[CMake] Add comments in llvm/CMakeLists.txt.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199594 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/CMakeLists.txt b/CMakeLists.txt
index afff7beb70744ace9124534edc99f402f2ad0b41..17aa0c8b7f3a8feef0e6ee9677d712a52e2459c8 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -92,16 +92,19 @@ endif()
 
 string(TOUPPER "${CMAKE_BUILD_TYPE}" uppercase_CMAKE_BUILD_TYPE)
 
-set(LLVM_MAIN_SRC_DIR ${CMAKE_CURRENT_SOURCE_DIR})
-set(LLVM_MAIN_INCLUDE_DIR ${LLVM_MAIN_SRC_DIR}/include)
-set(LLVM_BINARY_DIR ${CMAKE_CURRENT_BINARY_DIR})
+# They are used as destination of target generators.
+set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)
+set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
+
+# Each of them corresponds to llvm-config's.
+set(LLVM_MAIN_SRC_DIR     ${CMAKE_CURRENT_SOURCE_DIR}  ) # --src-root
+set(LLVM_MAIN_INCLUDE_DIR ${LLVM_MAIN_SRC_DIR}/include ) # --includedir
+set(LLVM_BINARY_DIR       ${CMAKE_CURRENT_BINARY_DIR}  ) # --prefix
+
 set(LLVM_EXAMPLES_BINARY_DIR ${LLVM_BINARY_DIR}/examples)
 set(LLVM_INCLUDE_DIR ${CMAKE_CURRENT_BINARY_DIR}/include)
 set(LLVM_LIBDIR_SUFFIX "" CACHE STRING "Define suffix of library directory name (32/64)" )
 
-set(LLVM_RUNTIME_OUTPUT_INTDIR ${LLVM_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)
-set(LLVM_LIBRARY_OUTPUT_INTDIR ${LLVM_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib)
-
 set(LLVM_ALL_TARGETS
   AArch64
   ARM