RFR: 8374828: Save load_barrier_on_oop_field_preloaded in aot CodeCache

[Andrew Dinn]

On Mon, 12 Jan 2026 22:47:04 GMT, Erik Österlund <eosterlund at openjdk.org> wrote:

> What I care more about is the AOT cache shipped with the JDK, which does not embed any compiled code. It's important that these archives are offered for all GCs, despite not knowing which GC will be selected. Is that still the case?

I believe (and @iklam is the one who can confirm) that the JDK, both in the jdk26 release and in the mainline dev tree, still ships with a default static CDS archive rather than an AOT archive (well, rather two i.e. a coops and non-coops CDS archive).

If and when we do switch to shipping with a default AOT archive we will need to ensure that said archive is GC-neutral, the simple option as far as GC barrier support is concerned being to ensure that the archive does not contain any (generated method or stub) code n.b. that option is available by disabling generation of an embedded code cache when creating the default archive.

We also still need to finesse the choice of coops/non-coops as the layout of the archive heap section depends on the setting at assembly time and the same setting may be unavailable at runtime (if, say, we build with coops and then a very large heap max is specified). We want users to be able to benefit from using a default archive whatever heap size they specify on the command line without also having to force them to use non-coops.

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PR Comment: https://git.openjdk.org/jdk/pull/29129#issuecomment-3743843749