Don't cache the TargetLoweringInfo object inside of the FunctionLowering object.

The TargetLoweringInfo object is owned by the TargetMachine. In the future, the
TargetMachine object may change, which may also change the TargetLoweringInfo
object.

llvm-svn: 183356

llvm/include/llvm/CodeGen/FunctionLoweringInfo.h

@@ -49,8 +49,9 @@ class Value;
 /// function that is used when lowering a region of the function.
 ///
 class FunctionLoweringInfo {
+  const TargetMachine &TM;
+  const TargetLowering *TLI;
 public:
-  const TargetLowering &TLI;
   const Function *Fn;
   MachineFunction *MF;
   MachineRegisterInfo *RegInfo;
@@ -115,7 +116,7 @@ public:
   /// there's no other convenient place for it to live right now.
   std::vector<std::pair<MachineInstr*, unsigned> > PHINodesToUpdate;
 
-  explicit FunctionLoweringInfo(const TargetLowering &TLI);
+  explicit FunctionLoweringInfo(const TargetMachine &TM);
 
   /// set - Initialize this FunctionLoweringInfo with the given Function
   /// and its associated MachineFunction.

llvm/lib/CodeGen/SelectionDAG/FunctionLoweringInfo.cpp

@@ -55,21 +55,22 @@ static bool isUsedOutsideOfDefiningBlock(const Instruction *I) {
   return false;
 }
 
-FunctionLoweringInfo::FunctionLoweringInfo(const TargetLowering &tli)
+FunctionLoweringInfo::FunctionLoweringInfo(const TargetMachine &TM)
-  : TLI(tli) {
+  : TM(TM), TLI(0) {
 }
 
 void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf) {
   Fn = &fn;
   MF = &mf;
   RegInfo = &MF->getRegInfo();
+  TLI = TM.getTargetLowering();
 
   // Check whether the function can return without sret-demotion.
   SmallVector<ISD::OutputArg, 4> Outs;
-  GetReturnInfo(Fn->getReturnType(), Fn->getAttributes(), Outs, TLI);
+  GetReturnInfo(Fn->getReturnType(), Fn->getAttributes(), Outs, *TLI);
-  CanLowerReturn = TLI.CanLowerReturn(Fn->getCallingConv(), *MF,
+  CanLowerReturn = TLI->CanLowerReturn(Fn->getCallingConv(), *MF,
-                                      Fn->isVarArg(),
+                                       Fn->isVarArg(),
-                                      Outs, Fn->getContext());
+                                       Outs, Fn->getContext());
 
   // Initialize the mapping of values to registers.  This is only set up for
   // instruction values that are used outside of the block that defines
@@ -79,9 +80,9 @@ void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf) {
     if (const AllocaInst *AI = dyn_cast<AllocaInst>(I))
       if (const ConstantInt *CUI = dyn_cast<ConstantInt>(AI->getArraySize())) {
         Type *Ty = AI->getAllocatedType();
-        uint64_t TySize = TLI.getDataLayout()->getTypeAllocSize(Ty);
+        uint64_t TySize = TLI->getDataLayout()->getTypeAllocSize(Ty);
         unsigned Align =
-          std::max((unsigned)TLI.getDataLayout()->getPrefTypeAlignment(Ty),
+          std::max((unsigned)TLI->getDataLayout()->getPrefTypeAlignment(Ty),
                    AI->getAlignment());
 
         TySize *= CUI->getZExtValue();   // Get total allocated size.
@@ -167,10 +168,10 @@ void FunctionLoweringInfo::set(const Function &fn, MachineFunction &mf) {
       assert(PHIReg && "PHI node does not have an assigned virtual register!");
 
