Change all self assignments X=X to (void)X, so that we can turn on a

new gcc warning that complains on self-assignments and
self-initializations.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122458 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Transforms/Utils/AddrModeMatcher.h

@@ -90,7 +90,7 @@ public:
     bool Success = 
       AddressingModeMatcher(AddrModeInsts, TLI, AccessTy,
                             MemoryInst, Result).MatchAddr(V, 0);
-    Success = Success; assert(Success && "Couldn't select *anything*?");
+    (void)Success; assert(Success && "Couldn't select *anything*?");
     return Result;
   }
 private:

lib/Analysis/ConstantFolding.cpp

@@ -1216,7 +1216,7 @@ llvm::ConstantFoldCall(Function *F,
           Val.convert(APFloat::IEEEsingle, APFloat::rmNearestTiesToEven, &lost);
 
         // Conversion is always precise.
-        status = status;
+        (void)status;
         assert(status == APFloat::opOK && !lost &&
                "Precision lost during fp16 constfolding");
 
@@ -1313,4 +1313,3 @@ llvm::ConstantFoldCall(Function *F,
   }
   return 0;
 }
-

lib/Analysis/MemoryDependenceAnalysis.cpp

@@ -100,7 +100,7 @@ static void RemoveFromReverseMap(DenseMap<Instruction*,
   InstIt = ReverseMap.find(Inst);
   assert(InstIt != ReverseMap.end() && "Reverse map out of sync?");
   bool Found = InstIt->second.erase(Val);
-  assert(Found && "Invalid reverse map!"); Found=Found;
+  assert(Found && "Invalid reverse map!"); (void)Found;
   if (InstIt->second.empty())
     ReverseMap.erase(InstIt);
 }

lib/CodeGen/RegAllocLinearScan.cpp

@@ -934,7 +934,7 @@ LiveInterval *RALinScan::hasNextReloadInterval(LiveInterval *cur) {
 
 void RALinScan::DowngradeRegister(LiveInterval *li, unsigned Reg) {
   bool isNew = DowngradedRegs.insert(Reg);
-  isNew = isNew; // Silence compiler warning.
+  (void)isNew; // Silence compiler warning.
   assert(isNew && "Multiple reloads holding the same register?");
   DowngradeMap.insert(std::make_pair(li->reg, Reg));
   for (const unsigned *AS = tri_->getAliasSet(Reg); *AS; ++AS) {

lib/CodeGen/ScheduleDAGEmit.cpp

@@ -57,7 +57,7 @@ void ScheduleDAG::EmitPhysRegCopy(SUnit *SU,
       assert(I->getReg() && "Unknown physical register!");
       unsigned VRBase = MRI.createVirtualRegister(SU->CopyDstRC);
       bool isNew = VRBaseMap.insert(std::make_pair(SU, VRBase)).second;
-      isNew = isNew; // Silence compiler warning.
+      (void)isNew; // Silence compiler warning.
       assert(isNew && "Node emitted out of order - early");
       BuildMI(*BB, InsertPos, DebugLoc(), TII->get(TargetOpcode::COPY), VRBase)
         .addReg(I->getReg());

lib/CodeGen/SelectionDAG/InstrEmitter.cpp

@@ -67,7 +67,7 @@ EmitCopyFromReg(SDNode *Node, unsigned ResNo, bool IsClone, bool IsCloned,
     if (IsClone)
       VRBaseMap.erase(Op);
     bool isNew = VRBaseMap.insert(std::make_pair(Op, SrcReg)).second;
-    isNew = isNew; // Silence compiler warning.
+    (void)isNew; // Silence compiler warning.
     assert(isNew && "Node emitted out of order - early");
     return;
   }
@@ -150,7 +150,7 @@ EmitCopyFromReg(SDNode *Node, unsigned ResNo, bool IsClone, bool IsCloned,
   if (IsClone)
     VRBaseMap.erase(Op);
   bool isNew = VRBaseMap.insert(std::make_pair(Op, VRBase)).second;
-  isNew = isNew; // Silence compiler warning.
+  (void)isNew; // Silence compiler warning.
   assert(isNew && "Node emitted out of order - early");
 }
 
@@ -224,7 +224,7 @@ void InstrEmitter::CreateVirtualRegisters(SDNode *Node, MachineInstr *MI,
     if (IsClone)
       VRBaseMap.erase(Op);
     bool isNew = VRBaseMap.insert(std::make_pair(Op, VRBase)).second;
-    isNew = isNew; // Silence compiler warning.
+    (void)isNew; // Silence compiler warning.
     assert(isNew && "Node emitted out of order - early");
   }
 }
@@ -496,7 +496,7 @@ void InstrEmitter::EmitSubregNode(SDNode *Node,
      
