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Re: doloop.c fix for PR 6984

On Tue, Jun 18, 2002 at 09:02:00PM +0930, Alan Modra wrote:
> -      /* abs (final - initial) / (abs_inc * unroll_number)  */
> -	  /* abs (final - initial) % (abs_inc * unroll_number)  */
> -	  /* If (abs (final - initial) % (abs_inc * unroll_number)
> -	       <= abs_inc * (unroll - 1)),
> -	     jump past following increment instruction.  */
> +   /* (abs (final - initial) + abs_inc - 1) / (abs_inc * unroll_number)  */

Are you absolutely certain that the original form of this
expression was not done to avoid overflow in edge conditions?
It sure looks like it.


r~
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