       SmallVector<EVT, 4> ValueVTs;
-      ComputeValueVTs(TLI, PN->getType(), ValueVTs);
+      ComputeValueVTs(*TLI, PN->getType(), ValueVTs);
       for (unsigned vti = 0, vte = ValueVTs.size(); vti != vte; ++vti) {
         EVT VT = ValueVTs[vti];
-        unsigned NumRegisters = TLI.getNumRegisters(Fn->getContext(), VT);
+        unsigned NumRegisters = TLI->getNumRegisters(Fn->getContext(), VT);
         const TargetInstrInfo *TII = MF->getTarget().getInstrInfo();
         for (unsigned i = 0; i != NumRegisters; ++i)
           BuildMI(MBB, DL, TII->get(TargetOpcode::PHI), PHIReg + i);
@@ -208,7 +209,7 @@ void FunctionLoweringInfo::clear() {
 
 /// CreateReg - Allocate a single virtual register for the given type.
 unsigned FunctionLoweringInfo::CreateReg(MVT VT) {
-  return RegInfo->createVirtualRegister(TLI.getRegClassFor(VT));
+  return RegInfo->createVirtualRegister(TLI->getRegClassFor(VT));
 }
 
 /// CreateRegs - Allocate the appropriate number of virtual registers of
@@ -220,14 +221,14 @@ unsigned FunctionLoweringInfo::CreateReg(MVT VT) {
 ///
 unsigned FunctionLoweringInfo::CreateRegs(Type *Ty) {
   SmallVector<EVT, 4> ValueVTs;
-  ComputeValueVTs(TLI, Ty, ValueVTs);
+  ComputeValueVTs(*TLI, Ty, ValueVTs);
 
   unsigned FirstReg = 0;
   for (unsigned Value = 0, e = ValueVTs.size(); Value != e; ++Value) {
     EVT ValueVT = ValueVTs[Value];
-    MVT RegisterVT = TLI.getRegisterType(Ty->getContext(), ValueVT);
+    MVT RegisterVT = TLI->getRegisterType(Ty->getContext(), ValueVT);
 
-    unsigned NumRegs = TLI.getNumRegisters(Ty->getContext(), ValueVT);
+    unsigned NumRegs = TLI->getNumRegisters(Ty->getContext(), ValueVT);
     for (unsigned i = 0; i != NumRegs; ++i) {
       unsigned R = CreateReg(RegisterVT);
       if (!FirstReg) FirstReg = R;
@@ -267,14 +268,14 @@ void FunctionLoweringInfo::ComputePHILiveOutRegInfo(const PHINode *PN) {
     return;
 
   SmallVector<EVT, 1> ValueVTs;
-  ComputeValueVTs(TLI, Ty, ValueVTs);
+  ComputeValueVTs(*TLI, Ty, ValueVTs);
   assert(ValueVTs.size() == 1 &&
          "PHIs with non-vector integer types should have a single VT.");
   EVT IntVT = ValueVTs[0];
 
-  if (TLI.getNumRegisters(PN->getContext(), IntVT) != 1)
+  if (TLI->getNumRegisters(PN->getContext(), IntVT) != 1)
     return;
-  IntVT = TLI.getTypeToTransformTo(PN->getContext(), IntVT);
+  IntVT = TLI->getTypeToTransformTo(PN->getContext(), IntVT);
   unsigned BitWidth = IntVT.getSizeInBits();
 
   unsigned DestReg = ValueMap[PN];

llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp

@@ -278,7 +278,7 @@ void TargetLowering::AdjustInstrPostInstrSelection(MachineInstr *MI,
 SelectionDAGISel::SelectionDAGISel(const TargetMachine &tm,
                                    CodeGenOpt::Level OL) :
   MachineFunctionPass(ID), TM(tm), TLI(*tm.getTargetLowering()),
-  FuncInfo(new FunctionLoweringInfo(TLI)),
+  FuncInfo(new FunctionLoweringInfo(TM)),
   CurDAG(new SelectionDAG(tm, OL)),
   SDB(new SelectionDAGBuilder(*CurDAG, *FuncInfo, OL)),
   GFI(),