Atomic operations on Pointers #37683
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For some reason,
Threadsdoesn't support atomic operations through general pointers. However, we need these operations in order to e.g. atomically operate on array entries.While doing that, I noticed that llvm supports perfectly fine
atomicrmw faddandfsubintrinsics. These also boil down to acasloop on x86_64, but the emitted assembly looks nicer for the llvm intrinsic than for the julia loop, so I took the liberty to change that as well (I don't expect significant performance changes for that).Ref https://discourse.julialang.org/t/scattered-atomic-writes-into-array/46990/ and #32455