[llvm] [docs] Stress out the branch naming scheme for Graphite. (PR #104499)

[Mircea Trofin via llvm-commits]

https://github.com/mtrofin created https://github.com/llvm/llvm-project/pull/104499

None

>From ce1cd0dc4ed8a8b4e6706ab16280f403d03360ca Mon Sep 17 00:00:00 2001
From: Mircea Trofin <mtrofin at google.com>
Date: Thu, 15 Aug 2024 13:22:04 -0700
Subject: [PATCH] [docs] Stress out the branch naming scheme for Graphite.

---
 llvm/docs/GitHub.rst | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/llvm/docs/GitHub.rst b/llvm/docs/GitHub.rst
index 14424f722abf63..7472fa9a05d2ec 100644
--- a/llvm/docs/GitHub.rst
+++ b/llvm/docs/GitHub.rst
@@ -23,6 +23,13 @@ intended to be able to support "stacked" pull-request. Do not create any branche
 llvm/llvm-project repository otherwise, please use a fork (see below). User branches that
 aren't associated with a pull-request **will be deleted**.
 
+Note: this is particularly necessary if using [Graphite](https://app.graphite.dev/).
+To make sure Graphite creates branches following the above pattern, use `gt config`
+then `Branch naming settings` and `Set a prefix for branch names`. Include the last
+`/`. Otherwise Graphite will fail to `gt submit`. If that happens, a simple way to
+unblock is to rename (`git -m <old name> <new name>`), and then checkout the branch
+and `gt track`.
+
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