//===--- CoverageMappingGen.cpp - Coverage mapping generation ---*- C++ -*-===// // // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. // See https://llvm.org/LICENSE.txt for license information. // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception // //===----------------------------------------------------------------------===// // // Instrumentation-based code coverage mapping generator // //===----------------------------------------------------------------------===// #include "CoverageMappingGen.h" #include "CodeGenFunction.h" #include "clang/AST/StmtVisitor.h" #include "clang/Basic/Diagnostic.h" #include "clang/Basic/FileManager.h" #include "clang/Frontend/FrontendDiagnostic.h" #include "clang/Lex/Lexer.h" #include "llvm/ADT/SmallSet.h" #include "llvm/ADT/StringExtras.h" #include "llvm/ProfileData/Coverage/CoverageMapping.h" #include "llvm/ProfileData/Coverage/CoverageMappingReader.h" #include "llvm/ProfileData/Coverage/CoverageMappingWriter.h" #include "llvm/ProfileData/InstrProfReader.h" #include "llvm/Support/FileSystem.h" #include "llvm/Support/Path.h" #include // This selects the coverage mapping format defined when `InstrProfData.inc` // is textually included. #define COVMAP_V3 static llvm::cl::opt EmptyLineCommentCoverage( "emptyline-comment-coverage", llvm::cl::desc("Emit emptylines and comment lines as skipped regions (only " "disable it on test)"), llvm::cl::init(true), llvm::cl::Hidden); static llvm::cl::opt SystemHeadersCoverage( "system-headers-coverage", llvm::cl::desc("Enable collecting coverage from system headers"), llvm::cl::init(false), llvm::cl::Hidden); using namespace clang; using namespace CodeGen; using namespace llvm::coverage; CoverageSourceInfo * CoverageMappingModuleGen::setUpCoverageCallbacks(Preprocessor &PP) { CoverageSourceInfo *CoverageInfo = new CoverageSourceInfo(PP.getSourceManager()); PP.addPPCallbacks(std::unique_ptr(CoverageInfo)); if (EmptyLineCommentCoverage) { PP.addCommentHandler(CoverageInfo); PP.setEmptylineHandler(CoverageInfo); PP.setPreprocessToken(true); PP.setTokenWatcher([CoverageInfo](clang::Token Tok) { // Update previous token location. CoverageInfo->PrevTokLoc = Tok.getLocation(); if (Tok.getKind() != clang::tok::eod) CoverageInfo->updateNextTokLoc(Tok.getLocation()); }); } return CoverageInfo; } void CoverageSourceInfo::AddSkippedRange(SourceRange Range, SkippedRange::Kind RangeKind) { if (EmptyLineCommentCoverage && !SkippedRanges.empty() && PrevTokLoc == SkippedRanges.back().PrevTokLoc && SourceMgr.isWrittenInSameFile(SkippedRanges.back().Range.getEnd(), Range.getBegin())) SkippedRanges.back().Range.setEnd(Range.getEnd()); else SkippedRanges.push_back({Range, RangeKind, PrevTokLoc}); } void CoverageSourceInfo::SourceRangeSkipped(SourceRange Range, SourceLocation) { AddSkippedRange(Range, SkippedRange::PPIfElse); } void CoverageSourceInfo::HandleEmptyline(SourceRange Range) { AddSkippedRange(Range, SkippedRange::EmptyLine); } bool CoverageSourceInfo::HandleComment(Preprocessor &PP, SourceRange Range) { AddSkippedRange(Range, SkippedRange::Comment); return false; } void CoverageSourceInfo::updateNextTokLoc(SourceLocation Loc) { if (!SkippedRanges.empty() && SkippedRanges.back().NextTokLoc.isInvalid()) SkippedRanges.back().NextTokLoc = Loc; } namespace { /// A region of source code that can be mapped to a counter. class SourceMappingRegion { /// Primary Counter that is also used for Branch Regions for "True" branches. Counter Count; /// Secondary Counter used for Branch Regions for "False" branches. std::optional FalseCount; /// The region's starting location. std::optional LocStart; /// The region's ending location. std::optional LocEnd; /// Whether this region is a gap region. The count from a gap region is set /// as the line execution count if there are no other regions on the line. bool GapRegion; public: SourceMappingRegion(Counter Count, std::optional LocStart, std::optional LocEnd, bool GapRegion = false) : Count(Count), LocStart(LocStart), LocEnd(LocEnd), GapRegion(GapRegion) { } SourceMappingRegion(Counter Count, std::optional FalseCount, std::optional LocStart, std::optional LocEnd, bool GapRegion = false) : Count(Count), FalseCount(FalseCount), LocStart(LocStart), LocEnd(LocEnd), GapRegion(GapRegion) {} const Counter &getCounter() const { return Count; } const Counter &getFalseCounter() const { assert(FalseCount && "Region has no alternate counter"); return *FalseCount; } void setCounter(Counter C) { Count = C; } bool hasStartLoc() const { return LocStart.has_value(); } void setStartLoc(SourceLocation Loc) { LocStart = Loc; } SourceLocation getBeginLoc() const { assert(LocStart && "Region has no start location"); return *LocStart; } bool hasEndLoc() const { return LocEnd.has_value(); } void setEndLoc(SourceLocation Loc) { assert(Loc.isValid() && "Setting an invalid end location"); LocEnd = Loc; } SourceLocation getEndLoc() const { assert(LocEnd && "Region has no end location"); return *LocEnd; } bool isGap() const { return GapRegion; } void setGap(bool Gap) { GapRegion = Gap; } bool isBranch() const { return FalseCount.has_value(); } }; /// Spelling locations for the start and end of a source region. struct SpellingRegion { /// The line where the region starts. unsigned LineStart; /// The column where the region starts. unsigned ColumnStart; /// The line where the region ends. unsigned LineEnd; /// The column where the region ends. unsigned ColumnEnd; SpellingRegion(SourceManager &SM, SourceLocation LocStart, SourceLocation LocEnd) { LineStart = SM.getSpellingLineNumber(LocStart); ColumnStart = SM.getSpellingColumnNumber(LocStart); LineEnd = SM.getSpellingLineNumber(LocEnd); ColumnEnd = SM.getSpellingColumnNumber(LocEnd); } SpellingRegion(SourceManager &SM, SourceMappingRegion &R) : SpellingRegion(SM, R.getBeginLoc(), R.getEndLoc()) {} /// Check if the start and end locations appear in source order, i.e /// top->bottom, left->right. bool isInSourceOrder() const { return (LineStart < LineEnd) || (LineStart == LineEnd && ColumnStart <= ColumnEnd); } }; /// Provides the common functionality for the different /// coverage mapping region builders. class CoverageMappingBuilder { public: CoverageMappingModuleGen &CVM; SourceManager &SM; const LangOptions &LangOpts; private: /// Map of clang's FileIDs to IDs used for coverage mapping. llvm::SmallDenseMap, 8> FileIDMapping; public: /// The coverage mapping regions for this function llvm::SmallVector MappingRegions; /// The source mapping regions for this function. std::vector SourceRegions; /// A set of regions which can be used as a filter. /// /// It is produced by emitExpansionRegions() and is used in /// emitSourceRegions() to suppress producing code regions if /// the same area is covered by expansion regions. typedef llvm::SmallSet, 8> SourceRegionFilter; CoverageMappingBuilder(CoverageMappingModuleGen &CVM, SourceManager &SM, const LangOptions &LangOpts) : CVM(CVM), SM(SM), LangOpts(LangOpts) {} /// Return the precise end location for the given token. SourceLocation getPreciseTokenLocEnd(SourceLocation Loc) { // We avoid getLocForEndOfToken here, because it doesn't do what we want for // macro locations, which we just treat as expanded files. unsigned TokLen = Lexer::MeasureTokenLength(SM.getSpellingLoc(Loc), SM, LangOpts); return Loc.getLocWithOffset(TokLen); } /// Return the start location of an included file or expanded macro. SourceLocation getStartOfFileOrMacro(SourceLocation Loc) { if (Loc.isMacroID()) return