1 //===----- llvm/CodeGen/GlobalISel/LostDebugLocObserver.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 /// \file
9 /// Tracks DebugLocs between checkpoints and verifies that they are transferred.
10 ///
11 //===----------------------------------------------------------------------===//
12 #ifndef LLVM_CODEGEN_GLOBALISEL_LOSTDEBUGLOCOBSERVER_H
13 #define LLVM_CODEGEN_GLOBALISEL_LOSTDEBUGLOCOBSERVER_H
14 
15 #include "llvm/ADT/SmallSet.h"
16 #include "llvm/CodeGen/GlobalISel/GISelChangeObserver.h"
17 
18 namespace llvm {
19 class LostDebugLocObserver : public GISelChangeObserver {
20   StringRef DebugType;
21   SmallSet<DebugLoc, 4> LostDebugLocs;
22   SmallPtrSet<MachineInstr *, 4> PotentialMIsForDebugLocs;
23   unsigned NumLostDebugLocs = 0;
24 
25 public:
26   LostDebugLocObserver(StringRef DebugType) : DebugType(DebugType) {}
27 
28   unsigned getNumLostDebugLocs() const { return NumLostDebugLocs; }
29 
30   /// Call this to indicate that it's a good point to assess whether locations
31   /// have been lost. Typically this will be when a logical change has been
32   /// completed such as the caller has finished replacing some instructions with
33   /// alternatives. When CheckDebugLocs is true, the locations will be checked
34   /// to see if any have been lost since the last checkpoint. When
35   /// CheckDebugLocs is false, it will just reset ready for the next checkpoint
36   /// without checking anything. This can be helpful to limit the detection to
37   /// easy-to-fix portions of an algorithm before allowing more difficult ones.
38   void checkpoint(bool CheckDebugLocs = true);
39 
40   void createdInstr(MachineInstr &MI) override;
41   void erasingInstr(MachineInstr &MI) override;
42   void changingInstr(MachineInstr &MI) override;
43   void changedInstr(MachineInstr &MI) override;
44 
45 private:
46   void analyzeDebugLocations();
47 };
48 
49 } // namespace llvm
50 #endif // LLVM_CODEGEN_GLOBALISEL_LOSTDEBUGLOCOBSERVER_H
51