1 //=-- CoverageMapping.cpp - 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 // This file contains support for clang's and llvm's instrumentation based
11 // code coverage.
12 //
13 //===----------------------------------------------------------------------===//
14
15 #include "llvm/ProfileData/CoverageMapping.h"
16 #include "llvm/ADT/DenseMap.h"
17 #include "llvm/ADT/Optional.h"
18 #include "llvm/ADT/SmallBitVector.h"
19 #include "llvm/ProfileData/CoverageMappingReader.h"
20 #include "llvm/ProfileData/InstrProfReader.h"
21 #include "llvm/Support/Debug.h"
22 #include "llvm/Support/Errc.h"
23 #include "llvm/Support/ErrorHandling.h"
24 #include "llvm/Support/ManagedStatic.h"
25 #include "llvm/Support/Path.h"
26 #include "llvm/Support/raw_ostream.h"
27
28 using namespace llvm;
29 using namespace coverage;
30
31 #define DEBUG_TYPE "coverage-mapping"
32
get(const CounterExpression & E)33 Counter CounterExpressionBuilder::get(const CounterExpression &E) {
34 auto It = ExpressionIndices.find(E);
35 if (It != ExpressionIndices.end())
36 return Counter::getExpression(It->second);
37 unsigned I = Expressions.size();
38 Expressions.push_back(E);
39 ExpressionIndices[E] = I;
40 return Counter::getExpression(I);
41 }
42
extractTerms(Counter C,int Sign,SmallVectorImpl<std::pair<unsigned,int>> & Terms)43 void CounterExpressionBuilder::extractTerms(
44 Counter C, int Sign, SmallVectorImpl<std::pair<unsigned, int>> &Terms) {
45 switch (C.getKind()) {
46 case Counter::Zero:
47 break;
48 case Counter::CounterValueReference:
49 Terms.push_back(std::make_pair(C.getCounterID(), Sign));
50 break;
51 case Counter::Expression:
52 const auto &E = Expressions[C.getExpressionID()];
53 extractTerms(E.LHS, Sign, Terms);
54 extractTerms(E.RHS, E.Kind == CounterExpression::Subtract ? -Sign : Sign,
55 Terms);
56 break;
57 }
58 }
59
simplify(Counter ExpressionTree)60 Counter CounterExpressionBuilder::simplify(Counter ExpressionTree) {
61 // Gather constant terms.
62 llvm::SmallVector<std::pair<unsigned, int>, 32> Terms;
63 extractTerms(ExpressionTree, +1, Terms);
64
65 // If there are no terms, this is just a zero. The algorithm below assumes at
66 // least one term.
67 if (Terms.size() == 0)
68 return Counter::getZero();
69
70 // Group the terms by counter ID.
71 std::sort(Terms.begin(), Terms.end(),
72 [](const std::pair<unsigned, int> &LHS,
73 const std::pair<unsigned, int> &RHS) {
74 return LHS.first < RHS.first;
75 });
76
77 // Combine terms by counter ID to eliminate counters that sum to zero.
78 auto Prev = Terms.begin();
79 for (auto I = Prev + 1, E = Terms.end(); I != E; ++I) {
80 if (I->first == Prev->first) {
81 Prev->second += I->second;
82 continue;
83 }
84 ++Prev;
85 *Prev = *I;
86 }
87 Terms.erase(++Prev, Terms.end());
88
89 Counter C;
90 // Create additions. We do this before subtractions to avoid constructs like
91 // ((0 - X) + Y), as opposed to (Y - X).
92 for (auto Term : Terms) {
93 if (Term.second <= 0)
94 continue;
95 for (int I = 0; I < Term.second; ++I)
96 if (C.isZero())
97 C = Counter::getCounter(Term.first);
98 else
99 C = get(CounterExpression(CounterExpression::Add, C,
100 Counter::getCounter(Term.first)));
101 }
102
103 // Create subtractions.
