extract.asm

一个汇编的开方子程序

	RSEG
_AX:	DSW	1
_AXH	EQU	(_AX+1)
_BX:	DSW	1
_BXH	EQU	(_BX+1)
_CX:	DSW	1
_CXH	EQU	(_CX+1)
_DX:	DSW	1
_DXH	EQU	(_DX+1)

	CSEG
PUBLIC	Extract
;input:		_ax;_cx
;function:	_ax,_cx平方和开方
Extract:PUSH	_AX
	PUSH	_BX
	PUSH	_CX
	PUSH	_DX
	ADD	18H,#10
	POP	_AX
	POP	_CX
	JBC     _AXH,7,EXT00
	NEG	_AX
EXT00:  JBC     _CXH,7,EXT01
        NEG     _CX
EXT01:  SUB     _BX,_AX,_CX
        JH      EXT05
        NEG     _BX
        SUB     _DX,_BX,_AX
        JH      EXT03
        NEG     _DX
        SHL     _DX,#1
        CMP     _DX,_AX
        JNH     EXT02
        MULU    _CX,#51218
        MULU    _AX,#41388
        ADD     _AX,_BX,_DX
	LJMP	ETEND
EXT02:  MULU    _CX,#57118
        MULU    _AX,#32538
        ADD     _AX,_BX,_DX
	LJMP	ETEND
EXT03:	SHR     _DX,#1
        CMP     _DX,_AX
        JH      EXT04
        MULU    _CX,#61968
        MULU    _AX,#22448
        ADD     _AX,_BX,_DX
	LJMP	ETEND
EXT04:  MULU    _CX,#65308
        MULU    _AX,#8308
        ADD     _AX,_BX,_DX
	LJMP	ETEND
EXT05:  SUB     _DX,_BX,_CX
        JH      EXT07
        NEG     _DX
        SHL     _DX,#1
        CMP     _DX,_CX
        JNH     EXT06
        MULU    _AX,#51218
        MULU    _CX,#41388
        ADD     _AX,_BX,_DX
	LJMP	ETEND
EXT06:  MULU    _AX,#57118
        MULU    _CX,#32538
        ADD     _AX,_BX,_DX
	LJMP	ETEND
EXT07:  SHR     _DX,#1
        CMP     _DX,_CX
        JH      EXT08
        MULU    _AX,#61968
        MULU    _CX,#22448
        ADD     _AX,_BX,_DX
	LJMP	ETEND
EXT08:  MULU    _AX,#65308
        MULU    _CX,#8308
        ADD     _AX,_BX,_DX
ETEND:	LD	1CH,_AX
	SUB	18H,#14
	POP	_DX
	POP	_CX
	POP	_BX
	POP	_AX
	RET
	END