[llvm] [Offload] Add CMake cache to be used in AMDGPU bot (PR #119369)

[Shilei Tian via llvm-commits]

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@@ -0,0 +1,13 @@
+set(LLVM_ENABLE_PROJECTS "clang;lld" CACHE STRING "")
+set(LLVM_ENABLE_RUNTIMES "compiler-rt;openmp;offload" CACHE STRING "")
+set(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR ON CACHE BOOL "")
+set(LLVM_ENABLE_ASSERTIONS ON CACHE BOOL "")
+set(LLVM_LIT_ARGS "-v --show-unsupported --timeout 100 --show-xfail -j 32" CACHE STRING "")
+set(LLVM_TARGETS_TO_BUILD "X86;AMDGPU" CACHE STRING "")
+
+set(CLANG_DEFAULT_LINKER "lld" CACHE STRING "")
+
+set(CMAKE_INSTALL_PREFIX /tmp/llvm.install.jpbot CACHE STRING "")
+set(CMAKE_BUILD_TYPE Release CACHE STRING "")
+set(CMAKE_C_COMPILER_LAUNCHER ccache CACHE STRING "")
+set(CMAKE_CXX_COMPILER_LAUNCHER ccache CACHE STRING "")
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shiltian wrote:

Yeah, that's a fair point. I wish CMake could make it an optional argument. `""` really doesn't look nice.

https://github.com/llvm/llvm-project/pull/119369