UNIX 6th Ed. - /usr/source/tmg/tmgb/arith.s

   1: .globl succ,fail,iget
   2: .globl seekchar,getword,alterword
   3: .globl sprv,update
   4: .globl .l,.u,.p,.t,.st,
   5: 
   6: / infix =
   7: .st:
   8:         jsr     pc,sprv
   9:         mov     (sp)+,(sp)
  10:         mov     (sp)+,(sp)
  11: / update
  12: .u:
  13:         jsr     pc,update
  14:         br      9f
  15: / pop stack
  16: .p:
  17:         jsr     pc,sprv
  18:         cmp     (sp)+,(sp)+
  19:         br      9f
  20: / test stack
  21: .t:
  22:         jsr     pc,sprv
  23:         mov     (sp)+,(sp)+
  24:         bne     9f
  25:         jmp     fail
  26: / load named value
  27: / rvalue into (sp), lvalue into 2(sp)
  28: .l:
  29:         jsr     pc,iget
  30:         mov     r0,-(sp)
  31:         mov     (r0),-(sp)
  32:         br      9f
  33: / update a stored value, used by all assignments
  34: update:
  35:         cmp     2+2(sp),$-1
  36:         beq     1f
  37:         mov     0+2(sp),*2+2(sp)
  38:         rts     pc
  39: 1:
  40:         mov     4+2(sp),r1
  41:         mov     6+2(sp),r0
  42:         jsr     pc,seekchar
  43:         mov     0+2(sp),r0
  44:         jsr     pc,alterword
  45: / make sp hold a simple rv (forget it might be a table value)
  46: sprv:
  47:         mov     (sp)+,r0
  48:         cmp     $-1,2(sp)
  49:         bne     1f
  50:         mov     (sp)+,(sp)
  51:         mov     (sp)+,(sp)
  52: 1:
  53:         mov     r0,pc
  54: 9:
  55:         jmp     succ

Defined functions