diff --git a/utils/bazel/llvm-project-overlay/.bazelignore b/utils/bazel/llvm-project-overlay/.bazelignore
index fad56edd2b71..f3d19a94233d 100644
--- a/utils/bazel/llvm-project-overlay/.bazelignore
+++ b/utils/bazel/llvm-project-overlay/.bazelignore
@@ -3,4 +3,4 @@ utils/bazel
 # Ignore third-party projects. These should be configured separately and some
 # include Bazel configs.
 libcxx/utils/google-benchmark
-third-party
+third-party/benchmark
diff --git a/utils/bazel/llvm-project-overlay/clang/BUILD.bazel b/utils/bazel/llvm-project-overlay/clang/BUILD.bazel
index 9fba1a865ea9..8de5cd5992ac 100644
--- a/utils/bazel/llvm-project-overlay/clang/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/clang/BUILD.bazel
@@ -1009,7 +1009,7 @@ cc_library(
         ":basic",
         ":frontend",
         "//llvm:Support",
-        "//llvm:gtest",
+        "//third-party/unittest:gtest",
     ],
 )
 
diff --git a/utils/bazel/llvm-project-overlay/clang/unittests/BUILD.bazel b/utils/bazel/llvm-project-overlay/clang/unittests/BUILD.bazel
index bf2d5ddb282e..4dfdab840db0 100644
--- a/utils/bazel/llvm-project-overlay/clang/unittests/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/clang/unittests/BUILD.bazel
@@ -30,9 +30,9 @@ cc_test(
         "//llvm:Core",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gmock",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -48,7 +48,7 @@ cc_library(
         "//clang:frontend",
         "//clang:testing",
         "//clang:tooling",
-        "//llvm:gtest",
+        "//third-party/unittest:gtest",
     ],
 )
 
@@ -68,8 +68,8 @@ cc_test(
         "//clang:tooling",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -87,8 +87,8 @@ cc_test(
         "//clang:frontend",
         "//clang:tooling",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -111,9 +111,9 @@ cc_test(
         "//clang:parse",
         "//clang:tooling",
         "//llvm:Support",
-        "//llvm:gmock",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -137,9 +137,9 @@ cc_test(
         "//llvm:Support",
         "//llvm:TestingADT",
         "//llvm:TestingSupport",
-        "//llvm:gmock",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -157,9 +157,9 @@ cc_test(
         "//llvm:Support",
         "//llvm:TestingSupport",
         "//llvm:config",
-        "//llvm:gmock",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -183,8 +183,8 @@ cc_test(
         "//clang:sema",
         "//llvm:Core",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -207,9 +207,9 @@ cc_test(
         "//clang:frontend",
         "//clang:tooling_core",
         "//llvm:Support",
-        "//llvm:gmock",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -231,9 +231,9 @@ cc_test(
         "//clang:sema",
         "//clang:serialization",
         "//llvm:Support",
-        "//llvm:gmock",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -257,9 +257,9 @@ cc_test(
         "//clang:serialization",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gmock",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -281,7 +281,7 @@ cc_library(
         "//clang:tooling",
         "//clang:tooling_core",
         "//llvm:Support",
-        "//llvm:gtest",
+        "//third-party/unittest:gtest",
     ],
 )
 
@@ -306,8 +306,8 @@ cc_test(
         "//clang:tooling",
         "//clang:tooling_refactoring",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -321,8 +321,8 @@ cc_test(
     deps = [
         "//clang:rewrite",
         "//clang:tooling",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -343,9 +343,9 @@ cc_test(
         "//clang:sema",
         "//clang:tooling",
         "//llvm:TestingSupport",
-        "//llvm:gmock",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -364,7 +364,7 @@ cc_library(
         "//clang:static_analyzer_frontend",
         "//clang:testing",
         "//clang:tooling",
-        "//llvm:gtest",
+        "//third-party/unittest:gtest",
     ],
 )
 
@@ -388,8 +388,8 @@ cc_test(
         "//clang:tooling",
         "//llvm:Support",
         "//llvm:config",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -421,9 +421,9 @@ cc_test(
         "//clang:transformer",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gmock",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -445,7 +445,7 @@ cc_library(
         "//clang:tooling",
         "//clang:tooling_core",
         "//llvm:Support",
-        "//llvm:gtest",
+        "//third-party/unittest:gtest",
     ],
 )
 
