[pull] master from google:master #234
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This change reduces the amount of static allocation performed during app startup, and will potentially reduce runtime memory usage. Both of these arrays are passed into CGPInitializeEnumType(): - Each member of names is passed into JavaLangEnum_initWithNSString_withInt_() which retains the name. The original array itself is not persisted anywhere, and becomes superfluous as soon as CGPInitializeEnumType() returns - hence it's safe to allocate it on-demand on the stack instead of statically. (The allocation can occur at most once because we're inside +initialize and additionally guarded by a (self == concrete class) check, which guarantees we won't run the same thing for subclasses.) - Each member of int_values is likewise copied into the heap-allocated enum array (enumPtr in CGPInitializeEnumType), and the array itself is not persisted or used anywhere else. Similarly, there's no need to keep it alive. In an existing app, which makes heavy use of J2ObjC protos, we have: 1488 proto enums, and 26406 cases total. Therefore we would expect a memory consumption reduction of 26406 cases * (8 + 4 bytes) = 309KB. It's slightly hard to measure the effect at runtime as memory tests are inherently noisy - but we think we are able to observe a reduction of similar order of magnitude (as measured by task_vm_info.phys_footprint and task_vm_info.resident_size). There is scope for further similar changes around the various J2Objc protobuf generators in future - some changes will be equally simple (only in cases where no pointers to these arrays are being stored after +initialize), some changes will be much more involved (pointers to the currently static arrays inside e.g. j2objc_message are persisted forever). PiperOrigin-RevId: 394636759
This change reduces the amount of static allocation performed during app startup, and will potentially reduce runtime memory usage. Both of these arrays are passed into CGPInitializeOneofCaseEnum(): - Each member of names is passed into JavaLangEnum_initWithNSString_withInt_() which retains the name. The original array itself is not persisted anywhere, and becomes superfluous as soon as CGPInitializeOneofCaseEnum() returns - hence it's safe to allocate it on-demand on the stack instead of statically. (The allocation can occur at most once because we're inside +initialize and additionally guarded by a (self == concrete class) check, which guarantees we won't run the same thing for subclasses.) - Each member of int_values is likewise copied into the heap-allocated enum array (enumPtr in CGPInitializeEnumType), and the array itself is not persisted or used anywhere else. Similarly, there's no need to keep it alive. In an existing app, which makes heavy use of J2ObjC protos, we have: 165 oneofs, and 934 cases total. Therefore we would expect a memory consumption reduction of 934 cases * (8 + 4 bytes) = 10KB. That's unlikely to show up in memory tests. There is scope for further similar changes around the various J2Objc protobuf generators in future - some changes will be equally simple (only in cases where no pointers to these arrays are being stored after +initialize), some changes will be much more involved (pointers to the currently static arrays inside e.g. j2objc_message are persisted forever). PiperOrigin-RevId: 394644484
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