Garbage Collector Code Artifacts: Card Marking

In the JVM, lots of evidence of garbage collection mechanics can be seen from JIT compiler output. This may be obvious if you think of garbage collection as a task of book-keeping: the various auxiliary data structures used to track inter-region or inter-generational references, relied on for faster marking, need to be kept up to
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Floating Point: Manual Unrolling or Autovectorisation?

Java is very strict about floating point arithmetic. There’s even a keyword, strictfp, which allows you to make it stricter, ensuring you’ll get a potentially less precise but identical result wherever you run your program. There’s actually a JEP to make this the only behaviour. JLS 15.18.2 states clearly that floating point addition is not
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