Commit 2f18bbf9 authored by Tom Musta's avatar Tom Musta Committed by Peter Maydell
Browse files

softfloat: Add float32_to_uint64() 



This patch adds the float32_to_uint64() routine, which converts a
32-bit floating point number to an unsigned 64 bit number.

This contribution can be licensed under either the softfloat-2a or -2b
license.

Signed-off-by: default avatarTom Musta <tommusta@gmail.com>
Reviewed-by: default avatarPeter Maydell <peter.maydell@linaro.org>
[PMM: removed harmless but silly int64_t casts]
Signed-off-by: default avatarPeter Maydell <peter.maydell@linaro.org>
Reviewed-by: default avatarRichard Henderson <rth@twiddle.net>
parent 3c85c37f

fpu/softfloat.c

+46 −0
Original line number Diff line number Diff line
@@ -1557,6 +1557,52 @@ int64 float32_to_int64( float32 a STATUS_PARAM ) 


}



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

| Returns the result of converting the single-precision floating-point value

| `a' to the 64-bit unsigned integer format.  The conversion is

| performed according to the IEC/IEEE Standard for Binary Floating-Point

| Arithmetic---which means in particular that the conversion is rounded

| according to the current rounding mode.  If `a' is a NaN, the largest

| unsigned integer is returned.  Otherwise, if the conversion overflows, the

| largest unsigned integer is returned.  If the 'a' is negative, the result

| is rounded and zero is returned; values that do not round to zero will

| raise the inexact exception flag.

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



uint64 float32_to_uint64(float32 a STATUS_PARAM)

{

    flag aSign;

    int_fast16_t aExp, shiftCount;

    uint32_t aSig;

    uint64_t aSig64, aSigExtra;

    a = float32_squash_input_denormal(a STATUS_VAR);



    aSig = extractFloat32Frac(a);

    aExp = extractFloat32Exp(a);

    aSign = extractFloat32Sign(a);

    if ((aSign) && (aExp > 126)) {

        float_raise(float_flag_invalid STATUS_VAR);

        if (float32_is_any_nan(a)) {

            return LIT64(0xFFFFFFFFFFFFFFFF);

        } else {

            return 0;

        }

    }

    shiftCount = 0xBE - aExp;

    if (aExp) {

        aSig |= 0x00800000;

    }

    if (shiftCount < 0) {

        float_raise(float_flag_invalid STATUS_VAR);

        return LIT64(0xFFFFFFFFFFFFFFFF);

    }



    aSig64 = aSig;

    aSig64 <<= 40;

    shift64ExtraRightJamming(aSig64, 0, shiftCount, &aSig64, &aSigExtra);

    return roundAndPackUint64(aSign, aSig64, aSigExtra STATUS_VAR);

}



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

| Returns the result of converting the single-precision floating-point value

| `a' to the 64-bit two's complement integer format.  The conversion is

include/fpu/softfloat.h

+1 −0
Original line number Diff line number Diff line
@@ -295,6 +295,7 @@ int32 float32_to_int32_round_to_zero( float32 STATUS_PARAM ); 
uint32 float32_to_uint32( float32 STATUS_PARAM );

uint32 float32_to_uint32_round_to_zero( float32 STATUS_PARAM );

int64 float32_to_int64( float32 STATUS_PARAM );

uint64 float32_to_uint64(float32 STATUS_PARAM);

int64 float32_to_int64_round_to_zero( float32 STATUS_PARAM );

float64 float32_to_float64( float32 STATUS_PARAM );

floatx80 float32_to_floatx80( float32 STATUS_PARAM );