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1 //=-- CoverageMapping.h - Code coverage mapping support ---------*- 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 // Code coverage mapping data is generated by clang and read by
11 // llvm-cov to show code coverage statistics for a file.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_PROFILEDATA_COVERAGEMAPPING_H_
16 #define LLVM_PROFILEDATA_COVERAGEMAPPING_H_
17 
18 #include "llvm/ADT/ArrayRef.h"
19 #include "llvm/ADT/DenseMap.h"
20 #include "llvm/ADT/Hashing.h"
21 #include "llvm/ADT/Triple.h"
22 #include "llvm/ADT/iterator.h"
23 #include "llvm/ProfileData/InstrProf.h"
24 #include "llvm/Support/Debug.h"
25 #include "llvm/Support/Endian.h"
26 #include "llvm/Support/raw_ostream.h"
27 #include <system_error>
28 #include <tuple>
29 
30 namespace llvm {
31 namespace coverage {
32 
33 enum class coveragemap_error {
34   success = 0,
35   eof,
36   no_data_found,
37   unsupported_version,
38   truncated,
39   malformed
40 };
41 
42 const std::error_category &coveragemap_category();
43 
make_error_code(coveragemap_error E)44 inline std::error_code make_error_code(coveragemap_error E) {
45   return std::error_code(static_cast<int>(E), coveragemap_category());
46 }
47 
48 class CoverageMapError : public ErrorInfo<CoverageMapError> {
49 public:
CoverageMapError(coveragemap_error Err)50   CoverageMapError(coveragemap_error Err) : Err(Err) {
51     assert(Err != coveragemap_error::success && "Not an error");
52   }
53 
54   std::string message() const override;
55 
log(raw_ostream & OS)56   void log(raw_ostream &OS) const override { OS << message(); }
57 
convertToErrorCode()58   std::error_code convertToErrorCode() const override {
59     return make_error_code(Err);
60   }
61 
get()62   coveragemap_error get() const { return Err; }
63 
64   static char ID;
65 
66 private:
67   coveragemap_error Err;
68 };
69 
70 } // end of coverage namespace.
71 } // end of llvm namespace
72 
73 namespace llvm {
74 class IndexedInstrProfReader;
75 namespace coverage {
76 
77 class CoverageMappingReader;
78 
79 class CoverageMapping;
80 struct CounterExpressions;
81 
82 /// \brief A Counter is an abstract value that describes how to compute the
83 /// execution count for a region of code using the collected profile count data.
84 struct Counter {
85   enum CounterKind { Zero, CounterValueReference, Expression };
86   static const unsigned EncodingTagBits = 2;
87   static const unsigned EncodingTagMask = 0x3;
88   static const unsigned EncodingCounterTagAndExpansionRegionTagBits =
89       EncodingTagBits + 1;
90 
91 private:
92   CounterKind Kind;
93   unsigned ID;
94 
CounterCounter95   Counter(CounterKind Kind, unsigned ID) : Kind(Kind), ID(ID) {}
96 
97 public:
CounterCounter98   Counter() : Kind(Zero), ID(0) {}
99 
getKindCounter100   CounterKind getKind() const { return Kind; }
101 
isZeroCounter102   bool isZero() const { return Kind == Zero; }
103 
isExpressionCounter104   bool isExpression() const { return Kind == Expression; }
105 
getCounterIDCounter106   unsigned getCounterID() const { return ID; }
107 
getExpressionIDCounter108   unsigned getExpressionID() const { return ID; }
109 
110   friend bool operator==(const Counter &LHS, const Counter &RHS) {
111     return LHS.Kind == RHS.Kind && LHS.ID == RHS.ID;
112   }
113 
114   friend bool operator!=(const Counter &LHS, const Counter &RHS) {
115     return !(LHS == RHS);
116   }
117 
118   friend bool operator<(const Counter &LHS, const Counter &RHS) {
119     return std::tie(LHS.Kind, LHS.ID) < std::tie(RHS.Kind, RHS.ID);
120   }
121 
122   /// \brief Return the counter that represents the number zero.