   SDValue Op(Node, 0);
   bool isNew = VRBaseMap.insert(std::make_pair(Op, VRBase)).second;
-  isNew = isNew; // Silence compiler warning.
+  (void)isNew; // Silence compiler warning.
   assert(isNew && "Node emitted out of order - early");
 }
 
@@ -518,7 +518,7 @@ InstrEmitter::EmitCopyToRegClassNode(SDNode *Node,
 
   SDValue Op(Node, 0);
   bool isNew = VRBaseMap.insert(std::make_pair(Op, NewVReg)).second;
-  isNew = isNew; // Silence compiler warning.
+  (void)isNew; // Silence compiler warning.
   assert(isNew && "Node emitted out of order - early");
 }
 
@@ -555,7 +555,7 @@ void InstrEmitter::EmitRegSequence(SDNode *Node,
   MBB->insert(InsertPos, MI);
   SDValue Op(Node, 0);
   bool isNew = VRBaseMap.insert(std::make_pair(Op, NewVReg)).second;
-  isNew = isNew; // Silence compiler warning.
+  (void)isNew; // Silence compiler warning.
   assert(isNew && "Node emitted out of order - early");
 }
 

lib/CodeGen/StackSlotColoring.cpp

@@ -646,7 +646,7 @@ StackSlotColoring::UnfoldAndRewriteInstruction(MachineInstr *MI, int OldFI,
   } else {
     SmallVector<MachineInstr*, 4> NewMIs;
     bool Success = TII->unfoldMemoryOperand(MF, MI, Reg, false, false, NewMIs);
-    Success = Success; // Silence compiler warning.
+    (void)Success; // Silence compiler warning.
     assert(Success && "Failed to unfold!");
     MachineInstr *NewMI = NewMIs[0];
     MBB->insert(MI, NewMI);

lib/Support/PrettyStackTrace.cpp

@@ -107,7 +107,7 @@ static bool RegisterCrashPrinter() {
 PrettyStackTraceEntry::PrettyStackTraceEntry() {
   // The first time this is called, we register the crash printer.
   static bool HandlerRegistered = RegisterCrashPrinter();
-  HandlerRegistered = HandlerRegistered;
+  (void)HandlerRegistered;
     
   // Link ourselves.
   NextEntry = PrettyStackTraceHead.get();
@@ -131,4 +131,3 @@ void PrettyStackTraceProgram::print(raw_ostream &OS) const {
     OS << ArgV[i] << ' ';
   OS << '\n';
 }
-

lib/Support/StringMap.cpp

@@ -155,7 +155,7 @@ int StringMapImpl::FindKey(StringRef Key) const {
 void StringMapImpl::RemoveKey(StringMapEntryBase *V) {
   const char *VStr = (char*)V + ItemSize;
   StringMapEntryBase *V2 = RemoveKey(StringRef(VStr, V->getKeyLength()));
-  V2 = V2;
+  (void)V2;
   assert(V == V2 && "Didn't find key?");
 }
 

lib/Target/Mips/MipsISelDAGToDAG.cpp

@@ -325,7 +325,7 @@ SDNode* MipsDAGToDAGISel::Select(SDNode *Node) {
     case ISD::SUBE: 
     case ISD::ADDE: {
       SDValue InFlag = Node->getOperand(2), CmpLHS;
-      unsigned Opc = InFlag.getOpcode(); Opc=Opc;
+      unsigned Opc = InFlag.getOpcode(); (void)Opc;
       assert(((Opc == ISD::ADDC || Opc == ISD::ADDE) || 
               (Opc == ISD::SUBC || Opc == ISD::SUBE)) &&  
              "(ADD|SUB)E flag operand must come from (ADD|SUB)C/E insn");

lib/Target/PowerPC/PPCISelLowering.cpp

@@ -1058,7 +1058,6 @@ bool PPCTargetLowering::getPreIndexedAddressParts(SDNode *N, SDValue &Base,
     VT = LD->getMemoryVT();
 
