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| Returns the binary exponential of the single-precision floating-point value

| `a'. The operation is performed according to the IEC/IEEE Standard for

| Binary Floating-Point Arithmetic.

|

| Uses the following identities:

|

| 1. -------------------------------------------------------------------------

|      x    x*ln(2)

|     2  = e

|

| 2. -------------------------------------------------------------------------

|                      2     3     4     5           n

|      x        x     x     x     x     x           x

|     e  = 1 + --- + --- + --- + --- + --- + ... + --- + ...

|               1!    2!    3!    4!    5!          n!

*----------------------------------------------------------------------------*/

static const float64 float32_exp2_coefficients[15] =

{

    make_float64( 0x3ff0000000000000ll ), /*  1 */

    make_float64( 0x3fe0000000000000ll ), /*  2 */

    make_float64( 0x3fc5555555555555ll ), /*  3 */

    make_float64( 0x3fa5555555555555ll ), /*  4 */

    make_float64( 0x3f81111111111111ll ), /*  5 */

    make_float64( 0x3f56c16c16c16c17ll ), /*  6 */

    make_float64( 0x3f2a01a01a01a01all ), /*  7 */

    make_float64( 0x3efa01a01a01a01all ), /*  8 */

    make_float64( 0x3ec71de3a556c734ll ), /*  9 */

    make_float64( 0x3e927e4fb7789f5cll ), /* 10 */

    make_float64( 0x3e5ae64567f544e4ll ), /* 11 */

    make_float64( 0x3e21eed8eff8d898ll ), /* 12 */

    make_float64( 0x3de6124613a86d09ll ), /* 13 */

    make_float64( 0x3da93974a8c07c9dll ), /* 14 */

    make_float64( 0x3d6ae7f3e733b81fll ), /* 15 */

};

float32 float32_exp2( float32 a STATUS_PARAM )

{

    flag aSign;

    int16 aExp;

    bits32 aSig;

    float64 r, x, xn;

    int i;

    aSig = extractFloat32Frac( a );

    aExp = extractFloat32Exp( a );

    aSign = extractFloat32Sign( a );

    if ( aExp == 0xFF) {

        if ( aSig ) return propagateFloat32NaN( a, float32_zero STATUS_VAR );

        return (aSign) ? float32_zero : a;

    }

    if (aExp == 0) {

        if (aSig == 0) return float32_one;

    }

    float_raise( float_flag_inexact STATUS_VAR);

    /* ******************************* */

    /* using float64 for approximation */

    /* ******************************* */

    x = float32_to_float64(a STATUS_VAR);

    x = float64_mul(x, float64_ln2 STATUS_VAR);

    xn = x;

    r = float64_one;

    for (i = 0 ; i < 15 ; i++) {

        float64 f;

        f = float64_mul(xn, float32_exp2_coefficients[i] STATUS_VAR);

        r = float64_add(r, f STATUS_VAR);

        xn = float64_mul(xn, x STATUS_VAR);

    }

    return float64_to_float32(r, status);

}

/*----------------------------------------------------------------------------