include/llvm/CodeGen/MachineBlockFrequencyInfo.h

   1 //====----- MachineBlockFrequencyInfo.h - MachineBlock Frequency Analysis ----====//
   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 //
  10 // Loops should be simplified before this analysis.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef LLVM_CODEGEN_MACHINEBLOCKFREQUENCY_H
  15 #define LLVM_CODEGEN_MACHINEBLOCKFREQUENCY_H
  16
  17 #include "llvm/CodeGen/MachineFunctionPass.h"
  18 #include <climits>
  19
  20 namespace llvm {
  21
  22 class MachineBranchProbabilityInfo;
  23 template<class BlockT, class FunctionT, class BranchProbInfoT>
  24 class BlockFrequencyImpl;
  25
  26 /// MachineBlockFrequencyInfo pass uses BlockFrequencyImpl implementation to estimate
  27 /// machine basic block frequencies.
  28 class MachineBlockFrequencyInfo : public MachineFunctionPass {
  29
  30   BlockFrequencyImpl<MachineBasicBlock, MachineFunction, MachineBranchProbabilityInfo> *MBFI;
  31
  32 public:
  33   static char ID;
  34
  35   MachineBlockFrequencyInfo();
  36
  37   ~MachineBlockFrequencyInfo();
  38
  39   void getAnalysisUsage(AnalysisUsage &AU) const;
  40
  41   bool runOnMachineFunction(MachineFunction &F);
  42
  43   /// getblockFreq - Return block frequency. Return 0 if we don't have the
  44   /// information. Please note that initial frequency is equal to 1024. It means
  45   /// that we should not rely on the value itself, but only on the comparison to
  46   /// the other block frequencies. We do this to avoid using of floating points.
  47   ///
  48   uint32_t getBlockFreq(MachineBasicBlock *MBB);
  49 };
  50
  51 }
  52
  53 #endif