Index: libcxx/utils/ci/buildkite-pipeline.yml
===================================================================
--- libcxx/utils/ci/buildkite-pipeline.yml
+++ libcxx/utils/ci/buildkite-pipeline.yml
@@ -18,493 +18,6 @@
 #
 
 steps:
-  #
-  # Light pre-commit tests for things like formatting or when people forget
-  # to update generated files.
-  #
-  - label: "Format"
-    command: "libcxx/utils/ci/run-buildbot check-format"
-    artifact_paths:
-      - "**/clang-format.patch"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    soft_fail:
-        - exit_status: 1
-    timeout_in_minutes: 120
-
-  - label: "Generated output"
-    command: "libcxx/utils/ci/run-buildbot check-generated-output"
-    artifact_paths:
-      - "**/generated_output.patch"
-      - "**/generated_output.status"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  #
-  # General testing with the default configuration, under all the supported
-  # Standard modes, with Clang and GCC. This catches most issues upfront.
-  # The goal of this step is to catch most issues while being very fast.
-  #
-  - wait
-
-  - label: "C++2b"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx2b"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "C++20"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx20"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "C++17"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx17"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "C++14"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx14"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "C++11"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx11"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "C++03"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx03"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "GCC 11 / C++latest"
-    command: "libcxx/utils/ci/run-buildbot generic-gcc"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  #
-  # All other supported configurations of libc++.
-  #
-  - wait
-
-  # Tests with the supported compilers.
-  - label: "GCC 11 / C++11"
-    command: "libcxx/utils/ci/run-buildbot generic-gcc-cxx11"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Clang 12"
-    command: "libcxx/utils/ci/run-buildbot generic-clang-12"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Clang 13"
-    command: "libcxx/utils/ci/run-buildbot generic-clang-13"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  # Tests with the sanitizers.
-  - label: "ASAN"
-    command: "libcxx/utils/ci/run-buildbot generic-asan"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "TSAN"
-    command: "libcxx/utils/ci/run-buildbot generic-tsan"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "UBSAN"
-    command: "libcxx/utils/ci/run-buildbot generic-ubsan"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  # Tests with the various supported ways to build libc++.
-  - label: "Bootstrapping build"
-    command: "libcxx/utils/ci/run-buildbot bootstrapping-build"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Legacy Lit configuration"
-    command: "libcxx/utils/ci/run-buildbot legacy-test-config"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Legacy standalone build"
-    command: "libcxx/utils/ci/run-buildbot legacy-standalone"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Legacy LLVM_ENABLE_PROJECTS build"
-    command: "libcxx/utils/ci/run-buildbot legacy-project-build"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  # Tests with various build configurations.
-  - label: "-fno-exceptions"
-    command: "libcxx/utils/ci/run-buildbot generic-noexceptions"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Modular build"
-    command: "libcxx/utils/ci/run-buildbot generic-modules"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Static libraries"
-    command: "libcxx/utils/ci/run-buildbot generic-static"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Assertions enabled"
-    command: "libcxx/utils/ci/run-buildbot generic-assertions"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Debug iterators"
-    command: "libcxx/utils/ci/run-buildbot generic-debug-iterators"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "With LLVM's libunwind"
-    command: "libcxx/utils/ci/run-buildbot generic-with_llvm_unwinder"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "32 bit"
-    command: "libcxx/utils/ci/run-buildbot generic-32bit"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Single-threaded"
-    command: "libcxx/utils/ci/run-buildbot generic-singlethreaded"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "No debug mode"
-    command: "libcxx/utils/ci/run-buildbot generic-no-debug"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "No filesystem"
-    command: "libcxx/utils/ci/run-buildbot generic-no-filesystem"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "No random device"
-    command: "libcxx/utils/ci/run-buildbot generic-no-random_device"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "No locale"
-    command: "libcxx/utils/ci/run-buildbot generic-no-localization"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "No Unicode"
-    command: "libcxx/utils/ci/run-buildbot generic-no-unicode"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "No wide characters"
-    command: "libcxx/utils/ci/run-buildbot generic-no-wide-characters"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  # Other non-testing CI jobs
-  - label: "Benchmarks"
-    command: "libcxx/utils/ci/run-buildbot benchmarks"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Documentation"
-    command: "libcxx/utils/ci/run-buildbot documentation"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "linux"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
   # Tests on non-Unix platforms
   - label: "Clang-cl (DLL)"
     command: "bash libcxx/utils/ci/run-buildbot clang-cl-dll"
@@ -530,8 +43,8 @@
           limit: 2
     timeout_in_minutes: 120
 