getZeroCounter123   static Counter getZero() { return Counter(); }
124 
125   /// \brief Return the counter that corresponds to a specific profile counter.
getCounterCounter126   static Counter getCounter(unsigned CounterId) {
127     return Counter(CounterValueReference, CounterId);
128   }
129 
130   /// \brief Return the counter that corresponds to a specific
131   /// addition counter expression.
getExpressionCounter132   static Counter getExpression(unsigned ExpressionId) {
133     return Counter(Expression, ExpressionId);
134   }
135 };
136 
137 /// \brief A Counter expression is a value that represents an arithmetic
138 /// operation with two counters.
139 struct CounterExpression {
140   enum ExprKind { Subtract, Add };
141   ExprKind Kind;
142   Counter LHS, RHS;
143 
CounterExpressionCounterExpression144   CounterExpression(ExprKind Kind, Counter LHS, Counter RHS)
145       : Kind(Kind), LHS(LHS), RHS(RHS) {}
146 };
147 
148 /// \brief A Counter expression builder is used to construct the
149 /// counter expressions. It avoids unnecessary duplication
150 /// and simplifies algebraic expressions.
151 class CounterExpressionBuilder {
152   /// \brief A list of all the counter expressions
153   std::vector<CounterExpression> Expressions;
154   /// \brief A lookup table for the index of a given expression.
155   llvm::DenseMap<CounterExpression, unsigned> ExpressionIndices;
156 
157   /// \brief Return the counter which corresponds to the given expression.
158   ///
159   /// If the given expression is already stored in the builder, a counter
160   /// that references that expression is returned. Otherwise, the given
161   /// expression is added to the builder's collection of expressions.
162   Counter get(const CounterExpression &E);
163 
164   /// \brief Gather the terms of the expression tree for processing.
165   ///
166   /// This collects each addition and subtraction referenced by the counter into
167   /// a sequence that can be sorted and combined to build a simplified counter
168   /// expression.
169   void extractTerms(Counter C, int Sign,
170                     SmallVectorImpl<std::pair<unsigned, int>> &Terms);
171 
172   /// \brief Simplifies the given expression tree
173   /// by getting rid of algebraically redundant operations.
174   Counter simplify(Counter ExpressionTree);
175 
176 public:
getExpressions()177   ArrayRef<CounterExpression> getExpressions() const { return Expressions; }
178 
179   /// \brief Return a counter that represents the expression
180   /// that adds LHS and RHS.
181   Counter add(Counter LHS, Counter RHS);
182 
183   /// \brief Return a counter that represents the expression
184   /// that subtracts RHS from LHS.
185   Counter subtract(Counter LHS, Counter RHS);
186 };
187 
188 /// \brief A Counter mapping region associates a source range with
189 /// a specific counter.
190 struct CounterMappingRegion {
191   enum RegionKind {
192     /// \brief A CodeRegion associates some code with a counter
193     CodeRegion,
194 
195     /// \brief An ExpansionRegion represents a file expansion region that
196     /// associates a source range with the expansion of a virtual source file,
197     /// such as for a macro instantiation or #include file.
198     ExpansionRegion,
199 
200     /// \brief A SkippedRegion represents a source range with code that
201     /// was skipped by a preprocessor or similar means.
