Split current_thread into an inline fast path and a cold slow path - #13887
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Splitting current_thread into an #[inline] fast path plus #[cold] outlined deferred-promotion slow path reduces call overhead by about 20% (measured in a Linux VM on an M5 Max MBP): sync calls go from about 83ns to about 65ns, immediately ready async calls from 142ns to 117ns.
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Precompute `TypeFunc::contains_borrow` at compile time and use it in the hostcall entrypoint to skip `CallContext` scope push/pop and `validate_scope_exit` when lending is statically impossible. Relative to bytecodealliance#13887, this reduces call overhead by about 29% for sync calls, and about 9% for async calls (both measured in a Linux VM on an M5 Max MBP): sync calls go from about 65ns to about 46ns, immediately ready async calls from 117ns to 106ns. I'm not entirely sure why the win is so much less for async calls, but there are more wins in future commits.
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…ytecodealliance#13887) Splitting current_thread into an #[inline] fast path plus #[cold] outlined deferred-promotion slow path reduces call overhead by about 20% (measured in a Linux VM on an M5 Max MBP): sync calls go from about 83ns to about 65ns, immediately ready async calls from 142ns to 117ns.
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Splitting current_thread into an #[inline] fast path plus #[cold] outlined deferred-promotion slow path reduces call overhead by about 20% (measured in a Linux VM on an M5 Max MBP): sync calls go from about 83ns to about 65ns, immediately ready async calls from 142ns to 117ns.