/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */

/*
 * File:   main.c
 * Author: Peter Heusch
 *
 * Created on 3. April 2018, 11:19
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>

#define  SIGN(x) (x>>31);
#define  MANT(x) (x&0x7FFFFF);
#define  EXPO(x) ((x>>23)&0xFF);
#define SPLIT(x, s, m, e) do {    \
  s = SIGN(x);                    \
  m = MANT(x);                    \
  e = EXPO(x);                    \
  if ( e != 0x00 && e != 0xFF ) { \
    m |= 0x800000;                \
  }                               \
} while ( 0 )

#define BUILD(x, s, m, e) do {               \
    x = (s << 31) | (e<<23) | (m&0x7FFFFF);  \
} while ( 0 )                                \


float foo(float *a, float *b) {
    uint32_t ia = *(unsigned int *) a;
    uint32_t ib = *(unsigned int *) b;
    uint32_t result = 0;
    int signa, signb, signr;
    int manta, mantb, mantr;
    int expoa, expob, expor;
    SPLIT(ia, signa, manta, expoa);
    SPLIT(ib, signb, mantb, expob);
    printf("%d %d %d \n", signa, manta, expoa);
    printf("%d %d %d \n", signb, mantb, expob);
    // Berechnen Sie hier signr mantr und expor!
    if (expoa == expob) {
        signr = (signa + signb);
        mantr = (manta + mantb) >> 1;
        expor = expoa + 1;
    } else {
        int shift = expoa - expob;

        if (shift > 0) {
            expob = expob + shift;
            mantb = mantb>>shift;
            printf("%d %d\n", expob, mantb);
            signr = (signa + signb);
            mantr = (manta + mantb);
            expor = expoa;
        }
        if (shift < 0) {
            shift *= -1;
            printf("%d \n", shift);
            expoa = expoa + shift;
            manta = manta >> shift;
            signr = (signa + signb);
            mantr = (manta + mantb);
            expor = expob;
        }
    }
    BUILD(result, signr, mantr, expor);
    return *(float *) &result;
}

/*
 *
 */

int main(int argc, char** argv) {
    // Nebenbedingungen im Test:
    // Die Eingaben sind Zahlen im Bereich [-10.0...10.0]
    // Bei der Division kommt die 0 als Divisor nicht vor!
    float f = 1.2;
    float g = 8.9;
    float h = foo(&f, &g);
    printf("%lf %lf %lf", f, g, h);
    return (EXIT_SUCCESS);
}