[llvm] [llvm][release] Add links to automatically built packages (PR #147719)

[David Spickett via llvm-commits]

================
@@ -45,9 +45,26 @@ def create_release(repo, release, tag=None, name=None, message=None):
         # Note that these lines are not length limited because if we do so, GitHub
         # assumes that should be how it is laid out on the page. We want GitHub to
         # do the reflowing for us instead.
+        #
+        # Once all the atuomatic binary builds have completed, the HTML comments
+        # in the text below will be removed to reveal the download links.
         message = dedent(
             """\
-LLVM {release} Release
+## LLVM {release} Release
+
+<!-- DOWNLOAD_LINKS_BEGIN
+**Linux:**
+* [x86_64](https://github.com/llvm/llvm-project/releases/download/llvmorg-{release}/LLVM-{release}-Linux-X64.tar.xz) ([signature](https://github.com/llvm/llvm-project/releases/download/llvmorg-{release}/LLVM-{release}-Linux-X64.tar.xz.jsonl))
+* [Arm64](https://github.com/llvm/llvm-project/releases/download/llvmorg-{release}/LLVM-{release}-Linux-ARM64.tar.xz) ([signature](https://github.com/llvm/llvm-project/releases/download/llvmorg-{release}/LLVM-{release}-Linux-ARM64.tar.xz.jsonl))
+
+**macOS:**
+* [Apple Silicon](https://github.com/llvm/llvm-project/releases/download/llvmorg-{release}/LLVM-{release}-macOS-ARM64.tar.xz) (ARM64) ([signature](https://github.com/llvm/llvm-project/releases/download/llvmorg-{release}/LLVM-{release}-macOS-ARM64.tar.xz.jsonl))
+* [Intel](https://github.com/llvm/llvm-project/releases/download/llvmorg-{release}/LLVM-{release}-macOS-X64.tar.xz) (x86-64) ([signature](https://github.com/llvm/llvm-project/releases/download/llvmorg-{release}/LLVM-{release}-macOS-X64.tar.xz.jsonl))
+DOWNLOAD_LINKS_END -->
+
+Download links for Linux and macOS will appear here when all the builds have completed. <!-- DOWNLOAD_LINKS_PLACEHOLDER -->
+
+For Windows, and any other variants of platform and architecture, check the full list of release packages at the bottom of this release page.
----------------
DavidSpickett wrote:

I've added links for the hand built packages, to be uncommented once they're uploaded.

I discovered that nesting HTML comments isn't a great idea, so I've changed the formatting to repeat the platform name on each line like "Linux x86", "Linux AArch64" etc. This means you can reveal just one line and it still makes sense.

I moved the pointer to the forum up higher, because I think people should know that earlier.

Removed the note about installers vs. archives for Windows because it was a pain to fit in, and the actual text it refers to is only a few lines below anyway. If people are still not finding it, we can improve that later.

https://github.com/llvm/llvm-project/pull/147719