include/llvm/CodeGen/RegisterUsageInfo.h

   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/Pass.h"
  25 #include <cstdint>
  26 #include <vector>
  27
  28 namespace llvm {
  29
  30 class Function;
  31 class LLVMTargetMachine;
  32
  33 class PhysicalRegisterUsageInfo : public ImmutablePass {
  34 public:
  35   static char ID;
  36
  37   PhysicalRegisterUsageInfo() : ImmutablePass(ID) {
  38     PassRegistry &Registry = *PassRegistry::getPassRegistry();
  39     initializePhysicalRegisterUsageInfoPass(Registry);
  40   }
  41
  42   /// Set TargetMachine which is used to print analysis.
  43   void setTargetMachine(const LLVMTargetMachine &TM);
  44
  45   bool doInitialization(Module &M) override;
  46
  47   bool doFinalization(Module &M) override;
  48
  49   /// To store RegMask for given Function *.
  50   void storeUpdateRegUsageInfo(const Function &FP,
  51                                ArrayRef<uint32_t> RegMask);
  52
  53   /// To query stored RegMask for given Function *, it will returns ane empty
  54   /// array if function is not known.
  55   ArrayRef<uint32_t> getRegUsageInfo(const Function &FP);
  56
  57   void print(raw_ostream &OS, const Module *M = nullptr) const override;
  58
  59 private:
  60   /// A Dense map from Function * to RegMask.
  61   /// In RegMask 0 means register used (clobbered) by function.
  62   /// and 1 means content of register will be preserved around function call.
  63   DenseMap<const Function *, std::vector<uint32_t>> RegMasks;
  64
  65   const LLVMTargetMachine *TM;
  66 };
  67
  68 } // end namespace llvm
  69
  70 #endif // LLVM_CODEGEN_PHYSICALREGISTERUSAGEINFO_H