1
0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2024-10-31 07:52:55 +01:00
llvm-mirror/lib/CodeGen/LiveDebugVariables.h
Jakob Stoklund Olesen 6e6ed39f02 Update LiveDebugVariables after live range splitting.
After a virtual register is split, update any debug user variables that resided
in the old register. This ensures that the LiveDebugVariables are still correct
after register allocation.

This may create DBG_VALUE instructions that place a user variable in a register
in parts of the function and in a stack slot in other parts. DwarfDebug
currently doesn't support that.

llvm-svn: 130998
2011-05-06 18:00:02 +00:00

71 lines
2.3 KiB
C++

//===- LiveDebugVariables.h - Tracking debug info variables ----*- c++ -*--===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file provides the interface to the LiveDebugVariables analysis.
//
// The analysis removes DBG_VALUE instructions for virtual registers and tracks
// live user variables in a data structure that can be updated during register
// allocation.
//
// After register allocation new DBG_VALUE instructions are emitted to reflect
// the new locations of user variables.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_CODEGEN_LIVEDEBUGVARIABLES_H
#define LLVM_CODEGEN_LIVEDEBUGVARIABLES_H
#include "llvm/ADT/ArrayRef.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
namespace llvm {
class LiveInterval;
class VirtRegMap;
class LiveDebugVariables : public MachineFunctionPass {
void *pImpl;
public:
static char ID; // Pass identification, replacement for typeid
LiveDebugVariables();
~LiveDebugVariables();
/// renameRegister - Move any user variables in OldReg to NewReg:SubIdx.
/// @param OldReg Old virtual register that is going away.
/// @param NewReg New register holding the user variables.
/// @param SubIdx If NewReg is a virtual register, SubIdx may indicate a sub-
/// register.
void renameRegister(unsigned OldReg, unsigned NewReg, unsigned SubIdx);
/// splitRegister - Move any user variables in OldReg to the live ranges in
/// NewRegs where they are live. Mark the values as unavailable where no new
/// register is live.
void splitRegister(unsigned OldReg, ArrayRef<LiveInterval*> NewRegs);
/// emitDebugValues - Emit new DBG_VALUE instructions reflecting the changes
/// that happened during register allocation.
/// @param VRM Rename virtual registers according to map.
void emitDebugValues(VirtRegMap *VRM);
/// dump - Print data structures to dbgs().
void dump();
private:
virtual bool runOnMachineFunction(MachineFunction &);
virtual void releaseMemory();
virtual void getAnalysisUsage(AnalysisUsage &) const;
};
} // namespace llvm
#endif // LLVM_CODEGEN_LIVEDEBUGVARIABLES_H