From: Jeffrey A Law <law@cygnus.com>
To: Jim Wilson <wilson@cygnus.com>
Cc: Kamil Iskra <kamil@dwd.interkom.pl>, egcs@cygnus.com
Subject: Re: Loop optimizer misses simple optimisation?
Date: Sun, 03 May 1998 20:10:00 -0000 [thread overview]
Message-ID: <23546.894251423@hurl.cygnus.com> (raw)
In-Reply-To: <199805032232.PAA08246@rtl.cygnus.com>
In message < 199805032232.PAA08246@rtl.cygnus.com >you write:
> However, a div or mod operation can not generally be moved out of
> a loop unless you know it won't trap (divide by zero).
>
> If an instruction might trap, then it will be moved out of a loop if we
> can prove that it will be executed at least once.
Ah, yes, you're right. I forgot about that tidbit.
jeff
next prev parent reply other threads:[~1998-05-03 20:10 UTC|newest]
Thread overview: 14+ messages / expand[flat|nested] mbox.gz Atom feed top
1998-04-28 7:23 Kamil Iskra
1998-04-28 19:14 ` Richard Henderson
1998-04-29 14:48 ` PÃ¥l-Kristian Engstad
1998-04-29 16:08 ` Richard Henderson
1998-04-28 19:49 ` Michael Meissner
1998-04-29 15:21 ` Jim Wilson
1998-05-02 6:13 ` Kamil Iskra
1998-05-03 14:15 ` Jeffrey A Law
1998-05-03 15:32 ` Jim Wilson
1998-05-03 20:10 ` Jeffrey A Law [this message]
1998-05-06 7:42 ` Was: " John Vickers
1998-05-06 9:19 ` Jeffrey A Law
1998-05-06 11:36 ` Joern Rennecke
1998-05-07 5:15 ` John Vickers
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