202     SkippedRegion
203   };
204 
205   Counter Count;
206   unsigned FileID, ExpandedFileID;
207   unsigned LineStart, ColumnStart, LineEnd, ColumnEnd;
208   RegionKind Kind;
209 
CounterMappingRegionCounterMappingRegion210   CounterMappingRegion(Counter Count, unsigned FileID, unsigned ExpandedFileID,
211                        unsigned LineStart, unsigned ColumnStart,
212                        unsigned LineEnd, unsigned ColumnEnd, RegionKind Kind)
213       : Count(Count), FileID(FileID), ExpandedFileID(ExpandedFileID),
214         LineStart(LineStart), ColumnStart(ColumnStart), LineEnd(LineEnd),
215         ColumnEnd(ColumnEnd), Kind(Kind) {}
216 
217   static CounterMappingRegion
makeRegionCounterMappingRegion218   makeRegion(Counter Count, unsigned FileID, unsigned LineStart,
219              unsigned ColumnStart, unsigned LineEnd, unsigned ColumnEnd) {
220     return CounterMappingRegion(Count, FileID, 0, LineStart, ColumnStart,
221                                 LineEnd, ColumnEnd, CodeRegion);
222   }
223 
224   static CounterMappingRegion
makeExpansionCounterMappingRegion225   makeExpansion(unsigned FileID, unsigned ExpandedFileID, unsigned LineStart,
226                 unsigned ColumnStart, unsigned LineEnd, unsigned ColumnEnd) {
227     return CounterMappingRegion(Counter(), FileID, ExpandedFileID, LineStart,
228                                 ColumnStart, LineEnd, ColumnEnd,
229                                 ExpansionRegion);
230   }
231 
232   static CounterMappingRegion
makeSkippedCounterMappingRegion233   makeSkipped(unsigned FileID, unsigned LineStart, unsigned ColumnStart,
234               unsigned LineEnd, unsigned ColumnEnd) {
235     return CounterMappingRegion(Counter(), FileID, 0, LineStart, ColumnStart,
236                                 LineEnd, ColumnEnd, SkippedRegion);
237   }
238 
239 
startLocCounterMappingRegion240   inline std::pair<unsigned, unsigned> startLoc() const {
241     return std::pair<unsigned, unsigned>(LineStart, ColumnStart);
242   }
243 
endLocCounterMappingRegion244   inline std::pair<unsigned, unsigned> endLoc() const {
245     return std::pair<unsigned, unsigned>(LineEnd, ColumnEnd);
246   }
247 
248   bool operator<(const CounterMappingRegion &Other) const {
249     if (FileID != Other.FileID)
250       return FileID < Other.FileID;
251     return startLoc() < Other.startLoc();
252   }
253 
containsCounterMappingRegion254   bool contains(const CounterMappingRegion &Other) const {
255     if (FileID != Other.FileID)
256       return false;
257     if (startLoc() > Other.startLoc())
258       return false;
259     if (endLoc() < Other.endLoc())
260       return false;
261     return true;
262   }
263 };
264 
265 /// \brief Associates a source range with an execution count.
266 struct CountedRegion : public CounterMappingRegion {
267   uint64_t ExecutionCount;
268 
CountedRegionCountedRegion269   CountedRegion(const CounterMappingRegion &R, uint64_t ExecutionCount)
270       : CounterMappingRegion(R), ExecutionCount(ExecutionCount) {}
271 };
272 
273 /// \brief A Counter mapping context is used to connect the counters,
274 /// expressions and the obtained counter values.
275 class CounterMappingContext {
276   ArrayRef<CounterExpression> Expressions;
277   ArrayRef<uint64_t> CounterValues;
278 
279 public:
280   CounterMappingContext(ArrayRef<CounterExpression> Expressions,
281                         ArrayRef<uint64_t> CounterValues = None)
Expressions(Expressions)282       : Expressions(Expressions), CounterValues(CounterValues) {}
283 
setCounts(ArrayRef<uint64_t> Counts)284   void setCounts(ArrayRef<uint64_t> Counts) { CounterValues = Counts; }
285 
286   void dump(const Counter &C, llvm::raw_ostream &OS) const;
dump(const Counter & C)287   void dump(const Counter &C) const { dump(C, dbgs()); }
288 
289   /// \brief Return the number of times that a region of code associated with
290   /// this counter was executed.
