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|
;
; Borland assembler header
;
; Microsoft MASM subroutines for setting coprocessor precision
;
.286
.287
PREC_TEXT SEGMENT BYTE PUBLIC 'CODE'
PREC_TEXT ENDS
DGROUP group _DATA,_BSS
assume cs:PREC_TEXT,ds:DGROUP
_DATA segment word public 'DATA'
d@ label byte
d@w label word
_DATA ends
_BSS segment word public 'BSS'
b@ label byte
b@w label word
_BSS ends
; exception masks (1 = masked)
; 1 invalid operation
; 2 denormalized operand
; 4 zero divide
; 8 overflow
; 10 underflow
; 20 precision
_DATA SEGMENT
; double precision setting
;;ctlwrd dw 01230h ; note this traps on denormal operands!
;;ctld dw 0133fh ; this doesn't trap
ctld dw 01230h
; single precision
ctls dw 01030h
; long double precision
ctlld dw 01320h
_DATA ENDS
PREC_TEXT segment byte public 'CODE'
assume cs:PREC_TEXT,ds:DGROUP
; Set coprocessor to single precision float
PUBLIC _sprec
_sprec PROC FAR
fclex
fwait
finit
fwait
fldcw word ptr ctls
fwait
ret
_sprec ENDP
; set coprocessor to long double precision
PUBLIC _ldprec
_ldprec PROC far
fclex
fwait
finit
fwait
fldcw word ptr ctlld
fwait
ret
_ldprec ENDP
; set coprocessor to double precision
PUBLIC _dprec
_dprec PROC far
fclex
fwait
finit
fwait
fldcw word ptr ctld
fwait
ret
_dprec ENDP
; get a double promoted to long double size
; getld( &doub, &ldoub );
PUBLIC _getld
_getld PROC far
push bp
mov bp,sp
push bx
mov bx, word ptr [bp+4]
; fld st(0)
fld qword ptr [bx]
mov bx, word ptr [bp+6]
fstp tbyte ptr [bx]
mov bx, word ptr [bp+4]
fld qword ptr [bx]
mov bx, word ptr [bp+8]
fstp qword ptr [bx]
pop bx
pop bp
ret
_getld ENDP
PUBLIC _getprec
_getprec PROC far
push bp
mov bp,sp
sub sp,4
fstcw [bp-4]
fwait
mov ax,[bp-4]
add sp,4
pop bp
ret
_getprec ENDP
PUBLIC _fpclear
_fpclear PROC far
push bp
mov bp,sp
fnclex
fwait
pop bp
ret
_fpclear ENDP
PUBLIC _noexcept
_noexcept PROC far
push bp
mov bp,sp
push ax
sub sp,4
fnclex
fwait
fstcw [bp-4]
fwait
mov ax,[bp-4]
and ax,0FFC0h
or ax,003fh
mov [bp-4],ax
fldcw [bp-4]
add sp,4
pop ax
pop bp
ret
_noexcept ENDP
; single precision square root
; assumes coprocessor precision already set up
; return value in static __fac
PUBLIC _sqrtf
_sqrtf PROC FAR
push bp
mov bp,sp
fld DWORD PTR [bp+6]
fsqrt
fwait
mov sp,bp
pop bp
ret
_sqrtf ENDP
; double precision square root
; assumes coprocessor precision already set up
; return value in static __fac
PUBLIC _sqrt
_sqrt PROC FAR
push bp
mov bp,sp
fld QWORD PTR [bp+6]
fsqrt
fwait
mov sp,bp
pop bp
ret
_sqrt ENDP
; long double precision square root
; assumes coprocessor precision already set up
; return value in fp register
PUBLIC _sqrtl
_sqrtl PROC FAR
push bp
mov bp,sp
fld tbyte ptr [bp+6]
fsqrt
fwait
mov sp,bp
pop bp
ret
_sqrtl ENDP
PREC_TEXT ends
_DATA segment word public 'DATA'
s@ label byte
_DATA ends
PREC_TEXT segment byte public 'CODE'
PREC_TEXT ends
_s@ equ s@
public _sprec
public _dprec
public _ldprec
end
|
