Remove the SmallVector ctor that converts from a SmallVectorImpl.  This
conversion open the door for many nasty implicit conversion issues, and
can be easily solved by initializing with (V.begin(), V.end()) when 
needed.

This patch includes many small cleanups for sdisel also.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50340 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 507b2d7..dc335f8 100644
--- a/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -146,11 +146,11 @@
                  unsigned Reg, MVT::ValueType regvt, MVT::ValueType valuevt)
       : TLI(&tli), Regs(1, Reg), RegVTs(1, regvt), ValueVTs(1, valuevt) {}
     RegsForValue(const TargetLowering &tli,
-                 const SmallVectorImpl<unsigned> &regs, 
+                 const SmallVector<unsigned, 4> &regs, 
                  MVT::ValueType regvt, MVT::ValueType valuevt)
       : TLI(&tli), Regs(regs), RegVTs(1, regvt), ValueVTs(1, valuevt) {}
     RegsForValue(const TargetLowering &tli,
-                 const SmallVectorImpl<unsigned> &regs, 
+                 const SmallVector<unsigned, 4> &regs, 
                  const SmallVector<MVT::ValueType, 4> &regvts,
                  const SmallVector<MVT::ValueType, 4> &valuevts)
       : TLI(&tli), Regs(regs), RegVTs(regvts), ValueVTs(valuevts) {}
@@ -360,16 +360,15 @@
 /// the correctly promoted or expanded types.  Assign these registers
 /// consecutive vreg numbers and return the first assigned number.
 unsigned FunctionLoweringInfo::CreateRegForValue(const Value *V) {
-  const Type *Ty = V->getType();
   SmallVector<MVT::ValueType, 4> ValueVTs;
-  ComputeValueVTs(TLI, Ty, ValueVTs);
+  ComputeValueVTs(TLI, V->getType(), ValueVTs);
 
   unsigned FirstReg = 0;
   for (unsigned Value = 0; Value != ValueVTs.size(); ++Value) {
     MVT::ValueType ValueVT = ValueVTs[Value];
-    unsigned NumRegs = TLI.getNumRegisters(ValueVT);
     MVT::ValueType RegisterVT = TLI.getRegisterType(ValueVT);
 
+    unsigned NumRegs = TLI.getNumRegisters(ValueVT);
     for (unsigned i = 0; i != NumRegs; ++i) {
       unsigned R = MakeReg(RegisterVT);
       if (!FirstReg) FirstReg = R;
@@ -1042,18 +1041,22 @@
   if (N.Val) return N;
   
   const Type *VTy = V->getType();
-  MVT::ValueType VT = TLI.getValueType(VTy, true);
   if (Constant *C = const_cast<Constant*>(dyn_cast<Constant>(V))) {
-    if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
-      visit(CE->getOpcode(), *CE);
-      SDOperand N1 = NodeMap[V];
-      assert(N1.Val && "visit didn't populate the ValueMap!");
-      return N1;
-    } else if (GlobalValue *GV = dyn_cast<GlobalValue>(C)) {
+    MVT::ValueType VT = TLI.getValueType(VTy, true);
+    
+    if (ConstantInt *CI = dyn_cast<ConstantInt>(C))
+      return N = DAG.getConstant(CI->getValue(), VT);
+
+    if (GlobalValue *GV = dyn_cast<GlobalValue>(C))
       return N = DAG.getGlobalAddress(GV, VT);
-    } else if (isa<ConstantPointerNull>(C)) {
+    
+    if (isa<ConstantPointerNull>(C))
       return N = DAG.getConstant(0, TLI.getPointerTy());
-    } else if (isa<UndefValue>(C)) {
+    
+    if (ConstantFP *CFP = dyn_cast<ConstantFP>(C))
+      return N = DAG.getConstantFP(CFP->getValueAPF(), VT);
+    
+    if (isa<UndefValue>(C)) {
       if (!isa<VectorType>(VTy))
         return N = DAG.getNode(ISD::UNDEF, VT);
 
