From: Richard Henderson <richard.henderson@linaro.org>
To: Song Gao <gaosong@loongson.cn>, qemu-devel@nongnu.org
Cc: yangxiaojuan@loongson.cn, huqi@loongson.cn,
peter.maydell@linaro.org, alex.bennee@linaro.org,
maobibo@loongson.cn
Subject: Re: [PATCH v2 4/4] target/loongarch: flogb_{s/d} add set float_flag_divbyzero
Date: Wed, 28 Sep 2022 08:24:44 -0700 [thread overview]
Message-ID: <673a8e64-31f4-99a6-2e1d-ffb833237e16@linaro.org> (raw)
In-Reply-To: <20220927064838.3570928-5-gaosong@loongson.cn>
On 9/26/22 23:48, Song Gao wrote:
> if fj ==0 or fj == INT32_MIN/INT64_MIN, LoongArch host set fcsr cause exception FP_DIV0,
> So we need set exception flags float_flagdivbyzero if fj ==0.
You are correct that ieee754 says that logB(0) should raise divbyzero.
This should be fixed in softfloat-parts.c.inc, not here, within
case float_class_zero:
/* log2(0) = -inf */
a->cls = float_class_inf;
a->sign = 1;
return;
r~
next prev parent reply other threads:[~2022-09-28 15:30 UTC|newest]
Thread overview: 13+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-09-27 6:48 [PATCH v2 0/4] Fix some loongarch tcg bugs Song Gao
2022-09-27 6:48 ` [PATCH v2 1/4] target/loongarch: ftint_xxx insns set the result high 32bit 0xffffffff Song Gao
2022-09-28 15:14 ` Richard Henderson
2022-09-29 3:24 ` gaosong
2022-09-27 6:48 ` [PATCH v2 2/4] target/loongarch: bstrins.w need set dest register EXT_SIGN Song Gao
2022-09-28 15:13 ` Richard Henderson
2022-09-29 7:27 ` gaosong
2022-09-29 15:14 ` Richard Henderson
2022-09-27 6:48 ` [PATCH v2 3/4] target/loongarch: Fix fnm{sub/add}_{s/d} set wrong flags Song Gao
2022-09-28 15:16 ` Richard Henderson
2022-09-27 6:48 ` [PATCH v2 4/4] target/loongarch: flogb_{s/d} add set float_flag_divbyzero Song Gao
2022-09-28 15:24 ` Richard Henderson [this message]
2022-09-29 7:27 ` gaosong
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=673a8e64-31f4-99a6-2e1d-ffb833237e16@linaro.org \
--to=richard.henderson@linaro.org \
--cc=alex.bennee@linaro.org \
--cc=gaosong@loongson.cn \
--cc=huqi@loongson.cn \
--cc=maobibo@loongson.cn \
--cc=peter.maydell@linaro.org \
--cc=qemu-devel@nongnu.org \
--cc=yangxiaojuan@loongson.cn \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).