104 for (auto Term : Terms) {
105 if (Term.second >= 0)
106 continue;
107 for (int I = 0; I < -Term.second; ++I)
108 C = get(CounterExpression(CounterExpression::Subtract, C,
109 Counter::getCounter(Term.first)));
110 }
111 return C;
112 }
113
add(Counter LHS,Counter RHS)114 Counter CounterExpressionBuilder::add(Counter LHS, Counter RHS) {
115 return simplify(get(CounterExpression(CounterExpression::Add, LHS, RHS)));
116 }
117
subtract(Counter LHS,Counter RHS)118 Counter CounterExpressionBuilder::subtract(Counter LHS, Counter RHS) {
119 return simplify(
120 get(CounterExpression(CounterExpression::Subtract, LHS, RHS)));
121 }
122
dump(const Counter & C,llvm::raw_ostream & OS) const123 void CounterMappingContext::dump(const Counter &C,
124 llvm::raw_ostream &OS) const {
125 switch (C.getKind()) {
126 case Counter::Zero:
127 OS << '0';
128 return;
129 case Counter::CounterValueReference:
130 OS << '#' << C.getCounterID();
131 break;
132 case Counter::Expression: {
133 if (C.getExpressionID() >= Expressions.size())
134 return;
135 const auto &E = Expressions[C.getExpressionID()];
136 OS << '(';
137 dump(E.LHS, OS);
138 OS << (E.Kind == CounterExpression::Subtract ? " - " : " + ");
139 dump(E.RHS, OS);
140 OS << ')';
141 break;
142 }
143 }
144 if (CounterValues.empty())
145 return;
146 ErrorOr<int64_t> Value = evaluate(C);
147 if (!Value)
148 return;
149 OS << '[' << *Value << ']';
150 }
151
evaluate(const Counter & C) const152 ErrorOr<int64_t> CounterMappingContext::evaluate(const Counter &C) const {
153 switch (C.getKind()) {
154 case Counter::Zero:
155 return 0;
156 case Counter::CounterValueReference:
157 if (C.getCounterID() >= CounterValues.size())
158 return make_error_code(errc::argument_out_of_domain);
159 return CounterValues[C.getCounterID()];
160 case Counter::Expression: {
161 if (C.getExpressionID() >= Expressions.size())
162 return make_error_code(errc::argument_out_of_domain);
163 const auto &E = Expressions[C.getExpressionID()];
164 ErrorOr<int64_t> LHS = evaluate(E.LHS);
165 if (!LHS)
166 return LHS;
167 ErrorOr<int64_t> RHS = evaluate(E.RHS);
168 if (!RHS)
169 return RHS;
170 return E.Kind == CounterExpression::Subtract ? *LHS - *RHS : *LHS + *RHS;
171 }
172 }
173 llvm_unreachable("Unhandled CounterKind");
174 }
175
skipOtherFiles()176 void FunctionRecordIterator::skipOtherFiles() {
177 while (Current != Records.end() && !Filename.empty() &&
178 Filename != Current->Filenames[0])
179 ++Current;
180 if (Current == Records.end())
181 *this = FunctionRecordIterator();
182 }
183
184 ErrorOr<std::unique_ptr<CoverageMapping>>
load(CoverageMappingReader & CoverageReader,IndexedInstrProfReader & ProfileReader)185 CoverageMapping::load(CoverageMappingReader &CoverageReader,
186 IndexedInstrProfReader &ProfileReader) {
187 auto Coverage = std::unique_ptr<CoverageMapping>(new CoverageMapping());
188
189 std::vector<uint64_t> Counts;
190 for (const auto &Record : CoverageReader) {
191 CounterMappingContext Ctx(Record.Expressions);
192
193 Counts.clear();
194 if (std::error_code EC = ProfileReader.getFunctionCounts(
195 Record.FunctionName, Record.FunctionHash, Counts)) {
196 if (EC == instrprof_error::hash_mismatch) {
197 Coverage->MismatchedFunctionCount++;
198 continue;
199 } else if (EC != instrprof_error::unknown_function)
200 return EC;
201 Counts.assign(Record.MappingRegions.size(), 0);
202 }
203 Ctx.setCounts(Counts);
204
205 assert(!Record.MappingRegions.empty() && "Function has no regions");
206
207 StringRef OrigFuncName = Record.FunctionName;
208 if (!Record.Filenames.empty())
209 OrigFuncName =
210 getFuncNameWithoutPrefix(OrigFuncName, Record.Filenames[0]);
211 FunctionRecord Function(OrigFuncName, Record.Filenames);
212 for (const auto &Region : Record.MappingRegions) {
213 ErrorOr<int64_t> ExecutionCount = Ctx.evaluate(Region.Count);
214 if (!ExecutionCount)
215 break;
216 Function.pushRegion(Region, *ExecutionCount);
217 }
218 if (Function.CountedRegions.size() != Record.MappingRegions.size()) {
219 Coverage->MismatchedFunctionCount++;
220 continue;
221 }
222
223 Coverage->Functions.push_back(std::move(Function));
224 }
225
226 return std::move(Coverage);
227 }
228
229 ErrorOr<std::unique_ptr<CoverageMapping>>
load(StringRef ObjectFilename,StringRef ProfileFilename,StringRef Arch)230 CoverageMapping::load(StringRef ObjectFilename, StringRef ProfileFilename,
231 StringRef Arch) {
232 auto CounterMappingBuff = MemoryBuffer::getFileOrSTDIN(ObjectFilename);
233 if (std::error_code EC = CounterMappingBuff.getError())
234 return EC;
235 auto CoverageReaderOrErr =
236 BinaryCoverageReader::create(CounterMappingBuff.get(), Arch);
237 if (std::error_code EC = CoverageReaderOrErr.getError())
238 return EC;
239 auto CoverageReader = std::move(CoverageReaderOrErr.get());
240 auto ProfileReaderOrErr = IndexedInstrProfReader::create(ProfileFilename);
241 if (auto EC = ProfileReaderOrErr.getError())
242 return EC;
243 auto ProfileReader = std::move(ProfileReaderOrErr.get());
244 return load(*CoverageReader, *ProfileReader);
245 }
246
247 namespace {
248 /// \brief Distributes functions into instantiation sets.
