RegisterUsageInfo.h revision 360784 
1//==- RegisterUsageInfo.h - Register Usage Informartion Storage --*- 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/// This pass is required to take advantage of the interprocedural register
10/// allocation infrastructure.
11///
12/// This pass is simple immutable pass which keeps RegMasks (calculated based on
13/// actual register allocation) for functions in a module and provides simple
14/// API to query this information.
15///
16//===----------------------------------------------------------------------===//
17
18#ifndef LLVM_CODEGEN_PHYSICALREGISTERUSAGEINFO_H
19#define LLVM_CODEGEN_PHYSICALREGISTERUSAGEINFO_H
20
21#include "llvm/ADT/ArrayRef.h"
22#include "llvm/ADT/DenseMap.h"
23#include "llvm/IR/Instructions.h"
24#include "llvm/InitializePasses.h"
25#include "llvm/Pass.h"
26#include <cstdint>
27#include <vector>
28
29namespace llvm {
30
31class Function;
32class LLVMTargetMachine;
33
34class PhysicalRegisterUsageInfo : public ImmutablePass {
35public:
36  static char ID;
37
38  PhysicalRegisterUsageInfo() : ImmutablePass(ID) {
39    PassRegistry &Registry = *PassRegistry::getPassRegistry();
40    initializePhysicalRegisterUsageInfoPass(Registry);
41  }
42
43  /// Set TargetMachine which is used to print analysis.
44  void setTargetMachine(const LLVMTargetMachine &TM);
45
46  bool doInitialization(Module &M) override;
47
48  bool doFinalization(Module &M) override;
49
50  /// To store RegMask for given Function *.
51  void storeUpdateRegUsageInfo(const Function &FP,
52                               ArrayRef<uint32_t> RegMask);
53
54  /// To query stored RegMask for given Function *, it will returns ane empty
55  /// array if function is not known.
56  ArrayRef<uint32_t> getRegUsageInfo(const Function &FP);
57
58  void print(raw_ostream &OS, const Module *M = nullptr) const override;
59
60private:
61  /// A Dense map from Function * to RegMask.
62  /// In RegMask 0 means register used (clobbered) by function.
63  /// and 1 means content of register will be preserved around function call.
64  DenseMap<const Function *, std::vector<uint32_t>> RegMasks;
65
66  const LLVMTargetMachine *TM;
67};
68
69} // end namespace llvm
70
71#endif // LLVM_CODEGEN_PHYSICALREGISTERUSAGEINFO_H
72