@@ -468,9 +468,9 @@ cc_test(
         "//clang:tooling_syntax",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gmock",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -496,9 +496,9 @@ cc_test(
         "//clang:tooling_syntax",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gmock",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -522,7 +522,7 @@ cc_test(
     deps = [
         "//clang:libclang",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
diff --git a/utils/bazel/llvm-project-overlay/llvm/BUILD.bazel b/utils/bazel/llvm-project-overlay/llvm/BUILD.bazel
index 8a6edcbe36a2..0b4871cd4c2d 100644
--- a/utils/bazel/llvm-project-overlay/llvm/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/llvm/BUILD.bazel
@@ -3700,8 +3700,8 @@ cc_binary(
         ":BinaryFormat",
         ":CodeGen",
         ":DebugInfo",
-        ":Debuginfod",
         ":DebugInfoDWARF",
+        ":Debuginfod",
         ":Demangle",
         ":MC",
         ":MCDisassembler",
@@ -4249,97 +4249,6 @@ cc_library(
     ],
 )
 
-# A hacky library to expose some internal headers of gtest to its own
-# implementation source files using a stripped include prefix rather than
-# file-relative-inclusion.
-#
-# FIXME: This file should be in `textual_hdrs` instead of `hdrs`, but
-# unfortunately that doesn't work with `strip_include_prefix`:
-# https://github.com/bazelbuild/bazel/issues/12424
-#
-# For now, simply disable parsing and header modules.
-cc_library(
-    name = "gtest_internal_headers",
-    testonly = True,
-    hdrs = ["utils/unittest/googletest/src/gtest-internal-inl.h"],
-    features = [
-        "-parse_headers",
-        "-header_modules",
-    ],
-    strip_include_prefix = "utils/unittest/googletest",
-)
-
-cc_library(
-    name = "gtest",
-    testonly = True,
-    srcs = glob(
-        [
-            "utils/unittest/googletest/include/**/*.h",
-            "utils/unittest/googletest/src/*.cc",
-        ],
-        exclude = [
-            "utils/unittest/googletest/src/gtest-all.cc",
-            "utils/unittest/googletest/include/gtest/gtest_pred_impl.h",
-        ],
-    ) + [
-    ],
-    hdrs = ["utils/unittest/googletest/include/gtest/gtest.h"],
-    copts = llvm_copts,
-    defines = [
-        "GTEST_HAS_RTTI=0",
-        "__STDC_LIMIT_MACROS",
-        "__STDC_CONSTANT_MACROS",
-    ] + select({
-        "@bazel_tools//src/conditions:windows": ["GTEST_USE_OWN_TR1_TUPLE=0"],
-        "//conditions:default": ["GTEST_USE_OWN_TR1_TUPLE=1"],
-    }),
-    includes = [
-        "include",
-        "utils/unittest/googletest/include",
-    ],
-    textual_hdrs = [
-        "utils/unittest/googletest/include/gtest/gtest_pred_impl.h",
-    ],
-    deps = [
-        ":Support",
-        ":gtest_internal_headers",
-    ],
-)
-
-cc_library(
-    name = "gtest_main",
-    testonly = True,
-    srcs = ["utils/unittest/UnitTestMain/TestMain.cpp"],
-    copts = llvm_copts,
-    deps = [
-        ":Support",
-        ":gmock",
-        ":gtest",
-    ],
-)
-
-cc_library(
-    name = "gmock",
-    testonly = True,
-    srcs = glob(
-        [
-            "utils/unittest/googlemock/include/**/*.h",
-            "utils/unittest/googlemock/src/*.cc",
-        ],
-        exclude = ["utils/unittest/googlemock/src/gmock-all.cc"],
-    ),
-    hdrs = [
-        "utils/unittest/googlemock/include/gmock/gmock.h",
-        "utils/unittest/googlemock/include/gmock/gmock-matchers.h",
-    ],
-    copts = llvm_copts,
-    includes = [
-        "include",
-        "utils/unittest/googlemock/include",
-    ],
-    deps = [":gtest"],
-)
-
 py_binary(
     name = "lit",
     testonly = True,
@@ -4355,7 +4264,7 @@ cc_library(
     copts = llvm_copts,
     deps = [
         ":Support",
-        ":gmock",
+        "//third-party/unittest:gmock",
     ],
 )
 
