[foreign] RFR 8216484: jextract LayoutUtils has to be modified for Windows

[Sundararajan Athijegannathan]

jextract supports ToolProvider interface. It is possible to create 
multiple instances of jextract in the same process. LayoutUtils has  a 
static cache which is initialized using sizes obtained from clang 
library. In theory it is possible that we may get different sizes for 
types depending on preprocessor settings, 32/64 bit app etc. I think it 
is better if we associate this cache with the current Context instance.

-Sundar

On 12/01/19, 6:58 PM, Jorn Vernee wrote:
> Hi,
>
> Continuing from [1, 2]
>
> I have polished the previous patch a little.
>
> Instead of doing the minimum needed for Windows support I've replaced 
> all the LayoutUtils.Types constants, and instead am querying the type 
> size from libclang and then caching the result, since libclang seems 
> to know the right size to use for the platform.
>
> I have been looking at the libclang API and there doesn't seem to be a 
> way to specify the target platform. I think it always uses the ABI of 
> the platform it was built for.
>
> Bug: https://bugs.openjdk.java.net/browse/JDK-8216484
> Updated Webrev: 
> http://cr.openjdk.java.net/~jvernee/panama/webrevs/windows_jextract/webrev.01/
>
> Cheers,
> Jorn
>
> [1] : 
> https://mail.openjdk.java.net/pipermail/panama-dev/2019-January/003680.html
> [2] : 
> https://mail.openjdk.java.net/pipermail/panama-dev/2019-January/003683.html