525 lines
14 KiB
NASM
525 lines
14 KiB
NASM
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;
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; Copyright (c) Mix Software 1988
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;
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; ---------------------------------------
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; LONG ABSOLUTE VALUE
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; ---------------------------------------
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;
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IDT LABS
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DEF LABS
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DEF labs
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labs equ $
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LABS MOV BX,SP
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MOV AX,[BX][%PARM1-2] ; GET L1
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MOV DX,[BX][%PARM2-2] ; GET H1
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TEST DX,DX
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JNS POS
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NEG DX
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NEG AX
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SBB DX,%0
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POS RETSEG
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END
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;
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;----------------------------------------------------
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; LONG MULTIPLY
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;----------------------------------------------------
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IDT $_LMUL
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DEF $_LMUL
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$_LMUL PUSH BP
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MOV BP,SP
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MOV AX,[BP][%PARM1] ; LSW OF MULTIPLIER
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MOV BX,[BP][%PARM2] ; MSW OF MULTIPLIER
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MOV CX,[BP][%PARM3] ; LSW OF MULTIPLICAND
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MOV DX,[BP][%PARM4] ; MSW OF MULTIPLICAND
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PUSH BX
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XOR BX,DX ; SIGN OF RESULT
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ROL BX ; SAVE IN CARRY
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POP BX
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PUSHF
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TEST BX,BX ; CHECK SIGN
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JNS MUL01
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NEG BX
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NEG AX
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SBB BX,%0
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MUL01 TEST DX,DX ; CHECK SIGN
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JNS MUL02
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NEG DX
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NEG CX
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SBB DX,%0
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MUL02 PUSH DX
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PUSH AX
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MUL CX ; LSW*LSW
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MOV SI,AX ; SAVE LSW OF RESULT
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MOV DI,DX ; MSW PARTIAL
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POP AX
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POP DX
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MUL DX ; L1*H1
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ADD DI,AX
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MOV AX,BX
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MUL CX ; L2*H1
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ADD AX,DI
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MOV DX,SI
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POPF
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JNB MUL03 ; NOT NEGATIVE
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NEG AX
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NEG DX
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SBB AX,0
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MUL03 XCHG AX,DX
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POP BP
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RETSEG
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END
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;
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;----------------------------------------------------
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; unsigned long multiply
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;----------------------------------------------------
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IDT $_LUMUL
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DEF $_LUMUL
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$_LUMUL PUSH BP
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MOV BP,SP
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MOV AX,[BP][%PARM1] ; LSW OF MULTIPLIER
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MOV BX,[BP][%PARM2] ; MSW OF MULTIPLIER
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MOV CX,[BP][%PARM3] ; LSW OF MULTIPLICAND
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MOV DX,[BP][%PARM4] ; MSW OF MULTIPLICAND
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PUSH DX
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PUSH AX
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MUL CX ; LSW*LSW
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MOV SI,AX ; SAVE LSW OF RESULT
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MOV DI,DX ; MSW PARTIAL
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POP AX
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POP DX
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MUL DX ; L1*H1