@@ -4373,8 +4282,8 @@ cc_library(
     deps = [
         ":Support",
         ":config",
-        ":gmock",
-        ":gtest",
+        "//third-party/unittest:gmock",
+        "//third-party/unittest:gtest",
     ],
 )
 
diff --git a/utils/bazel/llvm-project-overlay/llvm/unittests/BUILD.bazel b/utils/bazel/llvm-project-overlay/llvm/unittests/BUILD.bazel
index d18170963d8a..3478c1d050e9 100644
--- a/utils/bazel/llvm-project-overlay/llvm/unittests/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/llvm/unittests/BUILD.bazel
@@ -23,8 +23,8 @@ cc_test(
         "//llvm:Core",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -49,8 +49,8 @@ cc_test(
         "//llvm:Support",
         "//llvm:TestingSupport",
         "//llvm:TransformUtils",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -65,8 +65,8 @@ cc_test(
         "//llvm:AsmParser",
         "//llvm:Core",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -83,8 +83,8 @@ cc_test(
         "//llvm:BitWriter",
         "//llvm:Core",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -99,8 +99,8 @@ cc_test(
         "//llvm:BitstreamReader",
         "//llvm:BitstreamWriter",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -136,8 +136,8 @@ cc_test(
         "//llvm:Support",
         "//llvm:Target",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -162,8 +162,8 @@ cc_test(
         "//llvm:FileCheckLib",
         "//llvm:Support",
         "//llvm:Target",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -195,8 +195,8 @@ cc_test(
         "//llvm:ObjectYAML",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -206,8 +206,8 @@ cc_test(
     deps = [
         "//llvm:Debuginfod",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -225,8 +225,8 @@ cc_test(
         "//llvm:ExecutionEngine",
         "//llvm:Interpreter",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -251,8 +251,8 @@ cc_test(
         "//llvm:MCJIT",
         "//llvm:Passes",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -276,8 +276,8 @@ cc_test(
         "//llvm:OrcJIT",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -292,8 +292,8 @@ cc_test(
         "//llvm:FileCheckLib",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -320,8 +320,8 @@ cc_test(
         "//llvm:Support",
         "//llvm:TestingSupport",
         "//llvm:config",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -335,8 +335,8 @@ cc_test(
     deps = [
         "//llvm:LineEditor",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -353,8 +353,8 @@ cc_test(
         "//llvm:FrontendOpenMP",
         "//llvm:Passes",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -370,8 +370,8 @@ cc_test(
         "//llvm:Core",
         "//llvm:Linker",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -388,8 +388,8 @@ cc_test(
         "//llvm:MC",
         "//llvm:MCDisassembler",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -407,8 +407,8 @@ cc_test(
         "//llvm:Core",
         "//llvm:Support",
         "//llvm:Target",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -423,8 +423,8 @@ cc_test(
         "//llvm:Object",
         "//llvm:ObjectYAML",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -439,8 +439,8 @@ cc_test(
         "//llvm:Object",
         "//llvm:ObjectYAML",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -457,8 +457,8 @@ cc_test(
         "//llvm:ObjectYAML",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -515,8 +515,8 @@ cc_test(
         ":option_tests_gen",
         "//llvm:Option",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -531,9 +531,9 @@ cc_test(
         "//llvm:BitReader",
         "//llvm:Remarks",
         "//llvm:Support",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
         "//llvm:remark_linker",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -550,8 +550,8 @@ cc_test(
         "//llvm:ProfileData",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -584,8 +584,8 @@ cc_test(
         "//llvm:Support",
         "//llvm:TestingSupport",
         "//llvm:config",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -601,8 +601,8 @@ cc_test(
         "//llvm:AllTargetsCodeGens",
         "//llvm:Support",
         "//llvm:config",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -620,9 +620,9 @@ cc_test(
         ":automata_tables_gen",
         "//llvm:Support",
         "//llvm:TableGen",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
         "//llvm:tblgen",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -638,8 +638,8 @@ cc_test(
     ],
     deps = [
