From: Damian McGuckin <damianm@esi.com.au>
To: musl@lists.openwall.com
Subject: [musl] Triggering Overflow (or Underflow) without triggering Inexact on i386
Date: Tue, 21 Jan 2020 08:11:50 +1100 (AEDT) [thread overview]
Message-ID: <alpine.LRH.2.02.2001210803250.18026@key0.esi.com.au> (raw)
In-Reply-To: <20200120173804.GM30412@brightrain.aerifal.cx>
I am trying to write arithmetic expressions using only x87 instructions to
trigger an exception. The ASM instruction to raise the flag in the status
register has way too much overhead.
My normal technique of doing either of these would also trigger Inexact.
e.g.
volatile long double t;
Overflow: t = largest normal long double, t *= t;
Underflow: t = smallest normal long double, t *= t;
Can it be triggered WITHOUT also triggering INEXACT?
Regards - Damian
Pacific Engineering Systems International, 277-279 Broadway, Glebe NSW 2037
Ph:+61-2-8571-0847 .. Fx:+61-2-9692-9623 | unsolicited email not wanted here
Views & opinions here are mine and not those of any past or present employer
next prev parent reply other threads:[~2020-01-20 21:12 UTC|newest]
Thread overview: 62+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-01-16 4:30 [musl] Considering x86-64 fenv.s to C Damian McGuckin
2020-01-16 15:11 ` Markus Wichmann
2020-01-16 16:14 ` Rich Felker
2020-01-16 18:56 ` Damian McGuckin
2020-01-16 19:33 ` Rich Felker
2020-01-16 21:31 ` Damian McGuckin
2020-01-17 3:36 ` Damian McGuckin
2020-01-17 3:48 ` Damian McGuckin
2020-01-17 3:53 ` David Edelsohn
2020-01-17 14:13 ` Rich Felker
2020-01-17 14:19 ` David Edelsohn
2020-01-17 14:53 ` Rich Felker
2020-01-18 4:45 ` Damian McGuckin
2020-01-18 5:29 ` Rich Felker
2020-01-19 8:50 ` Damian McGuckin
2020-01-19 9:07 ` Damian McGuckin
2020-01-19 10:42 ` Szabolcs Nagy
2020-01-19 12:25 ` Damian McGuckin
2020-01-20 5:32 ` Damian McGuckin
2020-01-20 17:38 ` Rich Felker
2020-01-20 21:11 ` Damian McGuckin [this message]
2020-01-20 22:32 ` [musl] Triggering Overflow (or Underflow) without triggering Inexact on i386 Szabolcs Nagy
2020-01-21 3:53 ` [musl] Considering x86-64 fenv.s to C Damian McGuckin
2020-01-21 4:22 ` Rich Felker
2020-01-21 4:46 ` Damian McGuckin
2020-01-21 7:26 ` Damian McGuckin
2020-01-17 16:41 ` Markus Wichmann
2020-01-18 1:15 ` Szabolcs Nagy
2020-01-18 5:03 ` Damian McGuckin
2020-01-18 5:37 ` Rich Felker
2020-01-18 9:40 ` Szabolcs Nagy
2020-01-24 0:42 ` Damian McGuckin
2020-01-24 1:11 ` Rich Felker
2020-01-24 4:13 ` Damian McGuckin
2020-01-24 4:55 ` Rich Felker
2020-01-24 6:08 ` Damian McGuckin
2020-01-24 13:44 ` Rich Felker
2020-01-24 14:45 ` Damian McGuckin
2020-01-24 23:59 ` Damian McGuckin
2020-01-25 0:11 ` Rich Felker
2020-01-26 3:28 ` Damian McGuckin
2020-01-26 3:28 ` Damian McGuckin
2020-01-26 3:30 ` Damian McGuckin
2020-01-26 3:32 ` Damian McGuckin
2020-01-26 5:25 ` Damian McGuckin
2020-01-27 3:32 ` Damian McGuckin
2020-01-27 5:39 ` Damian McGuckin
2020-02-02 0:47 ` Damian McGuckin
2020-02-03 0:54 ` Damian McGuckin
2020-02-03 2:09 ` Rich Felker
2020-02-03 2:12 ` Damian McGuckin
2020-02-22 20:17 ` Rich Felker
2020-02-22 20:53 ` Damian McGuckin
2020-02-23 5:41 ` Damian McGuckin
2020-02-23 6:25 ` Rich Felker
2020-02-23 8:35 ` Damian McGuckin
2020-02-07 21:25 ` Damian McGuckin
2020-02-07 21:38 ` Rich Felker
2020-02-07 23:53 ` Damian McGuckin
2020-02-09 5:04 ` Damian McGuckin
2020-01-24 7:10 ` Damian McGuckin
2020-01-18 5:04 ` Markus Wichmann
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