[HLSL] Add Offload distribution

[bob80905]

This PR adds a new distribution to the HLSL cmake file.
The purpose is so that we can portably distribute binaries to other machines so that offload testing can be optimized.
Assisted by: Github Copilot
This PR was inspired by @Icohedron 's comment here: llvm/offload-test-suite#1149 (comment)
This addresses llvm/offload-test-suite#1150

[llvmorg-github-actions]

@llvm/pr-subscribers-hlsl

@llvm/pr-subscribers-clang

Author: Joshua Batista (bob80905)

Changes

This PR adds a new distribution to the HLSL cmake file.
The purpose is so that we can portably distribute binaries to other machines so that offload testing can be optimized.
This addresses llvm/offload-test-suite#1150

---

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

1 Files Affected:

• (modified) clang/cmake/caches/HLSL.cmake (+27)

diff --git a/clang/cmake/caches/HLSL.cmake b/clang/cmake/caches/HLSL.cmake
index 24afcbbda2a40..2826a2ebd2296 100644
--- a/clang/cmake/caches/HLSL.cmake
+++ b/clang/cmake/caches/HLSL.cmake
@@ -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)
+  # Lit utilities (FileCheck, split-file, etc.) require LLVM_INSTALL_UTILS.
+  set(LLVM_INSTALL_UTILS ON CACHE BOOL "")
+  set(LLVM_DISTRIBUTION_COMPONENTS
+      "clang;hlsl-resource-headers;FileCheck;split-file;obj2yaml;not"
+      CACHE STRING "")
+endif()

[Icohedron]

The HLSL offload test suite distribution itself doesn't contain the tests. The install-offload-test-suite install target from the offload test suite installs the tests.

Suggested change

	# prefix containing the binaries and test data needed to run the HLSL
	# prefix containing the binaries, headers, and libs needed to run the HLSL