInWord - BitsLeft));
17
The result of the right shift is undefined due to shifting by '64', which is greater or equal to the width of type 'llvm::SimpleBitstreamCursor::word_t'
211
212 // Use a mask to avoid undefined behavior.
213 CurWord >>= (BitsLeft & Mask);
214
215 BitsInCurWord -= BitsLeft;
216
217 R |= R2 << (NumBits - BitsLeft);
218
219 return R;
220 }
221
222 uint32_t ReadVBR(unsigned NumBits) {
223 uint32_t Piece = Read(NumBits);
224 if ((Piece & (1U << (NumBits-1))) == 0)
225 return Piece;
226
227 uint32_t Result = 0;
228 unsigned NextBit = 0;
229 while (true) {
230 Result |= (Piece & ((1U << (NumBits-1))-1)) << NextBit;
231
232 if ((Piece & (1U << (NumBits-1))) == 0)
233 return Result;
234
235 NextBit += NumBits-1;
236 Piece = Read(NumBits);
237 }
238 }
239
240 // Read a VBR that may have a value up to 64-bits in size. The chunk size of
241 // the VBR must still be <= 32 bits though.
242 uint64_t ReadVBR64(unsigned NumBits) {
243 uint32_t Piece = Read(NumBits);
244 if ((Piece & (1U << (NumBits-1))) == 0)
245 return uint64_t(Piece);
246
247 uint64_t Result = 0;
248 unsigned NextBit = 0;
249 while (true) {
250 Result |= uint64_t(Piece & ((1U << (NumBits-1))-1)) << NextBit;
251
252 if ((Piece & (1U << (NumBits-1))) == 0)
253 return Result;
254
255 NextBit += NumBits-1;
256 Piece = Read(NumBits);
257 }
258 }
259
260 void SkipToFourByteBoundary() {
261 // If word_t is 64-bits and if we've read less than 32 bits, just dump
262 // the bits we have up to the next 32-bit boundary.
263 if (sizeof(word_t) > 4 &&
264 BitsInCurWord >= 32) {
265 CurWord >>= BitsInCurWord-32;
266 BitsInCurWord = 32;
267 return;
268 }
269
270 BitsInCurWord = 0;
271 }
272
273 /// Skip to the end of the file.
274 void skipToEnd() { NextChar = BitcodeBytes.size(); }
275};
276
277/// When advancing through a bitstream cursor, each advance can discover a few
278/// different kinds of entries:
279struct BitstreamEntry {
280 enum {
281 Error, // Malformed bitcode was found.
282 EndBlock, // We've reached the end of the current block, (or the end of the
283 // file, which is treated like a series of EndBlock records.
284 SubBlock, // This is the start of a new subblock of a specific ID.
285 Record // This is a record with a specific AbbrevID.
286 } Kind;
287
288 unsigned ID;
289
290 static BitstreamEntry getError() {
291 BitstreamEntry E; E.Kind = Error; return E;
292 }
293
294 static BitstreamEntry getEndBlock() {
295 BitstreamEntry E; E.Kind = EndBlock; return E;
296 }
297
298 static BitstreamEntry getSubBlock(unsigned ID) {
299 BitstreamEntry E; E.Kind = SubBlock; E.ID = ID; return E;
300 }
301
302 static BitstreamEntry getRecord(unsigned AbbrevID) {
303 BitstreamEntry E; E.Kind = Record; E.ID = AbbrevID; return E;
304 }
305};
306
307/// This represents a position within a bitcode file, implemented on top of a
308/// SimpleBitstreamCursor.
309///
310/// Unlike iterators, BitstreamCursors are heavy-weight objects that should not
311/// be passed by value.
312class BitstreamCursor : SimpleBitstreamCursor {
313 // This is the declared size of code values used for the current block, in
314 // bits.
315 unsigned CurCodeSize = 2;
316
317 /// Abbrevs installed at in this block.
