From 24a2bd702c0029ac878979a2857bd7dccce74d32 Mon Sep 17 00:00:00 2001 From: David Hildenbrand Date: Thu, 28 Feb 2019 15:11:39 -0500 Subject: [PATCH] softfloat: add float128_is_{normal,denormal} Needed on s390x, to test for the data class of a number. So it will gain soon a user. A number is considered normal if the exponent is neither 0 nor all 1's. That can be checked by adding 1 to the exponent, and comparing against >= 2 after dropping an eventual overflow into the sign bit. While at it, convert the other floatXX_is_normal functions to use a similar, less error prone calculation, as suggested by Richard H. Backports commit 47393181604d507f4fe2a15a65b1eede0f974d6a from qemu --- qemu/include/fpu/softfloat.h | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/qemu/include/fpu/softfloat.h b/qemu/include/fpu/softfloat.h index 457247e2..665b7288 100644 --- a/qemu/include/fpu/softfloat.h +++ b/qemu/include/fpu/softfloat.h @@ -471,7 +471,7 @@ static inline int float32_is_zero_or_denormal(float32 a) static inline bool float32_is_normal(float32 a) { - return ((float32_val(a) + 0x00800000) & 0x7fffffff) >= 0x01000000; + return (((float32_val(a) >> 23) + 1) & 0xff) >= 2; } static inline bool float32_is_denormal(float32 a) @@ -628,7 +628,7 @@ static inline int float64_is_zero_or_denormal(float64 a) static inline bool float64_is_normal(float64 a) { - return ((float64_val(a) + (1ULL << 52)) & -1ULL >> 1) >= 1ULL << 53; + return (((float64_val(a) >> 52) + 1) & 0x7ff) >= 2; } static inline bool float64_is_denormal(float64 a) @@ -948,6 +948,16 @@ static inline int float128_is_zero_or_denormal(float128 a) return (a.high & 0x7fff000000000000LL) == 0; } +static inline bool float128_is_normal(float128 a) +{ + return (((a.high >> 48) + 1) & 0x7fff) >= 2; +} + +static inline bool float128_is_denormal(float128 a) +{ + return float128_is_zero_or_denormal(a) && !float128_is_zero(a); +} + static inline int float128_is_any_nan(float128 a) { return ((a.high >> 48) & 0x7fff) == 0x7fff &&