291   Expected<int64_t> evaluate(const Counter &C) const;
292 };
293 
294 /// \brief Code coverage information for a single function.
295 struct FunctionRecord {
296   /// \brief Raw function name.
297   std::string Name;
298   /// \brief Associated files.
299   std::vector<std::string> Filenames;
300   /// \brief Regions in the function along with their counts.
301   std::vector<CountedRegion> CountedRegions;
302   /// \brief The number of times this function was executed.
303   uint64_t ExecutionCount;
304 
FunctionRecordFunctionRecord305   FunctionRecord(StringRef Name, ArrayRef<StringRef> Filenames)
306       : Name(Name), Filenames(Filenames.begin(), Filenames.end()) {}
307 
pushRegionFunctionRecord308   void pushRegion(CounterMappingRegion Region, uint64_t Count) {
309     if (CountedRegions.empty())
310       ExecutionCount = Count;
311     CountedRegions.emplace_back(Region, Count);
312   }
313 };
314 
315 /// \brief Iterator over Functions, optionally filtered to a single file.
316 class FunctionRecordIterator
317     : public iterator_facade_base<FunctionRecordIterator,
318                                   std::forward_iterator_tag, FunctionRecord> {
319   ArrayRef<FunctionRecord> Records;
320   ArrayRef<FunctionRecord>::iterator Current;
321   StringRef Filename;
322 
323   /// \brief Skip records whose primary file is not \c Filename.
324   void skipOtherFiles();
325 
326 public:
327   FunctionRecordIterator(ArrayRef<FunctionRecord> Records_,
328                          StringRef Filename = "")
Records(Records_)329       : Records(Records_), Current(Records.begin()), Filename(Filename) {
330     skipOtherFiles();
331   }
332 
FunctionRecordIterator()333   FunctionRecordIterator() : Current(Records.begin()) {}
334 
335   bool operator==(const FunctionRecordIterator &RHS) const {
336     return Current == RHS.Current && Filename == RHS.Filename;
337   }
338 
339   const FunctionRecord &operator*() const { return *Current; }
340 
341   FunctionRecordIterator &operator++() {
342     assert(Current != Records.end() && "incremented past end");
343     ++Current;
344     skipOtherFiles();
345     return *this;
346   }
347 };
348 
349 /// \brief Coverage information for a macro expansion or #included file.
350 ///
351 /// When covered code has pieces that can be expanded for more detail, such as a
352 /// preprocessor macro use and its definition, these are represented as
353 /// expansions whose coverage can be looked up independently.
354 struct ExpansionRecord {
355   /// \brief The abstract file this expansion covers.
356   unsigned FileID;
357   /// \brief The region that expands to this record.
358   const CountedRegion &Region;
359   /// \brief Coverage for the expansion.
360   const FunctionRecord &Function;
361 
ExpansionRecordExpansionRecord362   ExpansionRecord(const CountedRegion &Region,
363                   const FunctionRecord &Function)
364       : FileID(Region.ExpandedFileID), Region(Region), Function(Function) {}
365 };
366 
367 /// \brief The execution count information starting at a point in a file.
368 ///
369 /// A sequence of CoverageSegments gives execution counts for a file in format
370 /// that's simple to iterate through for processing.
371 struct CoverageSegment {
372   /// \brief The line where this segment begins.
373   unsigned Line;
374   /// \brief The column where this segment begins.
375   unsigned Col;
376   /// \brief The execution count, or zero if no count was recorded.
377   uint64_t Count;
378   /// \brief When false, the segment was uninstrumented or skipped.
379   bool HasCount;
380   /// \brief Whether this enters a new region or returns to a previous count.