Loc.getLocWithOffset(-SM.getFileOffset(Loc)); return SM.getLocForStartOfFile(SM.getFileID(Loc)); } /// Return the end location of an included file or expanded macro. SourceLocation getEndOfFileOrMacro(SourceLocation Loc) { if (Loc.isMacroID()) return Loc.getLocWithOffset(SM.getFileIDSize(SM.getFileID(Loc)) - SM.getFileOffset(Loc)); return SM.getLocForEndOfFile(SM.getFileID(Loc)); } /// Find out where the current file is included or macro is expanded. SourceLocation getIncludeOrExpansionLoc(SourceLocation Loc) { return Loc.isMacroID() ? SM.getImmediateExpansionRange(Loc).getBegin() : SM.getIncludeLoc(SM.getFileID(Loc)); } /// Return true if \c Loc is a location in a built-in macro. bool isInBuiltin(SourceLocation Loc) { return SM.getBufferName(SM.getSpellingLoc(Loc)) == ""; } /// Check whether \c Loc is included or expanded from \c Parent. bool isNestedIn(SourceLocation Loc, FileID Parent) { do { Loc = getIncludeOrExpansionLoc(Loc); if (Loc.isInvalid()) return false; } while (!SM.isInFileID(Loc, Parent)); return true; } /// Get the start of \c S ignoring macro arguments and builtin macros. SourceLocation getStart(const Stmt *S) { SourceLocation Loc = S->getBeginLoc(); while (SM.isMacroArgExpansion(Loc) || isInBuiltin(Loc)) Loc = SM.getImmediateExpansionRange(Loc).getBegin(); return Loc; } /// Get the end of \c S ignoring macro arguments and builtin macros. SourceLocation getEnd(const Stmt *S) { SourceLocation Loc = S->getEndLoc(); while (SM.isMacroArgExpansion(Loc) || isInBuiltin(Loc)) Loc = SM.getImmediateExpansionRange(Loc).getBegin(); return getPreciseTokenLocEnd(Loc); } /// Find the set of files we have regions for and assign IDs /// /// Fills \c Mapping with the virtual file mapping needed to write out /// coverage and collects the necessary file information to emit source and /// expansion regions. void gatherFileIDs(SmallVectorImpl &Mapping) { FileIDMapping.clear(); llvm::SmallSet Visited; SmallVector, 8> FileLocs; for (const auto &Region : SourceRegions) { SourceLocation Loc = Region.getBeginLoc(); FileID File = SM.getFileID(Loc); if (!Visited.insert(File).second) continue; // Do not map FileID's associated with system headers unless collecting // coverage from system headers is explicitly enabled. if (!SystemHeadersCoverage && SM.isInSystemHeader(SM.getSpellingLoc(Loc))) continue; unsigned Depth = 0; for (SourceLocation Parent = getIncludeOrExpansionLoc(Loc); Parent.isValid(); Parent = getIncludeOrExpansionLoc(Parent)) ++Depth; FileLocs.push_back(std::make_pair(Loc, Depth)); } llvm::stable_sort(FileLocs, llvm::less_second()); for (const auto &FL : FileLocs) { SourceLocation Loc = FL.first; FileID SpellingFile = SM.getDecomposedSpellingLoc(Loc).first; auto Entry = SM.getFileEntryRefForID(SpellingFile); if (!Entry) continue; FileIDMapping[SM.getFileID(Loc)] = std::make_pair(Mapping.size(), Loc); Mapping.push_back(CVM.getFileID(*Entry)); } } /// Get the coverage mapping file ID for \c Loc. /// /// If such file id doesn't exist, return std::nullopt. std::optional getCoverageFileID(SourceLocation Loc) { auto Mapping = FileIDMapping.find(SM.getFileID(Loc)); if (Mapping != FileIDMapping.end()) return Mapping->second.first; return std::nullopt; } /// This shrinks the skipped range if it spans a line that contains a /// non-comment token. If shrinking the skipped range would make it empty, /// this returns std::nullopt. /// Note this function can potentially be expensive because /// getSpellingLineNumber uses getLineNumber, which is expensive. std::optional adjustSkippedRange(SourceManager &SM, SourceLocation LocStart, SourceLocation LocEnd, SourceLocation PrevTokLoc, SourceLocation NextTokLoc) { SpellingRegion SR{SM, LocStart, LocEnd}; SR.ColumnStart = 1; if (PrevTokLoc.isValid() && SM.isWrittenInSameFile(LocStart, PrevTokLoc) && SR.LineStart == SM.getSpellingLineNumber(PrevTokLoc)) SR.LineStart++; if (NextTokLoc.isValid() && SM.isWrittenInSameFile(LocEnd, NextTokLoc) && SR.LineEnd == SM.getSpellingLineNumber(NextTokLoc)) { SR.LineEnd--; SR.ColumnEnd++; } if (SR.isInSourceOrder()) return SR; return std::nullopt; } /// Gather all the regions that were skipped by the preprocessor /// using the constructs like #if or comments. void gatherSkippedRegions() { /// An array of the minimum lineStarts and the maximum lineEnds /// for mapping regions from the appropriate source files. llvm::SmallVector, 8> FileLineRanges; FileLineRanges.resize( FileIDMapping.size(), std::make_pair(std::numeric_limits::max(), 0)); for (const auto &R : MappingRegions) { FileLineRanges[R.FileID].first = std::min(FileLineRanges[R.FileID].first, R.LineStart); FileLineRanges[R.FileID].second = std::max(FileLineRanges[R.FileID].second, R.LineEnd); } auto SkippedRanges = CVM.getSourceInfo().getSkippedRanges(); for (auto &I : SkippedRanges) { SourceRange Range = I.Range; auto LocStart = Range.getBegin(); auto LocEnd = Range.getEnd(); assert(SM.isWrittenInSameFile(LocStart, LocEnd) && "region spans multiple files"); auto CovFileID = getCoverageFileID(LocStart); if (!CovFileID) continue; std::optional SR; if (I.isComment()) SR = adjustSkippedRange(SM, LocStart, LocEnd, I.PrevTokLoc, I.NextTokLoc); else if (I.isPPIfElse() || I.isEmptyLine()) SR = {SM, LocStart, LocEnd}; if (!SR) continue; auto Region = CounterMappingRegion::makeSkipped( *CovFileID, SR->LineStart, SR->ColumnStart, SR->LineEnd, SR->ColumnEnd); // Make sure that we only collect the regions that are inside // the source code of this function. if (Region.LineStart >= FileLineRanges[*CovFileID].first && Region.LineEnd <= FileLineRanges[*CovFileID].second) MappingRegions.push_back(Region); } } /// Generate the coverage counter mapping regions from collected /// source regions. void emitSourceRegions(const SourceRegionFilter &Filter) { for (const auto &Region : SourceRegions) { assert(Region.hasEndLoc() && "incomplete region"); SourceLocation LocStart = Region.getBeginLoc(); assert(SM.getFileID(LocStart).isValid() && "region in invalid file"); // Ignore regions from system headers unless collecting coverage from // system headers is explicitly enabled. if (!SystemHeadersCoverage && SM.isInSystemHeader(SM.getSpellingLoc(LocStart))) continue; auto CovFileID = getCoverageFileID(LocStart); // Ignore regions that don't have a file, such as builtin macros. if (!CovFileID) continue; SourceLocation LocEnd = Region.getEndLoc(); assert(SM.isWrittenInSameFile(LocStart, LocEnd) && "region spans multiple files"); // Don't add code regions for the area covered by expansion regions. // This not only suppresses redundant regions, but sometimes prevents // creating regions with wrong counters if, for example, a statement's // body ends at the end of a nested macro. if (Filter.count(std::make_pair(LocStart, LocEnd))) continue; // Find the spelling locations for the mapping region. SpellingRegion SR{SM, LocStart, LocEnd}; assert(SR.isInSourceOrder() && "region start and end out of order"); if (Region.isGap()) { MappingRegions.push_back(CounterMappingRegion::makeGapRegion( Region.getCounter(), *CovFileID, SR.LineStart, SR.ColumnStart, SR.LineEnd, SR.ColumnEnd)); } else if (Region.isBranch()) { MappingRegions.push_back(CounterMappingRegion::makeBranchRegion( Region.getCounter(), Region.getFalseCounter(), *CovFileID, SR.LineStart, SR.ColumnStart, SR.LineEnd, SR.ColumnEnd)); } else { MappingRegions.push_back(CounterMappingRegion::makeRegion( Region.getCounter(), *CovFileID, SR.LineStart, SR.ColumnStart, SR.LineEnd, SR.ColumnEnd)); } } } /// Generate expansion regions for each virtual file we've