-  - label: "MinGW (DLL)"
-    command: "bash libcxx/utils/ci/run-buildbot mingw-dll"
+  - label: "Clang-cl (filesystem enabled, i128 disabled)"
+    command: "bash libcxx/utils/ci/run-buildbot clang-cl-fs-noi128"
     artifact_paths:
       - "**/test-results.xml"
     agents:
@@ -542,8 +55,8 @@
           limit: 2
     timeout_in_minutes: 120
 
-  - label: "MinGW (Static)"
-    command: "bash libcxx/utils/ci/run-buildbot mingw-static"
+  - label: "MinGW (DLL)"
+    command: "bash libcxx/utils/ci/run-buildbot mingw-dll"
     artifact_paths:
       - "**/test-results.xml"
     agents:
@@ -554,185 +67,12 @@
           limit: 2
     timeout_in_minutes: 120
 
-  - label: "MacOS x86_64"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx20"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-      os: "macos"
-      arch: "x86_64"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "MacOS arm64"
-    command: "libcxx/utils/ci/run-buildbot generic-cxx20"
-    artifact_paths:
-      - "**/test-results.xml"
-      - "**/*.abilist"
-    agents:
-      queue: "libcxx-builders"
-      os: "macos"
-      arch: "arm64"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  # Build with the configuration we use to generate libc++.dylib on Apple platforms
-  - label: "Apple system"
-    command: "libcxx/utils/ci/run-buildbot apple-system"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "macos"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  # Test back-deployment to older Apple platforms
-  - label: "Apple back-deployment macosx10.9"
-    command: "libcxx/utils/ci/run-buildbot apple-system-backdeployment-10.9"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "macos10.15" # TODO: For now, we're running the back-deployment tests for 10.9 on 10.15, because we don't have proper 10.9 machines
-      arch: "x86_64"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Apple back-deployment macosx10.15"
-    command: "libcxx/utils/ci/run-buildbot apple-system-backdeployment-10.15"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders"
-      os: "macos10.15"
-      arch: "x86_64"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "AArch64"
-    command: "libcxx/utils/ci/run-buildbot aarch64"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "aarch64"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "AArch64 -fno-exceptions"
-    command: "libcxx/utils/ci/run-buildbot aarch64-noexceptions"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "aarch64"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Armv8"
-    command: "libcxx/utils/ci/run-buildbot armv8"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "armv8l"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Armv8 -fno-exceptions"
-    command: "libcxx/utils/ci/run-buildbot armv8-noexceptions"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "armv8l"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Armv7"
-    command: "libcxx/utils/ci/run-buildbot armv7"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "armv8l" # Compiling for v7, running on v8 hardware
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "Armv7 -fno-exceptions"
-    command: "libcxx/utils/ci/run-buildbot armv7-noexceptions"
-    artifact_paths:
-      - "**/test-results.xml"
-    agents:
-      queue: "libcxx-builders-linaro-arm"
-      arch: "armv8l" # Compiling for v7, running on v8 hardware
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "AIX (32-bit)"
-    command: "libcxx/utils/ci/run-buildbot aix"
-    artifact_paths:
-      - "**/test-results.xml"
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    env:
-        OBJECT_MODE: "32"
-    agents:
-        queue: libcxx-builders
-        os: aix
-    retry:
-      automatic:
-        - exit_status: -1  # Agent was lost
-          limit: 2
-    timeout_in_minutes: 120
-
-  - label: "AIX (64-bit)"
-    command: "libcxx/utils/ci/run-buildbot aix"
+  - label: "MinGW (Static)"
+    command: "bash libcxx/utils/ci/run-buildbot mingw-static"
     artifact_paths:
       - "**/test-results.xml"
-    env:
-        OBJECT_MODE: "64"
     agents:
-        queue: libcxx-builders
-        os: aix
+      queue: "windows"
     retry:
       automatic:
         - exit_status: -1  # Agent was lost
Index: libcxx/utils/ci/run-buildbot
===================================================================
--- libcxx/utils/ci/run-buildbot
+++ libcxx/utils/ci/run-buildbot
@@ -94,22 +94,11 @@
           "${@}"
 }
 
