simplefp.h

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// $Id: SimpleFP.h,v 1.1.2.2 2003/08/18 22:09:49 cssharp Exp $

/*									tab:4
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 * Copyright (c) 2002-2003 Intel Corporation
 * All rights reserved.
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#ifndef TOS_SIMPLEFP_H
#define TOS_SIMPLEFP_H

/* A simple fixed-point package, provides unsigned 8.8 precision (easily
   changed) */

enum { FP_BITS = 8 };		/* bits in fraction */
typedef uint16_t FPType;	/* type of fp values */
typedef uint8_t FPIntType;	/* type which can hold integral part of
                                   FPType */
typedef uint32_t FPBigger;

enum { FP_SCALE = 1UL << FP_BITS };

/* + and - can be used directly */
FPType fpMul(FPType fp1, FPType fp2)
{
  return (FPType)(((FPBigger)fp1 * fp2) >> FP_BITS);
}

FPType fpDiv(FPType fp1, FPType fp2)
{
  return (FPType)(((FPBigger)fp1 << FP_BITS) / fp2);
}

FPIntType fpRoundToZero(FPType fp)
{
  return fp >> FP_BITS;
}

FPIntType fpRoundAwayFromZero(FPType fp)
{
  return (fp + (1 << FP_BITS) - 1) >> FP_BITS;
}

FPType intToFp(FPIntType i)
{
  return i << FP_BITS;
}

#endif