318 std::vector<std::shared_ptr<BitCodeAbbrev>> CurAbbrevs;
319
320 struct Block {
321 unsigned PrevCodeSize;
322 std::vector<std::shared_ptr<BitCodeAbbrev>> PrevAbbrevs;
323
324 explicit Block(unsigned PCS) : PrevCodeSize(PCS) {}
325 };
326
327 /// This tracks the codesize of parent blocks.
328 SmallVector<Block, 8> BlockScope;
329
330 BitstreamBlockInfo *BlockInfo = nullptr;
331
332public:
333 static const size_t MaxChunkSize = sizeof(word_t) * 8;
334
335 BitstreamCursor() = default;
336 explicit BitstreamCursor(ArrayRef<uint8_t> BitcodeBytes)
337 : SimpleBitstreamCursor(BitcodeBytes) {}
338 explicit BitstreamCursor(StringRef BitcodeBytes)
339 : SimpleBitstreamCursor(BitcodeBytes) {}
340 explicit BitstreamCursor(MemoryBufferRef BitcodeBytes)
341 : SimpleBitstreamCursor(BitcodeBytes) {}
342
343 using SimpleBitstreamCursor::canSkipToPos;
344 using SimpleBitstreamCursor::AtEndOfStream;
345 using SimpleBitstreamCursor::getBitcodeBytes;
346 using SimpleBitstreamCursor::GetCurrentBitNo;
347 using SimpleBitstreamCursor::getCurrentByteNo;
348 using SimpleBitstreamCursor::getPointerToByte;
349 using SimpleBitstreamCursor::JumpToBit;
350 using SimpleBitstreamCursor::fillCurWord;
351 using SimpleBitstreamCursor::Read;
352 using SimpleBitstreamCursor::ReadVBR;
353 using SimpleBitstreamCursor::ReadVBR64;
354
355 /// Return the number of bits used to encode an abbrev #.
356 unsigned getAbbrevIDWidth() const { return CurCodeSize; }
357
358 /// Flags that modify the behavior of advance().
359 enum {
360 /// If this flag is used, the advance() method does not automatically pop
361 /// the block scope when the end of a block is reached.
362 AF_DontPopBlockAtEnd = 1,
363
364 /// If this flag is used, abbrev entries are returned just like normal
365 /// records.
366 AF_DontAutoprocessAbbrevs = 2
367 };
368
369 /// Advance the current bitstream, returning the next entry in the stream.
370 BitstreamEntry advance(unsigned Flags = 0) {
371 while (true) {
8
Loop condition is true. Entering loop body
372 if (AtEndOfStream())
9
Taking false branch
373 return BitstreamEntry::getError();
374
375 unsigned Code = ReadCode();
10
Calling 'BitstreamCursor::ReadCode'
376 if (Code == bitc::END_BLOCK) {
377 // Pop the end of the block unless Flags tells us not to.
378 if (!(Flags & AF_DontPopBlockAtEnd) && ReadBlockEnd())
379 return BitstreamEntry::getError();
380 return BitstreamEntry::getEndBlock();
381 }
382
383 if (Code == bitc::ENTER_SUBBLOCK)
384 return BitstreamEntry::getSubBlock(ReadSubBlockID());
385
386 if (Code == bitc::DEFINE_ABBREV &&
387 !(Flags & AF_DontAutoprocessAbbrevs)) {
388 // We read and accumulate abbrev's, the client can't do anything with
389 // them anyway.
390 ReadAbbrevRecord();
391 continue;
392 }
393
394 return BitstreamEntry::getRecord(Code);
395 }
396 }
397
398 /// This is a convenience function for clients that don't expect any
399 /// subblocks. This just skips over them automatically.
400 BitstreamEntry advanceSkippingSubblocks(unsigned Flags = 0) {
401 while (true) {
6
Loop condition is true. Entering loop body
402 // If we found a normal entry, return it.
403 BitstreamEntry Entry = advance(Flags);
7
Calling 'BitstreamCursor::advance'
404 if (Entry.Kind != BitstreamEntry::SubBlock)
405 return Entry;
406
407 // If we found a sub-block, just skip over it and check the next entry.
