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9ec9c0f5e5
`is_pub` added to `Fn` would cost us an additional 8 bytes of memory per function, which is a real bummer since it's only 1 bit of information. If we wanted to really remove this, I suspect we could make this a function isPub() which looks at the AST of the corresponding Decl and finds if the FnProto AST node has the pub token. However I saw an easier approach - The data of whether something is pub or not is actually a property of a Decl anyway, not a function, so we can look at moving the field into Decl. Indeed, doing this, we see that Decl already has deletion_flag: bool which is hiding in the padding bytes between the enum (1 byte) and the following u32 field (generation). So if we put the is_pub bool there, it actually will take up no additional space, with 1 byte of padding remaining. This was an easy reworking of the code since any func.is_pub could be changed simply to func.owner_decl.is_pub. I also modified `Var` to make the init value non-optional and moved the optional bit to a has_init: bool field. This is worse from the perspective of control flow and safety, however it makes `@sizeOf(Var)` go from 32 bytes to 24 bytes. The more code we can fit into memory at once, the more justified we are in using the compiler as a long-running process that does incremental updates.