You can look to a couple places in code depending on what exactly you’re looking for.
You can see all of Glow’s Nodes here 22. But it generally makes more sense to see if a Node is supported on a specific backend, and with a specific precision.
So you can see whether a particular backend supports a Node with a specific precision by looking at Backend::isOpSupported(). For example, here is that function for our CPU backend 22.