         "//llvm:AArch64CodeGen",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -655,8 +655,8 @@ cc_test(
     deps = [
         "//llvm:Support",
         "//llvm:TestingADT",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -680,8 +680,8 @@ cc_test(
         "//llvm:Support",
         "//llvm:TestingSupport",
         "//llvm:TransformUtils",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -706,7 +706,7 @@ cc_test(
         "//llvm:MCDisassembler",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gtest",
-        "//llvm:gtest_main",
+        "//third-party/unittest:gtest",
+        "//third-party/unittest:gtest_main",
     ],
 )
diff --git a/utils/bazel/llvm-project-overlay/mlir/unittests/BUILD.bazel b/utils/bazel/llvm-project-overlay/mlir/unittests/BUILD.bazel
index 32e0a141d82f..d938033771a1 100644
--- a/utils/bazel/llvm-project-overlay/mlir/unittests/BUILD.bazel
+++ b/utils/bazel/llvm-project-overlay/mlir/unittests/BUILD.bazel
@@ -19,9 +19,9 @@ cc_test(
     ]),
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:IR",
         "//mlir/test:TestDialect",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -34,7 +34,6 @@ cc_test(
     ]),
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:ControlFlowInterfaces",
         "//mlir:DLTIDialect",
         "//mlir:DataLayoutInterfaces",
@@ -43,6 +42,7 @@ cc_test(
         "//mlir:InferIntRangeInterface",
         "//mlir:InferTypeOpInterface",
         "//mlir:Parser",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -56,8 +56,8 @@ cc_test(
     deps = [
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:Support",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -70,11 +70,11 @@ cc_test(
     ]),
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:Analysis",
         "//mlir:FuncDialect",
         "//mlir:IR",
         "//mlir:Pass",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -86,9 +86,9 @@ cc_test(
         "Rewrite/*.h",
     ]),
     deps = [
-        "//llvm:gtest_main",
         "//mlir:IR",
         "//mlir:Rewrite",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -101,8 +101,8 @@ cc_test(
     ]),
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:Dialect",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -115,8 +115,8 @@ cc_test(
     ]),
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:MemRefDialect",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -129,9 +129,9 @@ cc_test(
     ]),
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:QuantOps",
         "//mlir:Transforms",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -143,10 +143,10 @@ cc_test(
         "Dialect/SCF/*.h",
     ]),
     deps = [
-        "//llvm:gtest_main",
         "//mlir:FuncDialect",
         "//mlir:Parser",
         "//mlir:SCFDialect",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -159,8 +159,8 @@ cc_test(
     ]),
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:SparseTensorUtils",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -173,10 +173,10 @@ cc_test(
     ]),
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:SPIRVDeserialization",
         "//mlir:SPIRVDialect",
         "//mlir:SPIRVSerialization",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -189,9 +189,9 @@ cc_test(
     ]),
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:FuncDialect",
         "//mlir:TransformDialect",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -204,8 +204,8 @@ cc_test(
     ]),
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:DialectUtils",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -260,10 +260,10 @@ cc_test(
         ":PassIncGen",
         "//llvm:Support",
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:IR",
         "//mlir:TableGen",
         "//mlir/test:TestDialect",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -275,13 +275,13 @@ cc_test(
         "Transforms/*.h",
     ]),
     deps = [
-        "//llvm:gtest_main",
         "//mlir:AffineAnalysis",
         "//mlir:IR",
         "//mlir:Parser",
         "//mlir:Pass",
         "//mlir:TransformUtils",
         "//mlir:Transforms",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -296,11 +296,11 @@ cc_test(
     ]),
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:AffineAnalysis",
         "//mlir:Analysis",
         "//mlir:IR",
         "//mlir:Parser",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -314,9 +314,9 @@ cc_test(
         "Conversion/*/*.h",
     ]),
     deps = [
-        "//llvm:gtest_main",
         "//mlir:ArithDialect",
         "//mlir:PDLToPDLInterp",
+        "//third-party/unittest:gtest_main",
     ],
 )
 