381   bool IsRegionEntry;
382 
CoverageSegmentCoverageSegment383   CoverageSegment(unsigned Line, unsigned Col, bool IsRegionEntry)
384       : Line(Line), Col(Col), Count(0), HasCount(false),
385         IsRegionEntry(IsRegionEntry) {}
386 
CoverageSegmentCoverageSegment387   CoverageSegment(unsigned Line, unsigned Col, uint64_t Count,
388                   bool IsRegionEntry)
389       : Line(Line), Col(Col), Count(Count), HasCount(true),
390         IsRegionEntry(IsRegionEntry) {}
391 
392   friend bool operator==(const CoverageSegment &L, const CoverageSegment &R) {
393     return std::tie(L.Line, L.Col, L.Count, L.HasCount, L.IsRegionEntry) ==
394            std::tie(R.Line, R.Col, R.Count, R.HasCount, R.IsRegionEntry);
395   }
396 };
397 
398 /// \brief Coverage information to be processed or displayed.
399 ///
400 /// This represents the coverage of an entire file, expansion, or function. It
401 /// provides a sequence of CoverageSegments to iterate through, as well as the
402 /// list of expansions that can be further processed.
403 class CoverageData {
404   std::string Filename;
405   std::vector<CoverageSegment> Segments;
406   std::vector<ExpansionRecord> Expansions;
407   friend class CoverageMapping;
408 
409 public:
CoverageData()410   CoverageData() {}
411 
CoverageData(StringRef Filename)412   CoverageData(StringRef Filename) : Filename(Filename) {}
413 
CoverageData(CoverageData && RHS)414   CoverageData(CoverageData &&RHS)
415       : Filename(std::move(RHS.Filename)), Segments(std::move(RHS.Segments)),
416         Expansions(std::move(RHS.Expansions)) {}
417 
418   /// \brief Get the name of the file this data covers.
getFilename()419   StringRef getFilename() const { return Filename; }
420 
begin()421   std::vector<CoverageSegment>::iterator begin() { return Segments.begin(); }
end()422   std::vector<CoverageSegment>::iterator end() { return Segments.end(); }
empty()423   bool empty() { return Segments.empty(); }
424 
425   /// \brief Expansions that can be further processed.
getExpansions()426   ArrayRef<ExpansionRecord> getExpansions() { return Expansions; }
427 };
428 
429 /// \brief The mapping of profile information to coverage data.
430 ///
431 /// This is the main interface to get coverage information, using a profile to
432 /// fill out execution counts.
433 class CoverageMapping {
434   std::vector<FunctionRecord> Functions;
435   unsigned MismatchedFunctionCount;
436 
CoverageMapping()437   CoverageMapping() : MismatchedFunctionCount(0) {}
438 
439 public:
440   /// \brief Load the coverage mapping using the given readers.
441   static Expected<std::unique_ptr<CoverageMapping>>
442   load(CoverageMappingReader &CoverageReader,
443        IndexedInstrProfReader &ProfileReader);
444 
445   /// \brief Load the coverage mapping from the given files.
446   static Expected<std::unique_ptr<CoverageMapping>>
447   load(StringRef ObjectFilename, StringRef ProfileFilename,
448        StringRef Arch = StringRef());
449 
450   /// \brief The number of functions that couldn't have their profiles mapped.
451   ///
452   /// This is a count of functions whose profile is out of date or otherwise
453   /// can't be associated with any coverage information.
getMismatchedCount()454   unsigned getMismatchedCount() { return MismatchedFunctionCount; }
455 
456   /// \brief Returns the list of files that are covered.
457   std::vector<StringRef> getUniqueSourceFiles() const;
458 
459   /// \brief Get the coverage for a particular file.
460   ///
461   /// The given filename must be the name as recorded in the coverage
462   /// information. That is, only names returned from getUniqueSourceFiles will
463   /// yield a result.
464   CoverageData getCoverageForFile(StringRef Filename) const;
465 
466   /// \brief Gets all of the functions covered by this profile.
getCoveredFunctions()467   iterator_range<FunctionRecordIterator> getCoveredFunctions() const {
468     return make_range(FunctionRecordIterator(Functions),
469                       FunctionRecordIterator());
470   }
471 
472   /// \brief Gets all of the functions in a particular file.
