[llvm] [docs] Update docs on code-review process (PR #111735)

[Andrzej Warzyński via llvm-commits]

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@@ -150,14 +150,21 @@ almost always associated with a message containing the text "LGTM" (which
 stands for Looks Good To Me). Only approval from a single reviewer is required.
 
 When providing an unqualified LGTM (approval to commit), it is the
-responsibility of the reviewer to have reviewed all of the discussion and
+responsibility of the reviewer to have reviewed all of the prior discussion and
 feedback from all reviewers ensuring that all feedback has been addressed and
 that all other reviewers will almost surely be satisfied with the patch being
 approved. If unsure, the reviewer should provide a qualified approval, (e.g.,
 "LGTM, but please wait for @someone, @someone_else"). You may also do this if
 you are fairly certain that a particular community member will wish to review,
 even if that person hasn't done so yet.
 
+If new comments are posted after the patch has been approved (but not yet
----------------
banach-space wrote:

Hi @preames , thanks for that suggestion and sorry for the delay - I had to step away and re-think this a bit. I do want to incorporate your feedback, but also want to make sure we avoid duplication and keep this document succinct. So I trimmed your suggestion a bit as per the comments below (hope this won't come across as nit-picking).

**Point 1:**
> [From Phillip's suggestion]
> Only approval from a single reviewer is required; 

This point is already mentioned earlier in the document: https://github.com/llvm/llvm-project/blob/c2063de1593610eda0f4de33c3b89324642ed54c/llvm/docs/CodeReview.rst?plain=1#L148-L150
 
**Point 2:**
> [From Phillip's suggestion]
> however the patch author is always responsible for making sure that all feedback on a review has been properly addressed or responded to. 

Isn't this a contradicting one existing policy?
https://github.com/llvm/llvm-project/blob/c2063de1593610eda0f4de33c3b89324642ed54c/llvm/docs/CodeReview.rst?plain=1#L152-L159

Specifically:

> it is the responsibility of the reviewer to have reviewed all of the discussion and feedback from all reviewers ensuring that all feedback has been addressed and that all other reviewers will almost surely be satisfied with the patch being approved.

I'd just leave this out.

**Point 3:**

> [From Phillip's suggestion]
> Similarly, the patch author is responsible for incorporating post commit feedback on the change.

This is already covered here: https://github.com/llvm/llvm-project/blob/c2063de1593610eda0f4de33c3b89324642ed54c/llvm/docs/CodeReview.rst?plain=1#L46-L49

**Point 4:**

Which leaves this bit from Phillip's original suggestion (emphasis mine):
> [From Phillip's suggestion]
If additional feedback is provided after acceptance (by the same reviewer or another), **the author should use their best judgement** in deciding whether that feedback can be incorporated into the change without comment (say a typo) or requires further review discussion. 

This a bit softer requirement compared to what I added "these need to be addressed" and sounds more along the lines of what @kuhar would prefer? Let me use that, but let me add small clarification at the end. Let me know what you think.

https://github.com/llvm/llvm-project/pull/111735