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This commit introduces [float16|bfloat16|float32|float64|float128]_nan_is_snan that determine if a NaN is signaling. Suggested-by: Richard Henderson Signed-off-by: Max Chou Reviewed-by: Richard Henderson Reviewed-by: Chao Liu Signed-off-by: Richard Henderson Message-ID: <20260204051756.667397-3-max.chou@sifive.com> --- fpu/softfloat-specialize.c.inc | 192 ++++++++++++++------------------- 1 file changed, 80 insertions(+), 112 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index ba4fa08b7b..7d2515c1fa 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -226,6 +226,19 @@ floatx80 floatx80_default_inf(bool zSign, float_status= *status) return packFloatx80(zSign, 0x7fff, z ? 0 : (1ULL << 63)); } =20 +/*------------------------------------------------------------------------= ---- +| Determine if a float16 NaN is signaling NaN. +*-------------------------------------------------------------------------= ---*/ + +static bool float16_nan_is_snan(float16 a, float_status *status) +{ + if (no_signaling_nans(status)) { + return false; + } + bool frac_msb_is_one =3D (a >> 9) & 1; + return frac_msb_is_one =3D=3D snan_bit_is_one(status); +} + /*------------------------------------------------------------------------= ---- | Returns 1 if the half-precision floating-point value `a' is a quiet | NaN; otherwise returns 0. @@ -233,36 +246,7 @@ floatx80 floatx80_default_inf(bool zSign, float_status= *status) =20 bool float16_is_quiet_nan(float16 a_, float_status *status) { - if (no_signaling_nans(status)) { - return float16_is_any_nan(a_); - } else { - uint16_t a =3D float16_val(a_); - if (snan_bit_is_one(status)) { - return (((a >> 9) & 0x3F) =3D=3D 0x3E) && (a & 0x1FF); - } else { - - return ((a >> 9) & 0x3F) =3D=3D 0x3F; - } - } -} - -/*------------------------------------------------------------------------= ---- -| Returns 1 if the bfloat16 value `a' is a quiet -| NaN; otherwise returns 0. -*-------------------------------------------------------------------------= ---*/ - -bool bfloat16_is_quiet_nan(bfloat16 a_, float_status *status) -{ - if (no_signaling_nans(status)) { - return bfloat16_is_any_nan(a_); - } else { - uint16_t a =3D a_; - if (snan_bit_is_one(status)) { - return (((a >> 6) & 0x1FF) =3D=3D 0x1FE) && (a & 0x3F); - } else { - return ((a >> 6) & 0x1FF) =3D=3D 0x1FF; - } - } + return float16_is_any_nan(a_) && !float16_nan_is_snan(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -272,35 +256,51 @@ bool bfloat16_is_quiet_nan(bfloat16 a_, float_status = *status) =20 bool float16_is_signaling_nan(float16 a_, float_status *status) { - if (no_signaling_nans(status)) { - return 0; - } else { - uint16_t a =3D float16_val(a_); - if (snan_bit_is_one(status)) { - return ((a >> 9) & 0x3F) =3D=3D 0x3F; - } else { - return (((a >> 9) & 0x3F) =3D=3D 0x3E) && (a & 0x1FF); - } - } + return float16_is_any_nan(a_) && float16_nan_is_snan(a_, status); } =20 /*------------------------------------------------------------------------= ---- -| Returns 1 if the bfloat16 value `a' is a signaling -| NaN; otherwise returns 0. +| Determine if a bfloat16 NaN is signaling NaN. +*-------------------------------------------------------------------------= ---*/ + +static bool bfloat16_nan_is_snan(bfloat16 a, float_status *status) +{ + if (no_signaling_nans(status)) { + return false; + } + bool frac_msb_is_one =3D (a >> 6) & 1; + return frac_msb_is_one =3D=3D snan_bit_is_one(status); +} + +/*------------------------------------------------------------------------= ---- +| Returns 1 if the bfloat16 value `a' is a quiet NaN; otherwise returns 0. +*-------------------------------------------------------------------------= ---*/ + +bool bfloat16_is_quiet_nan(bfloat16 a_, float_status *status) +{ + return bfloat16_is_any_nan(a_) && !bfloat16_nan_is_snan(a_, status); +} + +/*------------------------------------------------------------------------= ---- +| Returns 1 if the bfloat16 value `a' is a signaling NaN; otherwise return= s 0. *-------------------------------------------------------------------------= ---*/ =20 bool bfloat16_is_signaling_nan(bfloat16 a_, float_status *status) +{ + return bfloat16_is_any_nan(a_) && bfloat16_nan_is_snan(a_, status); +} + +/*------------------------------------------------------------------------= ---- +| Determine if a float32 NaN is signaling NaN. +*-------------------------------------------------------------------------= ---*/ + +static bool float32_nan_is_snan(float32 a, float_status *status) { if (no_signaling_nans(status)) { - return 0; - } else { - uint16_t a =3D a_; - if (snan_bit_is_one(status)) { - return ((a >> 6) & 0x1FF) =3D=3D 0x1FF; - } else { - return (((a >> 6) & 0x1FF) =3D=3D 0x1FE) && (a & 0x3F); - } + return false; } + bool