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 27namespace llvm { 28 29class LiveInterval; 30class VirtRegMap; 31 32class LiveDebugVariables : public MachineFunctionPass { 33 void *pImpl; 34public: 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 60private: 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