Massive CPU increase on latest version of JUCE

General JUCE discussion
3

The atomics were a great addition that solved a bunch of problems with the old system.

But! there’s actually a good chance they are adding a major overhead if you’re loading them constantly inside hot loops

If you have code like:

for (int sample = 0; sample < numSamples; ++sample)
    buffer[sample] *= gain->load();

The compiler won’t be able to optimize it, due to the nature of an atomic instruction.

Modifying the code to:

auto localGain = gain->load();

for (int sample = 0; sample < numSamples; ++sample)
    buffer[sample] *= localGain;

Should allow the compiler to bring back all these optimizations for the now-clean loop.

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