1 //===- DebugInfo.h - Debug Information Helpers ------------------*- 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 defines a bunch of datatypes that are useful for creating and
11 // walking debug info in LLVM IR form. They essentially provide wrappers around
12 // the information in the global variables that's needed when constructing the
13 // DWARF information.
14 //
15 //===----------------------------------------------------------------------===//
16 
17 #ifndef LLVM_IR_DEBUGINFO_H
18 #define LLVM_IR_DEBUGINFO_H
19 
20 #include "llvm/ADT/DenseMap.h"
21 #include "llvm/ADT/SmallPtrSet.h"
22 #include "llvm/ADT/SmallVector.h"
23 #include "llvm/ADT/StringRef.h"
24 #include "llvm/ADT/iterator_range.h"
25 #include "llvm/IR/DebugInfoMetadata.h"
26 #include "llvm/Support/Casting.h"
27 #include "llvm/Support/Dwarf.h"
28 #include "llvm/Support/ErrorHandling.h"
29 #include <iterator>
30 
31 namespace llvm {
32 class Module;
33 class DbgDeclareInst;
34 class DbgValueInst;
35 
36 /// \brief Maps from type identifier to the actual MDNode.
37 typedef DenseMap<const MDString *, DIType *> DITypeIdentifierMap;
38 
39 /// \brief Find subprogram that is enclosing this scope.
40 DISubprogram *getDISubprogram(const MDNode *Scope);
41 
42 /// \brief Find debug info for a given function.
43 ///
44 /// \returns a valid subprogram, if found. Otherwise, return \c nullptr.
45 DISubprogram *getDISubprogram(const Function *F);
46 
47 /// \brief Generate map by visiting all retained types.
48 DITypeIdentifierMap generateDITypeIdentifierMap(const NamedMDNode *CU_Nodes);
49 
50 /// \brief Strip debug info in the module if it exists.
51 ///
52 /// To do this, we remove all calls to the debugger intrinsics and any named
53 /// metadata for debugging. We also remove debug locations for instructions.
54 /// Return true if module is modified.
55 bool StripDebugInfo(Module &M);
56 bool stripDebugInfo(Function &F);
57 
58 /// \brief Return Debug Info Metadata Version by checking module flags.
59 unsigned getDebugMetadataVersionFromModule(const Module &M);
60 
61 /// \brief Utility to find all debug info in a module.
62 ///
63 /// DebugInfoFinder tries to list all debug info MDNodes used in a module. To
64 /// list debug info MDNodes used by an instruction, DebugInfoFinder uses
65 /// processDeclare, processValue and processLocation to handle DbgDeclareInst,
66 /// DbgValueInst and DbgLoc attached to instructions. processModule will go
67 /// through all DICompileUnits in llvm.dbg.cu and list debug info MDNodes
68 /// used by the CUs.
69 class DebugInfoFinder {
70 public:
DebugInfoFinder()71   DebugInfoFinder() : TypeMapInitialized(false) {}
72 
73   /// \brief Process entire module and collect debug info anchors.
74   void processModule(const Module &M);
75 
76   /// \brief Process DbgDeclareInst.
77   void processDeclare(const Module &M, const DbgDeclareInst *DDI);
78   /// \brief Process DbgValueInst.
79   void processValue(const Module &M, const DbgValueInst *DVI);
80   /// \brief Process debug info location.
81   void processLocation(const Module &M, const DILocation *Loc);
82 
83   /// \brief Clear all lists.
84   void reset();
85 
86 private:
87   void InitializeTypeMap(const Module &M);
88 
89   void processType(DIType *DT);
90   void processSubprogram(DISubprogram *SP);
91   void processScope(DIScope *Scope);
92   bool addCompileUnit(DICompileUnit *CU);
93   bool addGlobalVariable(DIGlobalVariable *DIG);
94   bool addSubprogram(DISubprogram *SP);
95   bool addType(DIType *DT);
96   bool addScope(DIScope *Scope);
97 
98 public:
99   typedef SmallVectorImpl<DICompileUnit *>::const_iterator
100       compile_unit_iterator;
101   typedef SmallVectorImpl<DISubprogram *>::const_iterator subprogram_iterator;
102   typedef SmallVectorImpl<DIGlobalVariable *>::const_iterator
103       global_variable_iterator;
104   typedef SmallVectorImpl<DIType *>::const_iterator type_iterator;
105   typedef SmallVectorImpl<DIScope *>::const_iterator scope_iterator;
106 
compile_units()107   iterator_range<compile_unit_iterator> compile_units() const {
108     return make_range(CUs.begin(), CUs.end());
109   }
110 
subprograms()111   iterator_range<subprogram_iterator> subprograms() const {
112     return make_range(SPs.begin(), SPs.end());
113   }
114 
global_variables()115   iterator_range<global_variable_iterator> global_variables() const {
116     return make_range(GVs.begin(), GVs.end());
117   }
118 
types()119   iterator_range<type_iterator> types() const {
120     return make_range(TYs.begin(), TYs.end());
121   }
122 
scopes()123   iterator_range<scope_iterator> scopes() const {
124     return make_range(Scopes.begin(), Scopes.end());
125   }
126 
compile_unit_count()127   unsigned compile_unit_count() const { return CUs.size(); }
global_variable_count()128   unsigned global_variable_count() const { return GVs.size(); }
subprogram_count()129   unsigned subprogram_count() const { return SPs.size(); }
type_count()130   unsigned type_count() const { return TYs.size(); }
scope_count()131   unsigned scope_count() const { return Scopes.size(); }
132 
133 private:
134   SmallVector<DICompileUnit *, 8> CUs;
135   SmallVector<DISubprogram *, 8> SPs;
136   SmallVector<DIGlobalVariable *, 8> GVs;
137   SmallVector<DIType *, 8> TYs;
138   SmallVector<DIScope *, 8> Scopes;
139   SmallPtrSet<const MDNode *, 64> NodesSeen;
140   DITypeIdentifierMap TypeIdentifierMap;
141 
142   /// \brief Specify if TypeIdentifierMap is initialized.
143   bool TypeMapInitialized;
144 };
145 
146 } // end namespace llvm
147 
148 #endif
149