[FeatureRequest] Pad on broadcast dimensions are not well supported by codegen (both frontend / backend) about fuser HOT 3 CLOSED

It seems like this really calls for inferring a property on that IterDomain based on later uses within the Fusion which is a topic that comes up for dynamic shapes with other ops like view also. For instance we might mark the ID as "MaybeBroadcast" then when it is used later we would infer some potentially complicated relations between the inputs and the sizes and types of IDs. For pointwise binary ops the matching domains would imply that they match or at least one is a broadcast, for example. When we have processed the whole graph we can try and satisfy those relations and proceed as usual. So this issue is related to IterDomain graphs but with the new wrinkle that we may need to change the graph by changing whether to mark as bcast.

Exactly. Here's what I'm prototyping: https://github.com/NVIDIA/Fuser/compare/dynamic_reshape. I added a new IterType called Symbolic.

from fuser.

This functionality has existed for some time now.

from fuser.

It seems like this really calls for inferring a property on that IterDomain based on later uses within the Fusion which is a topic that comes up for dynamic shapes with other ops like view also. For instance we might mark the ID as "MaybeBroadcast" then when it is used later we would infer some potentially complicated relations between the inputs and the sizes and types of IDs. For pointwise binary ops the matching domains would imply that they match or at least one is a broadcast, for example. When we have processed the whole graph we can try and satisfy those relations and proceed as usual. So this issue is related to IterDomain graphs but with the new wrinkle that we may need to change the graph by changing whether to mark as bcast.

from fuser.