[clang] [HLSL] Add Offload distribution (PR #196640)

[Deric C. via cfe-commits]

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@@ -14,3 +14,30 @@ if (HLSL_ENABLE_DISTRIBUTION)
       "clang;hlsl-resource-headers;clangd"
       CACHE STRING "")
 endif()
+
+# Enable the offload test suite distribution. This produces a portable
+# install prefix containing all binaries and test files needed to run the
+# HLSL offload test suite on another machine.
+#
+# Install with:
+#   cmake --build build --target install-distribution
+#   cmake --build build --target install-offload-tools
+#   cmake --build build --target install-offload-test-suite
+#
+# Prerequisites on the target machine:
+#   - Python 3.6+
+#   - pip install lit pyyaml
+#   - GPU drivers (D3D12, Vulkan, or Metal depending on test suite)
+#   - For non-clang test suites: a DXC executable (clang-dxc is included)
+#
+# After installing, configure and run tests:
+#   cd <prefix>/share/hlsl-test-suite
+#   ./configure-test-suite.py --suite clang-d3d12
+#   lit run/test/clang-d3d12
+if (HLSL_ENABLE_OFFLOAD_DISTRIBUTION)
----------------
Icohedron wrote:

Perhaps there should be an additional check to ensure that the `OffloadTest` external project is enabled?
Check that `OffloadTest` is in `LLVM_EXTERNAL_PROJECTS`

https://github.com/llvm/llvm-project/pull/196640