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 "llvm/ADT/DenseMap.h"
20 #include "llvm/IR/GlobalValue.h"
21 #include "llvm/Support/raw_ostream.h"
22 
23 namespace clang {
24 
25 class LangOptions;
26 class SourceManager;
27 class FileEntry;
28 class Preprocessor;
29 class Decl;
30 class Stmt;
31 
32 /// Stores additional source code information like skipped ranges which
33 /// is required by the coverage mapping generator and is obtained from
34 /// the preprocessor.
35 class CoverageSourceInfo : public PPCallbacks {
36   std::vector<SourceRange> SkippedRanges;
37 public:
getSkippedRanges()38   ArrayRef<SourceRange> getSkippedRanges() const { return SkippedRanges; }
39 
40   void SourceRangeSkipped(SourceRange Range, SourceLocation EndifLoc) override;
41 };
42 
43 namespace CodeGen {
44 
45 class CodeGenModule;
46 
47 /// Organizes the cross-function state that is used while generating
48 /// code coverage mapping data.
49 class CoverageMappingModuleGen {
50   /// Information needed to emit a coverage record for a function.
51   struct FunctionInfo {
52     uint64_t NameHash;
53     uint64_t FuncHash;
54     std::string CoverageMapping;
55     bool IsUsed;
56   };
57 
58   CodeGenModule &CGM;
59   CoverageSourceInfo &SourceInfo;
60   llvm::SmallDenseMap<const FileEntry *, unsigned, 8> FileEntries;
61   std::vector<llvm::Constant *> FunctionNames;
62   std::vector<FunctionInfo> FunctionRecords;
63 
64   /// Emit a function record.
65   void emitFunctionMappingRecord(const FunctionInfo &Info,
66                                  uint64_t FilenamesRef);
67 
68 public:
CoverageMappingModuleGen(CodeGenModule & CGM,CoverageSourceInfo & SourceInfo)69   CoverageMappingModuleGen(CodeGenModule &CGM, CoverageSourceInfo &SourceInfo)
70       : CGM(CGM), SourceInfo(SourceInfo) {}
71 
getSourceInfo()72   CoverageSourceInfo &getSourceInfo() const {
73     return SourceInfo;
74   }
75 
76   /// Add a function's coverage mapping record to the collection of the
77   /// function mapping records.
78   void addFunctionMappingRecord(llvm::GlobalVariable *FunctionName,
79                                 StringRef FunctionNameValue,
80                                 uint64_t FunctionHash,
81                                 const std::string &CoverageMapping,
82                                 bool IsUsed = true);
83 
84   /// Emit the coverage mapping data for a translation unit.
85   void emit();
86 
87   /// Return the coverage mapping translation unit file id
88   /// for the given file.
89   unsigned getFileID(const FileEntry *File);
90 };
91 
92 /// Organizes the per-function state that is used while generating
93 /// code coverage mapping data.
94 class CoverageMappingGen {
95   CoverageMappingModuleGen &CVM;
96   SourceManager &SM;
97   const LangOptions &LangOpts;
98   llvm::DenseMap<const Stmt *, unsigned> *CounterMap;
99 
100 public:
CoverageMappingGen(CoverageMappingModuleGen & CVM,SourceManager & SM,const LangOptions & LangOpts)101   CoverageMappingGen(CoverageMappingModuleGen &CVM, SourceManager &SM,
102                      const LangOptions &LangOpts)
103       : CVM(CVM), SM(SM), LangOpts(LangOpts), CounterMap(nullptr) {}
104 
CoverageMappingGen(CoverageMappingModuleGen & CVM,SourceManager & SM,const LangOptions & LangOpts,llvm::DenseMap<const Stmt *,unsigned> * CounterMap)105   CoverageMappingGen(CoverageMappingModuleGen &CVM, SourceManager &SM,
106                      const LangOptions &LangOpts,
107                      llvm::DenseMap<const Stmt *, unsigned> *CounterMap)
108       : CVM(CVM), SM(SM), LangOpts(LangOpts), CounterMap(CounterMap) {}
109 
110   /// Emit the coverage mapping data which maps the regions of
111   /// code to counters that will be used to find the execution
112   /// counts for those regions.
113   void emitCounterMapping(const Decl *D, llvm::raw_ostream &OS);
114 
115   /// Emit the coverage mapping data for an unused function.
116   /// It creates mapping regions with the counter of zero.
117   void emitEmptyMapping(const Decl *D, llvm::raw_ostream &OS);
118 };
119 
120 } // end namespace CodeGen
121 } // end namespace clang
122 
123 #endif
124