From: Jeffrey A Law <law@cygnus.com>
To: "Andrew Davies" <Andrew_Davies@Xmitel.com>
Cc: help-gcc@gnu.org
Subject: Re: Over optimisation
Date: Thu, 30 Sep 1999 23:56:00 -0000 [thread overview]
Message-ID: <11660.938097626@upchuck.cygnus.com> (raw)
Message-ID: <19990930235600.IXPFrGN0JO10J0ND0OKbvnjopTfYLCqEBFJBTmkZtZs@z> (raw)
In-Reply-To: <01bf05ce$5ca544c0$4f7fa890@us1.lincoln.msl.mitel.com>
In message < 01bf05ce$5ca544c0$4f7fa890@us1.lincoln.msl.mitel.com >you write:
> Hi,
> I have a problem with the optimiser. When I compile the following test
> loop:
>
> do {
> test = regbase->utx & 0x8000;
> }while(test == 0x0000);
>
>
> It produces the following code:
>
>
> send_byte:
> link.w %a6,#0
> move.w 16775430,%d0
> and.w #32768,%d0
> .even
> .L9:
> tst.w %d0
> jbeq .L9
>
> I think the optimiser is assuming the line inside the do while loop is
> static and therefore removes it from the loop. As a result it gets stuck.
> Anyone know how to solve this without turning the optimiser off?
There's no way to tell without a complete bug report. Please read the FAQ to
learn how to properly send bug reports.
jeff
next prev parent reply other threads:[~1999-09-30 23:56 UTC|newest]
Thread overview: 11+ messages / expand[flat|nested] mbox.gz Atom feed top
1999-09-23 7:26 Andrew Davies
1999-09-23 7:43 ` Jeffrey A Law [this message]
1999-09-30 23:56 ` Jeffrey A Law
1999-10-01 0:00 ` Jeffrey A Law
1999-09-23 8:13 ` Michel Decima
1999-09-30 23:56 ` Michel Decima
1999-10-01 0:00 ` Michel Decima
1999-09-30 23:56 ` Andrew Davies
1999-10-01 0:00 ` Andrew Davies
1999-10-03 9:55 ` Veksler Michael
1999-10-31 13:57 ` Veksler Michael
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