From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:51445) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eYsvp-0006ed-8C for qemu-devel@nongnu.org; Tue, 09 Jan 2018 07:23:11 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eYsvn-0006d8-Ow for qemu-devel@nongnu.org; Tue, 09 Jan 2018 07:23:05 -0500 Received: from mail-wr0-x241.google.com ([2a00:1450:400c:c0c::241]:44851) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1eYsvn-0006aT-Hf for qemu-devel@nongnu.org; Tue, 09 Jan 2018 07:23:03 -0500 Received: by mail-wr0-x241.google.com with SMTP id w50so4697081wrc.11 for ; Tue, 09 Jan 2018 04:23:03 -0800 (PST) From: =?UTF-8?q?Alex=20Benn=C3=A9e?= Date: Tue, 9 Jan 2018 12:22:39 +0000 Message-Id: <20180109122252.17670-8-alex.bennee@linaro.org> In-Reply-To: <20180109122252.17670-1-alex.bennee@linaro.org> References: <20180109122252.17670-1-alex.bennee@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: [Qemu-devel] [PATCH v2 07/20] fpu/softfloat: propagate signalling NaNs in MINMAX List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: richard.henderson@linaro.org, peter.maydell@linaro.org, laurent@vivier.eu, bharata@linux.vnet.ibm.com, andrew@andrewdutcher.com Cc: qemu-devel@nongnu.org, =?UTF-8?q?Alex=20Benn=C3=A9e?= , Aurelien Jarno While a comparison between a QNaN and a number will return the number it is not the same with a signaling NaN. In this case the SNaN will "win" and after potentially raising an exception it will be quietened. Signed-off-by: Alex Bennée Reviewed-by: Richard Henderson --- v2 - added return for propageFloat --- fpu/softfloat.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 3a4ab1355f..44c043924e 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -7683,6 +7683,7 @@ int float128_compare_quiet(float128 a, float128 b, float_status *status) * minnum() and maxnum() functions. These are similar to the min() * and max() functions but if one of the arguments is a QNaN and * the other is numerical then the numerical argument is returned. + * SNaNs will get quietened before being returned. * minnum() and maxnum correspond to the IEEE 754-2008 minNum() * and maxNum() operations. min() and max() are the typical min/max * semantics provided by many CPUs which predate that specification. @@ -7703,11 +7704,14 @@ static inline float ## s float ## s ## _minmax(float ## s a, float ## s b, \ if (float ## s ## _is_any_nan(a) || \ float ## s ## _is_any_nan(b)) { \ if (isieee) { \ - if (float ## s ## _is_quiet_nan(a, status) && \ + if (float ## s ## _is_signaling_nan(a, status) || \ + float ## s ## _is_signaling_nan(b, status)) { \ + return propagateFloat ## s ## NaN(a, b, status); \ + } else if (float ## s ## _is_quiet_nan(a, status) && \ !float ## s ##_is_any_nan(b)) { \ return b; \ } else if (float ## s ## _is_quiet_nan(b, status) && \ - !float ## s ## _is_any_nan(a)) { \ + !float ## s ## _is_any_nan(a)) { \ return a; \ } \ } \ -- 2.15.1