RFR: 8308869: C2: use profile data in subtype checks when profile has more than one class [v7]

[Vladimir Ivanov]

On Tue, 11 Jul 2023 14:08:53 GMT, Roland Westrelin <roland at openjdk.org> wrote:

>> test/hotspot/jtreg/compiler/c2/irTests/ProfileAtTypeCheck.java line 44:
>> 
>>> 42:         flags.add("-XX:TypeProfileSubTypeCheckCommonThreshold=90");
>>> 43:         if (!Platform.is32bit()) {
>>> 44:             flags.add("-XX:-UseCompressedClassPointers");
>> 
>> What's the purpose of `-XX:-UseCompressedClassPointers` on 64-bit platforms? Make it easier to match the IR?
>
> It is to make it easier to match the IR. I could update the rules so it's not required.

I'm fine with it either way.

-------------

PR Review Comment: https://git.openjdk.org/jdk/pull/14375#discussion_r1262796420