1 //===-- PdbSymUid.h ---------------------------------------------*- 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 // A unique identification scheme for Pdb records.
9 // The scheme is to partition a 64-bit integer into an 8-bit tag field, which
10 // will contain some value from the PDB_SymType enumeration.  The format of the
11 // other 48-bits depend on the tag, but must be sufficient to locate the
12 // corresponding entry in the underlying PDB file quickly.  For example, for
13 // a compile unit, we use 2 bytes to represent the index, which allows fast
14 // access to the compile unit's information.
15 //===----------------------------------------------------------------------===//
16 
17 #ifndef LLDB_SOURCE_PLUGINS_SYMBOLFILE_NATIVEPDB_PDBSYMUID_H
18 #define LLDB_SOURCE_PLUGINS_SYMBOLFILE_NATIVEPDB_PDBSYMUID_H
19 
20 #include "llvm/DebugInfo/CodeView/SymbolRecord.h"
21 #include "llvm/DebugInfo/PDB/PDBTypes.h"
22 #include "llvm/Support/Compiler.h"
23 
24 #include "lldb/Utility/LLDBAssert.h"
25 #include "lldb/lldb-types.h"
26 
27 namespace lldb_private {
28 namespace npdb {
29 
30 enum class PdbSymUidKind : uint8_t {
31   Compiland,
32   CompilandSym,
33   PublicSym,
34   GlobalSym,
35   Type,
36   FieldListMember
37 };
38 
39 struct PdbCompilandId {
40   // 0-based index of module in PDB
41   uint16_t modi;
42 };
43 
44 struct PdbCompilandSymId {
45   PdbCompilandSymId() = default;
46   PdbCompilandSymId(uint16_t modi, uint32_t offset)
47       : modi(modi), offset(offset) {}
48   // 0-based index of module in PDB
49   uint16_t modi = 0;
50 
51   // Offset of symbol's record in module stream.  This is
52   // offset by 4 from the CVSymbolArray's notion of offset
53   // due to the debug magic at the beginning of the stream.
54   uint32_t offset = 0;
55 };
56 
57 struct PdbGlobalSymId {
58   PdbGlobalSymId() = default;
59   PdbGlobalSymId(uint32_t offset, bool is_public)
60       : offset(offset), is_public(is_public) {}
61 
62   // Offset of symbol's record in globals or publics stream.
63   uint32_t offset = 0;
64 
65   // True if this symbol is in the public stream, false if it's in the globals
66   // stream.
67   bool is_public = false;
68 };
69 
70 struct PdbTypeSymId {
71   PdbTypeSymId() = default;
72   PdbTypeSymId(llvm::codeview::TypeIndex index, bool is_ipi = false)
73       : index(index), is_ipi(is_ipi) {}
74 
75   // The index of the of the type in the TPI or IPI stream.
76   llvm::codeview::TypeIndex index;
77 
78   // True if this symbol comes from the IPI stream, false if it's from the TPI
79   // stream.
80   bool is_ipi = false;
81 };
82 
83 struct PdbFieldListMemberId {
84   // The TypeIndex of the LF_FIELDLIST record.
85   llvm::codeview::TypeIndex index;
86 
87   // The offset from the beginning of the LF_FIELDLIST record to this record.
88   uint16_t offset = 0;
89 };
90 
91 class PdbSymUid {
92   uint64_t m_repr = 0;
93 
94 public:
95   PdbSymUid() = default;
96   PdbSymUid(uint64_t repr) : m_repr(repr) {}
97   PdbSymUid(const PdbCompilandId &cid);
98   PdbSymUid(const PdbCompilandSymId &csid);
99   PdbSymUid(const PdbGlobalSymId &gsid);
100   PdbSymUid(const PdbTypeSymId &tsid);
101   PdbSymUid(const PdbFieldListMemberId &flmid);
102 
103   uint64_t toOpaqueId() const { return m_repr; }
104 
105   PdbSymUidKind kind() const;
106 
107   PdbCompilandId asCompiland() const;
108   PdbCompilandSymId asCompilandSym() const;
109   PdbGlobalSymId asGlobalSym() const;
110   PdbTypeSymId asTypeSym() const;
111   PdbFieldListMemberId asFieldListMember() const;
112 };
113 
114 template <typename T> uint64_t toOpaqueUid(const T &cid) {
115   return PdbSymUid(cid).toOpaqueId();
116 }
117 
118 struct SymbolAndUid {
119   llvm::codeview::CVSymbol sym;
120   PdbSymUid uid;
121 };
122 } // namespace npdb
123 } // namespace lldb_private
124 
125 #endif
126