• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 //===-- llvm/lib/CodeGen/AsmPrinter/WinCodeViewLineTables.h ----*- 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 writing line tables info into COFF files.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_WINCODEVIEWLINETABLES_H
15 #define LLVM_LIB_CODEGEN_ASMPRINTER_WINCODEVIEWLINETABLES_H
16 
17 #include "AsmPrinterHandler.h"
18 #include "llvm/ADT/DenseMap.h"
19 #include "llvm/ADT/StringMap.h"
20 #include "llvm/ADT/StringRef.h"
21 #include "llvm/CodeGen/AsmPrinter.h"
22 #include "llvm/CodeGen/LexicalScopes.h"
23 #include "llvm/CodeGen/MachineFunction.h"
24 #include "llvm/CodeGen/MachineModuleInfo.h"
25 #include "llvm/IR/DebugInfo.h"
26 #include "llvm/IR/DebugLoc.h"
27 #include "llvm/MC/MCStreamer.h"
28 #include "llvm/Target/TargetLoweringObjectFile.h"
29 
30 namespace llvm {
31 /// \brief Collects and handles line tables information in a CodeView format.
32 class LLVM_LIBRARY_VISIBILITY WinCodeViewLineTables : public AsmPrinterHandler {
33   AsmPrinter *Asm;
34   DebugLoc PrevInstLoc;
35 
36   // For each function, store a vector of labels to its instructions, as well as
37   // to the end of the function.
38   struct FunctionInfo {
39     SmallVector<MCSymbol *, 10> Instrs;
40     MCSymbol *End;
FunctionInfoFunctionInfo41     FunctionInfo() : End(nullptr) {}
42   } *CurFn;
43 
44   typedef DenseMap<const Function *, FunctionInfo> FnDebugInfoTy;
45   FnDebugInfoTy FnDebugInfo;
46   // Store the functions we've visited in a vector so we can maintain a stable
47   // order while emitting subsections.
48   SmallVector<const Function *, 10> VisitedFunctions;
49 
50   // InstrInfoTy - Holds the Filename:LineNumber information for every
51   // instruction with a unique debug location.
52   struct InstrInfoTy {
53     StringRef Filename;
54     unsigned LineNumber;
55     unsigned ColumnNumber;
56 
InstrInfoTyInstrInfoTy57     InstrInfoTy() : LineNumber(0), ColumnNumber(0) {}
58 
InstrInfoTyInstrInfoTy59     InstrInfoTy(StringRef Filename, unsigned LineNumber, unsigned ColumnNumber)
60         : Filename(Filename), LineNumber(LineNumber),
61           ColumnNumber(ColumnNumber) {}
62   };
63   DenseMap<MCSymbol *, InstrInfoTy> InstrInfo;
64 
65   // FileNameRegistry - Manages filenames observed while generating debug info
66   // by filtering out duplicates and bookkeeping the offsets in the string
67   // table to be generated.
68   struct FileNameRegistryTy {
69     SmallVector<StringRef, 10> Filenames;
70     struct PerFileInfo {
71       size_t FilenameID, StartOffset;
72     };
73     StringMap<PerFileInfo> Infos;
74 
75     // The offset in the string table where we'll write the next unique
76     // filename.
77     size_t LastOffset;
78 
FileNameRegistryTyFileNameRegistryTy79     FileNameRegistryTy() {
80       clear();
81     }
82 
83     // Add Filename to the registry, if it was not observed before.
addFileNameRegistryTy84     void add(StringRef Filename) {
85       if (Infos.count(Filename))
86         return;
87       size_t OldSize = Infos.size();
88       Infos[Filename].FilenameID = OldSize;
89       Infos[Filename].StartOffset = LastOffset;
90       LastOffset += Filename.size() + 1;
91       Filenames.push_back(Filename);
92     }
93 
clearFileNameRegistryTy94     void clear() {
95       LastOffset = 1;
96       Infos.clear();
97       Filenames.clear();
98     }
99   } FileNameRegistry;
100 
101   typedef std::map<std::pair<StringRef, StringRef>, std::string>
102       DirAndFilenameToFilepathMapTy;
103   DirAndFilenameToFilepathMapTy DirAndFilenameToFilepathMap;
104   StringRef getFullFilepath(const MDNode *S);
105 
106   void maybeRecordLocation(DebugLoc DL, const MachineFunction *MF);
107 
clear()108   void clear() {
109     assert(CurFn == nullptr);
110     FileNameRegistry.clear();
111     InstrInfo.clear();
112   }
113 
114   void emitDebugInfoForFunction(const Function *GV);
115 
116 public:
117   WinCodeViewLineTables(AsmPrinter *Asm);
118 
setSymbolSize(const llvm::MCSymbol *,uint64_t)119   void setSymbolSize(const llvm::MCSymbol *, uint64_t) override {}
120 
121   /// \brief Emit the COFF section that holds the line table information.
122   void endModule() override;
123 
124   /// \brief Gather pre-function debug information.
125   void beginFunction(const MachineFunction *MF) override;
126 
127   /// \brief Gather post-function debug information.
128   void endFunction(const MachineFunction *) override;
129 
130   /// \brief Process beginning of an instruction.
131   void beginInstruction(const MachineInstr *MI) override;
132 
133   /// \brief Process end of an instruction.
endInstruction()134   void endInstruction() override {}
135 };
136 } // End of namespace llvm
137 
138 #endif
139