llvm/lib/CodeGen/RegAllocPriorityAdvisor.h

   1 //===- RegAllocPriorityAdvisor.h - live ranges priority advisor -*- 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 #ifndef LLVM_CODEGEN_REGALLOCPRIORITYADVISOR_H
  10 #define LLVM_CODEGEN_REGALLOCPRIORITYADVISOR_H
  11
  12 #include "RegAllocEvictionAdvisor.h"
  13 #include "llvm/CodeGen/SlotIndexes.h"
  14 #include "llvm/Pass.h"
  15
  16 namespace llvm {
  17
  18 class MachineFunction;
  19 class VirtRegMap;
  20 class RAGreedy;
  21
  22 /// Interface to the priority advisor, which is responsible for prioritizing
  23 /// live ranges.
  24 class RegAllocPriorityAdvisor {
  25 public:
  26   RegAllocPriorityAdvisor(const RegAllocPriorityAdvisor &) = delete;
  27   RegAllocPriorityAdvisor(RegAllocPriorityAdvisor &&) = delete;
  28   virtual ~RegAllocPriorityAdvisor() = default;
  29
  30   /// Find the priority value for a live range. A float value is used since ML
  31   /// prefers it.
  32   virtual unsigned getPriority(const LiveInterval &LI) const = 0;
  33
  34   RegAllocPriorityAdvisor(const MachineFunction &MF, const RAGreedy &RA,
  35                           SlotIndexes *const Indexes);
  36
  37 protected:
  38   const RAGreedy &RA;
  39   LiveIntervals *const LIS;
  40   VirtRegMap *const VRM;
  41   MachineRegisterInfo *const MRI;
  42   const TargetRegisterInfo *const TRI;
  43   const RegisterClassInfo &RegClassInfo;
  44   SlotIndexes *const Indexes;
  45   const bool RegClassPriorityTrumpsGlobalness;
  46   const bool ReverseLocalAssignment;
  47 };
  48
  49 class DefaultPriorityAdvisor : public RegAllocPriorityAdvisor {
  50 public:
  51   DefaultPriorityAdvisor(const MachineFunction &MF, const RAGreedy &RA,
  52                          SlotIndexes *const Indexes)
  53       : RegAllocPriorityAdvisor(MF, RA, Indexes) {}
  54
  55 private:
  56   unsigned getPriority(const LiveInterval &LI) const override;
  57 };
  58
  59 class RegAllocPriorityAdvisorAnalysis : public ImmutablePass {
  60 public:
  61   enum class AdvisorMode : int { Default, Release, Development };
  62
  63   RegAllocPriorityAdvisorAnalysis(AdvisorMode Mode)
  64       : ImmutablePass(ID), Mode(Mode){};
  65   static char ID;
  66
  67   /// Get an advisor for the given context (i.e. machine function, etc)
  68   virtual std::unique_ptr<RegAllocPriorityAdvisor>
  69   getAdvisor(const MachineFunction &MF, const RAGreedy &RA) = 0;
  70   AdvisorMode getAdvisorMode() const { return Mode; }
  71   virtual void logRewardIfNeeded(const MachineFunction &MF,
  72                                  llvm::function_ref<float()> GetReward){};
  73
  74 protected:
  75   // This analysis preserves everything, and subclasses may have additional
  76   // requirements.
  77   void getAnalysisUsage(AnalysisUsage &AU) const override {
  78     AU.setPreservesAll();
  79   }
  80
  81 private:
  82   StringRef getPassName() const override;
  83   const AdvisorMode Mode;
  84 };
  85
  86 /// Specialization for the API used by the analysis infrastructure to create
  87 /// an instance of the priority advisor.
  88 template <> Pass *callDefaultCtor<RegAllocPriorityAdvisorAnalysis>();
  89
  90 RegAllocPriorityAdvisorAnalysis *createReleaseModePriorityAdvisor();
  91
  92 RegAllocPriorityAdvisorAnalysis *createDevelopmentModePriorityAdvisor();
  93
  94 } // namespace llvm
  95
  96 #endif // LLVM_CODEGEN_REGALLOCPRIORITYADVISOR_H