249 ///
250 /// An instantiation set is a collection of functions that have the same source
251 /// code, ie, template functions specializations.
252 class FunctionInstantiationSetCollector {
253 typedef DenseMap<std::pair<unsigned, unsigned>,
254 std::vector<const FunctionRecord *>> MapT;
255 MapT InstantiatedFunctions;
256
257 public:
insert(const FunctionRecord & Function,unsigned FileID)258 void insert(const FunctionRecord &Function, unsigned FileID) {
259 auto I = Function.CountedRegions.begin(), E = Function.CountedRegions.end();
260 while (I != E && I->FileID != FileID)
261 ++I;
262 assert(I != E && "function does not cover the given file");
263 auto &Functions = InstantiatedFunctions[I->startLoc()];
264 Functions.push_back(&Function);
265 }
266
begin()267 MapT::iterator begin() { return InstantiatedFunctions.begin(); }
268
end()269 MapT::iterator end() { return InstantiatedFunctions.end(); }
270 };
271
272 class SegmentBuilder {
273 std::vector<CoverageSegment> Segments;
274 SmallVector<const CountedRegion *, 8> ActiveRegions;
275
276 /// Start a segment with no count specified.
startSegment(unsigned Line,unsigned Col)277 void startSegment(unsigned Line, unsigned Col) {
278 DEBUG(dbgs() << "Top level segment at " << Line << ":" << Col << "\n");
279 Segments.emplace_back(Line, Col, /*IsRegionEntry=*/false);
280 }
281
282 /// Start a segment with the given Region's count.
startSegment(unsigned Line,unsigned Col,bool IsRegionEntry,const CountedRegion & Region)283 void startSegment(unsigned Line, unsigned Col, bool IsRegionEntry,
284 const CountedRegion &Region) {
285 if (Segments.empty())
286 Segments.emplace_back(Line, Col, IsRegionEntry);
287 CoverageSegment S = Segments.back();
288 // Avoid creating empty regions.
289 if (S.Line != Line || S.Col != Col) {
290 Segments.emplace_back(Line, Col, IsRegionEntry);
291 S = Segments.back();
292 }
293 DEBUG(dbgs() << "Segment at " << Line << ":" << Col);
294 // Set this region's count.
295 if (Region.Kind != coverage::CounterMappingRegion::SkippedRegion) {
296 DEBUG(dbgs() << " with count " << Region.ExecutionCount);
297 Segments.back().setCount(Region.ExecutionCount);
298 }
299 DEBUG(dbgs() << "\n");
300 }
301
302 /// Start a segment for the given region.
startSegment(const CountedRegion & Region)303 void startSegment(const CountedRegion &Region) {
304 startSegment(Region.LineStart, Region.ColumnStart, true, Region);
305 }
306
307 /// Pop the top region off of the active stack, starting a new segment with
308 /// the containing Region's count.
popRegion()309 void popRegion() {
310 const CountedRegion *Active = ActiveRegions.back();
311 unsigned Line = Active->LineEnd, Col = Active->ColumnEnd;
312 ActiveRegions.pop_back();
313 if (ActiveRegions.empty())
314 startSegment(Line, Col);
315 else
316 startSegment(Line, Col, false, *ActiveRegions.back());
317 }
318
319 public:
320 /// Build a list of CoverageSegments from a sorted list of Regions.
buildSegments(ArrayRef<CountedRegion> Regions)321 std::vector<CoverageSegment> buildSegments(ArrayRef<CountedRegion> Regions) {
322 const CountedRegion *PrevRegion = nullptr;
323 for (const auto &Region : Regions) {
324 // Pop any regions that end before this one starts.