seen. SourceRegionFilter emitExpansionRegions() { SourceRegionFilter Filter; for (const auto &FM : FileIDMapping) { SourceLocation ExpandedLoc = FM.second.second; SourceLocation ParentLoc = getIncludeOrExpansionLoc(ExpandedLoc); if (ParentLoc.isInvalid()) continue; auto ParentFileID = getCoverageFileID(ParentLoc); if (!ParentFileID) continue; auto ExpandedFileID = getCoverageFileID(ExpandedLoc); assert(ExpandedFileID && "expansion in uncovered file"); SourceLocation LocEnd = getPreciseTokenLocEnd(ParentLoc); assert(SM.isWrittenInSameFile(ParentLoc, LocEnd) && "region spans multiple files"); Filter.insert(std::make_pair(ParentLoc, LocEnd)); SpellingRegion SR{SM, ParentLoc, LocEnd}; assert(SR.isInSourceOrder() && "region start and end out of order"); MappingRegions.push_back(CounterMappingRegion::makeExpansion( *ParentFileID, *ExpandedFileID, SR.LineStart, SR.ColumnStart, SR.LineEnd, SR.ColumnEnd)); } return Filter; } }; /// Creates unreachable coverage regions for the functions that /// are not emitted. struct EmptyCoverageMappingBuilder : public CoverageMappingBuilder { EmptyCoverageMappingBuilder(CoverageMappingModuleGen &CVM, SourceManager &SM, const LangOptions &LangOpts) : CoverageMappingBuilder(CVM, SM, LangOpts) {} void VisitDecl(const Decl *D) { if (!D->hasBody()) return; auto Body = D->getBody(); SourceLocation Start = getStart(Body); SourceLocation End = getEnd(Body); if (!SM.isWrittenInSameFile(Start, End)) { // Walk up to find the common ancestor. // Correct the locations accordingly. FileID StartFileID = SM.getFileID(Start); FileID EndFileID = SM.getFileID(End); while (StartFileID != EndFileID && !isNestedIn(End, StartFileID)) { Start = getIncludeOrExpansionLoc(Start); assert(Start.isValid() && "Declaration start location not nested within a known region"); StartFileID = SM.getFileID(Start); } while (StartFileID != EndFileID) { End = getPreciseTokenLocEnd(getIncludeOrExpansionLoc(End)); assert(End.isValid() && "Declaration end location not nested within a known region"); EndFileID = SM.getFileID(End); } } SourceRegions.emplace_back(Counter(), Start, End); } /// Write the mapping data to the output stream void write(llvm::raw_ostream &OS) { SmallVector FileIDMapping; gatherFileIDs(FileIDMapping); emitSourceRegions(SourceRegionFilter()); if (MappingRegions.empty()) return; CoverageMappingWriter Writer(FileIDMapping, std::nullopt, MappingRegions); Writer.write(OS); } }; /// A StmtVisitor that creates coverage mapping regions which map /// from the source code locations to the PGO counters. struct CounterCoverageMappingBuilder : public CoverageMappingBuilder, public ConstStmtVisitor { /// The map of statements to count values. llvm::DenseMap &CounterMap; /// A stack of currently live regions. std::vector RegionStack; CounterExpressionBuilder Builder; /// A location in the most recently visited file or macro. /// /// This is used to adjust the active source regions appropriately when /// expressions cross file or macro boundaries. SourceLocation MostRecentLocation; /// Whether the visitor at a terminate statement. bool HasTerminateStmt = false; /// Gap region counter after terminate statement. Counter GapRegionCounter; /// Return a counter for the subtraction of \c RHS from \c LHS Counter subtractCounters(Counter LHS, Counter RHS, bool Simplify = true) { return Builder.subtract(LHS, RHS, Simplify); } /// Return a counter for the sum of \c LHS and \c RHS. Counter addCounters(Counter LHS, Counter RHS, bool Simplify = true) { return Builder.add(LHS, RHS, Simplify); } Counter addCounters(Counter C1, Counter C2, Counter C3, bool Simplify = true) { return addCounters(addCounters(C1, C2, Simplify), C3, Simplify); } /// Return the region counter for the given statement. /// /// This should only be called on statements that have a dedicated counter. Counter getRegionCounter(const Stmt *S) { return Counter::getCounter(CounterMap[S]); } /// Push a region onto the stack. /// /// Returns the index on the stack where the region was pushed. This can be /// used with popRegions to exit a "scope", ending the region that was pushed. size_t pushRegion(Counter Count, std::optional StartLoc = std::nullopt, std::optional EndLoc = std::nullopt, std::optional FalseCount = std::nullopt) { if (StartLoc && !FalseCount) { MostRecentLocation = *StartLoc; } // If either of these locations is invalid, something elsewhere in the // compiler has broken. assert((!StartLoc || StartLoc->isValid()) && "Start location is not valid"); assert((!EndLoc || EndLoc->isValid()) && "End location is not valid"); // However, we can still recover without crashing. // If either location is invalid, set it to std::nullopt to avoid // letting users of RegionStack think that region has a valid start/end // location. if (StartLoc && StartLoc->isInvalid()) StartLoc = std::nullopt; if (EndLoc && EndLoc->isInvalid()) EndLoc = std::nullopt; RegionStack.emplace_back(Count, FalseCount, StartLoc, EndLoc); return RegionStack.size() - 1; } size_t locationDepth(SourceLocation Loc) { size_t Depth = 0; while (Loc.isValid()) { Loc = getIncludeOrExpansionLoc(Loc); Depth++; } return Depth; } /// Pop regions from the stack into the function's list of regions. /// /// Adds all regions from \c ParentIndex to the top of the stack to the /// function's \c SourceRegions. void popRegions(size_t ParentIndex) { assert(RegionStack.size() >= ParentIndex && "parent not in stack"); while (RegionStack.size() > ParentIndex) { SourceMappingRegion &Region = RegionStack.back(); if (Region.hasStartLoc() && (Region.hasEndLoc() || RegionStack[ParentIndex].hasEndLoc())) { SourceLocation StartLoc = Region.getBeginLoc(); SourceLocation EndLoc = Region.hasEndLoc() ? Region.getEndLoc() : RegionStack[ParentIndex].getEndLoc(); bool isBranch = Region.isBranch(); size_t StartDepth = locationDepth(StartLoc); size_t EndDepth = locationDepth(EndLoc); while (!SM.isWrittenInSameFile(StartLoc, EndLoc)) { bool UnnestStart = StartDepth >= EndDepth; bool UnnestEnd = EndDepth >= StartDepth; if (UnnestEnd) { // The region ends in a nested file or macro expansion. If the // region is not a branch region, create a separate region for each // expansion, and for all regions, update the EndLoc. Branch // regions should not be split in order to keep a straightforward // correspondance between the region and its associated branch // condition, even if the condition spans multiple depths. SourceLocation NestedLoc = getStartOfFileOrMacro(EndLoc); assert(SM.isWrittenInSameFile(NestedLoc, EndLoc)); if (!isBranch && !isRegionAlreadyAdded(NestedLoc, EndLoc)) SourceRegions.emplace_back(Region.getCounter(), NestedLoc, EndLoc); EndLoc = getPreciseTokenLocEnd(getIncludeOrExpansionLoc(EndLoc)); if (EndLoc.isInvalid()) llvm::report_fatal_error( "File exit not handled before popRegions"); EndDepth--; } if (UnnestStart) { // The region ends in a nested file or macro expansion. If the // region is not a branch region, create a separate region for each // expansion, and for all regions, update the StartLoc. Branch // regions should not be split in order to keep a straightforward // correspondance between the region and its associated branch // condition, even if the condition spans multiple depths. SourceLocation NestedLoc = getEndOfFileOrMacro(StartLoc); assert(SM.isWrittenInSameFile(StartLoc, NestedLoc)); if (!isBranch && !isRegionAlreadyAdded(StartLoc, NestedLoc)) SourceRegions.emplace_back(Region.getCounter(), StartLoc, NestedLoc); StartLoc = getIncludeOrExpansionLoc(StartLoc); if (StartLoc.isInvalid()) llvm::report_fatal_error( "File exit not handled before popRegions"); StartDepth--; } } Region.setStartLoc(StartLoc); Region.setEndLoc(EndLoc); if (!isBranch) { MostRecentLocation = EndLoc; // If this region happens to span an entire expansion, we need to // make sure we don't overlap the parent region with it. if (StartLoc == getStartOfFileOrMacro(StartLoc) && EndLoc == getEndOfFileOrMacro(EndLoc)) MostRecentLocation = getIncludeOrExpansionLoc(EndLoc); } assert(SM.isWrittenInSameFile(Region.getBeginLoc(), EndLoc)); assert(SpellingRegion(SM, Region).isInSourceOrder()); SourceRegions.push_back(Region); } RegionStack.pop_back(); } } /// Return the currently active region. SourceMappingRegion &getRegion() { assert(!RegionStack.empty() && "statement has no region"); return RegionStack.back(); } /// Propagate counts through the children of \p S if \p VisitChildren is true. /// Otherwise, only emit a count for \p S itself. Counter propagateCounts(Counter TopCount, const Stmt *S, bool VisitChildren = true) { SourceLocation StartLoc = getStart(S); SourceLocation EndLoc = getEnd(S); size_t Index = pushRegion(TopCount, StartLoc, EndLoc); if (VisitChildren) Visit(S); Counter ExitCount = getRegion().getCounter(); popRegions(Index); // The statement may be spanned by an expansion. Make sure we handle a file // exit out of this expansion before moving to the next statement. if (SM.isBeforeInTranslationUnit(StartLoc, S->getBeginLoc())) MostRecentLocation = EndLoc; return ExitCount; } /// Determine whether the given condition can be constant folded. bool ConditionFoldsToBool(const Expr *Cond) { Expr::EvalResult Result; return (Cond->EvaluateAsInt(Result, CVM.getCodeGenModule().getContext())); } /// Create a Branch Region around an instrumentable condition for coverage /// and add it to the function's SourceRegions. A branch region tracks a /// "True" counter and a "False" counter for boolean expressions that /// result in the generation of a branch. void createBranchRegion(const Expr *C, Counter TrueCnt, Counter FalseCnt) { // Check for NULL conditions. if (!C) return; // Ensure we are an instrumentable condition (i.e. no "&&" or "||"). Push // region onto RegionStack but immediately pop it (which adds it to the // function's SourceRegions) because it doesn't apply to any other source // code other than the Condition. if (CodeGenFunction::isInstrumentedCondition(C)) { // If a condition can fold to true or false, the corresponding branch // will be removed. Create a region with both counters hard-coded to // zero. This allows us to visualize them in a special way. // Alternatively, we can prevent any optimization done via // constant-folding by ensuring that ConstantFoldsToSimpleInteger() in // CodeGenFunction.c always returns false, but that is very heavy-handed. if (ConditionFoldsToBool(C)) popRegions(pushRegion(Counter::getZero(), getStart(C), getEnd(C), Counter::getZero())); else // Otherwise, create a region with the True counter and False counter. popRegions(pushRegion(TrueCnt, getStart(C), getEnd(C), FalseCnt)); } } /// Create a Branch Region around a SwitchCase for code coverage /// and add it to the function's SourceRegions. void createSwitchCaseRegion(const SwitchCase *SC, Counter TrueCnt, Counter FalseCnt) { // Push region onto RegionStack but immediately pop it (which adds it to // the function's SourceRegions) because it doesn't apply to any other // source other than the SwitchCase. popRegions(pushRegion(TrueCnt, getStart(SC), SC->getColonLoc(), FalseCnt)); } /// Check whether a region with bounds \c StartLoc and \c EndLoc /// is already added to \c SourceRegions. bool isRegionAlreadyAdded(SourceLocation StartLoc, SourceLocation EndLoc, bool isBranch = false) { return llvm::any_of( llvm::reverse(SourceRegions), [&](const SourceMappingRegion &Region) { return Region.getBeginLoc() == StartLoc && Region.getEndLoc() == EndLoc && Region.isBranch() == isBranch; }); } /// Adjust the most recently visited location to \c EndLoc. /// /// This should be used after visiting any statements in non-source order. void adjustForOutOfOrderTraversal(SourceLocation EndLoc) { MostRecentLocation = EndLoc; // The code region for a whole macro is created in handleFileExit() when // it detects exiting of the virtual file of that macro. If we visited // statements in non-source order, we might already have such a region // added, for example, if a body of a loop is divided among multiple // macros. Avoid adding duplicate regions in such case. if (getRegion().hasEndLoc() && MostRecentLocation == getEndOfFileOrMacro(MostRecentLocation) && isRegionAlreadyAdded(getStartOfFileOrMacro(MostRecentLocation), MostRecentLocation, getRegion().isBranch())) MostRecentLocation = getIncludeOrExpansionLoc(MostRecentLocation); } /// Adjust regions and state when \c NewLoc exits a file. /// /// If moving from our most recently tracked location to \c NewLoc exits any /// files, this adjusts our current region stack and creates the file regions /// for the exited file. void handleFileExit(SourceLocation NewLoc) { if (NewLoc.isInvalid() || SM.isWrittenInSameFile(MostRecentLocation, NewLoc)) return; // If NewLoc is not in a file that contains MostRecentLocation, walk up to // find the common ancestor. SourceLocation LCA = NewLoc; FileID ParentFile = SM.getFileID(LCA); while (!isNestedIn(MostRecentLocation, ParentFile)) { LCA = getIncludeOrExpansionLoc(LCA); if (LCA.isInvalid() || SM.isWrittenInSameFile(LCA, MostRecentLocation)) { // Since there isn't a common ancestor, no file was exited. We just need // to adjust our location to the new file. MostRecentLocation = NewLoc; return; } ParentFile = SM.getFileID(LCA); } llvm::SmallSet StartLocs; std::optional ParentCounter; for (SourceMappingRegion &I : llvm::reverse(RegionStack)) { if (!I.hasStartLoc()) continue; SourceLocation Loc = I.getBeginLoc(); if (!isNestedIn(Loc, ParentFile)) { ParentCounter = I.getCounter(); break; } while (!SM.isInFileID(Loc, ParentFile)) { // The most nested region for each start location is the one with the // correct count. We avoid creating redundant regions by stopping once // we've seen this region. if (StartLocs.insert(Loc).second) { if (I.isBranch()) SourceRegions.emplace_back(I.getCounter(), I.getFalseCounter(), Loc, getEndOfFileOrMacro(Loc), I.isBranch()); else SourceRegions.emplace_back(I.getCounter(), Loc, getEndOfFileOrMacro(Loc)); } Loc = getIncludeOrExpansionLoc(Loc); } I.setStartLoc(getPreciseTokenLocEnd(Loc)); } if (ParentCounter) { // If the file is contained completely by another region and doesn't // immediately start its own region, the whole file gets a region // corresponding to the parent. SourceLocation Loc = MostRecentLocation; while (isNestedIn(Loc, ParentFile)) { SourceLocation FileStart = getStartOfFileOrMacro(Loc); if (StartLocs.insert(FileStart).second) { SourceRegions.emplace_back(*ParentCounter, FileStart, getEndOfFileOrMacro(Loc)); assert(SpellingRegion(SM, SourceRegions.back()).isInSourceOrder()); } Loc = getIncludeOrExpansionLoc(Loc); } } MostRecentLocation = NewLoc; } /// Ensure that \c S is included in the current region. void extendRegion(const Stmt *S) { SourceMappingRegion &Region = getRegion(); SourceLocation StartLoc = getStart(S); handleFileExit(StartLoc); if (!Region.hasStartLoc()) Region.setStartLoc(StartLoc); } /// Mark \c S as a terminator, starting a zero region. void terminateRegion(const Stmt *S) { extendRegion(S); SourceMappingRegion &Region = getRegion(); SourceLocation EndLoc = getEnd(S); if (!Region.hasEndLoc()) Region.setEndLoc(EndLoc); pushRegion(Counter::getZero()); HasTerminateStmt = true; } /// Find a valid gap range between \p AfterLoc and \p BeforeLoc. std::optional findGapAreaBetween(SourceLocation AfterLoc, SourceLocation BeforeLoc) { // If AfterLoc is in function-like macro, use the right parenthesis // location. if (AfterLoc.isMacroID()) { FileID FID = SM.getFileID(AfterLoc); const SrcMgr::ExpansionInfo *EI = &SM.getSLocEntry(FID).getExpansion(); if (EI->isFunctionMacroExpansion()) AfterLoc = EI->getExpansionLocEnd(); } size_t StartDepth = locationDepth(AfterLoc); size_t EndDepth = locationDepth(BeforeLoc); while (!SM.isWrittenInSameFile(AfterLoc, BeforeLoc)) { bool UnnestStart = StartDepth >= EndDepth; bool UnnestEnd = EndDepth >= StartDepth; if (UnnestEnd) { assert(SM.isWrittenInSameFile(getStartOfFileOrMacro(BeforeLoc), BeforeLoc)); BeforeLoc = getIncludeOrExpansionLoc(BeforeLoc); assert(BeforeLoc.isValid()); EndDepth--; } if (UnnestStart) { assert(SM.isWrittenInSameFile(AfterLoc, getEndOfFileOrMacro(AfterLoc))); AfterLoc = getIncludeOrExpansionLoc(AfterLoc); assert(AfterLoc.isValid()); AfterLoc = getPreciseTokenLocEnd(AfterLoc); assert(AfterLoc.isValid()); StartDepth--; } } AfterLoc = getPreciseTokenLocEnd(AfterLoc); // If the start and end locations of the gap are both within the same macro // file, the range may not be in source order. if (AfterLoc.isMacroID() || BeforeLoc.isMacroID()) return std::nullopt; if (!SM.isWrittenInSameFile(AfterLoc, BeforeLoc) || !SpellingRegion(SM, AfterLoc, BeforeLoc).isInSourceOrder()) return std::nullopt; return {{AfterLoc, BeforeLoc}}; } /// Emit a gap region between \p StartLoc and \p EndLoc with the given count. void fillGapAreaWithCount(SourceLocation StartLoc, SourceLocation EndLoc, Counter Count) { if (StartLoc == EndLoc) return; assert(SpellingRegion(SM, StartLoc, EndLoc).isInSourceOrder()); handleFileExit(StartLoc); size_t Index = pushRegion(Count, StartLoc, EndLoc); getRegion().setGap(true); handleFileExit(EndLoc); popRegions(Index); } /// Keep counts of breaks and continues inside loops. struct BreakContinue { Counter BreakCount; Counter ContinueCount; }; SmallVector BreakContinueStack; CounterCoverageMappingBuilder( CoverageMappingModuleGen &CVM, llvm::DenseMap &CounterMap, SourceManager &SM, const LangOptions &LangOpts) : CoverageMappingBuilder(CVM, SM, LangOpts), CounterMap(CounterMap) {} /// Write the mapping data to the output stream void write(llvm::raw_ostream &OS) { llvm::SmallVector VirtualFileMapping; gatherFileIDs(VirtualFileMapping); SourceRegionFilter Filter = emitExpansionRegions(); emitSourceRegions(Filter); gatherSkippedRegions(); if (MappingRegions.empty()) return; CoverageMappingWriter Writer(VirtualFileMapping, Builder.getExpressions(), MappingRegions); Writer.write(OS); } void VisitStmt(const Stmt *S) { if (S->getBeginLoc().isValid()) extendRegion(S); const Stmt *LastStmt = nullptr; bool SaveTerminateStmt = HasTerminateStmt; HasTerminateStmt = false; GapRegionCounter = Counter::getZero(); for (const Stmt *Child : S->children()) if (Child) { // If last statement contains terminate statements, add a gap area // between the two statements. Skipping attributed statements, because // they don't have valid start location. if (LastStmt && HasTerminateStmt && !isa(Child)) { auto Gap = findGapAreaBetween(getEnd(LastStmt), getStart(Child)); if (Gap) fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), GapRegionCounter); SaveTerminateStmt = true; HasTerminateStmt = false; } this->Visit(Child); LastStmt = Child; } if (SaveTerminateStmt) HasTerminateStmt = true; handleFileExit(getEnd(S)); } void VisitDecl(const Decl *D) { Stmt *Body = D->getBody(); // Do not propagate region counts into system headers unless collecting // coverage from system headers is explicitly enabled. if (!SystemHeadersCoverage && Body && SM.isInSystemHeader(SM.getSpellingLoc(getStart(Body)))) return; // Do not visit the artificial children nodes of defaulted methods. The // lexer may not be able to report back precise token end locations for // these children nodes (llvm.org/PR39822), and moreover users will not be // able to see coverage for them. Counter BodyCounter = getRegionCounter(Body); bool Defaulted = false; if (auto *Method = dyn_cast(D)) Defaulted = Method->isDefaulted(); if (auto *Ctor = dyn_cast(D)) { for (auto *Initializer : Ctor->inits()) { if (Initializer->isWritten()) { auto *Init = Initializer->getInit(); if (getStart(Init).isValid() && getEnd(Init).isValid()) propagateCounts(BodyCounter, Init); } } } propagateCounts(BodyCounter, Body, /*VisitChildren=*/!Defaulted); assert(RegionStack.empty() && "Regions entered but never exited"); } void VisitReturnStmt(const ReturnStmt *S) { extendRegion(S); if (S->getRetValue()) Visit(S->getRetValue()); terminateRegion(S); } void VisitCoroutineBodyStmt(const CoroutineBodyStmt *S) { extendRegion(S); Visit(S->getBody()); } void VisitCoreturnStmt(const CoreturnStmt *S) { extendRegion(S); if (S->getOperand()) Visit(S->getOperand()); terminateRegion(S); } void VisitCXXThrowExpr(const CXXThrowExpr *E) { extendRegion(E); if (E->getSubExpr()) Visit(E->getSubExpr()); terminateRegion(E); } void VisitGotoStmt(const GotoStmt *S) { terminateRegion(S); } void VisitLabelStmt(const LabelStmt *S) { Counter LabelCount = getRegionCounter(S); SourceLocation Start = getStart(S); // We can't extendRegion here or we risk overlapping with our new region. handleFileExit(Start); pushRegion(LabelCount, Start); Visit(S->getSubStmt()); } void VisitBreakStmt(const BreakStmt *S) { assert(!BreakContinueStack.empty() && "break not in a loop or switch!"); BreakContinueStack.back().BreakCount = addCounters( BreakContinueStack.back().BreakCount, getRegion().getCounter()); // FIXME: a break in a switch should terminate regions for all preceding // case statements, not just the most recent one. terminateRegion(S); } void VisitContinueStmt(const ContinueStmt *S) { assert(!BreakContinueStack.empty() && "continue stmt not in a loop!"); BreakContinueStack.back().ContinueCount = addCounters( BreakContinueStack.back().ContinueCount, getRegion().getCounter()); terminateRegion(S); } void VisitCallExpr(const CallExpr *E) { VisitStmt(E); // Terminate the region when we hit a noreturn function. // (This is helpful dealing with switch statements.) QualType CalleeType = E->getCallee()->getType(); if (getFunctionExtInfo(*CalleeType).getNoReturn()) terminateRegion(E); } void VisitWhileStmt(const WhileStmt *S) { extendRegion(S); Counter ParentCount = getRegion().getCounter(); Counter BodyCount = getRegionCounter(S); // Handle the body first so that we can get the backedge count. BreakContinueStack.push_back(BreakContinue()); extendRegion(S->getBody()); Counter BackedgeCount = propagateCounts(BodyCount, S->getBody()); BreakContinue BC = BreakContinueStack.pop_back_val(); bool BodyHasTerminateStmt = HasTerminateStmt; HasTerminateStmt = false; // Go back to handle the condition. Counter CondCount = addCounters(ParentCount, BackedgeCount, BC.ContinueCount); propagateCounts(CondCount, S->getCond()); adjustForOutOfOrderTraversal(getEnd(S)); // The body count applies to the area immediately after the increment. auto Gap = findGapAreaBetween(S->getRParenLoc(), getStart(S->getBody())); if (Gap) fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), BodyCount); Counter OutCount = addCounters(BC.BreakCount, subtractCounters(CondCount, BodyCount)); if (OutCount != ParentCount) { pushRegion(OutCount); GapRegionCounter = OutCount; if (BodyHasTerminateStmt) HasTerminateStmt = true; } // Create Branch Region around condition. createBranchRegion(S->getCond(), BodyCount, subtractCounters(CondCount, BodyCount)); } void VisitDoStmt(const DoStmt *S) { extendRegion(S); Counter ParentCount = getRegion().getCounter(); Counter BodyCount = getRegionCounter(S); BreakContinueStack.push_back(BreakContinue()); extendRegion(S->getBody()); Counter BackedgeCount = propagateCounts(addCounters(ParentCount, BodyCount), S->getBody()); BreakContinue BC = BreakContinueStack.pop_back_val(); bool BodyHasTerminateStmt = HasTerminateStmt; HasTerminateStmt = false; Counter CondCount = addCounters(BackedgeCount, BC.ContinueCount); propagateCounts(CondCount, S->getCond()); Counter OutCount = addCounters(BC.BreakCount, subtractCounters(CondCount, BodyCount)); if (OutCount != ParentCount) { pushRegion(OutCount); GapRegionCounter = OutCount; } // Create Branch Region around condition. createBranchRegion(S->getCond(), BodyCount, subtractCounters(CondCount, BodyCount)); if (BodyHasTerminateStmt) HasTerminateStmt = true; } void VisitForStmt(const ForStmt *S) { extendRegion(S); if (S->getInit()) Visit(S->getInit()); Counter ParentCount = getRegion().getCounter(); Counter BodyCount = getRegionCounter(S); // The loop increment may contain a break or continue. if (S->getInc()) BreakContinueStack.emplace_back(); // Handle the body first so that we can get the backedge count. BreakContinueStack.emplace_back(); extendRegion(S->getBody()); Counter BackedgeCount = propagateCounts(BodyCount, S->getBody()); BreakContinue BodyBC = BreakContinueStack.pop_back_val(); bool BodyHasTerminateStmt = HasTerminateStmt; HasTerminateStmt = false; // The increment is essentially part of the body but it needs to include // the count for all the continue statements. BreakContinue IncrementBC; if (const Stmt *Inc = S->getInc()) { propagateCounts(addCounters(BackedgeCount, BodyBC.ContinueCount), Inc); IncrementBC = BreakContinueStack.pop_back_val(); } // Go back to handle the condition. Counter CondCount = addCounters( addCounters(ParentCount, BackedgeCount, BodyBC.ContinueCount), IncrementBC.ContinueCount); if (const Expr *Cond = S->getCond()) { propagateCounts(CondCount, Cond); adjustForOutOfOrderTraversal(getEnd(S)); } // The body count applies to the area immediately after the increment. auto Gap = findGapAreaBetween(S->getRParenLoc(), getStart(S->getBody())); if (Gap) fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), BodyCount); Counter OutCount = addCounters(BodyBC.BreakCount, IncrementBC.BreakCount, subtractCounters(CondCount, BodyCount)); if (OutCount != ParentCount) { pushRegion(OutCount); GapRegionCounter = OutCount; if (BodyHasTerminateStmt) HasTerminateStmt = true; } // Create Branch Region around condition. createBranchRegion(S->getCond(), BodyCount, subtractCounters(CondCount, BodyCount)); } void VisitCXXForRangeStmt(const CXXForRangeStmt *S) { extendRegion(S); if (S->getInit()) Visit(S->getInit()); Visit(S->getLoopVarStmt()); Visit(S->getRangeStmt()); Counter ParentCount = getRegion().getCounter(); Counter BodyCount = getRegionCounter(S); BreakContinueStack.push_back(BreakContinue()); extendRegion(S->getBody()); Counter BackedgeCount = propagateCounts(BodyCount, S->getBody()); BreakContinue BC = BreakContinueStack.pop_back_val(); bool BodyHasTerminateStmt = HasTerminateStmt; HasTerminateStmt = false; // The body count applies to the area immediately after the range. auto Gap = findGapAreaBetween(S->getRParenLoc(), getStart(S->getBody())); if (Gap) fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), BodyCount); Counter LoopCount = addCounters(ParentCount, BackedgeCount, BC.ContinueCount); Counter OutCount = addCounters(BC.BreakCount, subtractCounters(LoopCount, BodyCount)); if (OutCount != ParentCount) { pushRegion(OutCount); GapRegionCounter = OutCount; if (BodyHasTerminateStmt) HasTerminateStmt = true; } // Create Branch Region around condition. createBranchRegion(S->getCond(), BodyCount, subtractCounters(LoopCount, BodyCount)); } void VisitObjCForCollectionStmt(const ObjCForCollectionStmt *S) { extendRegion(S); Visit(S->getElement()); Counter ParentCount = getRegion().getCounter(); Counter BodyCount = getRegionCounter(S); BreakContinueStack.push_back(BreakContinue()); extendRegion(S->getBody()); Counter BackedgeCount = propagateCounts(BodyCount, S->getBody()); BreakContinue BC = BreakContinueStack.pop_back_val(); // The body count applies to the area immediately after the collection. auto Gap = findGapAreaBetween(S->getRParenLoc(), getStart(S->getBody())); if (Gap) fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), BodyCount); Counter LoopCount = addCounters(ParentCount, BackedgeCount, BC.ContinueCount); Counter OutCount = addCounters(BC.BreakCount, subtractCounters(LoopCount, BodyCount)); if (OutCount != ParentCount) { pushRegion(OutCount); GapRegionCounter = OutCount; } } void VisitSwitchStmt(const SwitchStmt *S) { extendRegion(S); if (S->getInit()) Visit(S->getInit()); Visit(S->getCond()); BreakContinueStack.push_back(BreakContinue()); const Stmt *Body = S->getBody(); extendRegion(Body); if (const auto *CS = dyn_cast(Body)) { if (!CS->body_empty()) { // Make a region for the body of the switch. If the body starts with // a case, that case will reuse this region; otherwise, this covers // the unreachable code at the beginning of the switch body. size_t Index = pushRegion(Counter::getZero(), getStart(CS)); getRegion().setGap(true); Visit(Body); // Set the end for the body of the switch, if it isn't already set. for (size_t i = RegionStack.size(); i != Index; --i) { if (!RegionStack[i - 1].hasEndLoc()) RegionStack[i - 1].setEndLoc(getEnd(CS->body_back())); } popRegions(Index); } } else propagateCounts(Counter::getZero(), Body); BreakContinue BC = BreakContinueStack.pop_back_val(); if (!BreakContinueStack.empty()) BreakContinueStack.back().ContinueCount = addCounters( BreakContinueStack.back().ContinueCount, BC.ContinueCount); Counter ParentCount = getRegion().getCounter(); Counter ExitCount = getRegionCounter(S); SourceLocation ExitLoc = getEnd(S); pushRegion(ExitCount); GapRegionCounter = ExitCount; // Ensure that handleFileExit recognizes when the end location is located // in a different file. MostRecentLocation = getStart(S); handleFileExit(ExitLoc); // Create a Branch Region around each Case. Subtract the case's // counter from the Parent counter to track the "False" branch count. Counter CaseCountSum; bool HasDefaultCase = false; const SwitchCase *Case = S->getSwitchCaseList(); for (; Case; Case = Case->getNextSwitchCase()) { HasDefaultCase = HasDefaultCase || isa(Case); CaseCountSum = addCounters(CaseCountSum, getRegionCounter(Case), /*Simplify=*/false); createSwitchCaseRegion( Case, getRegionCounter(Case), subtractCounters(ParentCount, getRegionCounter(Case))); } // Simplify is skipped while building the counters above: it can get really // slow on top of switches with thousands of cases. Instead, trigger // simplification by adding zero to the last counter. CaseCountSum = addCounters(CaseCountSum, Counter::getZero()); // If no explicit default case exists, create a branch region to represent // the hidden branch, which will be added later by the CodeGen. This region // will be associated with the switch statement's condition. if (!HasDefaultCase) { Counter DefaultTrue = subtractCounters(ParentCount, CaseCountSum); Counter DefaultFalse = subtractCounters(ParentCount, DefaultTrue); createBranchRegion(S->getCond(), DefaultTrue, DefaultFalse); } } void