add 'atomic triple' for compare-and-set, and use it in one example

6 jobs for ci/for_proph in 13 minutes and 39 seconds
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passed #34511
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build-coq.8.10.dev

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passed #34515
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build-coq.8.7.2

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build-coq.8.8.2

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fp-timing
build-coq.8.9.0

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build-coq.8.9.1

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passed #34510
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build-coq.dev

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