tests.c

/* Testing Code */

#include <limits.h>
#include <math.h>

/* Routines used by floation point test code */

/* Convert from bit level representation to floating point number */
float u2f(unsigned u) {
  union {
    unsigned u;
    float f;
  } a;
  a.u = u;
  return a.f;
}

/* Convert from floating point number to bit-level representation */
unsigned f2u(float f) {
  union {
    unsigned u;
    float f;
  } a;
  a.f = f;
  return a.u;
}

int test_bitAnd(int x, int y)
{
  return x&y;
}
int test_fitsBits(int x, int n)
{
  int TMin_n = -(1 << (n-1));
  int TMax_n = (1 << (n-1)) - 1;
  return x >= TMin_n && x <= TMax_n;
}
int test_isPositive(int x) {
  return x > 0;
}
int test_greatestBitPos(int x) {
    unsigned mask = 1<<31;
    if (x == 0)
 return 0;
    while (!(mask & x)) {
 mask = mask >> 1;
    }
    return mask;
}
unsigned test_float_neg(unsigned uf) {
    float f = u2f(uf);
    float nf = -f;
    if (isnan(f))
 return uf;
    else
 return f2u(nf);
}
unsigned test_float_twice(unsigned uf) {
  float f = u2f(uf);
  float tf = 2*f;
  if (isnan(f))
    return uf;
  else
    return f2u(tf);
}