Change Arc to use compare_exchange instead of compare_and_swap #32643
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⌛ Testing commit 9a28d4e with merge b0d3170... |
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Change Arc to use compare_exchange instead of compare_and_swap This should slightly improve code generation on architectures with a weak memory model like ARM.
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Looks like the slaves disappeared for whatever mysterious reason they do so, but otherwise all tests passed, so merging manually. |
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| loop { | ||
| // check if the weak counter is currently "locked"; if so, spin. | ||
| if cur == usize::MAX { |
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If cur is ever usize::MAX, won't this just keep spinning forever and never reload the value of cur?
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Ah, good point, I'll make a PR to fix that.
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This should slightly improve code generation on architectures with a weak memory model like ARM.