clang/lib/CodeGen/CoverageMappingGen.h

   1 //===---- CoverageMappingGen.h - Coverage mapping generation ----*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // Instrumentation-based code coverage mapping generator
  10 //
  11 //===----------------------------------------------------------------------===//
  12
  13 #ifndef LLVM_CLANG_LIB_CODEGEN_COVERAGEMAPPINGGEN_H
  14 #define LLVM_CLANG_LIB_CODEGEN_COVERAGEMAPPINGGEN_H
  15
  16 #include "clang/Basic/LLVM.h"
  17 #include "clang/Basic/SourceLocation.h"
  18 #include "clang/Lex/PPCallbacks.h"
  19 #include "clang/Lex/Preprocessor.h"
  20 #include "llvm/ADT/DenseMap.h"
  21 #include "llvm/IR/GlobalValue.h"
  22 #include "llvm/Support/raw_ostream.h"
  23
  24 namespace clang {
  25
  26 class LangOptions;
  27 class SourceManager;
  28 class FileEntry;
  29 class Preprocessor;
  30 class Decl;
  31 class Stmt;
  32
  33 struct SkippedRange {
  34   enum Kind {
  35     PPIfElse, // Preprocessor #if/#else ...
  36     EmptyLine,
  37     Comment,
  38   };
  39
  40   SourceRange Range;
  41   // The location of token before the skipped source range.
  42   SourceLocation PrevTokLoc;
  43   // The location of token after the skipped source range.
  44   SourceLocation NextTokLoc;
  45   // The nature of this skipped range
  46   Kind RangeKind;
  47
  48   bool isComment() { return RangeKind == Comment; }
  49   bool isEmptyLine() { return RangeKind == EmptyLine; }
  50   bool isPPIfElse() { return RangeKind == PPIfElse; }
  51
  52   SkippedRange(SourceRange Range, Kind K,
  53                SourceLocation PrevTokLoc = SourceLocation(),
  54                SourceLocation NextTokLoc = SourceLocation())
  55       : Range(Range), PrevTokLoc(PrevTokLoc), NextTokLoc(NextTokLoc),
  56         RangeKind(K) {}
  57 };
  58
  59 /// Stores additional source code information like skipped ranges which
  60 /// is required by the coverage mapping generator and is obtained from
  61 /// the preprocessor.
  62 class CoverageSourceInfo : public PPCallbacks,
  63                            public CommentHandler,
  64                            public EmptylineHandler {
  65   // A vector of skipped source ranges and PrevTokLoc with NextTokLoc.
  66   std::vector<SkippedRange> SkippedRanges;
  67
  68   SourceManager &SourceMgr;
  69
  70 public:
  71   // Location of the token parsed before HandleComment is called. This is
  72   // updated every time Preprocessor::Lex lexes a new token.
  73   SourceLocation PrevTokLoc;
  74
  75   CoverageSourceInfo(SourceManager &SourceMgr) : SourceMgr(SourceMgr) {}
  76
  77   std::vector<SkippedRange> &getSkippedRanges() { return SkippedRanges; }
  78
  79   void AddSkippedRange(SourceRange Range, SkippedRange::Kind RangeKind);
  80
  81   void SourceRangeSkipped(SourceRange Range, SourceLocation EndifLoc) override;
  82
  83   void HandleEmptyline(SourceRange Range) override;
  84
  85   bool HandleComment(Preprocessor &PP, SourceRange Range) override;
  86
  87   void updateNextTokLoc(SourceLocation Loc);
  88 };
  89
  90 namespace CodeGen {
  91
  92 class CodeGenModule;
  93
  94 /// Organizes the cross-function state that is used while generating
  95 /// code coverage mapping data.
  96 class CoverageMappingModuleGen {
  97   /// Information needed to emit a coverage record for a function.
  98   struct FunctionInfo {
  99     uint64_t NameHash;
 100     uint64_t FuncHash;
 101     std::string CoverageMapping;
 102     bool IsUsed;
 103   };
 104
 105   CodeGenModule &CGM;
 106   CoverageSourceInfo &SourceInfo;
 107   llvm::SmallDenseMap<const FileEntry *, unsigned, 8> FileEntries;
 108   std::vector<llvm::Constant *> FunctionNames;
 109   std::vector<FunctionInfo> FunctionRecords;
 110   std::map<std::string, std::string> CoveragePrefixMap;
 111
 112   std::string getCurrentDirname();
 113   std::string normalizeFilename(StringRef Filename);
 114
 115   /// Emit a function record.
 116   void emitFunctionMappingRecord(const FunctionInfo &Info,
 117                                  uint64_t FilenamesRef);
 118
 119 public:
 120   static CoverageSourceInfo *setUpCoverageCallbacks(Preprocessor &PP);
 121
 122   CoverageMappingModuleGen(CodeGenModule &CGM, CoverageSourceInfo &SourceInfo);
 123
 124   CoverageSourceInfo &getSourceInfo() const {
 125     return SourceInfo;
 126   }
 127
 128   /// Add a function's coverage mapping record to the collection of the
 129   /// function mapping records.
 130   void addFunctionMappingRecord(llvm::GlobalVariable *FunctionName,
 131                                 StringRef FunctionNameValue,
 132                                 uint64_t FunctionHash,
 133                                 const std::string &CoverageMapping,
 134                                 bool IsUsed = true);
 135
 136   /// Emit the coverage mapping data for a translation unit.
 137   void emit();
 138
 139   /// Return the coverage mapping translation unit file id
 140   /// for the given file.
 141   unsigned getFileID(const FileEntry *File);
 142
 143   /// Return an interface into CodeGenModule.
 144   CodeGenModule &getCodeGenModule() { return CGM; }
 145 };
 146
 147 /// Organizes the per-function state that is used while generating
 148 /// code coverage mapping data.
 149 class CoverageMappingGen {
 150   CoverageMappingModuleGen &CVM;
 151   SourceManager &SM;
 152   const LangOptions &LangOpts;
 153   llvm::DenseMap<const Stmt *, unsigned> *CounterMap;
 154
 155 public:
 156   CoverageMappingGen(CoverageMappingModuleGen &CVM, SourceManager &SM,
 157                      const LangOptions &LangOpts)
 158       : CVM(CVM), SM(SM), LangOpts(LangOpts), CounterMap(nullptr) {}
 159
 160   CoverageMappingGen(CoverageMappingModuleGen &CVM, SourceManager &SM,
 161                      const LangOptions &LangOpts,
 162                      llvm::DenseMap<const Stmt *, unsigned> *CounterMap)
 163       : CVM(CVM), SM(SM), LangOpts(LangOpts), CounterMap(CounterMap) {}
 164
 165   /// Emit the coverage mapping data which maps the regions of
 166   /// code to counters that will be used to find the execution
 167   /// counts for those regions.
 168   void emitCounterMapping(const Decl *D, llvm::raw_ostream &OS);
 169
 170   /// Emit the coverage mapping data for an unused function.
 171   /// It creates mapping regions with the counter of zero.
 172   void emitEmptyMapping(const Decl *D, llvm::raw_ostream &OS);
 173 };
 174
 175 } // end namespace CodeGen
 176 } // end namespace clang
 177
 178 #endif