Revert to use add_llvm_library and revert linking LLVM libraries (#438)

Add cmake option EXCLUDE_LIBS_FROM_ALL to remove a specific llvm library
from llvm 'all'.

This PR partially reverts 743bd15.
This PR addresses #401, #417, #418, #422, and brings back SONAME.

Author: wenju-he

CMakeLists.txt

@@ -298,21 +298,23 @@ else()
   )
 endif()
 
-add_library(${TARGET_NAME} SHARED
-    ${TARGET_INCLUDE_FILES}
-    ${TARGET_SOURCE_FILES}
-    $<TARGET_OBJECTS:cl_headers>
-)
-
-# Same CRT compile option are reqiured to avoid link errors on Windows.
-# MD and MDd are choosed by default for release and debug build in LLVM.
-# If users set MT or MTd flags, they also need to add the flags for
-# opencl-clang sources using a custom macro set_msvc_crt_flags.
-if(COMMAND set_msvc_crt_flags)
-    set_msvc_crt_flags(${TARGET_NAME})
+set(EXCLUDE_LIBS_FROM_ALL "" CACHE STRING "Space-separated list of LLVM libraries to exclude from all")
+llvm_map_components_to_libnames(ALL_LLVM_LIBS all)
+if (NOT "${EXCLUDE_LIBS_FROM_ALL}" STREQUAL "")
+  list(REMOVE_ITEM ALL_LLVM_LIBS ${EXCLUDE_LIBS_FROM_ALL})
 endif()
+list(APPEND OPENCL_CLANG_LINK_LIBS ${ALL_LLVM_LIBS})
+
+add_llvm_library(${TARGET_NAME} SHARED
+  ${TARGET_INCLUDE_FILES}
+  ${TARGET_SOURCE_FILES}
+  $<TARGET_OBJECTS:cl_headers>
 
-add_dependencies(${TARGET_NAME} CClangCompileOptions)
+  DEPENDS CClangCompileOptions
+
+  LINK_LIBS
+    ${OPENCL_CLANG_LINK_LIBS}
+  )
 
 if (WIN32)
     # Enable compiler generation of Control Flow Guard security checks.
@@ -328,51 +330,6 @@ elseif(UNIX)
         LINK_FLAGS " -Wl,--no-undefined")
 endif(WIN32)
 
-# Enable new IN_LIST operator.
-cmake_policy(SET CMP0057 NEW)
-set(OTHER_LIBRARIES)
-if ("NVPTX" IN_LIST LLVM_TARGETS_TO_BUILD)
-    list(APPEND OTHER_LIBRARIES LLVMNVPTXCodeGen LLVMNVPTXDesc LLVMNVPTXInfo)
-endif()
-if ("AMDGPU" IN_LIST LLVM_TARGETS_TO_BUILD)
-    list(APPEND OTHER_LIBRARIES LLVMAMDGPUCodeGen LLVMAMDGPUAsmParser LLVMAMDGPUDesc LLVMAMDGPUInfo)
-endif()
-
-target_link_libraries( ${TARGET_NAME}
-                       LINK_PRIVATE
-                       ${OPENCL_CLANG_LINK_LIBS}
-                       LLVMX86CodeGen
-                       LLVMX86AsmParser
-                       LLVMX86Desc
-                       LLVMX86Info
-                       LLVMX86Disassembler
-                       LLVMAnalysis
-                       LLVMCodeGen
-                       LLVMCore
-                       LLVMipo
-                       LLVMInstCombine
-                       LLVMInstrumentation
-                       LLVMMC
-                       LLVMMCParser
-                       LLVMObjCARCOpts
-                       LLVMOption
-                       LLVMScalarOpts
-                       LLVMSupport
-                       LLVMTransformUtils
-                       LLVMVectorize
-                       LLVMAsmPrinter
-                       LLVMSelectionDAG
-                       LLVMMCDisassembler
-                       LLVMProfileData
-                       LLVMObject
-                       LLVMBitWriter
-                       LLVMIRReader
-                       LLVMAsmParser
-                       LLVMTarget
-                       LLVMBitReader
-                       ${OTHER_LIBRARIES}
-                      )
-
 install(FILES opencl_clang.h
         DESTINATION include/cclang
         COMPONENT ${TARGET_NAME})