From: Richard Zidlicky <rz@linux-m68k.org>
To: Kevin Lawton <kevinlawton2001@yahoo.com>
Cc: gcc@gcc.gnu.org
Subject: Re: Request of new __attribute__ for switch statements (elimination of the bounds check)
Date: Mon, 14 Oct 2002 08:31:00 -0000 [thread overview]
Message-ID: <20021013235837.A657@linux-m68k.org> (raw)
In-Reply-To: <20021011190521.57024.qmail@web80309.mail.yahoo.com>; from kevinlawton2001@yahoo.com on Fri, Oct 11, 2002 at 12:05:21PM -0700
On Fri, Oct 11, 2002 at 12:05:21PM -0700, Kevin Lawton wrote:
> All,
>
> For implementation of machine simulators, it's quite common
> to have completely populated switch statements on byte values:
>
> unsigned char byte;
>
> switch (byte) {
> case 0:
> case 1:
> ...
> case 255:
> }
>
> But I don't know of any way to tell the compiler to _not_ generate
> a bounds check on the switch variable 'byte'. All of the target
> space is covered.
did you look into using gcc's computed goto?
Richard
next prev parent reply other threads:[~2002-10-14 12:44 UTC|newest]
Thread overview: 32+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-10-11 13:20 Kevin Lawton
2002-10-12 4:18 ` Ralph Loader
2002-10-14 8:31 ` Richard Zidlicky [this message]
2002-10-14 10:09 ` Dale Johannesen
2002-10-14 21:11 ` Jamie Lokier
2002-10-14 22:01 ` Zack Weinberg
2002-10-15 8:12 ` Michael Matz
2002-10-15 19:15 ` Zack Weinberg
2002-10-15 19:18 ` Dale Johannesen
2002-10-16 14:07 ` Richard Henderson
2002-10-15 21:16 ` Kevin Lawton
2002-10-15 23:40 ` Tim Hollebeek
2002-10-16 3:40 ` Michael Matz
2002-10-16 13:38 ` Tim Hollebeek
2002-10-16 14:23 ` Michael Matz
2002-10-16 13:27 ` Hartmut Schirmer
2002-10-16 3:25 ` Joseph S. Myers
2002-10-16 7:57 ` Fergus Henderson
2002-10-16 11:19 ` Daniel Jacobowitz
2002-10-15 7:54 ` Michael Matz
2002-10-15 13:29 ` Jamie Lokier
2002-10-15 14:06 ` Kevin Lawton
2002-10-15 15:32 ` Jamie Lokier
2002-10-15 14:28 ` Michael Matz
2002-10-15 15:19 ` Jamie Lokier
2002-10-11 13:22 Robert Dewar
2002-10-11 15:12 ` Kevin Lawton
2002-10-12 10:43 ` Alexandre Oliva
2002-10-15 6:43 Mattias Engdegård
2002-10-15 22:40 Robert Dewar
2002-10-15 23:57 ` Zack Weinberg
2002-10-16 9:19 Robert Dewar
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