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ADD DI,AX
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MOV AX,BX
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MUL CX ; L2*H1
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ADD AX,DI
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MOV DX,SI
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XCHG AX,DX
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POP BP
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RETSEG
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END
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;
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;-----------------------------------------
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; DIVIDE LONG
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;-----------------------------------------
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;
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;
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DIVBY0 EQU >85
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IDT $_LDIV
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DEF $_LDIV
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DREF $$ARTERM
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DREF errno
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FREF $_FATAL
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$_LDIV PUSH BP
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MOV BP,SP
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MOV BX,[BP][%PARM1] ;BX=LSW OF DIVISOR
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MOV AX,[BP][%PARM2] ;AX=MSW OF DIVISOR
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MOV DX,[BP][%PARM3] ;DX=LSW OF DIVIDEND
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MOV CX,[BP][%PARM4] ;CX=MSW OF DIVIDEND
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CALL DIVIDE
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MOV DX,BX
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XCHG AX,DX
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POP BP
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RETSEG
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;
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;-----------------------------------------
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; MOD LONG
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;-----------------------------------------
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;
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;
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DEF $_LMOD
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DEF $_LBENCO
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$_LBENCO EQU $
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$_LMOD PUSH BP
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MOV BP,SP
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MOV BX,[BP][%PARM1] ;BX=LSW OF DIVISOR
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MOV AX,[BP][%PARM2] ;AX=MSW OF DIVISOR
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MOV DX,[BP][%PARM3] ;DX=LSW OF DIVIDEND
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MOV CX,[BP][%PARM4] ;CX=MSW OF DIVIDEND
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CALL DIVIDE
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MOV AX,CX
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XCHG AX,DX
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POP BP
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RETSEG
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;
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DEF $_LUDIV
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$_LUDIV PUSH BP
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MOV BP,SP
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MOV BX,[BP][%PARM1] ;BX=LSW OF DIVISOR
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MOV AX,[BP][%PARM2] ;AX=MSW OF DIVISOR
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MOV DX,[BP][%PARM3] ;DX=LSW OF DIVIDEND
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MOV CX,[BP][%PARM4] ;CX=MSW OF DIVIDEND
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CALL UDIVIDE
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MOV DX,BX
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XCHG AX,DX
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POP BP
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RETSEG
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;
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;-----------------------------------------
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; MOD LONG
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;-----------------------------------------
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;
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;
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DEF $_LUMOD
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$_LUMOD PUSH BP
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MOV BP,SP
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MOV BX,[BP][%PARM1] ;BX=LSW OF DIVISOR
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MOV AX,[BP][%PARM2] ;AX=MSW OF DIVISOR
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MOV DX,[BP][%PARM3] ;DX=LSW OF DIVIDEND
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MOV CX,[BP][%PARM4] ;CX=MSW OF DIVIDEND
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CALL UDIVIDE
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MOV AX,CX
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XCHG AX,DX
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POP BP
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RETSEG
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;
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; ---------------------------------------
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; ldiv - divide and return both
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; quotient and reamainder
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; ---------------------------------------
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; typedef struct {
