[embedded] Ignore 'do not specialize' @_semantics attributes in embedded Swift mode #70810
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@swift-ci please test |
| @@ -500,6 +500,11 @@ static bool createsInfiniteSpecializationLoop(ApplySite Apply) { | |||
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| static bool shouldNotSpecialize(SILFunction *Callee, SILFunction *Caller, | |||
| SubstitutionMap Subs = {}) { | |||
| // Ignore "do not specialize" markers in embedded Swift -- specialization is | |||
| // mandatory. | |||
| if (Callee->getModule().getOptions().EmbeddedSwift) | |||
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Would be nice if we could do this for perf annotations too, but that's probably a separate patch.
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Hm, I wonder if there is actually anything to fix for perf annotations: (1) The stdlib only has a handful of functions with the "do not specialize" marker and they seem to mostly be slow paths that do cause allocations (and thus are not going to be usable in @noLocks or @noAllocations code anyway). (2) Non-stdlib code probably shouldn't use the "do not specialize" marker as it's an underscored attribute, and arguably it could be considered to be the user's problem if they use the marker and then try to use such a code in a perf-annotated function...
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@swift-ci please test |
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@swift-ci please test Windows platform |
We cannot allow the 'do not specialize' @_semantics attributes in embedded Swift because specialization is mandatory for soundness of the resulting compilations. The attached test crashes (triggers a "unexpected unspecialized function found during IRGen" assert) without the fix.
We have been a bit lucky that so far the parts of the stdlib that we have for embedded Swift didn't use these attributes, but I have observed that some other parts (e.g. Dictionary implementation) do use them, so we need to fix this problem.