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Due to lazy field type initialization, the `types` field is actually mutable in `DataType`. This means that we cannot use immutable or constant TBAA for all `DataType` fields. However, since any objects stored in the field are still rooted over the lifetime of the `DataType` we can still let the GC root placement pass refine any field to the parent `DataType`. Also make use of the field offset to still mark known load from all other fields as constant. This is currently done via a special case but it could also be useful for many other types too.
oscardssmith
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Aug 28, 2020
Due to lazy field type initialization, the `types` field is actually mutable in `DataType`. This means that we cannot use immutable or constant TBAA for all `DataType` fields. However, since any objects stored in the field are still rooted over the lifetime of the `DataType` we can still let the GC root placement pass refine any field to the parent `DataType`. Also make use of the field offset to still mark known load from all other fields as constant. This is currently done via a special case but it could also be useful for many other types too.
simeonschaub
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Aug 29, 2020
Due to lazy field type initialization, the `types` field is actually mutable in `DataType`. This means that we cannot use immutable or constant TBAA for all `DataType` fields. However, since any objects stored in the field are still rooted over the lifetime of the `DataType` we can still let the GC root placement pass refine any field to the parent `DataType`. Also make use of the field offset to still mark known load from all other fields as constant. This is currently done via a special case but it could also be useful for many other types too.
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Due to lazy field type initialization, the
typesfield is actually mutable inDataType.This means that we cannot use immutable or constant TBAA for all
DataTypefields.However, since any objects stored in the field are still rooted
over the lifetime of the
DataTypewe can still let the GC root placement pass refineany field to the parent
DataType.Also make use of the field offset to still mark known load from all other fields as constant.
This is currently done via a special case but it could also be useful for many other types too.
Ref #37044