Topspeed_JPI/TS/SRC/NOEMUL.A

(* Release 3.10 *)
(*-------------------------------------------------------------------------*
*                                                                          *
*  NOEMUL.A - hardware-only floating point support                         *
*                                                                          *
*  COPYRIGHT (C) 1989..1992 Clarion Software Corporation.                  *
*  All Rights Reserved                                                     *
*                                                                          *
*--------------------------------------------------------------------------*)

module noemul

NearCall = 1 - _fcall
SameDS   = 1 - _fdata
NearPtr  = 1 - _fptr
MThread  = _mthread
RegParam = _jpicall

segment EMU_TEXT  (EMU_CODE,28H)
segment _BSS(BSS,68H)

ExecFloatState: org 94

select EMU_TEXT

foption 2

ProcessFloat    = 14

public __FloatStoreSW :
    push bp
    mov  bp, sp
    sub  sp, 2
    fstsw [bp][-2]
    fwait
    mov  ax, [bp][-2]
    mov  sp, bp
    pop  bp
    ret  far 0

public __FloatStoreCW :
    push bp
    mov  bp, sp
    sub  sp, 2
    fstcw [bp][-2]
    fwait
    mov  ax, [bp][-2]
    mov  sp, bp
    pop  bp
    ret  far 0

public __FloatLoadCW :
    push bp
    mov  bp, sp
    sub  sp, 2
    mov  [bp][-2], ax
    fwait
    fldcw [bp][-2]
    mov  sp, bp
    pop  bp
    ret  far 0

public __FloatExecSave :

    push ax
    mov  ax, _BSS
    mov  es, ax
    fsave es:[ExecFloatState]
    pop  ax
    fwait
    ret  far 0

public __FloatExecRestore :

    push ax
    mov  ax, _BSS
    mov  es, ax
    frstor es:[ExecFloatState]
    pop  ax
    fwait
    ret  far 0

public __FloatSave :

    fsave es:[ProcessFloat]
    fwait
    ret  far 0

public __FloatRestore :

    frstor ds:[ProcessFloat]
    fwait
    ret  far 0

public __FloatFinish:
 ret far 0

public __FloatJmpSave :

st1_reg = 20
st2_reg = 30

    fld st(0), st(1)
    fstp  tbyte es:[di][st1_reg], st(0)
    fld st(0), st(2)
    fstp  tbyte es:[di][st2_reg], st(0)
    fwait
    ret  far 0

public __FloatJmpRestore :

    fld  tbyte st(0), ds:[si][st1_reg]
    fstp st(2), st(0)
    fld  tbyte st(0), ds:[si][st2_reg]
    fstp st(3), st(0)
    ret  far 0

extrn __math_excep

public __FloatMathExcepOs2 :
    (* always far called from coresig *)
    (*
       stack contains far return address to signal handler, then status word,
       then far return address to error location, the iret flags.
       This is how __math_excep likes it, so just jump there.
    *)
    fclex
    fwait
    jmp far __math_excep

public __FloatMathExcepDos :
  (*
     the stack contains a FAR return address to signal handler, then
     the far address of the point of exception, then the iret flags
  *)
  push ax              (* make room for status word *)
  push bp
  mov bp,sp
  push  ax
  mov   ax,[bp][4]     (* return ip *)
  mov   [bp][2],ax
  mov   ax,[bp][6]     (* return cs *)
  mov   [bp][4],ax
  fstsw [bp][6]        (* will bring in emulator ! *)
  pop   ax
  pop   bp
  fclex
  jmp far __math_excep

public __FloatInitInstance:
 push bp
 mov bp, sp
 push ax (* dummy *)
 finit
 fstcw [bp][-2]
 fwait
 or  word [bp][-2] , 0C00H (* round towards zero (chop) *)
 and word [bp][-2] ,~001DH (* enable invalid op/underflow/overflow/divide by zero exception *)
 fldcw [bp][-2]
 extrn __FloatInitStack
 call far __FloatInitStack
 mov sp,bp
 pop bp
 ret far 0

public __FloatInit:
 extrn __fp_1
 call far __fp_1
 call far __FloatInitInstance
 ret far 0


section

(*emuinit2*)
public  FIDRQQ   =  0
public  FIWRQQ   =  0

public  FIERQQ   =  0
public  FIARQQ   =  0
public  FISRQQ   =  0
public  FICRQQ   =  0


public  FJERQQ  =  0
public  FJARQQ  =  0
public  FJSRQQ  =  0
public  FJCRQQ  =  0

public  FIXRQQ  =  0 (* brings this module in - known to linker *)

segment EMU_STATE(DATA,68H)
select EMU_STATE
public  emuBuffer :
  org 0

end (*NUEMUL.A*)