325 while (!ActiveRegions.empty() &&
326 ActiveRegions.back()->endLoc() <= Region.startLoc())
327 popRegion();
328 if (PrevRegion && PrevRegion->startLoc() == Region.startLoc() &&
329 PrevRegion->endLoc() == Region.endLoc()) {
330 if (Region.Kind == coverage::CounterMappingRegion::CodeRegion)
331 Segments.back().addCount(Region.ExecutionCount);
332 } else {
333 // Add this region to the stack.
334 ActiveRegions.push_back(&Region);
335 startSegment(Region);
336 }
337 PrevRegion = &Region;
338 }
339 // Pop any regions that are left in the stack.
340 while (!ActiveRegions.empty())
341 popRegion();
342 return Segments;
343 }
344 };
345 }
346
getUniqueSourceFiles() const347 std::vector<StringRef> CoverageMapping::getUniqueSourceFiles() const {
348 std::vector<StringRef> Filenames;
349 for (const auto &Function : getCoveredFunctions())
350 Filenames.insert(Filenames.end(), Function.Filenames.begin(),
351 Function.Filenames.end());
352 std::sort(Filenames.begin(), Filenames.end());
353 auto Last = std::unique(Filenames.begin(), Filenames.end());
354 Filenames.erase(Last, Filenames.end());
355 return Filenames;
356 }
357
gatherFileIDs(StringRef SourceFile,const FunctionRecord & Function)358 static SmallBitVector gatherFileIDs(StringRef SourceFile,
359 const FunctionRecord &Function) {
360 SmallBitVector FilenameEquivalence(Function.Filenames.size(), false);
361 for (unsigned I = 0, E = Function.Filenames.size(); I < E; ++I)
362 if (SourceFile == Function.Filenames[I])
363 FilenameEquivalence[I] = true;
364 return FilenameEquivalence;
365 }
366
findMainViewFileID(StringRef SourceFile,const FunctionRecord & Function)367 static Optional<unsigned> findMainViewFileID(StringRef SourceFile,
368 const FunctionRecord &Function) {
369 SmallBitVector IsNotExpandedFile(Function.Filenames.size(), true);
370 SmallBitVector FilenameEquivalence = gatherFileIDs(SourceFile, Function);
371 for (const auto &CR : Function.CountedRegions)
372 if (CR.Kind == CounterMappingRegion::ExpansionRegion &&
373 FilenameEquivalence[CR.FileID])
374 IsNotExpandedFile[CR.ExpandedFileID] = false;
375 IsNotExpandedFile &= FilenameEquivalence;
376 int I = IsNotExpandedFile.find_first();
377 if (I == -1)
378 return None;
379 return I;
380 }
381
findMainViewFileID(const FunctionRecord & Function)382 static Optional<unsigned> findMainViewFileID(const FunctionRecord &Function) {
383 SmallBitVector IsNotExpandedFile(Function.Filenames.size(), true);
384 for (const auto &CR : Function.CountedRegions)
385 if (CR.Kind == CounterMappingRegion::ExpansionRegion)
386 IsNotExpandedFile[CR.ExpandedFileID] = false;
387 int I = IsNotExpandedFile.find_first();
388 if (I == -1)
389 return None;
390 return I;
391 }
392
393 /// Sort a nested sequence of regions from a single file.
sortNestedRegions(It First,It Last)394 template <class It> static void sortNestedRegions(It First, It Last) {
395 std::sort(First, Last,
396 [](const CountedRegion &LHS, const CountedRegion &RHS) {
397 if (LHS.startLoc() == RHS.startLoc())
398 // When LHS completely contains RHS, we sort LHS first.
