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Signed-off-by: Max Chou --- fpu/softfloat.c | 29 +++++++++++++++++++++++ include/fpu/softfloat-types.h | 5 ++++ include/fpu/softfloat.h | 43 +++++++++++++++++++++++++++++++++++ 3 files changed, 77 insertions(+) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 533f96dcda..96845e86df 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -595,6 +595,13 @@ static inline bool fmt_has_nan_encoding(const FloatFmt= *fmt) .frac_shift =3D (-F - 1) & 63, \ .round_mask =3D (1ull << ((-F - 1) & 63)) - 1 =20 +static const FloatFmt float4_e2m1_params =3D { + FLOAT_PARAMS(2, 1), + .no_infinity =3D true, + .limited_nan =3D true, + .normal_frac_max =3D NORMAL_FRAC_MAX_ALL, +}; + static const FloatFmt float8_e4m3_params =3D { FLOAT_PARAMS(4, 3), .no_infinity =3D true, @@ -663,6 +670,11 @@ static void unpack_raw64(FloatParts64 *r, const FloatF= mt *fmt, uint64_t raw) }; } =20 +static void QEMU_FLATTEN float4_e2m1_unpack_raw(FloatParts64 *p, float4_e2= m1 f) +{ + unpack_raw64(p, &float4_e2m1_params, f); +} + static void QEMU_FLATTEN float8_e4m3_unpack_raw(FloatParts64 *p, float8_e4= m3 f) { unpack_raw64(p, &float8_e4m3_params, f); @@ -1745,6 +1757,13 @@ static const uint16_t rsqrt_tab[128] =3D { * Pack/unpack routines with a specific FloatFmt. */ =20 +static void float4_e2m1_unpack_canonical(FloatParts64 *p, float4_e2m1 f, + float_status *s) +{ + float4_e2m1_unpack_raw(p, f); + parts_canonicalize(p, s, &float4_e2m1_params); +} + static void float8_e4m3_unpack_canonical(FloatParts64 *p, float8_e4m3 f, float_status *s) { @@ -2938,6 +2957,16 @@ static void parts_float_to_float_widen(FloatParts128= *a, FloatParts64 *b, } } =20 +float8_e4m3 float4_e2m1_to_float8_e4m3(float4_e2m1 a, float_status *s) +{ + FloatParts64 p; + + float4_e2m1_unpack_canonical(&p, a, s); + parts_float_to_float(&p, s); + + return float8_e4m3_round_pack_canonical(&p, s, &float8_e4m3_params, fa= lse); +} + bfloat16 float8_e4m3_to_bfloat16(float8_e4m3 a, float_status *s) { FloatParts64 p; diff --git a/include/fpu/softfloat-types.h b/include/fpu/softfloat-types.h index b781bf10b7..f8cadffff4 100644 --- a/include/fpu/softfloat-types.h +++ b/include/fpu/softfloat-types.h @@ -131,6 +131,11 @@ typedef uint8_t float8_e5m2; #define const_float8_e4m3(x) (x) #define const_float8_e5m2(x) (x) =20 +typedef uint8_t float4_e2m1; +#define float4_e2m1_val(x) ((x) & 0xf) +#define make_float4_e2m1(x) ((x) & 0xf) +#define const_float4_e2m1(x) ((x) & 0xf) + /* * Software IEC/IEEE floating-point underflow tininess-detection mode. */ diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h index 7abbf92b7e..888efed288 100644 --- a/include/fpu/softfloat.h +++ b/include/fpu/softfloat.h @@ -200,6 +200,8 @@ float8_e5m2 bfloat16_to_float8_e5m2(bfloat16, bool satu= rate, float_status *statu float8_e4m3 float32_to_float8_e4m3(float32, bool saturate, float_status *s= tatus); float8_e5m2 float32_to_float8_e5m2(float32, bool saturate, float_status *s= tatus); =20 +float8_e4m3 float4_e2m1_to_float8_e4m3(float4_e2m1, float_status *status); + /*------------------------------------------------------------------------= ---- | Software OCP operations. *-------------------------------------------------------------------------= ---*/ @@ -270,6 +272,47 @@ static inline bool float8_e5m2_is_normal(float8_e5m2 a) return (((float8_e5m2_val(a) >> 2) + 1) & 0x1f) >=3D 2; } =20 +static inline bool float4_e2m1_is_quiet_nan(float4_e2m1 a, float_status *s= tatus) +{ + return false; +} + +static inline bool float4_e2m1_is_signaling_nan(float4_e2m1 a, float_statu= s *status) +{ + return false; +} + +static inline bool float4_e2m1_is_any_nan(float4_e2m1 a) +{ + return false; +} + +static inline bool float4_e2m1_is_neg(float4_e2m1 a) +{ + return float4_e2m1_val(a) >> 3; +} + +static inline bool float4_e2m1_is_infinity(float4_e2m1 a) +{ + return false; +} + +static inline bool float4_e2m1_is_zero(float4_e2m1 a) +{ + return (float4_e2m1_val(a) & 0x7) =3D=3D 0; +} + +static inline bool float4_e2m1_is_zero_or_denormal(float4_e2m1 a) +{ + return (float4_e2m1_val(a) & 0x6) =3D=3D 0; +} + +static inline bool float4_e2m1_is_normal(float4_e2m1 a) +{ + uint8_t em =3D float4_e2m1_val(a) & 0x7; + return em >=3D 0x2 && em <=3D 0x7; +} + /*------------------------------------------------------------------------= ---- | Software half-precision conversion routines. *-------------------------------------------------------------------------= ---*/ --=20 2.52.0