1 //===- TypeReferenceTracker.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 
9 #ifndef LLVM_TOOLS_LLVMPDBDUMP_TYPEREFERENCETRACKER_H
10 #define LLVM_TOOLS_LLVMPDBDUMP_TYPEREFERENCETRACKER_H
11 
12 #include "InputFile.h"
13 
14 #include "llvm/ADT/BitVector.h"
15 #include "llvm/ADT/Optional.h"
16 #include "llvm/ADT/SmallVector.h"
17 #include "llvm/DebugInfo/CodeView/CVRecord.h"
18 #include "llvm/DebugInfo/CodeView/TypeIndex.h"
19 #include "llvm/DebugInfo/CodeView/TypeIndexDiscovery.h"
20 #include "llvm/Support/Error.h"
21 
22 namespace llvm {
23 namespace pdb {
24 
25 class TpiStream;
26 
27 /// Maintains bitvector to track whether a type was referenced by a symbol
28 /// record.
29 class TypeReferenceTracker {
30 public:
31   TypeReferenceTracker(InputFile &File);
32 
33   // Do the work of marking referenced types.
34   void mark();
35 
36   // Return true if a symbol record transitively references this type.
37   bool isTypeReferenced(codeview::TypeIndex TI) {
38     return TI.toArrayIndex() <= NumTypeRecords &&
39            TypeReferenced.test(TI.toArrayIndex());
40   }
41 
42 private:
43   void addTypeRefsFromSymbol(const codeview::CVSymbol &Sym);
44 
45   // Mark types on this list as referenced.
46   void addReferencedTypes(ArrayRef<uint8_t> RecData,
47                           ArrayRef<codeview::TiReference> Refs);
48 
49   // Consume all types on the worklist.
50   void markReferencedTypes();
51 
52   void addOneTypeRef(codeview::TiRefKind RefKind, codeview::TypeIndex RefTI);
53 
54   InputFile &File;
55   codeview::LazyRandomTypeCollection &Types;
56   codeview::LazyRandomTypeCollection *Ids = nullptr;
57   TpiStream *Tpi = nullptr;
58   BitVector TypeReferenced;
59   BitVector IdReferenced;
60   SmallVector<std::pair<codeview::TiRefKind, codeview::TypeIndex>, 10>
61       RefWorklist;
62   uint32_t NumTypeRecords = 0;
63   uint32_t NumIdRecords = 0;
64 };
65 
66 } // namespace pdb
67 } // namespace llvm
68 
69 #endif // LLVM_TOOLS_LLVMPDBDUMP_TYPEREFERENCETRACKER_H
70