Commit 21381dcf authored by Matus Kysel's avatar Matus Kysel Committed by Richard Henderson
Browse files

softfp: Added hardfloat conversion from float32 to float64 

Reintroduce float32_to_float64 that was removed here:
https://lists.gnu.org/archive/html/qemu-devel/2018-04/msg00455.html



 - nbench test it not actually calling this function at all
 - SPECS 2006 significat number of tests impoved their runtime, just
   few of them showed small slowdown

Reviewed-by: default avatarRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: default avatarMatus Kysel <mkysel@tachyum.com>
Message-Id: <20191017142133.59439-1-mkysel@tachyum.com>
[rth: Add comment about impossible inexact exceptions.]
Signed-off-by: default avatarRichard Henderson <richard.henderson@linaro.org>
parent 16884391

fpu/softfloat.c

+18 −1
Original line number Diff line number Diff line
@@ -1920,13 +1920,30 @@ float16 float32_to_float16(float32 a, bool ieee, float_status *s) 
    return float16a_round_pack_canonical(pr, s, fmt16);

}



float64 float32_to_float64(float32 a, float_status *s)

static float64 QEMU_SOFTFLOAT_ATTR

soft_float32_to_float64(float32 a, float_status *s)

{

    FloatParts p = float32_unpack_canonical(a, s);

    FloatParts pr = float_to_float(p, &float64_params, s);

    return float64_round_pack_canonical(pr, s);

}



float64 float32_to_float64(float32 a, float_status *s)

{

    if (likely(float32_is_normal(a))) {

        /* Widening conversion can never produce inexact results.  */

        union_float32 uf;

        union_float64 ud;

        uf.s = a;

        ud.h = uf.h;

        return ud.s;

    } else if (float32_is_zero(a)) {

        return float64_set_sign(float64_zero, float32_is_neg(a));

    } else {

        return soft_float32_to_float64(a, s);

    }

}



float16 float64_to_float16(float64 a, bool ieee, float_status *s)

{

    const FloatFmt *fmt16 = ieee ? &float16_params : &float16_params_ahp;