1 //===----- MIRFSDiscriminator.h: MIR FS Discriminator Support --0-- 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 // This file contains the supporting functions for adding Machine level IR
10 // Flow Sensitive discriminators to the instruction debug information. With
11 // this, a cloned machine instruction in a different MachineBasicBlock will
12 // have its own discriminator value. This is done in a MIRAddFSDiscriminators
13 // pass.
14 //
15 //===----------------------------------------------------------------------===//
16 
17 #ifndef LLVM_CODEGEN_MIRFSDISCRIMINATOR_H
18 #define LLVM_CODEGEN_MIRFSDISCRIMINATOR_H
19 
20 #include "llvm/ADT/StringRef.h"
21 #include "llvm/CodeGen/MachineFunction.h"
22 #include "llvm/CodeGen/MachineFunctionPass.h"
23 #include "llvm/Support/Discriminator.h"
24 
25 #include <cassert>
26 #include <cstdint>
27 
28 namespace llvm {
29 class MachineFunction;
30 
31 using namespace sampleprof;
32 class MIRAddFSDiscriminators : public MachineFunctionPass {
33   MachineFunction *MF = nullptr;
34   FSDiscriminatorPass Pass;
35   unsigned LowBit;
36   unsigned HighBit;
37 
38 public:
39   static char ID;
40   /// PassNum is the sequence number this pass is called, start from 1.
41   MIRAddFSDiscriminators(FSDiscriminatorPass P = FSDiscriminatorPass::Pass1)
42       : MachineFunctionPass(ID), Pass(P) {
43     LowBit = getFSPassBitBegin(P);
44     HighBit = getFSPassBitEnd(P);
45     assert(LowBit < HighBit && "HighBit needs to be greater than Lowbit");
46   }
47 
48   StringRef getPassName() const override {
49     return "Add FS discriminators in MIR";
50   }
51 
52   /// getNumFSBBs() - Return the number of machine BBs that have FS samples.
53   unsigned getNumFSBBs();
54 
55   /// getNumFSSamples() - Return the number of samples that have flow sensitive
56   /// values.
57   uint64_t getNumFSSamples();
58 
59   /// getMachineFunction - Return the current machine function.
60   const MachineFunction *getMachineFunction() const { return MF; }
61 
62 private:
63   bool runOnMachineFunction(MachineFunction &) override;
64 };
65 
66 } // namespace llvm
67 
68 #endif // LLVM_CODEGEN_MIRFSDISCRIMINATOR_H
69