Currently it's one of the two opcodes that uses m_singletonValue, which is unnecessary. Our current plan is to remove m_singletonValue so that GenGC can have a simpler story for handling CodeBlocks/FunctionExecutables during nursery collections.
Created attachment 212507 [details]
Comment on attachment 212507 [details]
View in context: https://bugs.webkit.org/attachment.cgi?id=212507&action=review
Committed r156376: <http://trac.webkit.org/changeset/156376>