lib/CodeGen/LiveDebugVariables.h

   1 //===- LiveDebugVariables.h - Tracking debug info variables ----*- 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 //
  10 // This file provides the interface to the LiveDebugVariables analysis.
  11 //
  12 // The analysis removes DBG_VALUE instructions for virtual registers and tracks
  13 // live user variables in a data structure that can be updated during register
  14 // allocation.
  15 //
  16 // After register allocation new DBG_VALUE instructions are emitted to reflect
  17 // the new locations of user variables.
  18 //
  19 //===----------------------------------------------------------------------===//
  20
  21 #ifndef LLVM_CODEGEN_LIVEDEBUGVARIABLES_H
  22 #define LLVM_CODEGEN_LIVEDEBUGVARIABLES_H
  23
  24 #include "llvm/ADT/ArrayRef.h"
  25 #include "llvm/CodeGen/MachineFunctionPass.h"
  26
  27 namespace llvm {
  28
  29 class LiveInterval;
  30 class VirtRegMap;
  31
  32 class LiveDebugVariables : public MachineFunctionPass {
  33   void *pImpl;
  34 public:
  35   static char ID; // Pass identification, replacement for typeid
  36
  37   LiveDebugVariables();
  38   ~LiveDebugVariables();
  39
  40   /// renameRegister - Move any user variables in OldReg to NewReg:SubIdx.
  41   /// @param OldReg Old virtual register that is going away.
  42   /// @param NewReg New register holding the user variables.
  43   /// @param SubIdx If NewReg is a virtual register, SubIdx may indicate a sub-
  44   ///               register.
  45   void renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx);
  46
  47   /// splitRegister - Move any user variables in OldReg to the live ranges in
  48   /// NewRegs where they are live. Mark the values as unavailable where no new
  49   /// register is live.
  50   void splitRegister(unsigned OldReg, ArrayRef<LiveInterval*> NewRegs);
  51
  52   /// emitDebugValues - Emit new DBG_VALUE instructions reflecting the changes
  53   /// that happened during register allocation.
  54   /// @param VRM Rename virtual registers according to map.
  55   void emitDebugValues(VirtRegMap *VRM);
  56
  57   /// dump - Print data structures to dbgs().
  58   void dump();
  59
  60 private:
  61
  62   virtual bool runOnMachineFunction(MachineFunction &);
  63   virtual void releaseMemory();
  64   virtual void getAnalysisUsage(AnalysisUsage &) const;
  65
  66 };
  67
  68 } // namespace llvm
  69
  70 #endif // LLVM_CODEGEN_LIVEDEBUGVARIABLES_H