On Wed, May 30, 2018 at 04:14:02PM +0800, Simon Guo wrote:

Hi Segher,
On Mon, May 28, 2018 at 06:05:59AM -0500, Segher Boessenkool wrote:

quoted

On Fri, May 25, 2018 at 12:07:34PM +0800, wei.guo.simon@gmail.com wrote:

quoted

+	/* save and restore cr0 */
+	mfocrf  r5,64
+	EXIT_VMX_OPS
+	mtocrf	64,r5
+	b	.LcmpAB_lightweight

That's cr1, not cr0.  You can use mcrf instead, it is cheaper (esp. if
you have it in a non-volatile CR field before so you need only one, if any).

You are right :) How about using mtcr/mfcr instead, I think they are
fast as well and more readable.

Those are much worse than m[ft]ocrf.

You probably should just shuffle things around so that EXIT_VMX_OPS
does not clobber the CR field you need to keep.


Segher