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Import of OpenBSD 4.2 release kernel tree with initial code to support 
Jornada 720/728, StrongARM 1110-based handheld PC.
At this point kernel roots on NFS and boots into vfs_mountroot() and traps.
What is supported:
- glass console, Jornada framebuffer (jfb) works in 16bpp direct color mode
(needs some palette tweaks for non black/white/blue colors, i think)
- saic, SA11x0 interrupt controller (needs cleanup)
- sacom, SA11x0 UART (supported only as boot console for now)
- SA11x0 GPIO controller fully supported (but can't handle multiple interrupt
handlers on one gpio pin)
- sassp, SSP port on SA11x0 that attaches spibus
- Jornada microcontroller (jmcu) to control kbd, battery, etc throught
the SPI bus (wskbd attaches on jmcu, but not tested)
- tod functions seem work
- initial code for SA-1111 (chip companion) : this is TODO

Next important steps, i think:
- gpio and intc on sa1111
- pcmcia support for sa11x0 (and sa1111 help logic)
- REAL root on nfs when we have PCMCIA support (we may use any of supported pccard NICs)
- root on wd0! (using already supported PCMCIA-ATA)

/*	$OpenBSD: sfsqrt.c,v 1.7 2003/04/10 17:27:59 mickey Exp $	*/
/*
  (c) Copyright 1986 HEWLETT-PACKARD COMPANY
  To anyone who acknowledges that this file is provided "AS IS"
  without any express or implied warranty:
      permission to use, copy, modify, and distribute this file
  for any purpose is hereby granted without fee, provided that
  the above copyright notice and this notice appears in all
  copies, and that the name of Hewlett-Packard Company not be
  used in advertising or publicity pertaining to distribution
  of the software without specific, written prior permission.
  Hewlett-Packard Company makes no representations about the
  suitability of this software for any purpose.
*/
/* @(#)sfsqrt.c: Revision: 1.9.88.1 Date: 93/12/07 15:07:13 */

#include "float.h"
#include "sgl_float.h"

/*
 *  Single Floating-point Square Root
 */

/*ARGSUSED*/
int
sgl_fsqrt(srcptr, null, dstptr, status)
	sgl_floating_point *srcptr, *null, *dstptr;
	unsigned int *status;
{
	register unsigned int src, result;
	register int src_exponent, newbit, sum;
	register int guardbit = FALSE, even_exponent;

	src = *srcptr;
	/*
	 * check source operand for NaN or infinity
	 */
	if ((src_exponent = Sgl_exponent(src)) == SGL_INFINITY_EXPONENT) {
		/*
		 * is signaling NaN?
		 */
		if (Sgl_isone_signaling(src)) {
			/* trap if INVALIDTRAP enabled */
			if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
			/* make NaN quiet */
			Set_invalidflag();
			Sgl_set_quiet(src);
		}
		/*
		 * Return quiet NaN or positive infinity.
		 *  Fall thru to negative test if negative infinity.
		 */
		if (Sgl_iszero_sign(src) || Sgl_isnotzero_mantissa(src)) {
			*dstptr = src;
			return(NOEXCEPTION);
		}
	}

	/*
	 * check for zero source operand
	 */
	if (Sgl_iszero_exponentmantissa(src)) {
		*dstptr = src;
		return(NOEXCEPTION);
	}

	/*
	 * check for negative source operand
	 */
	if (Sgl_isone_sign(src)) {
		/* trap if INVALIDTRAP enabled */
		if (Is_invalidtrap_enabled()) return(INVALIDEXCEPTION);
		/* make NaN quiet */
		Set_invalidflag();
		Sgl_makequietnan(src);
		*dstptr = src;
		return(NOEXCEPTION);
	}

	/*
	 * Generate result
	 */
	if (src_exponent > 0) {
		even_exponent = Sgl_hidden(src);
		Sgl_clear_signexponent_set_hidden(src);
	}
	else {
		/* normalize operand */
		Sgl_clear_signexponent(src);
		src_exponent++;
		Sgl_normalize(src,src_exponent);
		even_exponent = src_exponent & 1;
	}
	if (even_exponent) {
		/* exponent is even */
		/* Add comment here.  Explain why odd exponent needs correction */
		Sgl_leftshiftby1(src);
	}
	/*
	 * Add comment here.  Explain following algorithm.
	 *
	 * Trust me, it works.
	 *
	 */
	Sgl_setzero(result);
	newbit = 1 << SGL_P;
	while (newbit && Sgl_isnotzero(src)) {
		Sgl_addition(result,newbit,sum);
		if(sum <= Sgl_all(src)) {
			/* update result */
			Sgl_addition(result,(newbit<<1),result);
			Sgl_subtract(src,sum,src);
		}
		Sgl_rightshiftby1(newbit);
		Sgl_leftshiftby1(src);
	}
	/* correct exponent for pre-shift */
	if (even_exponent) {
		Sgl_rightshiftby1(result);
	}

	/* check for inexact */
	if (Sgl_isnotzero(src)) {
		if (!even_exponent & Sgl_islessthan(result,src))
			Sgl_increment(result);
		guardbit = Sgl_lowmantissa(result);
		Sgl_rightshiftby1(result);

		/*  now round result  */
		switch (Rounding_mode()) {
		case ROUNDPLUS:
		     Sgl_increment(result);
		     break;
		case ROUNDNEAREST:
		     /* stickybit is always true, so guardbit
		      * is enough to determine rounding */
		     if (guardbit) {
			Sgl_increment(result);
		     }
		     break;
		}
		/* increment result exponent by 1 if mantissa overflowed */
		if (Sgl_isone_hiddenoverflow(result)) src_exponent+=2;

		if (Is_inexacttrap_enabled()) {
			Sgl_set_exponent(result,
			 ((src_exponent-SGL_BIAS)>>1)+SGL_BIAS);
			*dstptr = result;
			return(INEXACTEXCEPTION);
		}
		else Set_inexactflag();
	}
	else {
		Sgl_rightshiftby1(result);
	}
	Sgl_set_exponent(result,((src_exponent-SGL_BIAS)>>1)+SGL_BIAS);
	*dstptr = result;
	return(NOEXCEPTION);
}