   } else if (StoreSDNode *ST = dyn_cast<StoreSDNode>(N)) {
-    ST = ST;
     Ptr = ST->getBasePtr();
     VT  = ST->getMemoryVT();
   } else

lib/Transforms/Scalar/MemCpyOptimizer.cpp

@@ -504,7 +504,7 @@ bool MemCpyOpt::processStore(StoreInst *SI, BasicBlock::iterator &BBI) {
     DEBUG(dbgs() << "Replace stores:\n";
           for (unsigned i = 0, e = Range.TheStores.size(); i != e; ++i)
             dbgs() << *Range.TheStores[i] << '\n';
-          dbgs() << "With: " << *C << '\n'); C=C;
+          dbgs() << "With: " << *C << '\n'); (void)C;
   
     // Don't invalidate the iterator
     BBI = BI;
@@ -932,6 +932,3 @@ bool MemCpyOpt::runOnFunction(Function &F) {
   MD = 0;
   return MadeChange;
 }
-
-
-

lib/Transforms/Utils/AddrModeMatcher.cpp

@@ -568,7 +568,7 @@ IsProfitableToFoldIntoAddressingMode(Instruction *I, ExtAddrMode &AMBefore,
                                   MemoryInst, Result);
     Matcher.IgnoreProfitability = true;
     bool Success = Matcher.MatchAddr(Address, 0);
-    Success = Success; assert(Success && "Couldn't select *anything*?");
+    (void)Success; assert(Success && "Couldn't select *anything*?");
 
     // If the match didn't cover I, then it won't be shared by it.
     if (std::find(MatchedAddrModeInsts.begin(), MatchedAddrModeInsts.end(),

lib/Transforms/Utils/DemoteRegToStack.cpp

@@ -129,7 +129,7 @@ AllocaInst* llvm::DemotePHIToStack(PHINode *P, Instruction *AllocaPoint) {
   for (unsigned i = 0, e = P->getNumIncomingValues(); i < e; ++i) {
     if (InvokeInst *II = dyn_cast<InvokeInst>(P->getIncomingValue(i))) {
       assert(II->getParent() != P->getIncomingBlock(i) &&
-             "Invoke edge not supported yet"); II=II;
+             "Invoke edge not supported yet"); (void)II;
     }
     new StoreInst(P->getIncomingValue(i), Slot,
                   P->getIncomingBlock(i)->getTerminator());

lib/VMCore/Instructions.cpp

@@ -186,7 +186,7 @@ void CallInst::init(Value *Func, Value* const *Params, unsigned NumParams) {
 
   const FunctionType *FTy =
     cast<FunctionType>(cast<PointerType>(Func->getType())->getElementType());
-  FTy = FTy;  // silence warning.
+  (void)FTy;  // silence warning.
 
   assert((NumParams == FTy->getNumParams() ||
           (FTy->isVarArg() && NumParams > FTy->getNumParams())) &&
@@ -207,7 +207,7 @@ void CallInst::init(Value *Func, Value *Actual1, Value *Actual2) {
 
   const FunctionType *FTy =
     cast<FunctionType>(cast<PointerType>(Func->getType())->getElementType());
-  FTy = FTy;  // silence warning.
+  (void)FTy;  // silence warning.
 
   assert((FTy->getNumParams() == 2 ||
           (FTy->isVarArg() && FTy->getNumParams() < 2)) &&
@@ -227,7 +227,7 @@ void CallInst::init(Value *Func, Value *Actual) {
 
   const FunctionType *FTy =
     cast<FunctionType>(cast<PointerType>(Func->getType())->getElementType());
-  FTy = FTy;  // silence warning.
+  (void)FTy;  // silence warning.
 
   assert((FTy->getNumParams() == 1 ||
           (FTy->isVarArg() && FTy->getNumParams() == 0)) &&
@@ -243,7 +243,7 @@ void CallInst::init(Value *Func) {
 
   const FunctionType *FTy =
     cast<FunctionType>(cast<PointerType>(Func->getType())->getElementType());
-  FTy = FTy;  // silence warning.
+  (void)FTy;  // silence warning.
 
   assert(FTy->getNumParams() == 0 && "Calling a function with bad signature");
 }
@@ -500,7 +500,7 @@ void InvokeInst::init(Value *Fn, BasicBlock *IfNormal, BasicBlock *IfException,
   Op<-1>() = IfException;
   const FunctionType *FTy =
     cast<FunctionType>(cast<PointerType>(Fn->getType())->getElementType());
-  FTy = FTy;  // silence warning.
+  (void)FTy;  // silence warning.
 