473   iterator_range<FunctionRecordIterator>
getCoveredFunctions(StringRef Filename)474   getCoveredFunctions(StringRef Filename) const {
475     return make_range(FunctionRecordIterator(Functions, Filename),
476                       FunctionRecordIterator());
477   }
478 
479   /// \brief Get the list of function instantiations in the file.
480   ///
481   /// Functions that are instantiated more than once, such as C++ template
482   /// specializations, have distinct coverage records for each instantiation.
483   std::vector<const FunctionRecord *> getInstantiations(StringRef Filename);
484 
485   /// \brief Get the coverage for a particular function.
486   CoverageData getCoverageForFunction(const FunctionRecord &Function);
487 
488   /// \brief Get the coverage for an expansion within a coverage set.
489   CoverageData getCoverageForExpansion(const ExpansionRecord &Expansion);
490 };
491 
492 // Profile coverage map has the following layout:
493 // [CoverageMapFileHeader]
494 // [ArrayStart]
495 //  [CovMapFunctionRecord]
496 //  [CovMapFunctionRecord]
497 //  ...
498 // [ArrayEnd]
499 // [Encoded Region Mapping Data]
500 LLVM_PACKED_START
501 template <class IntPtrT> struct CovMapFunctionRecordV1 {
502 #define COVMAP_V1
503 #define COVMAP_FUNC_RECORD(Type, LLVMType, Name, Init) Type Name;
504 #include "llvm/ProfileData/InstrProfData.inc"
505 #undef COVMAP_V1
506 
507   // Return the structural hash associated with the function.
getFuncHashCovMapFunctionRecordV1508   template <support::endianness Endian> uint64_t getFuncHash() const {
509     return support::endian::byte_swap<uint64_t, Endian>(FuncHash);
510   }
511   // Return the coverage map data size for the funciton.
getDataSizeCovMapFunctionRecordV1512   template <support::endianness Endian> uint32_t getDataSize() const {
513     return support::endian::byte_swap<uint32_t, Endian>(DataSize);
514   }
515   // Return function lookup key. The value is consider opaque.
getFuncNameRefCovMapFunctionRecordV1516   template <support::endianness Endian> IntPtrT getFuncNameRef() const {
517     return support::endian::byte_swap<IntPtrT, Endian>(NamePtr);
518   }
519   // Return the PGO name of the function */
520   template <support::endianness Endian>
getFuncNameCovMapFunctionRecordV1521   Error getFuncName(InstrProfSymtab &ProfileNames, StringRef &FuncName) const {
522     IntPtrT NameRef = getFuncNameRef<Endian>();
523     uint32_t NameS = support::endian::byte_swap<uint32_t, Endian>(NameSize);
524     FuncName = ProfileNames.getFuncName(NameRef, NameS);
525     if (NameS && FuncName.empty())
526       return make_error<CoverageMapError>(coveragemap_error::malformed);
527     return Error::success();
528   }
529 };
530 
531 struct CovMapFunctionRecord {
532 #define COVMAP_FUNC_RECORD(Type, LLVMType, Name, Init) Type Name;
533 #include "llvm/ProfileData/InstrProfData.inc"
534 
535   // Return the structural hash associated with the function.
getFuncHashCovMapFunctionRecord536   template <support::endianness Endian> uint64_t getFuncHash() const {
537     return support::endian::byte_swap<uint64_t, Endian>(FuncHash);
538   }
539   // Return the coverage map data size for the funciton.
getDataSizeCovMapFunctionRecord540   template <support::endianness Endian> uint32_t getDataSize() const {
541     return support::endian::byte_swap<uint32_t, Endian>(DataSize);
542   }
543   // Return function lookup key. The value is consider opaque.