@@ -332,7 +332,6 @@ cc_test(
     ],
     deps = [
         "//llvm:TestingSupport",
-        "//llvm:gtest_main",
         "//mlir:AllPassesAndDialects",
         "//mlir:Analysis",
         "//mlir:ExecutionEngine",
@@ -341,5 +340,6 @@ cc_test(
         "//mlir:MemRefToLLVM",
         "//mlir:mlir_c_runner_utils",
         "//mlir:mlir_runner_utils",
+        "//third-party/unittest:gtest_main",
     ],
 )
diff --git a/utils/bazel/llvm-project-overlay/third-party/unittest/BUILD.bazel b/utils/bazel/llvm-project-overlay/third-party/unittest/BUILD.bazel
new file mode 100644
index 000000000000..fc025fc14c86
--- /dev/null
+++ b/utils/bazel/llvm-project-overlay/third-party/unittest/BUILD.bazel
@@ -0,0 +1,109 @@
+# 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
+
+package(default_visibility = ["//visibility:public"])
+
+licenses(["notice"])
+
+exports_files(["LICENSE.TXT"])
+
+# It may be tempting to add compiler flags here, but that should be avoided.
+# The necessary warnings and other compile flags should be provided by the
+# toolchain or the `.bazelrc` file. This is just a workaround until we have a
+# widely available feature to enable unlimited stack frame instead of using
+# this `Make` variable.
+llvm_copts = [
+    "$(STACK_FRAME_UNLIMITED)",
+]
+
+# A hacky library to expose some internal headers of gtest to its own
+# implementation source files using a stripped include prefix rather than
+# file-relative-inclusion.
+#
+# FIXME: This file should be in `textual_hdrs` instead of `hdrs`, but
+# unfortunately that doesn't work with `strip_include_prefix`:
+# https://github.com/bazelbuild/bazel/issues/12424
+#
+# For now, simply disable parsing and header modules.
+cc_library(
+    name = "gtest_internal_headers",
+    testonly = True,
+    hdrs = ["googletest/src/gtest-internal-inl.h"],
+    features = [
+        "-parse_headers",
+        "-header_modules",
+    ],
+    strip_include_prefix = "googletest",
+)
+
+cc_library(
+    name = "gtest",
+    testonly = True,
+    srcs = glob(
+        [
+            "googletest/include/**/*.h",
+            "googletest/src/*.cc",
+        ],
+        exclude = [
+            "googletest/src/gtest-all.cc",
+            "googletest/include/gtest/gtest_pred_impl.h",
+        ],
+    ) + [
+    ],
+    hdrs = ["googletest/include/gtest/gtest.h"],
+    copts = llvm_copts,
+    defines = [
+        "GTEST_HAS_RTTI=0",
+        "__STDC_LIMIT_MACROS",
+        "__STDC_CONSTANT_MACROS",
+    ] + select({
+        "@bazel_tools//src/conditions:windows": ["GTEST_USE_OWN_TR1_TUPLE=0"],
+        "//conditions:default": ["GTEST_USE_OWN_TR1_TUPLE=1"],
+    }),
+    includes = [
+        "googletest/include",
+        "include",
+    ],
+    textual_hdrs = [
+        "googletest/include/gtest/gtest_pred_impl.h",
+    ],
+    deps = [
+        ":gtest_internal_headers",
+        "//llvm:Support",
+    ],
+)
+
+cc_library(
+    name = "gtest_main",
+    testonly = True,
+    srcs = ["UnitTestMain/TestMain.cpp"],
+    copts = llvm_copts,
+    deps = [
+        ":gmock",
+        ":gtest",
+        "//llvm:Support",
+    ],
+)
+
+cc_library(
+    name = "gmock",
+    testonly = True,
+    srcs = glob(
+        [
+            "googlemock/include/**/*.h",
+            "googlemock/src/*.cc",
+        ],
+        exclude = ["googlemock/src/gmock-all.cc"],
+    ),
+    hdrs = [
+        "googlemock/include/gmock/gmock.h",
+        "googlemock/include/gmock/gmock-matchers.h",
+    ],
+    copts = llvm_copts,
+    includes = [
+        "googlemock/include",
+        "include",
+    ],
+    deps = [":gtest"],
+)