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; long quot; /* quotient */
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; long rem; /* remainder */
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; } ldiv_t;
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;
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; ldiv_t div(long numer, long denom)
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; {
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; ldiv_t s;
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; s.quot = numer/denom;
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; s.rem = numer%denom;
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; return s;
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; }
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;
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IDT ldiv
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DEF ldiv
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NUMER EQU PARM1+4
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DENOM EQU PARM3+4
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STRUC EQU PARM1+2
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;
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ldiv PUSH BP
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MOV BP,SP
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MOV BX,[BP][%DENOM] ;BX=LSW OF DIVISOR
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MOV AX,[BP][%DENOM+2] ;AX=MSW OF DIVISOR
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MOV DX,[BP][%NUMER] ;DX=LSW OF DIVIDEND
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MOV CX,[BP][%NUMER+2] ;CX=MSW OF DIVIDEND
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CALL DIVIDE
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MOV SI,[BP][%STRUC]
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MOV [SI],BX
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MOV [SI][%2],AX
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MOV [SI][%4],DX
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MOV [SI][%6],CX
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MOV AX,SI
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POP BP
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RETFAR
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;
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;-------------------------------------------
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; LONG DIVIDE ROUTINE
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; -------------------
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; INPUT : CXDX=DIVIDEND
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; AXBX=DIVISOR
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; OUTPUT: AXBX=QUOTIENT
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; CXDX=REMAINDER
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;--------------------------------------------
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DIVIDE MOV SI,AX
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XOR SI,CX ; MSBit of SI = sign of result
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DIV04 TEST CX,CX
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JNS DIV05 ; DIVIDEND IS POSITIVE
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NEG CX
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NEG DX
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SBB CX,%0
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DIV05 TEST AX,AX
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JNS DIV06
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NEG AX
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NEG BX
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SBB AX,0
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DIV06 CALL UDIVIDE
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TEST SI,SI
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JNS DONE
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NEG AX
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NEG BX
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SBB AX,0
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NEG CX
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NEG DX
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SBB CX,%0
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DONE RET
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;
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;-------------------------------------------
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; UNSIGNED LONG DIVIDE ROUTINE
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; -------------------
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; INPUT : CXDX=DIVIDEND
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; AXBX=DIVISOR
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; OUTPUT: AXBX=QUOTIENT
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; CXDX=REMAINDER
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;--------------------------------------------
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UDIVIDE TEST AX,AX
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JNZ UDIV01
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TEST BX,BX
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JZ DIVZERO
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UDIV01 TEST DX,DX
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JNZ UDIV04
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TEST CX,CX
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JNZ UDIV04
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XOR AX,AX
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XOR BX,BX
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RET
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UDIV04 TEST AX,AX
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JNZ UDIV32
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; ; MS 16 bits of divisor = 0
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MOV AX,CX ; Upper word of dividend
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MOV CX,DX
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XOR DX,DX
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DIV BX ; Divide 0:upper by bx
