RegisterUsageInfo.h revision c9cc9e7d29b8970d8ddb734c88fb62d01e0b7279 
1//==- RegisterUsageInfo.h - Register Usage Informartion Storage --*- C++ -*-==//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9/// \file
10/// This pass is required to take advantage of the interprocedural register
11/// allocation infrastructure.
12///
13/// This pass is simple immutable pass which keeps RegMasks (calculated based on
14/// actual register allocation) for functions in a module and provides simple
15/// API to query this information.
16///
17//===----------------------------------------------------------------------===//
18
19#ifndef LLVM_CODEGEN_PHYSICALREGISTERUSAGEINFO_H
20#define LLVM_CODEGEN_PHYSICALREGISTERUSAGEINFO_H
21
22#include "llvm/ADT/DenseMap.h"
23#include "llvm/Pass.h"
24#include <cstdint>
25#include <vector>
26
27namespace llvm {
28
29class Function;
30class TargetMachine;
31
32class PhysicalRegisterUsageInfo : public ImmutablePass {
33  virtual void anchor();
34
35public:
36  static char ID;
37
38  PhysicalRegisterUsageInfo() : ImmutablePass(ID) {
39    PassRegistry &Registry = *PassRegistry::getPassRegistry();
40    initializePhysicalRegisterUsageInfoPass(Registry);
41  }
42
43  void getAnalysisUsage(AnalysisUsage &AU) const override {
44    AU.setPreservesAll();
45  }
46
47  /// To set TargetMachine *, which is used to print
48  /// analysis when command line option -print-regusage is used.
49  void setTargetMachine(const TargetMachine *TM_) { TM = TM_; }
50
51  bool doInitialization(Module &M) override;
52
53  bool doFinalization(Module &M) override;
54
55  /// To store RegMask for given Function *.
56  void storeUpdateRegUsageInfo(const Function *FP,
57                               std::vector<uint32_t> RegMask);
58
59  /// To query stored RegMask for given Function *, it will return nullptr if
60  /// function is not known.
61  const std::vector<uint32_t> *getRegUsageInfo(const Function *FP);
62
63  void print(raw_ostream &OS, const Module *M = nullptr) const override;
64
65private:
66  /// A Dense map from Function * to RegMask.
67  /// In RegMask 0 means register used (clobbered) by function.
68  /// and 1 means content of register will be preserved around function call.
69  DenseMap<const Function *, std::vector<uint32_t>> RegMasks;
70
71  const TargetMachine *TM;
72};
73
74} // end namespace llvm
75
76#endif // LLVM_CODEGEN_PHYSICALREGISTERUSAGEINFO_H
77