[compiler-rt] [cmake] Add cmake file for hexagon-builtins baremetal (PR #151500)

[via llvm-commits]

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@@ -0,0 +1,26 @@
+set(CMAKE_ASM_FLAGS "-G0 -mlong-calls -fno-pic" CACHE STRING "")
+set(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR ON CACHE BOOL "")
+set(LLVM_TARGET_TRIPLE hexagon-unknown-none-elf CACHE STRING "")
+set(COMPILER_RT_DEFAULT_TARGET_TRIPLE hexagon-unknown-none-elf CACHE STRING "")
+set(COMPILER_RT_BUILD_BUILTINS ON CACHE BOOL "")
+set(COMPILER_RT_BUILD_SANITIZERS OFF CACHE BOOL "")
+set(COMPILER_RT_BUILD_XRAY OFF CACHE BOOL "")
+set(COMPILER_RT_BUILD_LIBFUZZER OFF CACHE BOOL "")
+set(COMPILER_RT_BUILD_PROFILE OFF CACHE BOOL "")
+set(COMPILER_RT_BUILD_MEMPROF OFF CACHE BOOL "")
+set(COMPILER_RT_BUILD_ORC OFF CACHE BOOL "")
+set(COMPILER_RT_BUILD_GWP_ASAN OFF CACHE BOOL "")
+set(COMPILER_RT_BUILTINS_ENABLE_PIC OFF CACHE BOOL "")
+set(COMPILER_RT_SUPPORTED_ARCH hexagon CACHE STRING "")
+# without this, build tries to use pthread which is not supported by hexagon-unknown-none-elf
+set(COMPILER_RT_BAREMETAL_BUILD ON CACHE BOOL "" FORCE)
+
+set(CMAKE_C_FLAGS "-ffreestanding")
+set(CMAKE_CXX_FLAGS "-ffreestanding")
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quic-k wrote:

it works for now, but using CACHE value would be better

https://github.com/llvm/llvm-project/pull/151500