From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([209.51.188.92]:38765) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1gxHrl-00035y-3m for qemu-devel@nongnu.org; Fri, 22 Feb 2019 15:56:17 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1gxHgu-0006rf-B7 for qemu-devel@nongnu.org; Fri, 22 Feb 2019 15:45:05 -0500 Received: from mail-wr1-x442.google.com ([2a00:1450:4864:20::442]:46007) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1gxHgu-0006q7-0I for qemu-devel@nongnu.org; Fri, 22 Feb 2019 15:45:04 -0500 Received: by mail-wr1-x442.google.com with SMTP id w17so3717702wrn.12 for ; Fri, 22 Feb 2019 12:45:03 -0800 (PST) From: =?UTF-8?q?Alex=20Benn=C3=A9e?= Date: Fri, 22 Feb 2019 20:44:56 +0000 Message-Id: <20190222204500.24434-3-alex.bennee@linaro.org> In-Reply-To: <20190222204500.24434-1-alex.bennee@linaro.org> References: <20190222204500.24434-1-alex.bennee@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: [Qemu-devel] [PATCH v1 2/6] softfloat: add float128_is_{normal, denormal} List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: qemu-s390x@nongnu.org, David Hildenbrand , Richard Henderson , =?UTF-8?q?Alex=20Benn=C3=A9e?= From: David Hildenbrand 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. Signed-off-by: David Hildenbrand Reviewed-by: Richard Henderson Signed-off-by: Alex Bennée --- include/fpu/softfloat.h | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/include/fpu/softfloat.h b/include/fpu/softfloat.h index 38a5e99cf3..3ff5215b81 100644 --- a/include/fpu/softfloat.h +++ b/include/fpu/softfloat.h @@ -466,7 +466,7 @@ 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) @@ -622,7 +622,7 @@ 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) @@ -940,6 +940,16 @@ 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 && -- 2.20.1