getFuncNameRefCovMapFunctionRecord544   template <support::endianness Endian> uint64_t getFuncNameRef() const {
545     return support::endian::byte_swap<uint64_t, Endian>(NameRef);
546   }
547   // Return the PGO name of the function */
548   template <support::endianness Endian>
getFuncNameCovMapFunctionRecord549   Error getFuncName(InstrProfSymtab &ProfileNames, StringRef &FuncName) const {
550     uint64_t NameRef = getFuncNameRef<Endian>();
551     FuncName = ProfileNames.getFuncName(NameRef);
552     return Error::success();
553   }
554 };
555 
556 // Per module coverage mapping data header, i.e. CoverageMapFileHeader
557 // documented above.
558 struct CovMapHeader {
559 #define COVMAP_HEADER(Type, LLVMType, Name, Init) Type Name;
560 #include "llvm/ProfileData/InstrProfData.inc"
getNRecordsCovMapHeader561   template <support::endianness Endian> uint32_t getNRecords() const {
562     return support::endian::byte_swap<uint32_t, Endian>(NRecords);
563   }
getFilenamesSizeCovMapHeader564   template <support::endianness Endian> uint32_t getFilenamesSize() const {
565     return support::endian::byte_swap<uint32_t, Endian>(FilenamesSize);
566   }
getCoverageSizeCovMapHeader567   template <support::endianness Endian> uint32_t getCoverageSize() const {
568     return support::endian::byte_swap<uint32_t, Endian>(CoverageSize);
569   }
getVersionCovMapHeader570   template <support::endianness Endian> uint32_t getVersion() const {
571     return support::endian::byte_swap<uint32_t, Endian>(Version);
572   }
573 };
574 
575 LLVM_PACKED_END
576 
577 enum CovMapVersion {
578   Version1 = 0,
579   // Function's name reference from CovMapFuncRecord is changed from raw
580   // name string pointer to MD5 to support name section compression. Name
581   // section is also compressed.
582   Version2 = 1,
583   // The current version is Version2
584   CurrentVersion = INSTR_PROF_COVMAP_VERSION
585 };
586 
587 template <int CovMapVersion, class IntPtrT> struct CovMapTraits {
588   typedef CovMapFunctionRecord CovMapFuncRecordType;
589   typedef uint64_t NameRefType;
590 };
591 
592 template <class IntPtrT> struct CovMapTraits<CovMapVersion::Version1, IntPtrT> {
593   typedef CovMapFunctionRecordV1<IntPtrT> CovMapFuncRecordType;
594   typedef IntPtrT NameRefType;
595 };
596 
597 } // end namespace coverage
598 
599 /// \brief Provide DenseMapInfo for CounterExpression
600 template<> struct DenseMapInfo<coverage::CounterExpression> {
601   static inline coverage::CounterExpression getEmptyKey() {
602     using namespace coverage;
603     return CounterExpression(CounterExpression::ExprKind::Subtract,
604                              Counter::getCounter(~0U),
605                              Counter::getCounter(~0U));
606   }
607 
608   static inline coverage::CounterExpression getTombstoneKey() {
609     using namespace coverage;
610     return CounterExpression(CounterExpression::ExprKind::Add,
611                              Counter::getCounter(~0U),
612                              Counter::getCounter(~0U));
613   }
614 
615   static unsigned getHashValue(const coverage::CounterExpression &V) {
616     return static_cast<unsigned>(
617         hash_combine(V.Kind, V.LHS.getKind(), V.LHS.getCounterID(),
618                      V.RHS.getKind(), V.RHS.getCounterID()));
619   }
620 
621   static bool isEqual(const coverage::CounterExpression &LHS,
622                       const coverage::CounterExpression &RHS) {
623     return LHS.Kind == RHS.Kind && LHS.LHS == RHS.LHS && LHS.RHS == RHS.RHS;
624   }
625 };
626 
627 } // end namespace llvm
628 
629 #endif // LLVM_PROFILEDATA_COVERAGEMAPPING_H_
630