From mboxrd@z Thu Jan  1 00:00:00 1970
From: "Andrew Davies" <Andrew_Davies@Xmitel.com>
To: help-gcc@gnu.org
Subject: Over optimisation
Date: Fri, 01 Oct 1999 00:00:00 -0000
Message-ID: <01bf05ce$5ca544c0$4f7fa890@us1.lincoln.msl.mitel.com>
X-SW-Source: 1999-q3/msg00764.html
Message-ID: <19991001000000.I1OO9e0wH0jY7yB5zsqmbbk3puJrS751MHLbNVUDj5o@z>

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? 

Thanks