[SelectionDAG] Add asserts to verify the vectorness of input and output types of TRUNCATE/ZERO_EXTEND/ANY_EXTEND/SIGN_EXTEND agree

[craig.topper]

Summary

As a result of the underlying cause of PR41678 we created an ANY_EXTEND node with a scalar result type and v1i1 input type. Ideally we would have asserted for this instead of letting it go through to instruction selection and generate bad machine IR

[spatel]

Could make a cast op helper for repeated asserts (including existing ones before this patch), but this LGTM - more asserts, less cryptic crashing.

[RKSimon]

LGTM

llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAG.cpp

case ISD::FP_EXTEND:
     assert(Operand.getValueType().bitsLT(VT) &&
            "Invalid fpext node, dst < src!");
     if (Operand.isUndef())
       return getUNDEF(VT);
     break;
   case ISD::SIGN_EXTEND:
     assert(VT.isInteger() && Operand.getValueType().isInteger() &&
            "Invalid SIGN_EXTEND!");
+    assert(VT.isVector() == Operand.getValueType().isVector() &&
+           "SIGN_EXTEND result type type should be vector iff the operand "
+           "type is vector!");
     if (Operand.getValueType() == VT) return Operand;   // noop extension
     assert((!VT.isVector() ||
             VT.getVectorNumElements() ==
             Operand.getValueType().getVectorNumElements()) &&
            "Vector element count mismatch!");
     assert(Operand.getValueType().bitsLT(VT) &&
            "Invalid sext node, dst < src!");
     if (OpOpcode == ISD::SIGN_EXTEND || OpOpcode == ISD::ZERO_EXTEND)
       return getNode(OpOpcode, DL, VT, Operand.getOperand(0));
     else if (OpOpcode == ISD::UNDEF)
       // sext(undef) = 0, because the top bits will all be the same.
       return getConstant(0, DL, VT);
     break;
   case ISD::ZERO_EXTEND:
     assert(VT.isInteger() && Operand.getValueType().isInteger() &&
            "Invalid ZERO_EXTEND!");
+    assert(VT.isVector() == Operand.getValueType().isVector() &&
+           "ZERO_EXTEND result type type should be vector iff the operand "
+           "type is vector!");
     if (Operand.getValueType() == VT) return Operand;   // noop extension
     assert((!VT.isVector() ||
             VT.getVectorNumElements() ==
             Operand.getValueType().getVectorNumElements()) &&
            "Vector element count mismatch!");
     assert(Operand.getValueType().bitsLT(VT) &&
            "Invalid zext node, dst < src!");
     if (OpOpcode == ISD::ZERO_EXTEND)   // (zext (zext x)) -> (zext x)
       return getNode(ISD::ZERO_EXTEND, DL, VT, Operand.getOperand(0));
     else if (OpOpcode == ISD::UNDEF)
       // zext(undef) = 0, because the top bits will be zero.
       return getConstant(0, DL, VT);
     break;
   case ISD::ANY_EXTEND:
     assert(VT.isInteger() && Operand.getValueType().isInteger() &&
            "Invalid ANY_EXTEND!");
+    assert(VT.isVector() == Operand.getValueType().isVector() &&
+           "ANY_EXTEND result type type should be vector iff the operand "
+           "type is vector!");
     if (Operand.getValueType() == VT) return Operand;   // noop extension
     assert((!VT.isVector() ||
             VT.getVectorNumElements() ==
             Operand.getValueType().getVectorNumElements()) &&
            "Vector element count mismatch!");
     assert(Operand.getValueType().bitsLT(VT) &&
            "Invalid anyext node, dst < src!");
 
if (OpOpcode == ISD::TRUNCATE) {
         transferDbgValues(Operand, OpOp);
         return OpOp;
       }
     }
     break;
   case ISD::TRUNCATE:
     assert(VT.isInteger() && Operand.getValueType().isInteger() &&
            "Invalid TRUNCATE!");
+    assert(VT.isVector() == Operand.getValueType().isVector() &&
+           "TRUNCATE result type type should be vector iff the operand "
+           "type is vector!");
     if (Operand.getValueType() == VT) return Operand;   // noop truncate
     assert((!VT.isVector() ||
             VT.getVectorNumElements() ==
             Operand.getValueType().getVectorNumElements()) &&
            "Vector element count mismatch!");
     assert(Operand.getValueType().bitsGT(VT) &&
            "Invalid truncate node, src < dst!");
     if (OpOpcode == ISD::TRUNCATE)