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Re: Combine four insns
On 08/10/2010 04:39 PM, Richard Guenther wrote:
> You could enable the heuristic with optimize < 3 && !optimize_size
> (thus keep combining everything at -O3 and -Os).
I could do that. I just need to know what the consensus opinion is.
> Did you try just using the ncst == 0 heuristic?
Yes. That left so many instances of opportunities like
- lsl r3, r1, #31
- lsr r3, r3, #31
- lsl r3, r3, #24
- lsr r3, r3, #24
+ mov r3, #1
+ and r3, r1
that I thought it better to add a special case.
Bernd