; File: FixMath.a
;
; Version 2.0a3
;
; Copyright 1984, 1985, 1986 Apple Computer, Inc. All Rights Reserved
;

	INCLUDE 'SysEqu.a'
	
; This file is the implementation of the FixMath calls.


; FUNCTION FixDiv   (x, y: Fixed): Fixed;     { returns x/y, signed }
;
; FUNCTION FracDiv  (x, y: Fracd): Fracd;     { returns x/y }
;
; FUNCTION FracMul  (x, y: Fracd): Fracd;     { returns x*y }
;
; FUNCTION FracSqrt (x: Fracd)	 : Fracd;     { returns square root of x }
;
; FUNCTION FracSin  (x: Fixed)	 : Fracd;     { returns Sin(x) }
;
; FUNCTION FracCos  (x: Fixed)	 : Fracd;     { returns Cos(x) }
;
; Type Fixed is 32-bit binary fixed-point with binary point between
; high and low words.  Sign is kept a la 2's-complement.
; Type double is 64-bit IEEE binary floating point.
; Type Fracd is 32-bit binary fixed point-point with binary point
; after leading bits.  Sign is kept a la 2's-complement.
;
; Exceptional cases:
;       Fixed overflow is set to $7FFFFFFF when positive, $80000000 when
;	        negative.
;       Division by zero yields $7FFFFFFF when x is positive or zero,
;	        and $80000000 when x is negative.
;
; Calling conventions:
;       Fixed results are returned in D0.32, double results in D0-D1.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;

;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
; There are two flavors of multiply, FracMul and FixMul.  FracMul uses the
; top 35 bits of the 64-bit product: the top two are shifted off the left,
; the the last bit is used for rounding.  FixMul uses the middle 32 bits
; of the product, with the attendant overflow checks, and rounds with a
; 32nd bit.
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;


;128K Rom Fixmath Traps with auto-pop bit set

_NFracDiv	OPWORD	$AC4B
_NFixDiv	OPWORD	$AC4D
_NFracCos	OPWORD	$AC47
_NFracSin	OPWORD	$AC48
_NFracMul	OPWORD	$AC4A
_NFracSqrt	OPWORD	$AC49


FixMath	PROC EXPORT	

		EXPORT    FracMul
        EXPORT    FracDiv
        EXPORT    FixDiv
        EXPORT    FracSqrt
        EXPORT    FracSin
        EXPORT    FracCos

FracMul
		_NFracMul	;the trap
		;will return to caller
FracDiv
		_NFracDiv	;the trap
		;will return to caller
FixDiv
		_NFixDiv	;the trap
		;will return to caller
FracSqrt
		_NFracSqrt	;the trap
		;will return to caller
FracCos
		_NFracCos	;the trap
		;will return to caller
FracSin
		_NFracSin	;the trap
		;will return to caller

	END