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XCHG AX,CX ; CX = quotient, AX = lsw
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DIV BX ; Divide remainder:lower by bx
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MOV BX,AX ; CX = quotient MSW, AX = LSW
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MOV AX,CX
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XOR CX,CX ; remainder is 0:DX
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EXIT RET
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;
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; Divisor is 32 bits long
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; since msw of the divisor is non-zero, the upper 16 bits of the
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; quotient must be zero, and only 16 cycles are needed to divide.
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;
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UDIV32 XOR DI,DI
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MOV BP,16
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DIVLOOP SHL DX
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RCL CX
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RCL DI
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CMP DI,AX ; Fits in msw?
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JB NEXTBIT
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JNZ TOOMUCH
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CMP CX,BX ; upper words equal, check lower
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JB NEXTBIT
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TOOMUCH SUB CX,BX
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SBB DI,AX
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INC DX ; Quotient gets a 1 bit
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NEXTBIT DEC BP
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JNZ DIVLOOP
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;
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; Quotient is 0:DX, remainder is DI:CX
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;
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XOR AX,AX
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MOV BX,DX
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MOV DX,CX
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MOV CX,DI
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JMPS EXIT
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DIVZERO MOV AX,DIVBY0
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MOV %[errno],AL
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TEST %[$$ARTERM],%>01
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JZ IGNORE
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PUSH AX
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CALLFAR $_FATAL
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POP AX
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IGNORE MOV AX,>FFFF
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MOV BX,>FFFF
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POS RET
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END
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;
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; -----------------------------------------
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; COMPARE LONG
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; -----------------------------------------
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; PUSHES A RESULT BYTE
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; FF FOR LESS THAN
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; 00 FOR EQUAL
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; 01 FOR GREATER
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;
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IDT $_LCMP
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DEF $_LCMP
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$_LCMP PUSH BP
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MOV BP,SP
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XOR AX,AX
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MOV CX,[BP][%PARM3]
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MOV DX,[BP][%PARM4] ; GET L2
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SUB CX,[BP][%PARM1]
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SBB DX,[BP][%PARM2] ; COMPARE MSW
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JG LCMP06
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JL LCMP07
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TEST CX,CX
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JNZ LCMP06
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POP BP
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RETSEG
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LCMP06 INC AX
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POP BP
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RETSEG
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LCMP07 DEC AX
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POP BP
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RETSEG
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END
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;
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; -----------------------------------------
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; compare unsigned long
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; -----------------------------------------
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; PUSHES A RESULT BYTE
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; FF FOR LESS THAN
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; 00 FOR EQUAL
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; 01 FOR GREATER
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;
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IDT $_LUCMP
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DEF $_LUCMP
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DEF $_LFIXUL
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$_LFIXUL EQU $
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$_LUCMP PUSH BP
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MOV BP,SP
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XOR AX,AX
