RFR(M): 8223051: support loops with long (64b) trip counts

[John Rose]

On Jun 3, 2020, at 2:16 AM, Roland Westrelin <rwestrel at redhat.com> wrote:
> 
>> loopnode.cpp:
>> - line 504: "check_stride_overflow" is already in 8244504
> 
> Right but the one in this webrev is for longs so doesn't have the same
> signature.

It’s one of those very rare cases where copy/paste/edit is the
right thing to do.  A template or macro would also work, but
that would be overkill, I think.  The way to stay sane here
is to keep the two copies right next to each other, so it’s
blindingly obvious that they have to be maintained together.