[aarch64-port-dev ] RFR: JDK-8203041 : AArch64: fix overflow in immediate cmp/cmn instruction

[Andrew Haley]

On 05/22/2018 08:49 AM, Joshua Zhu wrote:
> I submit http://cr.openjdk.java.net/~zyao/8203041/webrev.02/ for review.
> I think there will be another change to cover all rscratch alias issue mentioned by Andrew. Therefore I do not touch it.

Thanks very much.  Please add this comment before the first subs.
No need for another review.

  // tmp6 is not used.  MacroAssembler::subs is used here (rather than
  // cmp) because subs allows an unlimited range of immediate operand.

I had a look at using some C++ features to detect automagically when
cmp is being used with a variable as its immediate operand, but it's
very difficult to do.

-- 
Andrew Haley
Java Platform Lead Engineer
Red Hat UK Ltd. <https://www.redhat.com>
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