4.3BSD - /usr/src/games/compat/compat.s

   1: .data 0
   2:         .asciz "	compat.s	4.1	82/05/12	"
   3: .text
   4:         .globl _regs
   5:         .globl _psl
   6:         .globl _pc
   7:         .globl _compat
   8: _compat:
   9:         .word 0x0000
  10: # fixup stack by doing rets from compat and the function
  11: # which called it but modifying frame pc's to stay here
  12:         moval l0,16(fp) # fix first return address
  13:         ret
  14: l0:     moval l1,16(fp) # fix first return address
  15:         ret
  16: l1:     moval l2,16(fp) # fix next return address
  17:         ret
  18: l2:     movl _psl,4(sp)
  19:         movl _pc,(sp)
  20: # copy back saved register values
  21:         movw _regs,r0
  22:         movw _regs+02,r1
  23:         movw _regs+04,r2
  24:         movw _regs+06,r3
  25:         movw _regs+010,r4
  26:         movw _regs+012,r5
  27:         movw _regs+014,r6
  28: # go to compatability mode with rei assuming correct psl is setup
  29:         rei
  30:         .globl _getregs
  31: _getregs:
  32:         .word 0
  33: # copy registers into known locations for examination or modification
  34:         movw r0,_regs
  35:         movw r1,_regs+02
  36:         movw r2,_regs+04
  37:         movw r3,_regs+06
  38:         movw r4,_regs+010
  39:         movw r5,_regs+012
  40:         movw r6,_regs+014
  41:         ret

Defined functions