VisitSwitchCase(const SwitchCase *S) { extendRegion(S); SourceMappingRegion &Parent = getRegion(); Counter Count = addCounters(Parent.getCounter(), getRegionCounter(S)); // Reuse the existing region if it starts at our label. This is typical of // the first case in a switch. if (Parent.hasStartLoc() && Parent.getBeginLoc() == getStart(S)) Parent.setCounter(Count); else pushRegion(Count, getStart(S)); GapRegionCounter = Count; if (const auto *CS = dyn_cast(S)) { Visit(CS->getLHS()); if (const Expr *RHS = CS->getRHS()) Visit(RHS); } Visit(S->getSubStmt()); } void VisitIfStmt(const IfStmt *S) { extendRegion(S); if (S->getInit()) Visit(S->getInit()); // Extend into the condition before we propagate through it below - this is // needed to handle macros that generate the "if" but not the condition. if (!S->isConsteval()) extendRegion(S->getCond()); Counter ParentCount = getRegion().getCounter(); Counter ThenCount = getRegionCounter(S); if (!S->isConsteval()) { // Emitting a counter for the condition makes it easier to interpret the // counter for the body when looking at the coverage. propagateCounts(ParentCount, S->getCond()); // The 'then' count applies to the area immediately after the condition. std::optional Gap = findGapAreaBetween(S->getRParenLoc(), getStart(S->getThen())); if (Gap) fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), ThenCount); } extendRegion(S->getThen()); Counter OutCount = propagateCounts(ThenCount, S->getThen()); Counter ElseCount = subtractCounters(ParentCount, ThenCount); if (const Stmt *Else = S->getElse()) { bool ThenHasTerminateStmt = HasTerminateStmt; HasTerminateStmt = false; // The 'else' count applies to the area immediately after the 'then'. std::optional Gap = findGapAreaBetween(getEnd(S->getThen()), getStart(Else)); if (Gap) fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), ElseCount); extendRegion(Else); OutCount = addCounters(OutCount, propagateCounts(ElseCount, Else)); if (ThenHasTerminateStmt) HasTerminateStmt = true; } else OutCount = addCounters(OutCount, ElseCount); if (OutCount != ParentCount) { pushRegion(OutCount); GapRegionCounter = OutCount; } if (!S->isConsteval()) { // Create Branch Region around condition. createBranchRegion(S->getCond(), ThenCount, subtractCounters(ParentCount, ThenCount)); } } void VisitCXXTryStmt(const CXXTryStmt *S) { extendRegion(S); // Handle macros that generate the "try" but not the rest. extendRegion(S->getTryBlock()); Counter ParentCount = getRegion().getCounter(); propagateCounts(ParentCount, S->getTryBlock()); for (unsigned I = 0, E = S->getNumHandlers(); I < E; ++I) Visit(S->getHandler(I)); Counter ExitCount = getRegionCounter(S); pushRegion(ExitCount); } void VisitCXXCatchStmt(const CXXCatchStmt *S) { propagateCounts(getRegionCounter(S), S->getHandlerBlock()); } void VisitAbstractConditionalOperator(const AbstractConditionalOperator *E) { extendRegion(E); Counter ParentCount = getRegion().getCounter(); Counter TrueCount = getRegionCounter(E); propagateCounts(ParentCount, E->getCond()); Counter OutCount; if (!isa(E)) { // The 'then' count applies to the area immediately after the condition. auto Gap = findGapAreaBetween(E->getQuestionLoc(), getStart(E->getTrueExpr())); if (Gap) fillGapAreaWithCount(Gap->getBegin(), Gap->getEnd(), TrueCount); extendRegion(E->getTrueExpr()); OutCount = propagateCounts(TrueCount, E->getTrueExpr()); } extendRegion(E->getFalseExpr()); OutCount = addCounters( OutCount, propagateCounts(subtractCounters(ParentCount, TrueCount), E->getFalseExpr())); if (OutCount != ParentCount) { pushRegion(OutCount); GapRegionCounter = OutCount; } // Create Branch Region around condition. createBranchRegion(E->getCond(), TrueCount, subtractCounters(ParentCount, TrueCount)); } void VisitBinLAnd(const BinaryOperator *E) { extendRegion(E->getLHS()); propagateCounts(getRegion().getCounter(), E->getLHS()); handleFileExit(getEnd(E->getLHS())); // Counter tracks the right hand side of a logical and operator. extendRegion(E->getRHS()); propagateCounts(getRegionCounter(E), E->getRHS()); // Extract the RHS's Execution Counter. Counter RHSExecCnt = getRegionCounter(E); // Extract the RHS's "True" Instance Counter. Counter RHSTrueCnt = getRegionCounter(E->getRHS()); // Extract the Parent Region Counter. Counter ParentCnt = getRegion().getCounter(); // Create Branch Region around LHS condition. createBranchRegion(E->getLHS(), RHSExecCnt, subtractCounters(ParentCnt, RHSExecCnt)); // Create Branch Region around RHS condition. createBranchRegion(E->getRHS(), RHSTrueCnt, subtractCounters(RHSExecCnt, RHSTrueCnt)); } // Determine whether the right side of OR operation need to be visited. bool shouldVisitRHS(const Expr *LHS) { bool LHSIsTrue = false; bool LHSIsConst = false; if (!LHS->isValueDependent()) LHSIsConst = LHS->EvaluateAsBooleanCondition( LHSIsTrue, CVM.getCodeGenModule().getContext()); return !LHSIsConst || (LHSIsConst && !LHSIsTrue); } void VisitBinLOr(const BinaryOperator *E) { extendRegion(E->getLHS()); Counter OutCount = propagateCounts(getRegion().getCounter(), E->getLHS()); handleFileExit(getEnd(E->getLHS())); // Counter tracks the right hand side of a logical or operator. extendRegion(E->getRHS()); propagateCounts(getRegionCounter(E), E->getRHS()); // Extract the RHS's Execution Counter. Counter RHSExecCnt = getRegionCounter(E); // Extract the RHS's "False" Instance Counter. Counter RHSFalseCnt = getRegionCounter(E->getRHS()); if (!shouldVisitRHS(E->getLHS())) { GapRegionCounter = OutCount; } // Extract the Parent Region Counter. Counter ParentCnt = getRegion().getCounter(); // Create Branch Region around LHS condition. createBranchRegion(E->getLHS(), subtractCounters(ParentCnt, RHSExecCnt), RHSExecCnt); // Create Branch Region around RHS condition. createBranchRegion(E->getRHS(), subtractCounters(RHSExecCnt, RHSFalseCnt), RHSFalseCnt); } void VisitLambdaExpr(const LambdaExpr *LE) { // Lambdas are treated as their own functions for now, so we shouldn't // propagate counts into them. } void VisitPseudoObjectExpr(const PseudoObjectExpr *POE) { // Just visit syntatic expression as this is what users actually write. VisitStmt(POE->getSyntacticForm()); } void VisitOpaqueValueExpr(const OpaqueValueExpr* OVE) { Visit(OVE->getSourceExpr()); } }; } // end anonymous namespace static void dump(llvm::raw_ostream &OS, StringRef FunctionName, ArrayRef Expressions, ArrayRef Regions) { OS << FunctionName << ":\n"; CounterMappingContext Ctx(Expressions); for (const auto &R : Regions) { OS.indent(2); switch (R.Kind) { case CounterMappingRegion::CodeRegion: break; case CounterMappingRegion::ExpansionRegion: OS << "Expansion,"; break; case CounterMappingRegion::SkippedRegion: OS << "Skipped,"; break; case CounterMappingRegion::GapRegion: OS << "Gap,"; break; case CounterMappingRegion::BranchRegion: case CounterMappingRegion::MCDCBranchRegion: OS << "Branch,"; break; case CounterMappingRegion::MCDCDecisionRegion: OS << "Decision,"; break; } OS << "File " << R.FileID << ", " << R.LineStart << ":" << R.ColumnStart << " -> " << R.LineEnd << ":" << R.ColumnEnd << " = "; Ctx.dump(R.Count, OS); if (R.Kind == CounterMappingRegion::BranchRegion) { OS << ", "; Ctx.dump(R.FalseCount, OS); } if (R.Kind == CounterMappingRegion::ExpansionRegion) OS << " (Expanded file = " << R.ExpandedFileID << ")"; OS << "\n"; } } CoverageMappingModuleGen::CoverageMappingModuleGen( CodeGenModule &CGM, CoverageSourceInfo &SourceInfo) : CGM(CGM), SourceInfo(SourceInfo) {} std::string