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Hard memo memory reduction #258

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Merged
jbgi merged 3 commits into from
May 26, 2016
Merged

Hard memo memory reduction #258

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8532b16
hard memo memory reduction.
clinuxrulz May 26, 2016
f9d58bb
Merge branch 'functionaljava/master' into hard-memo
clinuxrulz May 26, 2016
19c372f
removed initialized
clinuxrulz May 26, 2016
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9 changes: 4 additions & 5 deletions core/src/main/java/fj/P1.java
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Original file line number Diff line number Diff line change
Expand Up @@ -268,19 +268,18 @@ public static <A> P1<A> memo(F0<A> f) {
}

static class Memo<A> extends P1<A> {
private final P1<A> self;
private volatile boolean initialized;
private volatile P1<A> self;
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@jbgi jbgi May 26, 2016 •
edited
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self need not be volatile because the memory barrier is already done via initialized.
But thinking of it, you could let self be volatile and remove initialized altogether, replacing the !initialized check by self != null. WDYT?

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@clinuxrulz clinuxrulz May 26, 2016

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Sounds good to me.

private A value;

Memo(P1<A> self) { this.self = self; }

@Override public final A _1() {
if (!initialized) {
if (self != null) {
synchronized (this) {
if (!initialized) {
if (self != null) {
A a = self._1();
value = a;
initialized = true;
self = null;
return a;
}
}
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