frac_msb_is_one =3D (a >> 22) & 1; + return frac_msb_is_one =3D=3D snan_bit_is_one(status); } =20 /*------------------------------------------------------------------------= ---- @@ -310,16 +310,7 @@ bool bfloat16_is_signaling_nan(bfloat16 a_, float_stat= us *status) =20 bool float32_is_quiet_nan(float32 a_, float_status *status) { - if (no_signaling_nans(status)) { - return float32_is_any_nan(a_); - } else { - uint32_t a =3D float32_val(a_); - if (snan_bit_is_one(status)) { - return (((a >> 22) & 0x1FF) =3D=3D 0x1FE) && (a & 0x003FFFFF); - } else { - return ((uint32_t)(a << 1) >=3D 0xFF800000); - } - } + return float32_is_any_nan(a_) && !float32_nan_is_snan(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -328,17 +319,21 @@ bool float32_is_quiet_nan(float32 a_, float_status *s= tatus) *-------------------------------------------------------------------------= ---*/ =20 bool float32_is_signaling_nan(float32 a_, float_status *status) +{ + return float32_is_any_nan(a_) && float32_nan_is_snan(a_, status); +} + +/*------------------------------------------------------------------------= ---- +| Determine if a float64 NaN is signaling NaN. +*-------------------------------------------------------------------------= ---*/ + +static bool float64_nan_is_snan(float64 a, float_status *status) { if (no_signaling_nans(status)) { - return 0; - } else { - uint32_t a =3D float32_val(a_); - if (snan_bit_is_one(status)) { - return ((uint32_t)(a << 1) >=3D 0xFF800000); - } else { - return (((a >> 22) & 0x1FF) =3D=3D 0x1FE) && (a & 0x003FFFFF); - } + return false; } + bool frac_msb_is_one =3D (a >> 51) & 1; + return frac_msb_is_one =3D=3D snan_bit_is_one(status); } =20 /*------------------------------------------------------------------------= ---- @@ -348,17 +343,7 @@ bool float32_is_signaling_nan(float32 a_, float_status= *status) =20 bool float64_is_quiet_nan(float64 a_, float_status *status) { - if (no_signaling_nans(status)) { - return float64_is_any_nan(a_); - } else { - uint64_t a =3D float64_val(a_); - if (snan_bit_is_one(status)) { - return (((a >> 51) & 0xFFF) =3D=3D 0xFFE) - && (a & 0x0007FFFFFFFFFFFFULL); - } else { - return ((a << 1) >=3D 0xFFF0000000000000ULL); - } - } + return float64_is_any_nan(a_) && !float64_nan_is_snan(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -368,17 +353,7 @@ bool float64_is_quiet_nan(float64 a_, float_status *st= atus) =20 bool float64_is_signaling_nan(float64 a_, float_status *status) { - if (no_signaling_nans(status)) { - return 0; - } else { - uint64_t a =3D float64_val(a_); - if (snan_bit_is_one(status)) { - return ((a << 1) >=3D 0xFFF0000000000000ULL); - } else { - return (((a >> 51) & 0xFFF) =3D=3D 0xFFE) - && (a & UINT64_C(0x0007FFFFFFFFFFFF)); - } - } + return float64_is_any_nan(a_) && float64_nan_is_snan(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -444,6 +419,19 @@ floatx80 floatx80_silence_nan(floatx80 a, float_status= *status) return a; } =20 +/*------------------------------------------------------------------------= ---- +| Determine if a float128 NaN is signaling NaN. +*-------------------------------------------------------------------------= ---*/ + +static bool float128_nan_is_snan(float128 a, float_status *status) +{ + if (no_signaling_nans(status)) { + return false; + } + bool frac_msb_is_one =3D (a.high >> 47) & 1; + return frac_msb_is_one =3D=3D snan_bit_is_one(status); +} + /*------------------------------------------------------------------------= ---- | Returns 1 if the quadruple-precision floating-point value `a' is a quiet | NaN; otherwise returns 0. @@ -451,17 +439,7 @@ floatx80 floatx80_silence_nan(floatx80 a, float_status= *status) =20 bool float128_is_quiet_nan(float128 a, float_status *status) { - if (no_signaling_nans(status)) { - return float128_is_any_nan(a); - } else { - if (snan_bit_is_one(status)) { - return (((a.high >> 47) & 0xFFFF) =3D=3D 0xFFFE) - && (a.low || (a.high & 0x00007FFFFFFFFFFFULL)); - } else { - return ((a.high << 1) >=3D 0xFFFF000000000000ULL) - && (a.low || (a.high & 0x0000FFFFFFFFFFFFULL)); - } - } + return float128_is_any_nan(a) && !float128_nan_is_snan(a, status); } =20 /*------------------------------------------------------------------------= ---- @@ -471,15 +449,5 @@ bool float128_is_quiet_nan(float128 a, float_status *s= tatus) =20 bool float128_is_signaling_nan(float128 a, float_status *status) { - if (no_signaling_nans(status)) { - return 0; - } else { - if (snan_bit_is_one(status)) { - return ((a.high << 1) >=3D 0xFFFF000000000000ULL) - && (a.low || (a.high & 0x0000FFFFFFFFFFFFULL)); - } else { - return (((a.high >> 47) & 0xFFFF) =3D=3D 0xFFFE) - && (a.low || (a.high & UINT64_C(0x00007FFFFFFFFFFF))); - } - } + return float128_is_any_nan(a) && float128_nan_is_snan(a, status); } --=20 2.43.0