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Mail Archives: djgpp-workers/1999/07/02/02:41:31

Sender: bill AT delorie DOT com
Message-ID: <377C5986.1B33420B@taniwha.org>
Date: Fri, 02 Jul 1999 18:17:42 +1200
From: Bill Currie <bill AT taniwha DOT org>
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To: djgpp-workers AT delorie DOT com
Subject: Re: .align directives in libc.a
References: <Pine DOT SUN DOT 3 DOT 91 DOT 990701074005 DOT 22046A-100000 AT is> <377BB217 DOT 2FFBAEA8 AT inti DOT gov DOT ar>
Reply-To: djgpp-workers AT delorie DOT com

salvador wrote:
> Can we tell Gas to use "int 3" (or other trap) when pading between functions?
> (and any other place where the code should never be executed).

so long as it's only for text areas that are never meant to be
executed.  You wouldn't want loop padding to do a debug trap. 'Twould
kinda slow things down:)

> > Intel manuals seem to recommend 16-byte alignment, both for code and
> > for data.
> 
> And that's normally the best. MSVC uses 16 and 32 (based on some strange
> criteria).

Isn't 32 bytes the size of a cache line on 486+?

> But looks like the most sensitive stuff is the entry point of functions, not the
> align of loops or jumps.

Nope, any destination: functions, loops and jumps are all equally
important.

Bill
-- 
Leave others their otherness.

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