-function generate-cmake-libcxx-win() {
-    # TODO: Clang-cl in MSVC configurations don't have access to compiler_rt
-    # builtins helpers for int128 division. See
-    # https://reviews.llvm.org/D91139#2429595 for a comment about longterm
-    # intent for handling the issue. In the meantime, define
-    # -D_LIBCPP_HAS_NO_INT128 (both when building the library itself and
-    # when building tests) to allow enabling filesystem for running tests,
-    # even if it uses a non-permanent ABI.
-
+function generate-cmake-libcxx-clang-cl() {
     generate-cmake-base \
           -DLLVM_ENABLE_RUNTIMES="libcxx" \
           -DCMAKE_C_COMPILER=clang-cl \
           -DCMAKE_CXX_COMPILER=clang-cl \
-          -DLIBCXX_ENABLE_FILESYSTEM=YES \
-          -DCMAKE_CXX_FLAGS="-D_LIBCPP_HAS_NO_INT128" \
-          -DLIBCXX_TEST_COMPILER_FLAGS="-D_LIBCPP_HAS_NO_INT128" \
           "${@}"
 }
 
@@ -605,13 +594,32 @@
     # correctly when libc++ visibility attributes indicate dllimport linkage
     # anyway), thus just disable the experimental library. Remove this
     # setting when cmake and the test driver does the right thing automatically.
-    generate-cmake-libcxx-win -DLIBCXX_ENABLE_EXPERIMENTAL_LIBRARY=OFF
+    generate-cmake-libcxx-clang-cl -DLIBCXX_ENABLE_EXPERIMENTAL_LIBRARY=OFF
     echo "+++ Running the libc++ tests"
     ${NINJA} -vC "${BUILD_DIR}" check-cxx
 ;;
 clang-cl-static)
     clean
-    generate-cmake-libcxx-win -DLIBCXX_ENABLE_SHARED=OFF
+    generate-cmake-libcxx-clang-cl -DLIBCXX_ENABLE_SHARED=OFF
+    echo "+++ Running the libc++ tests"
+    ${NINJA} -vC "${BUILD_DIR}" check-cxx
+;;
+clang-cl-fs-noi128)
+    clean
+    # TODO: Clang-cl in MSVC configurations don't have access to compiler_rt
+    # builtins helpers for int128 division. See
+    # https://reviews.llvm.org/D91139#2429595 for a comment about longterm
+    # intent for handling the issue. In the meantime, define
+    # -D_LIBCPP_HAS_NO_INT128 (both when building the library itself and
+    # when building tests) to allow enabling filesystem for running tests,
+    # even if it uses a non-permanent ABI.
+    # See clang-cl-dll above for explanation why disabling the experimental
+    # library.
+    generate-cmake-libcxx-clang-cl \
+          -DLIBCXX_ENABLE_EXPERIMENTAL_LIBRARY=OFF
+          -DLIBCXX_ENABLE_FILESYSTEM=YES \
+          -DCMAKE_CXX_FLAGS="-D_LIBCPP_HAS_NO_INT128" \
+          -DLIBCXX_TEST_COMPILER_FLAGS="-D_LIBCPP_HAS_NO_INT128"
     echo "+++ Running the libc++ tests"
     ${NINJA} -vC "${BUILD_DIR}" check-cxx
 ;;