Improve GMS performance by doing quick and cheap checks first during C stack scan.
Improve GMS performance by doing quick and cheap checks first during C stack scan.

parrot/parrot,FROGGS/parrot,youprofit/parrot,FROGGS/parrot,tkob/parrot,gagern/parrot,gitster/parrot,gitster/parrot,parrot/parrot,FROGGS/parrot,youprofit/parrot,gitster/parrot,youprofit/parrot,FROGGS/parrot,FROGGS/parrot,tkob/parrot,parrot/parrot,gagern/parrot,gagern/parrot,parrot/parrot,FROGGS/parrot,youprofit/parrot,gitster/parrot,tkob/parrot,tkob/parrot,gitster/parrot,tkob/parrot,gitster/parrot,gagern/parrot,tkob/parrot,youprofit/parrot,tkob/parrot,FROGGS/parrot,youprofit/parrot,FROGGS/parrot,gitster/parrot,tkob/parrot,gagern/parrot,parrot/parrot,youprofit/parrot,youprofit/parrot,gagern/parrot,gagern/parrot