[llvm] [Bazel] Add support for Bzlmod (PR #88927)

[Keith Smiley via llvm-commits]

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@@ -0,0 +1,127 @@
+# This file is licensed under the Apache License v2.0 with LLVM Exceptions.
+# See https://llvm.org/LICENSE.txt for license information.
+# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+load("@bazel_tools//tools/build_defs/repo:local.bzl", "new_local_repository")
+load(":vulkan_sdk.bzl", "vulkan_sdk_setup")
+load(":configure.bzl", "llvm_configure", "DEFAULT_TARGETS")
+
+def _llvm_configure_extension_impl(ctx):
+    targets = []
+    patches = []
+    commit = ""
+    sha256 = ""
+
+    for module in ctx.modules:
+
+        # Aggregate targets and patches across imports.
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keith wrote:

it feels like this opens us up to a lot of complexity with how these are resolved, i wonder if instead we could allow users to "bring their own" checkout somehow? or at least limit this to only the root module adding patches?

https://github.com/llvm/llvm-project/pull/88927