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 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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 */
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 */
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#include "sftypes.h"
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#include "conversion.h"
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float64 convertFloat32ToFloat64(float32 a)
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{
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    float64 result;
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    __u64 mant;
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    result.parts.sign = a.parts.sign;
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    result.parts.mantisa = a.parts.mantisa;
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    result.parts.mantisa <<= (FLOAT64_MANTISA_SIZE - FLOAT32_MANTISA_SIZE );
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    if ((isFloat32Infinity(a))||(isFloat32NaN(a))) {
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        result.parts.exp = 0x7FF;
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        /* TODO; check if its correct for SigNaNs*/
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        return result;
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    };
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    result.parts.exp = a.parts.exp + ( (int)FLOAT64_BIAS - FLOAT32_BIAS );
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    if (a.parts.exp == 0) {
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        /* normalize denormalized numbers */
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        if (result.parts.mantisa == 0ll) { /* fix zero */
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            result.parts.exp = 0ll;
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            return result;
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        }
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        mant = result.parts.mantisa;
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        while (!(mant & (0x10000000000000ll))) {
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            mant <<= 1;
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            --result.parts.exp;
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        };
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        result.parts.mantisa = mant;
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    };
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    return result;
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};
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float32 convertFloat64ToFloat32(float64 a)
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{
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    float32 result;
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    __s32 exp;
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    __u64 mant;
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    result.parts.sign = a.parts.sign;
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    if (isFloat64NaN(a)) {
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        result.parts.exp = 0xFF;
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        if (isFloat64SigNaN(a)) {
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            result.parts.mantisa = 0x800000; /* set first bit of mantisa nonzero */
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            return result;
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        }
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        result.parts.mantisa = 0x1; /* mantisa nonzero but its first bit is zero */
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        return result;
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    };
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    if (isFloat64Infinity(a)) {
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        result.parts.mantisa = 0;
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        result.parts.exp = 0xFF;
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        return result;
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    };
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    exp = (int)a.parts.exp - FLOAT64_BIAS + FLOAT32_BIAS;
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    if (exp >= 0xFF) {
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        /*FIXME: overflow*/
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        result.parts.mantisa = 0;
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        result.parts.exp = 0xFF;
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        return result;
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    } else if (exp <= 0 ) {
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        /* underflow or denormalized */
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        result.parts.exp = 0;
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        exp *= -1; 
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        if (exp > FLOAT32_MANTISA_SIZE ) {
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            /* FIXME: underflow */
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            result.parts.mantisa = 0;
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            return result;
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        };
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        /* denormalized */
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        mant = result.parts.mantisa >> 1;
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        mant |= 0x10000000000000ll; /* denormalize and set hidden bit */
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        while (exp > 0) {
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            --exp;
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            mant >>= 1;
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        };
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        result.parts.mantisa = mant;
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        return result;
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    };
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    result.parts.exp = exp;
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    result.parts.mantisa = a.parts.mantisa >> (FLOAT64_MANTISA_SIZE - FLOAT32_MANTISA_SIZE);
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    return result;
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};
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