@@ -1067,44 +1070,46 @@
       
       // Create a VConstant node with generic Vector type.
       MVT::ValueType VT = MVT::getVectorType(PVT, NumElements);
-      return N = DAG.getNode(ISD::BUILD_VECTOR, VT,
-                             &Ops[0], Ops.size());
-    } else if (ConstantFP *CFP = dyn_cast<ConstantFP>(C)) {
-      return N = DAG.getConstantFP(CFP->getValueAPF(), VT);
-    } else if (const VectorType *PTy = dyn_cast<VectorType>(VTy)) {
-      unsigned NumElements = PTy->getNumElements();
-      MVT::ValueType PVT = TLI.getValueType(PTy->getElementType());
-      
-      // Now that we know the number and type of the elements, push a
-      // Constant or ConstantFP node onto the ops list for each element of
-      // the vector constant.
-      SmallVector<SDOperand, 8> Ops;
-      if (ConstantVector *CP = dyn_cast<ConstantVector>(C)) {
-        for (unsigned i = 0; i != NumElements; ++i)
-          Ops.push_back(getValue(CP->getOperand(i)));
-      } else {
-        assert(isa<ConstantAggregateZero>(C) && "Unknown vector constant!");
-        SDOperand Op;
-        if (MVT::isFloatingPoint(PVT))
-          Op = DAG.getConstantFP(0, PVT);
-        else
-          Op = DAG.getConstant(0, PVT);
-        Ops.assign(NumElements, Op);
-      }
-      
-      // Create a BUILD_VECTOR node.
-      MVT::ValueType VT = MVT::getVectorType(PVT, NumElements);
-      return NodeMap[V] = DAG.getNode(ISD::BUILD_VECTOR, VT, &Ops[0],
-                                      Ops.size());
-    } else {
-      // Canonicalize all constant ints to be unsigned.
-      return N = DAG.getConstant(cast<ConstantInt>(C)->getValue(),VT);
+      return N = DAG.getNode(ISD::BUILD_VECTOR, VT, &Ops[0], Ops.size());
     }
+
+    if (ConstantExpr *CE = dyn_cast<ConstantExpr>(C)) {
+      visit(CE->getOpcode(), *CE);
+      SDOperand N1 = NodeMap[V];
+      assert(N1.Val && "visit didn't populate the ValueMap!");
+      return N1;
+    }
+    
+    const VectorType *VecTy = cast<VectorType>(VTy);
+    unsigned NumElements = VecTy->getNumElements();
+    MVT::ValueType PVT = TLI.getValueType(VecTy->getElementType());
+    
+    // Now that we know the number and type of the elements, push a
+    // Constant or ConstantFP node onto the ops list for each element of
+    // the vector constant.
+    SmallVector<SDOperand, 8> Ops;
+    if (ConstantVector *CP = dyn_cast<ConstantVector>(C)) {
+      for (unsigned i = 0; i != NumElements; ++i)
+        Ops.push_back(getValue(CP->getOperand(i)));
+    } else {
+      assert(isa<ConstantAggregateZero>(C) && "Unknown vector constant!");
+      SDOperand Op;
+      if (MVT::isFloatingPoint(PVT))
+        Op = DAG.getConstantFP(0, PVT);
+      else
+        Op = DAG.getConstant(0, PVT);
+      Ops.assign(NumElements, Op);
+    }
+    
+    // Create a BUILD_VECTOR node.
+    return NodeMap[V] = DAG.getNode(ISD::BUILD_VECTOR, VT, &Ops[0], Ops.size());
   }
       
+  // If this is a static alloca, generate it as the frameindex instead of
+  // computation.
   if (const AllocaInst *AI = dyn_cast<AllocaInst>(V)) {
     std::map<const AllocaInst*, int>::iterator SI =
-    FuncInfo.StaticAllocaMap.find(AI);
+      FuncInfo.StaticAllocaMap.find(AI);
     if (SI != FuncInfo.StaticAllocaMap.end())
       return DAG.getFrameIndex(SI->second, TLI.getPointerTy());
   }
@@ -1114,7 +1119,6 @@
   
   RegsForValue RFV(TLI, InReg, VTy);
   SDOperand Chain = DAG.getEntryNode();
-
   return RFV.getCopyFromRegs(DAG, Chain, NULL);
 }
 
@@ -1124,6 +1128,7 @@
     DAG.setRoot(DAG.getNode(ISD::RET, MVT::Other, getControlRoot()));
     return;
   }
+  
   SmallVector<SDOperand, 8> NewValues;
   NewValues.push_back(getControlRoot());
   for (unsigned i = 0, e = I.getNumOperands(); i != e; ++i) {  
@@ -3600,7 +3605,7 @@
   
   
   MachineFunction &MF = DAG.getMachineFunction();
-  SmallVector<unsigned, 8> Regs;
+  SmallVector<unsigned, 4> Regs;
   
   // If this is a constraint for a single physreg, or a constraint for a
   // register class, find it.