RFR: 8355798: Implement JEP 514: Ahead-of-Time Command Line Ergonomics [v3]

[Vladimir Kozlov]

On Mon, 5 May 2025 01:00:31 GMT, Ioi Lam <iklam at openjdk.org> wrote:

>> This is the implementation of the draft [JEP: Ahead-of-time Command Line Ergonomics](https://bugs.openjdk.org/browse/JDK-8350022)
>> 
>> - Implemented new flag `AOTCacheOutput`, which can be used to create an AOT cache using the "one-command workflow"
>> - Added processing of the `JAVA_AOT_OPTIONS` environment variable that can supply extra VM options when creating an AOT cache
>> - Added `%p` substitution for `AOTCache`, `AOTCacheOutput`, and `AOTConfiguration` options
>> 
>> Please see the [JEP](https://bugs.openjdk.org/browse/JDK-8350022) and [CSR](https://bugs.openjdk.org/browse/JDK-8356010) for detailed specification.
>> 
>> Examples:
>> 
>> 
>> # Create an AOT cache with a single command:
>> $ java -cp HelloWorld.jar -XX:AOTMode=record -XX:AOTCacheOutput=foo.aot HelloWorld
>> Hello World
>> Temporary AOTConfiguration recorded: foo.aot.config
>> Launching child process /usr/bin/java to assemble AOT cache foo.aot using configuration foo.aot.config
>> Picked up JAVA_TOOL_OPTIONS: -Djava.class.path=HelloWorld.jar -XX:AOTCacheOutput=foo.aot -XX:AOTConfiguration=foo.aot.config -XX:AOTMode=create
>> Reading AOTConfiguration foo.aot.config and writing AOTCache foo.aot
>> AOTCache creation is complete: foo.aot 10240000 bytes
>> 
>> # Create logging file for the AOT cache assembly phase
>> $ export AOT_TOOL_COMMAND=-Xlog:cds:file=log.txt
>> $ java -cp HelloWorld.jar -XX:AOTMode=record -XX:AOTCacheOutput=foo.aot HelloWorld
>> 
>> 
>> Note: the child process is launched with Java API because the HotSpot native APIs are not sufficient (no way to set env vars for child process).
>
> Ioi Lam has updated the pull request incrementally with one additional commit since the last revision:
> 
>   @vnkozlov comments

src/hotspot/share/cds/cdsConfig.cpp line 412:

> 410:     log_debug(aot,codecache,init)("AOTCache is not specified - AOTAdapterCaching is ignored");
> 411:   }
> 412: 

Also from merge?

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

PR Review Comment: https://git.openjdk.org/jdk/pull/24942#discussion_r2073760775