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MOV CX,[BP][%PARM3]
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MOV DX,[BP][%PARM4] ; GET L2
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CMP DX,[BP][%PARM2] ; COMPARE MSW
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JA LCMP01
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JB LCMP02
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CMP CX,[BP][%PARM1] ; COMPARE LSW
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JZ LCMP03 ; EQUAL
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JNA LCMP02
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LCMP01 MOV AL,1 ; GREATER THAN
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JMPS LCMP04
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LCMP02 MOV AL,>FF ; LESS THAN
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JMPS LCMP04
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LCMP03 XOR AX,AX ; EQUAL
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LCMP04 POP BP
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RETSEG
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END
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;
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; ---------------------------------------
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; LONG BITWISE AND
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; ---------------------------------------
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;
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IDT $_LBITAN
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DEF $_LBITAN
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$_LBITAN MOV BX,SP
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MOV AX,[BX][%PARM1-2] ; GET L1
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MOV DX,[BX][%PARM2-2] ; GET H1
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MOV CX,[BX][%PARM3-2] ; GET L2
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AND AX,CX
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MOV CX,[BX][%PARM4-2] ; GET H2
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AND DX,CX
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RETSEG
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END
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;
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; ---------------------------------------
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; LONG BITWISE INCLUSIVE OR
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; ---------------------------------------
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;
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IDT $_LBITOR
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DEF $_LBITOR
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$_LBITOR MOV BX,SP
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||
|
|
MOV AX,[BX][%PARM1-2] ; GET L1
|
||
|
|
MOV DX,[BX][%PARM2-2] ; GET H1
|
||
|
|
MOV CX,[BX][%PARM3-2] ; GET L2
|
||
|
|
OR AX,CX
|
||
|
|
MOV CX,[BX][%PARM4-2]
|
||
|
|
OR DX,CX
|
||
|
|
RETSEG
|
||
|
|
END
|
||
|
|
;
|
||
|
|
; ---------------------------------------
|
||
|
|
; LONG BITWISE INVERT
|
||
|
|
; ---------------------------------------
|
||
|
|
;
|
||
|
|
IDT $_LBITNO
|
||
|
|
DEF $_LBITNO
|
||
|
|
$_LBITNO MOV BX,SP
|
||
|
|
MOV AX,[BX][%PARM1-2] ; GET OPERAND
|
||
|
|
MOV DX,[BX][%PARM2-2]
|
||
|
|
NOT AX
|
||
|
|
NOT DX
|
||
|
|
RETSEG
|
||
|
|
END
|
||
|
|
;
|
||
|
|
; ---------------------------------------
|
||
|
|
; LONG BITWISE EXCLUSIVE OR
|
||
|
|
; ---------------------------------------
|
||
|
|
;
|
||
|
|
IDT $_LXOR
|
||
|
|
DEF $_LXOR
|
||
|
|
$_LXOR MOV BX,SP
|
||
|
|
MOV AX,[BX][%PARM1-2] ; GET L1
|
||
|
|
MOV DX,[BX][%PARM2-2] ; GET H1
|
||
|
|
MOV CX,[BX][%PARM3-2] ; GET L2
|
||
|
|
XOR AX,CX
|
||
|
|
MOV CX,[BX][%PARM4-2]
|
||
|
|
XOR DX,CX
|
||
|
|
RETSEG
|
||
|
|
END
|
||
|
|
;
|
||
|
|
; ---------------------------------------
|
||
|
|
; LONG BITWISE IMPLIES (NOT A) OR B
|
||
|
|
; ---------------------------------------
|
||
|
|
;
|
||
|
|
IDT $_LIMPL
|
||
|
|
DEF $_LIMPL
|
||
|
|
$_LIMPL MOV BX,SP
|
||
|
|
MOV AX,[BX][%PARM1-2] ; GET L1
|
||
|
|
MOV DX,[BX][%PARM2-2] ; GET H1
|
||
|
|
MOV CX,[BX][%PARM3-2] ; GET L2
|
||
|
|
NOT AX
|
||
|
|
OR AX,CX
|
||
|
|
MOV CX,[BX][%PARM4-2]
|
||
|
|
NOT DX
|
||
|
|
OR DX,CX
|
||
|
|
RETSEG
|
||
|
|
END
|
||
|
|
;
|
||
|
|
; ---------------------------------------
|
||
|
|
; LONG SHIFT RIGHT WITH ZERO FILL
|
||
|
|
; TOP OF STACK WORD CONTAINS THE COUNT
|
||
|
|
; TOP OF STACK-2 IS THE VALUE
|
||
|
|
; ---------------------------------------
|
||
|
|
;
|
||
|
|
IDT $_LSHIFR
|
||
|
|
DEF $_LSHIFR
|
||
|
|
$_LSHIFR MOV BX,SP
|
||
|
|
MOV CX,[BX][%PARM1-2] ; GET SHIFT COUNT
|
||
|
|
CMP CX,32
|
||
|
|
JNA LSHFR01
|
||
|
|
MOV CX,32 ; LIMIT TO 32
|
||
|
|
LSHFR01 MOV AX,[BX][%PARM2-2]
|
||
|
|
MOV DX,[BX][%PARM3-2]
|
||
|
|
JCXZ LSHFR03
|
||
|
|
LSHFR02 SHR DX ; SHIFT
|
||
|
|
RCR AX
|
||
|
|
LOOP LSHFR02
|
||
|
|
LSHFR03 RETSEG
|
||
|
|
END
|
||
|
|
;
|
||
|
|
; ---------------------------------------
|
||
|
|
; LONG SHIFT LEFT WITH ZERO FILL
|
||
|
|
; TOP OF STACK WORD CONTAINS THE COUNT
|
||
|
|
; TOP OF STACK-2 IS THE VALUE
|
||
|
|
; ---------------------------------------
|
||
|
|
;
|
||
|
|
IDT $_LSHIFL
|
||
|
|
DEF $_LSHIFL
|
||
|
|
$_LSHIFL MOV BX,SP
|
||
|
|
MOV CX,[BX][%PARM1-2] ; GET SHIFT COUNT
|
||
|
|
CMP CX,32
|
||
|
|
JNA LSHFL01
|
||
|
|
MOV CX,32 ; LIMIT TO 32
|
||
|
|
LSHFL01 MOV AX,[BX][%PARM2-2]
|
||
|
|
MOV DX,[BX][%PARM3-2]
|
||
|
|
JCXZ LSHFL03
|
||
|
|
LSHFL02 SHL AX ; SHIFT
|
||
|
|
RCL DX
|
||
|
|
LOOP LSHFL02
|
||
|
|
LSHFL03 RETSEG
|
||
|
|
END
|
||
|
|
;
|
||
|
|
; ---------------------------------------
|
||
|
|
; LONG SHIFT RIGHT WITH SIGN PROPOGATE
|
||
|
|
; TOP OF STACK WORD CONTAINS THE COUNT
|
||
|
|
; TOP OF STACK-2 IS THE VALUE
|
||
|
|
; ---------------------------------------
|
||
|
|
;
|
||
|
|
IDT $_LASHIF
|
||
|
|
DEF $_LASHIF
|
||
|
|
$_LASHIF MOV BX,SP
|
||
|
|
MOV CX,[BX][%PARM1-2] ; GET SHIFT COUNT
|
||
|
|
CMP CX,32
|
||
|
|
JNA LASHF01
|
||
|
|
MOV CX,32 ; LIMIT TO 32
|
||
|
|
LASHF01 MOV AX,[BX][%PARM2-2]
|
||
|
|
MOV DX,[BX][%PARM3-2]
|
||
|
|
JCXZ LASHF03
|
||
|
|
LASHF02 SAR DX ; SHIFT
|
||
|
|
RCR AX
|
||
|
|
LOOP LASHF02
|
||
|
|
LASHF03 RETSEG
|
||
|
|
END
|