Wrap some multi-line macros in `do { ... } while(0)` in `{codegen,compile}.c`

[picnixz]

Feature or enhancement

Proposal:

Follow-up from the following observation (I'm sending a PR just after):

There are similar patterns in compile.c, maybe it is also worth taking a look? 🤔

Originally posted by @sobolevn in #119981 (comment)

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

Linked PRs

• gh-120017: use 'do-while(0)' in some {codegen,compile}.c multi-line macros #120018

[picnixz]

Well, Nikita preferred a new one (see #119981 (comment)).

[picnixz]

Closing since it was completed. I won't backport it since I didn't backport the others.