4.3BSD - /usr/src/new/icon/rt/setbound.s

   1: #include "../h/config.h"
   2: Global(_boundary)       /* Icon/C boundary */
   3: Global(_setbound)       /* Set the Icon/C boundary */
   4: Global(_clrbound)       /* Clear the Icon/C boundary */
   5: 
   6: #ifdef VAX
   7: /*
   8:  * setbound sets the boundary to the value of the fp of the
   9:  *  calling procedure.
  10:  */
  11: _setbound:
  12:         Mask    0x0             # Don't need to save any registers
  13:         tstl    _boundary       # If the boundary is already set
  14:         jneq    f1              #  just leave it alone
  15:         movl    12(fp),_boundary # Otherwise, set boundary to fp of
  16:                                 #  calling procedure.  Must use saved
  17:                                 #  fp because current fp points to
  18:                                 #  frame made upon entry to setbound.
  19: f1:     ret                     # Return
  20: /*
  21:  * clrbound clears the Icon/C boundary if returning to Icon
  22:  *  code from C code.
  23:  */
  24: _clrbound:
  25:         Mask    0x0             # Don't need to save any registers
  26:         cmpl    12(fp),_boundary # If the fp of the caller is equal
  27:                                 #  to the boundary, the return is
  28:                                 #  from C to Icon.
  29:         jneq    f11             # If that is the case,
  30:         clrl    _boundary       #  clear the boundary, otherwise,
  31: f11:    ret                     #  just return.
  32: #endif VAX
  33: 
  34: #ifdef PORT
  35: DummyFcn(_setbound)
  36: DummyFcn(_clrbound)
  37: #endif PORT
  38: 
  39: #ifdef PDP11
  40: DummyFcn(_setbound)
  41: DummyFcn(_clrbound)
  42: #endif PDP11

Defined functions