void llvm::calculateDbgValueHistory(const MachineFunction *MF, const TargetRegisterInfo *TRI, DbgValueHistoryMap &Result) { BitVector ChangingRegs(TRI->getNumRegs()); collectChangingRegs(MF, TRI, ChangingRegs); RegDescribedVarsMap RegVars; for (const auto &MBB : *MF) { for (const auto &MI : MBB) { if (!MI.isDebugValue()) { // Not a DBG_VALUE instruction. It may clobber registers which describe // some variables. applyToClobberedRegisters(MI, TRI, [&](unsigned RegNo) { if (ChangingRegs.test(RegNo)) clobberRegisterUses(RegVars, RegNo, Result, MI); }); continue; } assert(MI.getNumOperands() > 1 && "Invalid DBG_VALUE instruction!"); // Use the base variable (without any DW_OP_piece expressions) // as index into History. The full variables including the // piece expressions are attached to the MI. const DILocalVariable *RawVar = MI.getDebugVariable(); assert(RawVar->isValidLocationForIntrinsic(MI.getDebugLoc()) && "Expected inlined-at fields to agree"); InlinedVariable Var(RawVar, MI.getDebugLoc()->getInlinedAt()); if (unsigned PrevReg = Result.getRegisterForVar(Var)) dropRegDescribedVar(RegVars, PrevReg, Var); Result.startInstrRange(Var, MI); if (unsigned NewReg = isDescribedByReg(MI)) addRegDescribedVar(RegVars, NewReg, Var); } // Make sure locations for register-described variables are valid only // until the end of the basic block (unless it's the last basic block, in // which case let their liveness run off to the end of the function). if (!MBB.empty() && &MBB != &MF->back()) { for (auto I = RegVars.begin(), E = RegVars.end(); I != E;) { auto CurElem = I++; // CurElem can be erased below. if (ChangingRegs.test(CurElem->first)) clobberRegisterUses(RegVars, CurElem, Result, MBB.back()); } } } }
void llvm::calculateDbgValueHistory(const MachineFunction *MF, const TargetRegisterInfo *TRI, DbgValueHistoryMap &Result) { BitVector ChangingRegs(TRI->getNumRegs()); collectChangingRegs(MF, TRI, ChangingRegs); const TargetLowering *TLI = MF->getSubtarget().getTargetLowering(); unsigned SP = TLI->getStackPointerRegisterToSaveRestore(); RegDescribedVarsMap RegVars; for (const auto &MBB : *MF) { for (const auto &MI : MBB) { if (!MI.isDebugValue()) { // Not a DBG_VALUE instruction. It may clobber registers which describe // some variables. for (const MachineOperand &MO : MI.operands()) { if (MO.isReg() && MO.isDef() && MO.getReg()) { // If this is a virtual register, only clobber it since it doesn't // have aliases. if (TRI->isVirtualRegister(MO.getReg())) clobberRegisterUses(RegVars, MO.getReg(), Result, MI); // If this is a register def operand, it may end a debug value // range. else { for (MCRegAliasIterator AI(MO.getReg(), TRI, true); AI.isValid(); ++AI) if (ChangingRegs.test(*AI)) clobberRegisterUses(RegVars, *AI, Result, MI); } } else if (MO.isRegMask()) { // If this is a register mask operand, clobber all debug values in // non-CSRs. for (int I = ChangingRegs.find_first(); I != -1; I = ChangingRegs.find_next(I)) { // Don't consider SP to be clobbered by register masks. if (unsigned(I) != SP && TRI->isPhysicalRegister(I) && MO.clobbersPhysReg(I)) { clobberRegisterUses(RegVars, I, Result, MI); } } } } continue; } assert(MI.getNumOperands() > 1 && "Invalid DBG_VALUE instruction!"); // Use the base variable (without any DW_OP_piece expressions) // as index into History. The full variables including the // piece expressions are attached to the MI. const DILocalVariable *RawVar = MI.getDebugVariable(); assert(RawVar->isValidLocationForIntrinsic(MI.getDebugLoc()) && "Expected inlined-at fields to agree"); InlinedVariable Var(RawVar, MI.getDebugLoc()->getInlinedAt()); if (unsigned PrevReg = Result.getRegisterForVar(Var)) dropRegDescribedVar(RegVars, PrevReg, Var); Result.startInstrRange(Var, MI); if (unsigned NewReg = isDescribedByReg(MI)) addRegDescribedVar(RegVars, NewReg, Var); } // Make sure locations for register-described variables are valid only // until the end of the basic block (unless it's the last basic block, in // which case let their liveness run off to the end of the function). if (!MBB.empty() && &MBB != &MF->back()) { for (auto I = RegVars.begin(), E = RegVars.end(); I != E;) { auto CurElem = I++; // CurElem can be erased below. if (TRI->isVirtualRegister(CurElem->first) || ChangingRegs.test(CurElem->first)) clobberRegisterUses(RegVars, CurElem, Result, MBB.back()); } } } }