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From: Jim Wilson <wilson@cygnus.com>
To: law@cygnus.com
Cc: Kamil Iskra <kamil@dwd.interkom.pl>, egcs@cygnus.com
Subject: Re: Loop optimizer misses simple optimisation?
Date: Sun, 03 May 1998 15:32:00 -0000	[thread overview]
Message-ID: <199805032232.PAA08246@rtl.cygnus.com> (raw)
In-Reply-To: <19466.894225692@hurl.cygnus.com>

	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.

Jim

  reply	other threads:[~1998-05-03 15:32 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 [this message]
1998-05-03 20:10         ` Jeffrey A Law
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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