zc030x_fp.h

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#ifndef h_Zc030x_FPU_h
#define h_Zc030x_FPU_h

/* Include kernel types */
#include <linux/types.h>

/* This code is greatly inspired from 
  Author:  William A. Rossi
           175 Burnt Hill Rd
           Hope, RI 02831
    http://www.rossi.com/sqr2.htm
           [e-mail]
           
  It was in public domain, in C++ and using BIGINT library
I removed BIGINT library, make it C based, and used 64 bits integers 
to emulate floats (with 2^-18 precision, not so bad) */

/* The maximum number of valid digit is 19 */
#define MaxDigits   19
/* The half number of valid digits is 9 */
#define HalfDigits  9

/* Define the FPNum structure */
typedef struct 
{
    uint64_t    Mant;       /* Easy to guess, this is the mantissa */
    int16_t     Exp;        /* This is the exponent */
    int8_t      Sign;       /* Sign 1 or -1 (0 make this number invalid) */
} FPNum;

/* Initialize a FPNum from a char (very easy) */
void InitFPNum(FPNum * this, const char * Number);

/* Get a FPNum output as string */
void GetFPNumAsString(FPNum * this, char * output);

/* Get a number as an Int64 */
int64_t GetFPNumAsInt(FPNum * this);

/* Add 2 FPNum numbers */
FPNum Add(const FPNum a, const FPNum b);

/* Multiply 2 FPNum numbers */
FPNum Mul(const FPNum a, const FPNum b);

/* Create a FPNum from an int */
const FPNum CreateFPNumFromInt(int32_t Number);


#endif