CoverageMappingModuleGen::getCurrentDirname() { if (!CGM.getCodeGenOpts().CoverageCompilationDir.empty()) return CGM.getCodeGenOpts().CoverageCompilationDir; SmallString<256> CWD; llvm::sys::fs::current_path(CWD); return CWD.str().str(); } std::string CoverageMappingModuleGen::normalizeFilename(StringRef Filename) { llvm::SmallString<256> Path(Filename); llvm::sys::path::remove_dots(Path, /*remove_dot_dot=*/true); /// Traverse coverage prefix map in reverse order because prefix replacements /// are applied in reverse order starting from the last one when multiple /// prefix replacement options are provided. for (const auto &[From, To] : llvm::reverse(CGM.getCodeGenOpts().CoveragePrefixMap)) { if (llvm::sys::path::replace_path_prefix(Path, From, To)) break; } return Path.str().str(); } static std::string getInstrProfSection(const CodeGenModule &CGM, llvm::InstrProfSectKind SK) { return llvm::getInstrProfSectionName( SK, CGM.getContext().getTargetInfo().getTriple().getObjectFormat()); } void CoverageMappingModuleGen::emitFunctionMappingRecord( const FunctionInfo &Info, uint64_t FilenamesRef) { llvm::LLVMContext &Ctx = CGM.getLLVMContext(); // Assign a name to the function record. This is used to merge duplicates. std::string FuncRecordName = "__covrec_" + llvm::utohexstr(Info.NameHash); // A dummy description for a function included-but-not-used in a TU can be // replaced by full description provided by a different TU. The two kinds of // descriptions play distinct roles: therefore, assign them different names // to prevent `linkonce_odr` merging. if (Info.IsUsed) FuncRecordName += "u"; // Create the function record type. const uint64_t NameHash = Info.NameHash; const uint64_t FuncHash = Info.FuncHash; const std::string &CoverageMapping = Info.CoverageMapping; #define COVMAP_FUNC_RECORD(Type, LLVMType, Name, Init) LLVMType, llvm::Type *FunctionRecordTypes[] = { #include "llvm/ProfileData/InstrProfData.inc" }; auto *FunctionRecordTy = llvm::StructType::get(Ctx, ArrayRef(FunctionRecordTypes), /*isPacked=*/true); // Create the function record constant. #define COVMAP_FUNC_RECORD(Type, LLVMType, Name, Init) Init, llvm::Constant *FunctionRecordVals[] = { #include "llvm/ProfileData/InstrProfData.inc" }; auto *FuncRecordConstant = llvm::ConstantStruct::get(FunctionRecordTy, ArrayRef(FunctionRecordVals)); // Create the function record global. auto *FuncRecord = new llvm::GlobalVariable( CGM.getModule(), FunctionRecordTy, /*isConstant=*/true, llvm::GlobalValue::LinkOnceODRLinkage, FuncRecordConstant, FuncRecordName); FuncRecord->setVisibility(llvm::GlobalValue::HiddenVisibility); FuncRecord->setSection(getInstrProfSection(CGM, llvm::IPSK_covfun)); FuncRecord->setAlignment(llvm::Align(8)); if (CGM.supportsCOMDAT()) FuncRecord->setComdat(CGM.getModule().getOrInsertComdat(FuncRecordName)); // Make sure the data doesn't get deleted. CGM.addUsedGlobal(FuncRecord); } void CoverageMappingModuleGen::addFunctionMappingRecord( llvm::GlobalVariable *NamePtr, StringRef NameValue, uint64_t FuncHash, const std::string &CoverageMapping, bool IsUsed) { const uint64_t NameHash = llvm::IndexedInstrProf::ComputeHash(NameValue); FunctionRecords.push_back({NameHash, FuncHash, CoverageMapping, IsUsed}); if (!IsUsed) FunctionNames.push_back(NamePtr); if (CGM.getCodeGenOpts().DumpCoverageMapping) { // Dump the coverage mapping data for this function by decoding the // encoded data. This allows us to dump the mapping regions which were // also processed by the CoverageMappingWriter which performs // additional minimization operations such as reducing the number of // expressions. llvm::SmallVector FilenameStrs; std::vector Filenames; std::vector Expressions; std::vector Regions; FilenameStrs.resize(FileEntries.size() + 1); FilenameStrs[0] = normalizeFilename(getCurrentDirname()); for (const auto &Entry : FileEntries) { auto I = Entry.second; FilenameStrs[I] = normalizeFilename(Entry.first.getName()); } ArrayRef FilenameRefs = llvm::ArrayRef(FilenameStrs); RawCoverageMappingReader Reader(CoverageMapping, FilenameRefs, Filenames, Expressions, Regions); if (Reader.read()) return; dump(llvm::outs(), NameValue, Expressions, Regions); } } void CoverageMappingModuleGen::emit() { if (FunctionRecords.empty()) return; llvm::LLVMContext &Ctx = CGM.getLLVMContext(); auto *Int32Ty = llvm::Type::getInt32Ty(Ctx); // Create the filenames and merge them with coverage mappings llvm::SmallVector FilenameStrs; FilenameStrs.resize(FileEntries.size() + 1); // The first filename is the current working directory. FilenameStrs[0] = normalizeFilename(getCurrentDirname()); for (const auto &Entry : FileEntries) { auto I = Entry.second; FilenameStrs[I] = normalizeFilename(Entry.first.getName()); } std::string Filenames; { llvm::raw_string_ostream OS(Filenames); CoverageFilenamesSectionWriter(FilenameStrs).write(OS); } auto *FilenamesVal = llvm::ConstantDataArray::getString(Ctx, Filenames, false); const int64_t FilenamesRef = llvm::IndexedInstrProf::ComputeHash(Filenames); // Emit the function records. for (const FunctionInfo &Info : FunctionRecords) emitFunctionMappingRecord(Info, FilenamesRef); const unsigned NRecords = 0; const size_t FilenamesSize = Filenames.size(); const unsigned CoverageMappingSize = 0; llvm::Type *CovDataHeaderTypes[] = { #define COVMAP_HEADER(Type, LLVMType, Name, Init) LLVMType, #include "llvm/ProfileData/InstrProfData.inc" }; auto CovDataHeaderTy = llvm::StructType::get(Ctx, ArrayRef(CovDataHeaderTypes)); llvm::Constant *CovDataHeaderVals[] = { #define COVMAP_HEADER(Type, LLVMType, Name, Init) Init, #include "llvm/ProfileData/InstrProfData.inc" }; auto CovDataHeaderVal = llvm::ConstantStruct::get(CovDataHeaderTy, ArrayRef(CovDataHeaderVals)); // Create the coverage data record llvm::Type *CovDataTypes[] = {CovDataHeaderTy, FilenamesVal->getType()}; auto CovDataTy = llvm::StructType::get(Ctx, ArrayRef(CovDataTypes)); llvm::Constant *TUDataVals[] = {CovDataHeaderVal, FilenamesVal}; auto CovDataVal = llvm::ConstantStruct::get(CovDataTy, ArrayRef(TUDataVals)); auto CovData = new llvm::GlobalVariable( CGM.getModule(), CovDataTy, true, llvm::GlobalValue::PrivateLinkage, CovDataVal, llvm::getCoverageMappingVarName()); CovData->setSection(getInstrProfSection(CGM, llvm::IPSK_covmap)); CovData->setAlignment(llvm::Align(8)); // Make sure the data doesn't get deleted. CGM.addUsedGlobal(CovData); // Create the deferred function records array if (!FunctionNames.empty()) { auto NamesArrTy = llvm::ArrayType::get(llvm::PointerType::getUnqual(Ctx), FunctionNames.size()); auto NamesArrVal = llvm::ConstantArray::get(NamesArrTy, FunctionNames); // This variable will *NOT* be emitted to the object file. It is used // to pass the list of names referenced to codegen. new llvm::GlobalVariable(CGM.getModule(), NamesArrTy, true, llvm::GlobalValue::InternalLinkage, NamesArrVal, llvm::getCoverageUnusedNamesVarName()); } } unsigned CoverageMappingModuleGen::getFileID(FileEntryRef File) { auto It = FileEntries.find(File); if (It != FileEntries.end()) return It->second; unsigned FileID = FileEntries.size() + 1; FileEntries.insert(std::make_pair(File, FileID)); return FileID; } void CoverageMappingGen::emitCounterMapping(const Decl *D, llvm::raw_ostream &OS) { assert(CounterMap); CounterCoverageMappingBuilder Walker(CVM, *CounterMap, SM, LangOpts); Walker.VisitDecl(D); Walker.write(OS); } void CoverageMappingGen::emitEmptyMapping(const Decl *D, llvm::raw_ostream &OS) { EmptyCoverageMappingBuilder Walker(CVM, SM, LangOpts); Walker.VisitDecl(D); Walker.write(OS); }