From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from zen.linaro.local ([81.128.185.34]) by smtp.gmail.com with ESMTPSA id a34sm3466724wra.64.2017.10.13.09.24.42 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Fri, 13 Oct 2017 09:24:48 -0700 (PDT) Received: from zen.linaroharston (localhost [127.0.0.1]) by zen.linaro.local (Postfix) with ESMTP id 131903E0899; Fri, 13 Oct 2017 17:24:39 +0100 (BST) From: =?UTF-8?q?Alex=20Benn=C3=A9e?= To: richard.henderson@linaro.org Cc: peter.maydell@linaro.org, qemu-devel@nongnu.org, qemu-arm@nongnu.org, =?UTF-8?q?Alex=20Benn=C3=A9e?= , Aurelien Jarno Subject: [RFC PATCH 09/30] softfloat: propagate signalling NaNs in MINMAX Date: Fri, 13 Oct 2017 17:24:17 +0100 Message-Id: <20171013162438.32458-10-alex.bennee@linaro.org> X-Mailer: git-send-email 2.14.1 In-Reply-To: <20171013162438.32458-1-alex.bennee@linaro.org> References: <20171013162438.32458-1-alex.bennee@linaro.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-TUID: eB+6yvsWzafV 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 --- fpu/softfloat.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/fpu/softfloat.c b/fpu/softfloat.c index 013b223947..6ab4b39c09 100644 --- a/fpu/softfloat.c +++ b/fpu/softfloat.c @@ -7684,6 +7684,7 @@ 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. @@ -7704,11 +7705,14 @@ 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)) { \ + 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; \ } \ } \ -- 2.14.1