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 71