CMake: Add option for selecting LLVM version.

CMakeLists.txt

@@ -149,10 +149,13 @@ else()
 endif()
 
 set(DEFAULT_REACTOR_BACKEND "LLVM")
-
 set(REACTOR_BACKEND ${DEFAULT_REACTOR_BACKEND} CACHE STRING "JIT compiler back-end used by Reactor")
 set_property(CACHE REACTOR_BACKEND PROPERTY STRINGS LLVM Subzero)
 
+set(DEFAULT_SWIFTSHADER_LLVM_VERSION "7.0")
+set(SWIFTSHADER_LLVM_VERSION ${DEFAULT_SWIFTSHADER_LLVM_VERSION} CACHE STRING "LLVM version to use")
+set_property(CACHE SWIFTSHADER_LLVM_VERSION PROPERTY STRINGS "7.0" "10.0")
+
 # If defined, overrides the default optimization level of the current reactor backend.
 # Set to one of the rr::Optimization::Level enum values.
 set(REACTOR_DEFAULT_OPT_LEVEL "Default" CACHE STRING "Reactor default optimization level")
@@ -345,8 +348,6 @@ set(OPENGL_COMPILER_DIR ${OPENGL_DIR}/compiler)
 set(VULKAN_DIR ${SOURCE_DIR}/Vulkan)
 set(THIRD_PARTY_DIR ${CMAKE_CURRENT_SOURCE_DIR}/third_party)
 set(ASTC_DIR ${THIRD_PARTY_DIR}/astc-encoder)
-set(LLVM_DIR ${THIRD_PARTY_DIR}/llvm-7.0/llvm)
-set(LLVM_CONFIG_DIR ${THIRD_PARTY_DIR}/llvm-7.0/configs)
 set(LIBBACKTRACE_DIR ${THIRD_PARTY_DIR}/libbacktrace/src)
 set(LIBBACKTRACE_CONFIG_DIR ${THIRD_PARTY_DIR}/libbacktrace/config)
 set(LIBBACKTRACE_INCLUDE_DIR ${THIRD_PARTY_DIR}/libbacktrace/src)
@@ -593,7 +594,7 @@ endif()
 ###########################################################
 # LLVM
 ###########################################################
-add_subdirectory(third_party/llvm-7.0)
+add_subdirectory(third_party/llvm-${SWIFTSHADER_LLVM_VERSION})
 
 
 ###########################################################

third_party/llvm-7.0/CMakeLists.txt

@@ -12,6 +12,9 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+set(LLVM_DIR ${CMAKE_CURRENT_SOURCE_DIR}/llvm)
+set(LLVM_CONFIG_DIR ${CMAKE_CURRENT_SOURCE_DIR}/configs)
+
 set(LLVM_LIST
     ${LLVM_DIR}/lib/Analysis/AliasAnalysis.cpp
     ${LLVM_DIR}/lib/Analysis/AliasAnalysisSummary.cpp