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This commit introduces internal helper functions: [float16|bfloat16|float32|float64]_is_snan_internal that determine if a NaN is signaling. Suggested-by: Richard Henderson Signed-off-by: Max Chou --- fpu/softfloat-specialize.c.inc | 152 +++++++++++++++++---------------- 1 file changed, 78 insertions(+), 74 deletions(-) diff --git a/fpu/softfloat-specialize.c.inc b/fpu/softfloat-specialize.c.inc index ba4fa08b7b..ce7315c996 100644 --- a/fpu/softfloat-specialize.c.inc +++ b/fpu/softfloat-specialize.c.inc @@ -225,6 +225,22 @@ floatx80 floatx80_default_inf(bool zSign, float_status= *status) bool z =3D status->floatx80_behaviour & floatx80_default_inf_int_bit_i= s_zero; return packFloatx80(zSign, 0x7fff, z ? 0 : (1ULL << 63)); } +/*------------------------------------------------------------------------= ---- +| Internal helper: Determine if float16 NaN is signaling. +*-------------------------------------------------------------------------= ---*/ + +static bool float16_is_snan_internal(float16 a, float_status *status) +{ + if (!float16_is_any_nan(a)) { + return false; + } + if (no_signaling_nans(status)) { + return false; + } + uint16_t frac =3D float16_val(a) & 0x3FF; + bool frac_msb =3D (frac >> 9) & 1; + return frac_msb =3D=3D snan_bit_is_one(status); +} =20 /*------------------------------------------------------------------------= ---- | Returns 1 if the half-precision floating-point value `a' is a quiet @@ -233,17 +249,27 @@ floatx80 floatx80_default_inf(bool zSign, float_statu= s *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 { + if (!float16_is_any_nan(a_)) { + return false; + } + return !float16_is_snan_internal(a_, status); +} =20 - return ((a >> 9) & 0x3F) =3D=3D 0x3F; - } +/*------------------------------------------------------------------------= ---- +| Internal helper: Determine if bfloat16 NaN is signaling. +*-------------------------------------------------------------------------= ---*/ + +static bool bfloat16_is_snan_internal(bfloat16 a, float_status *status) +{ + if (!bfloat16_is_any_nan(a)) { + return false; + } + if (no_signaling_nans(status)) { + return false; } + uint16_t frac =3D a & 0x7F; + bool frac_msb =3D (frac >> 6) & 1; + return frac_msb =3D=3D snan_bit_is_one(status); } =20 /*------------------------------------------------------------------------= ---- @@ -253,16 +279,10 @@ bool float16_is_quiet_nan(float16 a_, float_status *s= tatus) =20 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; - } + if (!bfloat16_is_any_nan(a_)) { + return false; } + return !bfloat16_is_snan_internal(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -272,16 +292,7 @@ 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_snan_internal(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -291,16 +302,24 @@ bool float16_is_signaling_nan(float16 a_, float_statu= s *status) =20 bool bfloat16_is_signaling_nan(bfloat16 a_, float_status *status) { + return bfloat16_is_snan_internal(a_, status); +} + +/*------------------------------------------------------------------------= ---- +| Internal helper: Determine if float32 NaN is signaling. +*-------------------------------------------------------------------------= ---*/ + +static bool float32_is_snan_internal(float32 a, float_status *status) +{ + if (!float32_is_any_nan(a)) { + return false; + } 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; } + uint32_t frac =3D float32_val(a) & 0x7FFFFF; + bool frac_msb =3D (frac >> 22) & 1; + return frac_msb =3D=3D snan_bit_is_one(status); } =20 /*------------------------------------------------------------------------= ---- @@ -310,16 +329,10 @@ bool bfloat16_is_signaling_nan(bfloat16 a_, float_sta= tus *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); - } + if (!float32_is_any_nan(a_)) { + return false; } + return !float32_is_snan_internal(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -329,16 +342,24 @@ 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_snan_internal(a_, status); +} + +/*------------------------------------------------------------------------= ---- +| Internal helper: Determine if float64 NaN is signaling. +*-------------------------------------------------------------------------= ---*/ + +static bool float64_is_snan_internal(float64 a, float_status *status) +{ + if (!float64_is_any_nan(a)) { + return false; + } 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; } + uint64_t frac =3D float64_val(a) & 0xFFFFFFFFFFFFFULL; + bool frac_msb =3D (frac >> 51) & 1; + return frac_msb =3D=3D snan_bit_is_one(status); } =20 /*------------------------------------------------------------------------= ---- @@ -348,17 +369,10 @@ bool float32_is_signaling_nan(float32 a_, float_statu= s *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); - } + if (!float64_is_any_nan(a_)) { + return false; } + return !float64_is_snan_internal(a_, status); } =20 /*------------------------------------------------------------------------= ---- @@ -368,17 +382,7 @@ 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_snan_internal(a_, status); } =20 /*------------------------------------------------------------------------= ---- --=20 2.52.0