Make Buf.EXISTS-POS(1) 7x faster
Make Buf.EXISTS-POS(1) 7x faster

By letting rakudo take care of the unboxing itself, and not creating
a variable: this probably allows it to be inlined better, even though
the unboxing is now happening twice on the "in range" code path.

azawawi/rakudo,MasterDuke17/rakudo,tbrowder/rakudo,samcv/rakudo,tony-o/rakudo,raydiak/rakudo,Gnouc/rakudo,sjn/rakudo,samcv/rakudo,tony-o/rakudo,jonathanstowe/rakudo,sjn/rakudo,ab5tract/rakudo,tony-o/rakudo,labster/rakudo,usev6/rakudo,labster/rakudo,labster/rakudo,MasterDuke17/rakudo,jonathanstowe/rakudo,zostay/rakudo,tbrowder/rakudo,azawawi/rakudo,salortiz/rakudo,ab5tract/rakudo,rakudo/rakudo,ab5tract/rakudo,tbrowder/rakudo,softmoth/rakudo,b2gills/rakudo,nbrown/rakudo,salortiz/rakudo,sjn/rakudo,salortiz/rakudo,awwaiid/rakudo,MasterDuke17/rakudo,tony-o/rakudo,samcv/rakudo,Gnouc/rakudo,rakudo/rakudo,usev6/rakudo,awwaiid/rakudo,rakudo/rakudo,nbrown/rakudo,jonathanstowe/rakudo,sjn/rakudo,azawawi/rakudo,b2gills/rakudo,labster/rakudo,MasterDuke17/rakudo,rakudo/rakudo,MasterDuke17/rakudo,softmoth/rakudo,rakudo/rakudo,nbrown/rakudo,tbrowder/rakudo,jonathanstowe/rakudo,tony-o/rakudo,salortiz/rakudo,lucasbuchala/rakudo,samcv/rakudo,jonathanstowe/rakudo,salortiz/rakudo,usev6/rakudo,azawawi/rakudo,usev6/rakudo,ab5tract/rakudo,labster/rakudo,raydiak/rakudo,salortiz/rakudo,awwaiid/rakudo,softmoth/rakudo,Gnouc/rakudo,samcv/rakudo,zostay/rakudo,Gnouc/rakudo,tbrowder/rakudo,awwaiid/rakudo,lucasbuchala/rakudo,zostay/rakudo,sjn/rakudo,softmoth/rakudo,b2gills/rakudo,zostay/rakudo,labster/rakudo,ab5tract/rakudo,tbrowder/rakudo,b2gills/rakudo,nbrown/rakudo,lucasbuchala/rakudo,lucasbuchala/rakudo,b2gills/rakudo,lucasbuchala/rakudo,awwaiid/rakudo,MasterDuke17/rakudo,rakudo/rakudo,nbrown/rakudo,tony-o/rakudo,usev6/rakudo,Gnouc/rakudo,azawawi/rakudo,softmoth/rakudo,nbrown/rakudo,raydiak/rakudo,Gnouc/rakudo,raydiak/rakudo