fix PPC JIT `vector-length'  Merge to 5.0.2
fix PPC JIT `vector-length'
 Merge to 5.0.2

mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket,mafagafogigante/racket