RFR: 8257726: Make -XX:+StressLdcRewrite option a diagnostic option

[Thomas Stuefe]

On Tue, 15 Dec 2020 17:26:25 GMT, Coleen Phillimore <coleenp at openjdk.org> wrote:

> See bug for details.  Tested:
> 
> $ java -XX:+StressLdcRewrite -version
> Error: VM option 'StressLdcRewrite' is diagnostic and must be enabled via -XX:+UnlockDiagnosticVMOptions.
> Error: The unlock option must precede 'StressLdcRewrite'.
> Error: Could not create the Java Virtual Machine.
> Error: A fatal exception has occurred. Program will exit.
> $ java -XX:+UnlockDiagnosticVMOptions -XX:+StressLdcRewrite -version
> openjdk version "16-internal" 2021-03-16
> OpenJDK Runtime Environment (build 16-internal+0-2020-12-15-1356558.coleen...)
> OpenJDK 64-Bit Server VM (build 16-internal+0-2020-12-15-1356558.coleen..., mixed mode, sharing)
> 
> Also, java/lang/instrument which has a test using StressLdcRewrite and tier1.

Looks right to me, and trivial. This should not be a product option.
I cannot believe anyone uses this option in earnest in production. Still, out of sheer fascination I googled but did not find any serious usage.

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Marked as reviewed by stuefe (Reviewer).

PR: https://git.openjdk.java.net/jdk/pull/1783