1 .section ".text", #alloc, #execinstr 2 .align 8 3 .skip 16 4 .global _tas 5 ! .type _tas,2 6 _tas: 7 or %g0,1,%o1 8 swap [%o0],%o1 ! o0 points to lock; key is first word 9 retl 10 mov %o1, %o0 11 12 .size _tas,(.-_tas) 13