The DFG JIT Construct implementation initially involved passing a this argument to the Construct node, and then the implementation of the Construct node would pass this argument. This was unnecessary, since Constructors create their own this argument. This was then half fixed: the Constructor node implementation stopped passing the this argument. But there is still a node generated for getting the this argument, and it is still a child of Construct. This leads to dead code, is confusing to reason about, and probably hurts performance.
Created attachment 108617 [details] the patch
Landed in r95927.