[lworld] RFR: 8370195: [lworld] Constant-fold _layout_kind loads from constant FlatArrayKlass

[Tobias Hartmann]

On Sun, 19 Oct 2025 17:13:18 GMT, Quan Anh Mai <qamai at openjdk.org> wrote:

> Hi,
> 
> The load to FlatArrayKlass::_layout_kind can be constant-folded if the receiver is a constant. This eliminates all checks when the array type is known statically or speculated correctly.
> 
> Please leave your reviews, thanks a lot.

Looks good to me. Thanks for fixing!

test/hotspot/jtreg/compiler/valhalla/inlinetypes/TestArrays.java line 3778:

> 3776: 
> 3777:     @Test
> 3778:     @IR(applyIf = {"UseArrayLoadStoreProfile", "true"},

Maybe add a small comment here explaining what the test / IR rule is supposed to catch.

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Marked as reviewed by thartmann (Committer).

PR Review: https://git.openjdk.org/valhalla/pull/1687#pullrequestreview-3355379438
PR Review Comment: https://git.openjdk.org/valhalla/pull/1687#discussion_r2444098599