From: Richard Henderson <richard.henderson@linaro.org>
To: "Alex Bennée" <alex.bennee@linaro.org>, qemu-devel@nongnu.org
Cc: 1841592@bugs.launchpad.net, pc@us.ibm.com
Subject: Re: [Qemu-devel] [PATCH] tests/tcg: add float_madds test to multiarch
Date: Sat, 14 Sep 2019 11:12:13 -0400 [thread overview]
Message-ID: <6ef910fa-d387-faf3-4647-209beaf7886a@linaro.org> (raw)
In-Reply-To: <20190913134935.29696-1-alex.bennee@linaro.org>
On 9/13/19 9:49 AM, Alex Bennée wrote:
> + /* must be built with -O2 to generate fused op */
> + r = a * b + c;
I would prefer to use fmaf() or __builtin_fmaf() here.
Although you'll need to link with -lm just in case the
target doesn't support an instruction for fmaf and so
the builtin expands to the standard library call.
I also like Paul's suggestion to use hex float constants.
r~
next prev parent reply other threads:[~2019-09-14 15:13 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-08-27 13:21 [Qemu-devel] [Bug 1841592] [NEW] ppc: softfloat float implementation issues Paul Clarke
2019-08-27 13:26 ` [Qemu-devel] [Bug 1841592] " Paul Clarke
2019-09-12 17:11 ` Alex Bennée
2019-09-12 18:39 ` Alex Bennée
2019-09-12 19:27 ` Richard Henderson
2019-09-12 21:30 ` Alex Bennée
2019-09-13 8:47 ` Alex Bennée
2019-09-13 13:49 ` [Qemu-devel] [PATCH] tests/tcg: add float_madds test to multiarch Alex Bennée
2019-09-13 13:49 ` [Qemu-devel] [Bug 1841592] " Alex Bennée
2019-09-13 14:50 ` [Qemu-devel] " Paul Clarke
2019-09-13 14:50 ` [Qemu-devel] [Bug 1841592] " Paul Clarke
2019-09-14 15:12 ` Richard Henderson [this message]
2019-09-14 17:59 ` [Qemu-devel] " Alex Bennée
2019-09-14 17:59 ` [Qemu-devel] [Bug 1841592] " Alex Bennée
2019-09-14 18:11 ` [Qemu-devel] " Richard Henderson
2019-09-13 14:13 ` [Qemu-devel] [Bug 1841592] Re: ppc: softfloat float implementation issues Alex Bennée
2019-11-14 4:17 ` Launchpad Bug Tracker
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