1 //===- ReachableCode.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 // A flow-sensitive, path-insensitive analysis of unreachable code.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_CLANG_ANALYSIS_ANALYSES_REACHABLECODE_H
14 #define LLVM_CLANG_ANALYSIS_ANALYSES_REACHABLECODE_H
15 
16 #include "clang/Basic/SourceLocation.h"
17 
18 //===----------------------------------------------------------------------===//
19 // Forward declarations.
20 //===----------------------------------------------------------------------===//
21 
22 namespace llvm {
23   class BitVector;
24 }
25 
26 namespace clang {
27   class AnalysisDeclContext;
28   class CFGBlock;
29   class Preprocessor;
30 }
31 
32 //===----------------------------------------------------------------------===//
33 // API.
34 //===----------------------------------------------------------------------===//
35 
36 namespace clang {
37 namespace reachable_code {
38 
39 /// Classifications of unreachable code.
40 enum UnreachableKind {
41   UK_Return,
42   UK_Break,
43   UK_Loop_Increment,
44   UK_Other
45 };
46 
47 class Callback {
48   virtual void anchor();
49 public:
~Callback()50   virtual ~Callback() {}
51   virtual void HandleUnreachable(UnreachableKind UK,
52                                  SourceLocation L,
53                                  SourceRange ConditionVal,
54                                  SourceRange R1,
55                                  SourceRange R2) = 0;
56 };
57 
58 /// ScanReachableFromBlock - Mark all blocks reachable from Start.
59 /// Returns the total number of blocks that were marked reachable.
60 unsigned ScanReachableFromBlock(const CFGBlock *Start,
61                                 llvm::BitVector &Reachable);
62 
63 void FindUnreachableCode(AnalysisDeclContext &AC, Preprocessor &PP,
64                          Callback &CB);
65 
66 }} // end namespace clang::reachable_code
67 
68 #endif
69