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Re: Loop unrolling
- To: amylaar at cygnus dot co dot uk
- Subject: Re: Loop unrolling
- From: Martin von Loewis <martin at mira dot isdn dot cs dot tu-berlin dot de>
- Date: Wed, 3 Jun 1998 23:03:13 +0200
- CC: egcs at cygnus dot com
- References: <199806022059.VAA16755@phal.cygnus.co.uk>
> i has automatic storage, and its address is never taken, so the compiler
> might decide to allocate this object to some 'write-only-memory'.
No, it may not. Modification of i is 'observable behaviour' as per
[intro.execution]/6. So I want to observe this on the machine in front
of me. If the compiler optimizes the loop away, I cannot observe it.
If it would leave the loop, I could observe it, eg. by means of a
debugger.
Regards,
Martin