399 return RHS.endLoc() < LHS.endLoc();
400 return LHS.startLoc() < RHS.startLoc();
401 });
402 }
403
isExpansion(const CountedRegion & R,unsigned FileID)404 static bool isExpansion(const CountedRegion &R, unsigned FileID) {
405 return R.Kind == CounterMappingRegion::ExpansionRegion && R.FileID == FileID;
406 }
407
getCoverageForFile(StringRef Filename)408 CoverageData CoverageMapping::getCoverageForFile(StringRef Filename) {
409 CoverageData FileCoverage(Filename);
410 std::vector<coverage::CountedRegion> Regions;
411
412 for (const auto &Function : Functions) {
413 auto MainFileID = findMainViewFileID(Filename, Function);
414 if (!MainFileID)
415 continue;
416 auto FileIDs = gatherFileIDs(Filename, Function);
417 for (const auto &CR : Function.CountedRegions)
418 if (FileIDs.test(CR.FileID)) {
419 Regions.push_back(CR);
420 if (isExpansion(CR, *MainFileID))
421 FileCoverage.Expansions.emplace_back(CR, Function);
422 }
423 }
424
425 sortNestedRegions(Regions.begin(), Regions.end());
426 DEBUG(dbgs() << "Emitting segments for file: " << Filename << "\n");
427 FileCoverage.Segments = SegmentBuilder().buildSegments(Regions);
428
429 return FileCoverage;
430 }
431
432 std::vector<const FunctionRecord *>
getInstantiations(StringRef Filename)433 CoverageMapping::getInstantiations(StringRef Filename) {
434 FunctionInstantiationSetCollector InstantiationSetCollector;
435 for (const auto &Function : Functions) {
436 auto MainFileID = findMainViewFileID(Filename, Function);
437 if (!MainFileID)
438 continue;
439 InstantiationSetCollector.insert(Function, *MainFileID);
440 }
441
442 std::vector<const FunctionRecord *> Result;
443 for (const auto &InstantiationSet : InstantiationSetCollector) {
444 if (InstantiationSet.second.size() < 2)
445 continue;
446 Result.insert(Result.end(), InstantiationSet.second.begin(),
447 InstantiationSet.second.end());
448 }
449 return Result;
450 }
451
452 CoverageData
getCoverageForFunction(const FunctionRecord & Function)453 CoverageMapping::getCoverageForFunction(const FunctionRecord &Function) {
454 auto MainFileID = findMainViewFileID(Function);
455 if (!MainFileID)
456 return CoverageData();
457
458 CoverageData FunctionCoverage(Function.Filenames[*MainFileID]);
459 std::vector<coverage::CountedRegion> Regions;
460 for (const auto &CR : Function.CountedRegions)
461 if (CR.FileID == *MainFileID) {
462 Regions.push_back(CR);
463 if (isExpansion(CR, *MainFileID))
464 FunctionCoverage.Expansions.emplace_back(CR, Function);
465 }
466
467 sortNestedRegions(Regions.begin(), Regions.end());
468 DEBUG(dbgs() << "Emitting segments for function: " << Function.Name << "\n");
469 FunctionCoverage.Segments = SegmentBuilder().buildSegments(Regions);
470
471 return FunctionCoverage;
472 }
473
474 CoverageData
getCoverageForExpansion(const ExpansionRecord & Expansion)475 CoverageMapping::getCoverageForExpansion(const ExpansionRecord &Expansion) {
476 CoverageData ExpansionCoverage(
477 Expansion.Function.Filenames[Expansion.FileID]);
478 std::vector<coverage::CountedRegion> Regions;
479 for (const auto &CR : Expansion.Function.CountedRegions)
480 if (CR.FileID == Expansion.FileID) {
481 Regions.push_back(CR);
482 if (isExpansion(CR, Expansion.FileID))
483 ExpansionCoverage.Expansions.emplace_back(CR, Expansion.Function);
484 }
485
486 sortNestedRegions(Regions.begin(), Regions.end());
487 DEBUG(dbgs() << "Emitting segments for expansion of file " << Expansion.FileID
488 << "\n");
489 ExpansionCoverage.Segments = SegmentBuilder().buildSegments(Regions);
490
491 return ExpansionCoverage;
492 }
493
494 namespace {
495 class CoverageMappingErrorCategoryType : public std::error_category {
name() const496 const char *name() const LLVM_NOEXCEPT override { return "llvm.coveragemap"; }
message(int IE) const497 std::string message(int IE) const override {
498 auto E = static_cast<coveragemap_error>(IE);
499 switch (E) {
500 case coveragemap_error::success:
501 return "Success";
502 case coveragemap_error::eof:
503 return "End of File";
504 case coveragemap_error::no_data_found:
505 return "No coverage data found";
506 case coveragemap_error::unsupported_version:
507 return "Unsupported coverage format version";
508 case coveragemap_error::truncated:
509 return "Truncated coverage data";
510 case coveragemap_error::malformed:
511 return "Malformed coverage data";
512 }
513 llvm_unreachable("A value of coveragemap_error has no message.");
514 }
515 };
516 }
517
518 static ManagedStatic<CoverageMappingErrorCategoryType> ErrorCategory;
519
coveragemap_category()520 const std::error_category &llvm::coveragemap_category() {
521 return *ErrorCategory;
522 }
523