Merging r323053:

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r323053 | dhinton | 2018-01-20 16:29:00 -0800 (Sat, 20 Jan 2018) | 9 lines

[cmake] Don't build Native llvm-config when cross compiling if passed by user.

Summary:
Rename LLVM_CONFIG_EXE to LLVM_CONFIG_PATH, and avoid building it if
passed in by user.  This is the same way CLANG_TABLEGEN and
LLVM_TABLEGEN are handled, e.g., when -DLLVM_OPTIMIZED_TABLEGEN=ON is
passed.

Differential Revision: https://reviews.llvm.org/D41806
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git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_60@332568 91177308-0d34-0410-b5e6-96231b3b80d8

Author: tstellar

tools/llvm-config/CMakeLists.txt

@@ -65,18 +65,17 @@ endif()
 # Add the dependency on the generation step.
 add_file_dependencies(${CMAKE_CURRENT_SOURCE_DIR}/llvm-config.cpp ${BUILDVARIABLES_OBJPATH})
 
-if(CMAKE_CROSSCOMPILING)
-  set(${project}_LLVM_CONFIG_EXE "${LLVM_NATIVE_BUILD}/bin/llvm-config")
-  set(${project}_LLVM_CONFIG_EXE ${${project}_LLVM_CONFIG_EXE} PARENT_SCOPE)
+if(CMAKE_CROSSCOMPILING AND NOT LLVM_CONFIG_PATH)
+  set(LLVM_CONFIG_PATH "${LLVM_NATIVE_BUILD}/bin/llvm-config" CACHE STRING "")
 
-  add_custom_command(OUTPUT "${${project}_LLVM_CONFIG_EXE}"
+  add_custom_command(OUTPUT "${LLVM_CONFIG_PATH}"
     COMMAND ${CMAKE_COMMAND} --build . --target llvm-config --config $<CONFIGURATION>
     DEPENDS ${LLVM_NATIVE_BUILD}/CMakeCache.txt
     WORKING_DIRECTORY ${LLVM_NATIVE_BUILD}
     COMMENT "Building native llvm-config..."
     USES_TERMINAL)
-  add_custom_target(${project}NativeLLVMConfig DEPENDS ${${project}_LLVM_CONFIG_EXE})
-  add_dependencies(${project}NativeLLVMConfig CONFIGURE_LLVM_NATIVE)
+  add_custom_target(NativeLLVMConfig DEPENDS ${LLVM_CONFIG_PATH})
+  add_dependencies(NativeLLVMConfig CONFIGURE_LLVM_NATIVE)
 
-  add_dependencies(llvm-config ${project}NativeLLVMConfig)
-endif(CMAKE_CROSSCOMPILING)
+  add_dependencies(llvm-config NativeLLVMConfig)
+endif()