/* satanh.s - Motorola 68040 FP hyperbolic arc-tangent routines (EXC) *//* Copyright 1991-1993 Wind River Systems, Inc. */	.data	.globl	_copyright_wind_river	.long	_copyright_wind_river/*modification history--------------------01f,14jun95,tpr  changed fbxx to fbxxl.01e,21jul93,kdl  added .text (SPR #2372).01d,23aug92,jcf  changed bxxx to jxx.01c,26may92,rrr  the tree shuffle01b,10jan92,kdl  added modification history; general cleanup.01a,15aug91,kdl  original version, from Motorola FPSP v2.0.*//*DESCRIPTION	__x_satanhsa 3.3 12/19/90	The entry point __x_satanh computes the inverse	hyperbolic tangent of	an input argument;  __x_satanhd does the same except for denormalized	input.	Input: Double-extended number X in location pointed to		by address register a0.	Output: The value arctanh(X) returned in floating-point register Fp0.	Accuracy and Monotonicity: The returned result is within 3 ulps in		64 significant bit, i.e. within 0.5001 ulp to 53 bits if the		result is subsequently rounded to double precision. The		result is provably monotonic in double precision.	Speed: The program __x_satanh takes approximately 270 cycles.	Algorithm:	ATANH	1. If |X| >= 1, go to 3.	2. (|X| < 1) Calculate atanh(X) by		sgn := sign(X)		y := |X|		z := 2y/(1-y)		atanh(X) := sgn * (1/2) * logp1(z)		Exit.	3. If |X| > 1, go to 5.	4. (|X| = 1) Generate infinity with an appropriate sign and		divide-by-zero by		sgn := sign(X)		atan(X) := sgn / (+0).		Exit.	5. (|X| > 1) Generate an invalid operation by 0 * infinity.		Exit.		Copyright (C) Motorola, Inc. 1990			All Rights Reserved	THIS IS UNPUBLISHED PROPRIETARY SOURCE CODE OF MOTOROLA	The copyright notice above does not evidence any	actual or intended publication of such source code.__x_satanh	IDNT	2,1 Motorola 040 Floating Point Software Package	section	8NOMANUAL*/|	xref	__x_t_dz|	xref	__x_t_operr|	xref	__x_t_frcinx|	xref	__x_t_extdnrm|	xref	__x_slognp1	.text	.globl	__x_satanhd__x_satanhd:|--ATANH(X) = X FOR DENORMALIZED X	jra 		__x_t_extdnrm	.globl	__x_satanh__x_satanh:	movel		a0@,d0	movew		a0@(4),d0	andil		#0x7FFFFFFF,d0	cmpil		#0x3FFF8000,d0	jge 		ATANHBIG|--THIS IS THE USUAL CASE, |X| < 1|--Y = |X|, Z = 2Y/(1-Y), ATANH(X) = SIGN(X) * (1/2) * LOG1P(Z).	fabsx		a0@,fp0	|...Y = |X|	fmovex		fp0,fp1	fnegx		fp1		|...-Y	faddx		fp0,fp0		|...2Y	.long 0xf23c44a2,0x3f800000	/*  fadds  &0x3F800000,fp1 */	fdivx		fp1,fp0		|...2Y/(1-Y)	movel		a0@,d0	andil		#0x80000000,d0	oril		#0x3F000000,d0	|...SIGN(X)*HALF	movel		d0,a7@-	fmovemx	fp0-fp0,a0@		|...overwrite input	movel		d1,a7@-	clrl		d1	bsrl		__x_slognp1	|...lOG1P(Z)	fmovel		a7@+,fpcr	fmuls		a7@+,fp0	jra 		__x_t_frcinxATANHBIG:	fabsx		a0@,fp0	|...|X|	.long 0xf23c4438,0x3f800000	/*  fcmps  &0x3F800000,fp0 */	fbgtl		__x_t_operr	jra 		__x_t_dz|	end