[rtl] Optimization question.

[Oleg Subbotin <oleg@rtlinux.cs.nmt.edu>]

Hello, everybody.
I have this tiny example :

#define ONE 0x01

int fun ()
{
        volatile register temp=0;

        while ( temp&ONE ) {
        /* Do something */
        }
}

And when I compile it with gcc -O2 -S I get this assembly code:

fun:
        pushl %ebp
        movl %esp,%ebp
        subl $4,%esp
        movl $0,-4(%ebp)
        .align 4
.L2:
        movl -4(%ebp),%eax
        testb $1,%al               <--Instead of logical AND gcc generate testb
        jne .L2			   <--But for test==3,5,7... it will not work
        leave			   <--as I expect it to
        ret 

Does anybody knows how to avoid this?
I absolutely have to compile the program with -O2 flag, but with this 
"optimization" my program does not work. I am also very surprized by my
discovery - this type of code is all over the Linux code, but it still
works.

Thanks for any help.

Oleg.

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