Integrated: 8372948: Store end positions directly in JCTree

[Liam Miller-Cushon]

On Tue, 2 Dec 2025 16:05:27 GMT, Liam Miller-Cushon <cushon at openjdk.org> wrote:

> This change adds a field to `JCTree` to store end positions, instead of using a separate `EndPosTable` map. See also [this compiler-dev@ thread](https://mail.openjdk.org/pipermail/compiler-dev/2025-November/032254.html).
> 
> I performed the refactoring in stages, preserving existing semantics at each step.
> 
> There are two known places where this changes existing behaviour that are reflected in changes to tests:
> 
> * `test/langtools/tools/javac/api/TestJavacTask_Lock.java` - this test asserts that calling `JavacTask#parse` first and then calling `#call` or `#parse` second will fail. The assertion that the test is currently expecting is thrown when the `EndPosTable` gets set a second time, and this change means that no longer results in an exception. If desired `JavacTask#parse` could be updated to explicitly check if it is called twice and fail, instead of indirectly relying on the `EndPosTable` for that.
> 
> * `test/langtools/tools/javac/diags/DiagnosticGetEndPosition.java` - there's a comment that 'ideally would be "0", but the positions are not fully set yet', and with the new approach the end position is available to the test, so it resolves the comment. Also the test logic didn't handle platform specific line ending variations correctly, so I updated it to work on windows now that end positions are present.

This pull request has now been integrated.

Changeset: b0829a54
Author:    Liam Miller-Cushon <cushon at openjdk.org>
URL:       https://git.openjdk.org/jdk/commit/b0829a54cd787d5e378573f69ec0b82b40602454
Stats:     583 lines in 32 files changed: 18 ins; 451 del; 114 mod

8372948: Store end positions directly in JCTree

Reviewed-by: jlahoda, mcimadamore

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PR: https://git.openjdk.org/jdk/pull/28610