comment "subroutine prologue"
.macro enter
st r13,@-sp
.endm
comment "subroutine epilogue"
.macro leave
ld r13,@sp+
jmp r13
.macro call subr
bl \subr
.macro several_nops
nop
comment "exit (0)"
.macro exit0
ldi r4, 1
ldi r0, 0
trap 15