The bufferization of arith.constant ops is also switched over to BufferizableOpInterface-based bufferization. The old implementation is deleted. Both implementations utilize GlobalCreator, now renamed to just getGlobalFor.
GlobalCreator no longer maintains a set of all created allocations to avoid duplicate allocations of the same constant. Instead, getGlobalFor scans the module to see if there is already a global allocation with the same constant value.
For compatibility reasons, it is still possible to create a pass that bufferizes only arith.constant. This pass (createConstantBufferizePass) could be deleted once all users were switched over to One-Shot bufferization.