More elegant holders for local lazy vals. #5374
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LGTM! |
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LGTM |
viktorklang
reviewed
Mar 15, 2017
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| class LazyRef[T] { | ||
| var value: T = _ | ||
| @volatile var initialized: Boolean = false | ||
| @volatile private[this] var _initialized: Boolean = _ |
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Why is this @volatile btw?
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Quoting @retronym:
In double checked locking, the write to the value is in a synchronized block
the fast path (already initialized) just needs to volatile read on the initialized field. if that is set, we know the value was safely published
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Apologies, I guess what threw me of course is that this class (or rather these classes) are public, and non-final, classes which cannot be used properly without sprinkling of "magic"/macros. Are these intended to be possible to use directly by users?
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True, the runtime package is not meant for public consumption. Good point
that they should likely be final. They have to be public though, as they
are referenced from compiler-generated code.
allanrenucci
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Reduce the amount of code generated for local lazy val by moving some of the generated code to the runtime library. This is a port of scala/scala#5374
allanrenucci
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Reduce the amount of code generated for local lazy val by moving some of the generated code to the runtime library. This is a port of scala/scala#5374
allanrenucci
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Oct 31, 2018
Reduce the amount of code generated for local lazy val by moving some of the generated code to the runtime library. This is a port of scala/scala#5374
allanrenucci
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Nov 1, 2018
Reduce the amount of code generated for local lazy val by moving some of the generated code to the runtime library. This is a port of scala/scala#5374
allanrenucci
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Reduce the amount of code generated for local lazy val by moving some of the generated code to the runtime library. This is a port of scala/scala#5374
allanrenucci
added a commit
to dotty-staging/dotty
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Nov 1, 2018
Reduce the amount of code generated for local lazy val by moving some of the generated code to the runtime library. This is a port of scala/scala#5374
allanrenucci
added a commit
to dotty-staging/dotty
that referenced
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Nov 1, 2018
Reduce the amount of code generated for local lazy val by moving some of the generated code to the runtime library. This is a port of scala/scala#5374
allanrenucci
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Nov 6, 2018
Reduce the amount of code generated for local lazy val by moving some of the generated code to the runtime library. This is a port of scala/scala#5374
allanrenucci
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Reduce the amount of code generated for local lazy val by moving some of the generated code to the runtime library. This is a port of scala/scala#5374
allanrenucci
added a commit
to dotty-staging/dotty
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Nov 8, 2018
Reduce the amount of code generated for local lazy val by moving some of the generated code to the runtime library. This is a port of scala/scala#5374
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Follow up for #5294 based on @retronym's feedback.
I'm going to defer teaching the optimizer about stack allocating the lazy holders: scala/scala-dev#215