On 2017-11-06 4:27 PM, Helge Deller wrote:
/* Check the validity of the size pointer */
- subi,>>= 4, %r23, %r0
- b,n lws_exit_nosys
+ cmpib,COND(<<),n 3, %r23, lws_exit_nosys
I don't believe that we want to use COND here (i.e., we want a 32-bit
check). We might not
need to trim the upper 32-bits r23.
The reason the code uses nullification is the fast path occurs when the
"b,n" is nullified. So we
avoid the branch prediction penalty. I'd have to check whether the fast
path with the cmpib instruction
is the taken branch or not.
Have no object to changing "4" to "3" instead of changing the condition.
Dave
--
John David Anglin dave.anglin@xxxxxxxx
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