[llvm] [Bazel] Migrate to Bzlmod (PR #88927)

[Jordan Rupprecht via llvm-commits]

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@@ -0,0 +1,125 @@
+# 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 = []
+
+    # Aggregate targets across imports.
+    targets.extend([
+        target
+        for module in ctx.modules 
+        for config in module.tags.configure 
+        for target in config.targets 
+        if target not in targets
+    ])
+
+    # Fall back to the default targets if all configurations of this extension
+    # omit the `target` attribute.
+    if targets == []:
+        targets = DEFAULT_TARGETS
+
+    llvm_configure(name = "llvm-project", targets = targets)
+
+    # Deliberately omit the "llvm-raw" directory if we're not in the utils/bazel
+    # directory.
+    #
+    # In downstream repos this intentionally causes the extension to immediately
+    # error out if "llvm-raw" wasn't injected explicitly.
+    #
+    # We can't add this repo to the utils/bazel/MODULE.bazel as it would cause
+    # submodule imports to resolve the new_local_repository at wrong paths.
+    [
+        new_local_repository(
+            name = "llvm-raw",
+            path = "../..",
+            build_file_content = "# Empty."
+        )
+        for module in ctx.modules
+        if module.name == "llvm-project-overlay" and module.is_root
+    ]
+
+    print(ctx.path(Label("@llvm-raw//:BUILD.bazel")))
+
+    http_archive(
+        name = "vulkan_headers",
+        build_file = "@llvm-raw//utils/bazel/third_party_build:vulkan_headers.BUILD",
+        sha256 = "19f491784ef0bc73caff877d11c96a48b946b5a1c805079d9006e3fbaa5c1895",
+        strip_prefix = "Vulkan-Headers-9bd3f561bcee3f01d22912de10bb07ce4e23d378",
+        urls = [
+            "https://github.com/KhronosGroup/Vulkan-Headers/archive/9bd3f561bcee3f01d22912de10bb07ce4e23d378.tar.gz",
+        ],
+    )
+
+    vulkan_sdk_setup(name = "vulkan_sdk")
+
+    http_archive(
+        name = "gmp",
+        build_file = "@llvm-raw//utils/bazel/third_party_build:gmp.BUILD",
+        sha256 = "fd4829912cddd12f84181c3451cc752be224643e87fac497b69edddadc49b4f2",
+        strip_prefix = "gmp-6.2.1",
+        urls = [
+            "https://gmplib.org/download/gmp/gmp-6.2.1.tar.xz",
+            "https://ftp.gnu.org/gnu/gmp/gmp-6.2.1.tar.xz",
+        ],
+    )
+
+    # https://www.mpfr.org/mpfr-current/
+    #
+    # When updating to a newer version, don't use URLs with "mpfr-current" in them.
+    # Instead, find a stable URL like the one used currently.
+    http_archive(
+        name = "mpfr",
+        build_file = "@llvm-raw//utils/bazel/third_party_build:mpfr.BUILD",
+        sha256 = "9cbed5d0af0d9ed5e9f8dd013e17838eb15e1db9a6ae0d371d55d35f93a782a7",
+        strip_prefix = "mpfr-4.1.1",
+        urls = ["https://www.mpfr.org/mpfr-4.1.1/mpfr-4.1.1.tar.gz"],
+    )
+
+    http_archive(
+        name = "pfm",
+        build_file = "@llvm-raw//utils/bazel/third_party_build:pfm.BUILD",
+        sha256 = "d18b97764c755528c1051d376e33545d0eb60c6ebf85680436813fa5b04cc3d1",
+        strip_prefix = "libpfm-4.13.0",
+        urls = ["https://versaweb.dl.sourceforge.net/project/perfmon2/libpfm4/libpfm-4.13.0.tar.gz"],
+    )
+
+    http_archive(
+        name = "pybind11",
+        build_file = "@llvm-raw//utils/bazel/third_party_build:pybind.BUILD",
+        sha256 = "201966a61dc826f1b1879a24a3317a1ec9214a918c8eb035be2f30c3e9cfbdcb",
+        strip_prefix = "pybind11-2.10.3",
+        url = "https://github.com/pybind/pybind11/archive/v2.10.3.zip",
+    )
+
+    # TODO: Make `NB_BUILD=1` and `NB_SHARED=1` configurable in the BCR variant
+    #       and import this via `MODULE.bazel`.
----------------
rupprecht wrote:

Not sure what this comment means, would you mind clarifying?

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