PPCReduceCRLogicals - fix static analyzer warnings. NFC

- Fix uninitialized variable warnings.
- Fix null dereference warnings.

Author: RKSimon

llvm/lib/Target/PowerPC/PPCReduceCRLogicals.cpp

@@ -375,10 +375,10 @@ class PPCReduceCRLogicals : public MachineFunctionPass {
   };
 
 private:
-  const PPCInstrInfo *TII;
-  MachineFunction *MF;
-  MachineRegisterInfo *MRI;
-  const MachineBranchProbabilityInfo *MBPI;
+  const PPCInstrInfo *TII = nullptr;
+  MachineFunction *MF = nullptr;
+  MachineRegisterInfo *MRI = nullptr;
+  const MachineBranchProbabilityInfo *MBPI = nullptr;
 
   // A vector to contain all the CR logical operations
   SmallVector<CRLogicalOpInfo, 16> AllCRLogicalOps;
@@ -470,21 +470,21 @@ PPCReduceCRLogicals::createCRLogicalOpInfo(MachineInstr &MIParam) {
   } else {
     MachineInstr *Def1 = lookThroughCRCopy(MIParam.getOperand(1).getReg(),
                                            Ret.SubregDef1, Ret.CopyDefs.first);
+    assert(Def1 && "Must be able to find a definition of operand 1.");
     Ret.DefsSingleUse &=
       MRI->hasOneNonDBGUse(Def1->getOperand(0).getReg());
     Ret.DefsSingleUse &=
       MRI->hasOneNonDBGUse(Ret.CopyDefs.first->getOperand(0).getReg());
-    assert(Def1 && "Must be able to find a definition of operand 1.");
     if (isBinary(MIParam)) {
       Ret.IsBinary = 1;
       MachineInstr *Def2 = lookThroughCRCopy(MIParam.getOperand(2).getReg(),
                                              Ret.SubregDef2,
                                              Ret.CopyDefs.second);
+      assert(Def2 && "Must be able to find a definition of operand 2.");
       Ret.DefsSingleUse &=
         MRI->hasOneNonDBGUse(Def2->getOperand(0).getReg());
       Ret.DefsSingleUse &=
         MRI->hasOneNonDBGUse(Ret.CopyDefs.second->getOperand(0).getReg());
-      assert(Def2 && "Must be able to find a definition of operand 2.");
       Ret.TrueDefs = std::make_pair(Def1, Def2);
     } else {
       Ret.TrueDefs = std::make_pair(Def1, nullptr);