RFR (M): 8220301: Remove jbyte use in CardTable (affects all platforms)

[Thomas Schatzl]

Hi,

On Fri, 2019-03-08 at 17:58 +0100, Aleksey Shipilev wrote:
> On 3/8/19 2:51 PM, Thomas Schatzl wrote:
> > While the change itself is a no-op in practice, and testing showed
> > so,
> > I would like non-Oracle platform maintainers to try to compile the
> > change and report problems because of lack of build platforms.
> > 
> > CR:
> > https://bugs.openjdk.java.net/browse/JDK-8220301
> > Webrev:
> > http://cr.openjdk.java.net/~tschatzl/8220301/webrev/
> 
> Not sure why do we need to drag CardTable::CardValue all over the
> place, and then STATIC_ASSERT its
> size, when we could "just" do uint8_t everywhere?

There has been some short internal discussion that preferred a typedef
instead of uint8_t right away. I am somewhat preferring the typedef at
this point (working in loosely related JDK-8213108) but I am good with
a straight uint8_t too. Let's see what others think.

The STATIC_ASSERTs are imo better replacements for the existing asserts
that do the same as they fail on compile and not during runtime.

> 
> Anyway, these configs build fine:
>   linux-aarch64-server-fastdebug
>   linux-arm-server-fastdebug
>   linux-s390x-server-fastdebug
>   linux-x86-server-fastdebug
>   linux-x86_64-minimal-fastdebug
>   linux-x86_64-zero-fastdebug
> 
> And linux-ppc64le-server-fastdebug fails with:
[...]
> It passes with this addendum:
> 

Thanks for getting them through these platforms, fixed in
http://cr.openjdk.java.net/~tschatzl/8220301/webrev.0_to_1/ (diff)
http://cr.openjdk.java.net/~tschatzl/8220301/webrev.1/ (full)

Thanks,
  Thomas