   assert(((NumArgs == FTy->getNumParams()) ||
           (FTy->isVarArg() && NumArgs > FTy->getNumParams())) &&
@@ -1579,7 +1579,7 @@ BinaryOperator::BinaryOperator(BinaryOps iType, Value *S1, Value *S2,
 
 void BinaryOperator::init(BinaryOps iType) {
   Value *LHS = getOperand(0), *RHS = getOperand(1);
-  LHS = LHS; RHS = RHS; // Silence warnings.
+  (void)LHS; (void)RHS; // Silence warnings.
   assert(LHS->getType() == RHS->getType() &&
          "Binary operator operand types must match!");
 #ifndef NDEBUG

lib/VMCore/Type.cpp

@@ -1103,7 +1103,7 @@ void DerivedType::refineAbstractTypeTo(const Type *NewType) {
   while (!AbstractTypeUsers.empty() && NewTy != this) {
     AbstractTypeUser *User = AbstractTypeUsers.back();
 
-    unsigned OldSize = AbstractTypeUsers.size(); OldSize=OldSize;
+    unsigned OldSize = AbstractTypeUsers.size(); (void)OldSize;
 #ifdef DEBUG_MERGE_TYPES
     DEBUG(dbgs() << " REFINING user " << OldSize-1 << "[" << (void*)User
                  << "] of abstract type [" << (void*)this << " "
@@ -1130,7 +1130,7 @@ void DerivedType::notifyUsesThatTypeBecameConcrete() {
   DEBUG(dbgs() << "typeIsREFINED type: " << (void*)this << " " << *this <<"\n");
 #endif
 
-  unsigned OldSize = AbstractTypeUsers.size(); OldSize=OldSize;
+  unsigned OldSize = AbstractTypeUsers.size(); (void)OldSize;
   while (!AbstractTypeUsers.empty()) {
     AbstractTypeUser *ATU = AbstractTypeUsers.back();
     ATU->typeBecameConcrete(this);

lib/VMCore/TypesContext.h

@@ -317,7 +317,7 @@ public:
     // The old record is now out-of-date, because one of the children has been
     // updated.  Remove the obsolete entry from the map.
     unsigned NumErased = Map.erase(ValType::get(Ty));
-    assert(NumErased && "Element not found!"); NumErased = NumErased;
+    assert(NumErased && "Element not found!"); (void)NumErased;
 
     // Remember the structural hash for the type before we start hacking on it,
     // in case we need it later.

lib/VMCore/Value.cpp

@@ -255,7 +255,7 @@ void Value::takeName(Value *V) {
   // Get V's ST, this should always succed, because V has a name.
   ValueSymbolTable *VST;
   bool Failure = getSymTab(V, VST);
-  assert(!Failure && "V has a name, so it should have a ST!"); Failure=Failure;
+  assert(!Failure && "V has a name, so it should have a ST!"); (void)Failure;
 
   // If these values are both in the same symtab, we can do this very fast.
   // This works even if both values have no symtab yet.

unittests/Support/ValueHandleTest.cpp

@@ -108,7 +108,7 @@ TEST_F(ValueHandle, WeakVH_NullOnDeletion) {
 TEST_F(ValueHandle, AssertingVH_BasicOperation) {
   AssertingVH<CastInst> AVH(BitcastV.get());
   CastInst *implicit_to_exact_type = AVH;
-  implicit_to_exact_type = implicit_to_exact_type;  // Avoid warning.
+  (void)implicit_to_exact_type;  // Avoid warning.
 
   AssertingVH<Value> GenericAVH(BitcastV.get());
   EXPECT_EQ(BitcastV.get(), GenericAVH);
@@ -125,7 +125,7 @@ TEST_F(ValueHandle, AssertingVH_Const) {
   const CastInst *ConstBitcast = BitcastV.get();
   AssertingVH<const CastInst> AVH(ConstBitcast);
   const CastInst *implicit_to_exact_type = AVH;
-  implicit_to_exact_type = implicit_to_exact_type;  // Avoid warning.
+  (void)implicit_to_exact_type;  // Avoid warning.
 }
 
 TEST_F(ValueHandle, AssertingVH_Comparisons) {

utils/TableGen/CodeEmitterGen.cpp

@@ -264,7 +264,7 @@ void CodeEmitterGen::run(raw_ostream &o) {
   o << "  const unsigned opcode = MI.getOpcode();\n"
     << "  unsigned Value = InstBits[opcode];\n"
     << "  unsigned op = 0;\n"
-    << "  op = op;  // suppress warning\n"
+    << "  (void)op;  // suppress warning\n"
     << "  switch (opcode) {\n";
 
   // Emit each case statement