RFR(L) Take 2 of Valhalla support for AArch64

[Ioi Lam]

Hi Dmitry,

The C1 changes look OK to me. I guess they are like 80% similar to the 
x64 code. I wish we had better organization in the C1 code so we can 
avoid the duplication :-(

BTW, (you may know this already) to validate C1 changes, you can do this:

         cd test/hotspot/jtreg/compiler/valhalla/valuetypes
         jtreg -Dtest.c1=true \
             -vmoptions:-XX:+EnableValhallaC1 \
             -vmoptions:-XX:TieredStopAtLevel=1 \
             -vmoptions:-XX:-ValueTypePassFieldsAsArgs \
             -vmoptions:-XX:-ValueTypeReturnedAsFields \
             .

Currently all the tests passed on x64 in this mode.

Thanks
- Ioi


On 3/27/19 8:14 AM, Dmitry Samersoff wrote:
> Hello Everybody,
>
> Please, review the next version of the changes against lworld branch:
>
> http://cr.openjdk.java.net/~dsamersoff/valhalla_lworld_aarch64/webrev.04
>
> *What is done:*
>
> *  Shared interface changes are adopted.
>
> *  24 tests of 24 from runtime/valhalla/valuetypes are passed.
>
> *   11 of 14 tests from compiler/valhalla/valuetypes are passed with
> ValueTypePassFieldsAsArgs=Off, ValueTypeReturnedAsFields=Off
>
> *  Support for ValueTypePassFieldsAsArgs and ValueTypeReturnedAsFields
> is implemented, but not complete.
>
>
> *Open points:*
>
> 1. Tests:
>
>    compiler/valhalla/valuetypes/TestMethodHandles.java
>    compiler/valhalla/valuetypes/TestBasicFunctionality.java (partially)
>
>    Fails because the count of ALLOC doesn't match to the count expected
> by the test. I'm looking into it.
>
>
> 2. Support for ValueTypePassFieldsAsArgs and ValueTypeReturnedAsFields
> is implemented but there are some issues
>
>    I'll send a separate letter about it. I'll be happy if someone with
> good C2 knowledge chimes in with thoughts on it
>
>    Temporary, I forced these flags to OFF for AArch64
>
>
> 3. One test still fails
>
>     compiler/valhalla/valuetypes/TestNewAcmp.java (one test within it)
>
>     Fails with:
>     Test failed: should return false
>
>
> 4. JNI tests doesn't run.
>
>     Plan to address it on the next turn.
>
>
> Regards,
> -Dmitry
>
>