A representation of the largest SDNode, for use in sizeof().
Declared in <llvm/CodeGen/SelectionDAGNodes.h>
using LargestSDNode = AlignedCharArrayUnion<AtomicSDNode, TargetIndexSDNode, BlockAddressSDNode, GlobalAddressSDNode, PseudoProbeSDNode>;This needs to be a union because the largest node differs on 32 bit systems with 4 and 8 byte pointer alignment, respectively.