408 if (SkipBlock())
409 return BitstreamEntry::getError();
410 }
411 }
412
413 unsigned ReadCode() {
414 return Read(CurCodeSize);
11
Calling 'SimpleBitstreamCursor::Read'
415 }
416
417 // Block header:
418 // [ENTER_SUBBLOCK, blockid, newcodelen, <align4bytes>, blocklen]
419
420 /// Having read the ENTER_SUBBLOCK code, read the BlockID for the block.
421 unsigned ReadSubBlockID() {
422 return ReadVBR(bitc::BlockIDWidth);
423 }
424
425 /// Having read the ENTER_SUBBLOCK abbrevid and a BlockID, skip over the body
426 /// of this block. If the block record is malformed, return true.
427 bool SkipBlock() {
428 // Read and ignore the codelen value. Since we are skipping this block, we
429 // don't care what code widths are used inside of it.
430 ReadVBR(bitc::CodeLenWidth);
431 SkipToFourByteBoundary();
432 unsigned NumFourBytes = Read(bitc::BlockSizeWidth);
433
434 // Check that the block wasn't partially defined, and that the offset isn't
435 // bogus.
436 size_t SkipTo = GetCurrentBitNo() + NumFourBytes*4*8;
437 if (AtEndOfStream() || !canSkipToPos(SkipTo/8))
438 return true;
439
440 JumpToBit(SkipTo);
441 return false;
442 }
443
444 /// Having read the ENTER_SUBBLOCK abbrevid, enter the block, and return true
445 /// if the block has an error.
446 bool EnterSubBlock(unsigned BlockID, unsigned *NumWordsP = nullptr);
447
448 bool ReadBlockEnd() {
449 if (BlockScope.empty()) return true;
450
451 // Block tail:
452 // [END_BLOCK, <align4bytes>]
453 SkipToFourByteBoundary();
454
455 popBlockScope();
456 return false;
457 }
458
459private:
460 void popBlockScope() {
461 CurCodeSize = BlockScope.back().PrevCodeSize;
462
463 CurAbbrevs = std::move(BlockScope.back().PrevAbbrevs);
464 BlockScope.pop_back();
465 }
466
467 //===--------------------------------------------------------------------===//
468 // Record Processing
469 //===--------------------------------------------------------------------===//
470
471public:
472 /// Return the abbreviation for the specified AbbrevId.
473 const BitCodeAbbrev *getAbbrev(unsigned AbbrevID) {
474 unsigned AbbrevNo = AbbrevID - bitc::FIRST_APPLICATION_ABBREV;
475 if (AbbrevNo >= CurAbbrevs.size())
476 report_fatal_error("Invalid abbrev number");
477 return CurAbbrevs[AbbrevNo].get();
478 }
479
480 /// Read the current record and discard it, returning the code for the record.
481 unsigned skipRecord(unsigned AbbrevID);
482
483 unsigned readRecord(unsigned AbbrevID, SmallVectorImpl<uint64_t> &Vals,
484 StringRef *Blob = nullptr);
485
486 //===--------------------------------------------------------------------===//
487 // Abbrev Processing
488 //===--------------------------------------------------------------------===//
489 void ReadAbbrevRecord();
490
491 /// Read and return a block info block from the bitstream. If an error was
492 /// encountered, return None.
493 ///
494 /// \param ReadBlockInfoNames Whether to read block/record name information in
495 /// the BlockInfo block. Only llvm-bcanalyzer uses this.
496 Optional<BitstreamBlockInfo>
497 ReadBlockInfoBlock(bool ReadBlockInfoNames = false);
498
499 /// Set the block info to be used by this BitstreamCursor to interpret
500 /// abbreviated records.
501 void setBlockInfo(BitstreamBlockInfo *BI) { BlockInfo = BI; }
502};
503
504} // end llvm namespace
505
506#endif // LLVM_BITCODE_BITSTREAMREADER_H