Category : C Source Code
Archive   : CEPHES22.ZIP
Filename : SUBM.ASM

; Static Name Aliases
;
TITLE subm

include qhead.asm

;_TEXT SEGMENT BYTE PUBLIC 'CODE'
;_TEXT ENDS
;CONST SEGMENT WORD PUBLIC 'CONST'
;CONST ENDS
;_BSS SEGMENT WORD PUBLIC 'BSS'
;_BSS ENDS
;_DATA SEGMENT WORD PUBLIC 'DATA'
;_DATA ENDS
;DGROUP GROUP CONST, _BSS, _DATA
; ASSUME CS: _TEXT, DS: DGROUP, SS: DGROUP, ES: DGROUP

PUBLIC _subm, _addm, _shdn1, _shup1, _shdn8, _shup8, _shdn16, _shup16

;_DATA SEGMENT
;EXTRN __chkstk:NEAR
;_DATA ENDS

_TEXT SEGMENT

; number of 16 bit words in mantissa area:
;OMG = 10
; offset to last word of mantissa area = 2*OMG+2:
;OFFS = 22

; Subtract mantissa of x from mantissa of y, result to y
; subm( x, y )
PUBLIC _subm
_subm PROC NEAR
push bp
mov bp,sp
push si

mov si,WORD PTR [bp+4]
mov bx,WORD PTR [bp+6]
clc

i=NQ+NQ
REPT OMG+1
mov dx,i[bx]
sbb dx,i[si]
mov i[bx],dx
i=i-2
ENDM
pop si
pop bp
ret
_subm ENDP



; add mantissa of x to mantissa of y, result to y
; addm( x, y );
PUBLIC _addm
_addm PROC NEAR
push bp
mov bp,sp
push si

mov si,[bp+4]
mov bx,[bp+6]
clc

i=NQ+NQ
REPT OMG+1
mov dx,i[bx]
adc dx,i[si]
mov i[bx],dx
i=i-2
ENDM
pop si
pop bp
ret
_addm ENDP


; shift mantissa of x down 1 bit
; shdn1(x);
PUBLIC _shdn1
_shdn1 PROC NEAR
push bp
mov bp,sp

mov bx,[bp+4]
clc

i=4
REPT OMG+1
rcr WORD PTR i[bx],1
i=i+2
ENDM
pop bp
ret
_shdn1 ENDP



; shift mantissa of x up 1 bit
; shup1(x);
PUBLIC _shup1
_shup1 PROC NEAR
push bp
mov bp,sp

mov bx,[bp+4]
clc

i=NQ+NQ
REPT OMG+1
rcl WORD PTR i[bx],1
i=i-2
ENDM
pop bp
ret
_shup1 ENDP



; shift mantissa of x down 8 bits
; shdn8(x);
PUBLIC _shdn8
_shdn8 PROC NEAR
push bp
mov bp,sp

mov bx,[bp+4]
sub dx,dx
i=4
REPT OMG+1
mov ax,WORD PTR i[bx]
xchg al,ah
xchg ah,dl
mov WORD PTR i[bx],ax
i=i+2
ENDM
pop bp
ret
_shdn8 ENDP



; shift mantissa of x up 8 bits
; shup8(x);
PUBLIC _shup8
_shup8 PROC NEAR
push bp
mov bp,sp

mov bx,[bp+4]
sub dx,dx
i=NQ+NQ
REPT OMG+1
mov ax,WORD PTR i[bx]
xchg al,ah
xchg al,dl
mov WORD PTR i[bx],ax
i=i-2
ENDM
pop bp
ret
_shup8 ENDP



; shift mantissa of x down 16 bits
; shdn16(x);
PUBLIC _shdn16
_shdn16 PROC NEAR
push bp
mov bp,sp

mov bx,[bp+4]
sub dx,dx
i=4
REPT OMG+1
mov ax,WORD PTR i[bx]
xchg ax,dx
mov WORD PTR i[bx],ax
i=i+2
ENDM
pop bp
ret
_shdn16 ENDP


; shift mantissa of x up 16 bits
; shup16(x);
PUBLIC _shup16
_shup16 PROC NEAR
push bp
mov bp,sp

mov bx,[bp+4]
sub dx,dx
i=NQ+NQ
REPT OMG+1
mov ax,WORD PTR i[bx]
xchg ax,dx
mov WORD PTR i[bx],ax
i=i-2
ENDM
pop bp
ret
_shup16 ENDP




; qmov(a,b)
; copy q type number from a to b

PUBLIC _qmov
_qmov PROC NEAR
push bp
mov bp,sp
push si
push di
push cx

mov si, word ptr [bp]+4
mov di, word ptr [bp]+6
mov cx, NQ
rep movsw

pop cx
pop di
pop si
pop bp
ret
_qmov ENDP




; qmovz(a,b)
; copy q type number from a to b
; and clear the bottom guard word of b

PUBLIC _qmovz
_qmovz PROC NEAR
push bp
mov bp,sp
push si
push di
push cx

mov si, word ptr [bp]+4
mov di, word ptr [bp]+6
mov cx, NQ
rep movsw

mov word ptr [di],0

pop cx
pop di
pop si
pop bp
ret
_qmovz ENDP

_TEXT ENDS
END