Integrate LLVM at llvm/llvm-project@a21f9bfe29c2

Updates LLVM usage to match
[a21f9bfe29c2](llvm/llvm-project@a21f9bfe29c2)

PiperOrigin-RevId: 706059010

Author: tensorflower-gardener

third_party/llvm/generated.patch

@@ -1,55 +1 @@
 Auto generated patch. Do not edit or delete it, even if empty.
-diff -ruN --strip-trailing-cr a/utils/bazel/llvm-project-overlay/mlir/BUILD.bazel b/utils/bazel/llvm-project-overlay/mlir/BUILD.bazel
---- a/utils/bazel/llvm-project-overlay/mlir/BUILD.bazel
-+++ b/utils/bazel/llvm-project-overlay/mlir/BUILD.bazel
-@@ -5167,6 +5167,7 @@
-         ":FuncDialect",
-         ":FunctionInterfaces",
-         ":GPUDialect",
-+        ":GPUUtils",
-         ":IR",
-         ":LinalgDialect",
-         ":MemRefDialect",
-@@ -5795,6 +5796,7 @@
-         ":ExecutionEngineUtils",
-         ":FuncDialect",
-         ":GPUDialect",
-+        ":GPUUtils",
-         ":GPUPassIncGen",
-         ":GPUToLLVMIRTranslation",
-         ":IR",
-@@ -5829,6 +5831,26 @@
-     ]),
- )
- 
-+cc_library(
-+    name = "GPUUtils",
-+    srcs = glob(
-+        [
-+            "lib/Dialect/GPU/Utils/*.cpp",
-+        ],
-+    ),
-+    hdrs = glob(["include/mlir/Dialect/GPU/Utils/*.h"]),
-+    includes = ["include"],
-+    deps = [
-+      ":AffineDialect",
-+      ":ArithDialect",
-+      ":GPUDialect",
-+      ":IR",
-+      ":Support",
-+      ":VectorDialect",
-+      "//llvm:Support",
-+    ],
-+)
-+
- td_library(
-     name = "GPUTransformOpsTdFiles",
-     srcs = [
-@@ -6188,6 +6210,7 @@
-         ":FuncToLLVM",
-         ":GPUCommonTransforms",
-         ":GPUDialect",
-+        ":GPUUtils",
-         ":GPUTransforms",
-         ":IR",
-         ":LLVMCommonConversion",

third_party/llvm/workspace.bzl

@@ -4,8 +4,8 @@ load("//third_party:repo.bzl", "tf_http_archive")
 
 def repo(name):
     """Imports LLVM."""
-    LLVM_COMMIT = "bc29fc937c6cb4a210f80c93c79fc6ed97c801f8"
-    LLVM_SHA256 = "c52784eddf958532cb617befe65df12a7a350b7eacf0532c3a61efc921b2142c"
+    LLVM_COMMIT = "a21f9bfe29c2b9f1967952d12a5b7cb8f8b75202"
+    LLVM_SHA256 = "7039c2826841e473fe6431e36a2d8ba3746f200da53c481384f7f5d970e5bca1"
 
     tf_http_archive(
         name = name,