Integrated: 8330386: Replace Opaque4Node of Initialized Assertion Predicate with new OpaqueInitializedAssertionPredicateNode

[Christian Hagedorn]

On Thu, 25 Apr 2024 13:34:31 GMT, Christian Hagedorn <chagedorn at openjdk.org> wrote:

> This patch replaces the `Opaque4Node` of the `If` for Initialized Assertion Predicates with a new `OpaqueInitializedAsseritonPredicateNode`. This helps to simplify pattern matching for predicate code and to distinguish from the two other uses of `Opaque4` nodes:
> 1. Template Assertion Predicate: The goal is to get rid of its `Opaque4Node` as well by using a dedicated `TemplateAssertionPredicateNode` for the `IfNode`.
> 2. Non-null-checks with instrinsics and unsafe accesses: This will eventually be the only use left. Once we get there, we should rename the node accordingly to `OpaqueNonNullCheck` or something like that.
> 
> I went through all the uses of `Opaque4` nodes and did the following:
> - Could the `Opaque4` node be part of an Initialized Assertion Predicate?
>   - No: Added an assert that we are not dealing with an Initialized Assertion Predicate.
>   - Yes:
>     - Yes **and only** for Initialized Assertion Predicates? Added an assert that we are only expecting an `OpaqueInitializedAsseritonPredicateNode` if appropriate.
>     - Yes but could also be something else: Added case for `OpaqueInitializedAsseritonPredicateNode` next to the `Opaque4` case.
> - Is this `Opaque4` node only used for Template Assertion Predicates?
>   - Yes: Added assert with call to `assertion_predicate_has_loop_opaque_node()` to check that we find its `OpaqueLoop*Nodes`.
>  - I've added test cases where I was not sure about whether an `Opaque4` node could be part of a Template, an Initialized Assertion Predicate or a non-null-check. This was a little tricky but I think it was still worth to prevent future bugs (even though most of these special cases are quite rare).
> 
> This is another patch split off from the full fix for Assertion Predicates.
> 
> Thanks,
> Christian

This pull request has now been integrated.

Changeset: 2edb6d98
Author:    Christian Hagedorn <chagedorn at openjdk.org>
URL:       https://git.openjdk.org/jdk/commit/2edb6d98133d8bd6dc4527c7497c460283fdc53e
Stats:     550 lines in 15 files changed: 483 ins; 8 del; 59 mod

8330386: Replace Opaque4Node of Initialized Assertion Predicate with new OpaqueInitializedAssertionPredicateNode

Reviewed-by: kvn, roland

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PR: https://git.openjdk.org/jdk/pull/18951