[cmake] Fix host tool path with driver build on Windows (#199152)

On Windows, the llvm-shlib dylib build uses the llvm-nm host tool to
make all symbols visible by default. The LLVM_TOOL_LLVM_DRIVER_BUILD=ON
build would fail because $<TARGET_FILE:llvm-nm> was invalid. This change
passes the name of the symlink / executable copy as a custom property so
things work out and the llvm-nm.exe host tool can be found.

Author: rnk

clang-tools-extra/clang-tidy/misc/CMakeLists.txt

@@ -3,10 +3,10 @@ set(LLVM_LINK_COMPONENTS
   Support
   )
 
-setup_host_tool(clang-tidy-confusable-chars-gen CLANG_TIDY_CONFUSABLE_CHARS_GEN clang_tidy_confusable_chars_gen clang_tidy_confusable_chars_gen_target)
-
 add_subdirectory(ConfusableTable)
 
+setup_host_tool(clang-tidy-confusable-chars-gen CLANG_TIDY_CONFUSABLE_CHARS_GEN clang_tidy_confusable_chars_gen clang_tidy_confusable_chars_gen_target)
+
 include_directories(BEFORE "${CMAKE_CURRENT_SOURCE_DIR}/../../include-cleaner/include")
 
 add_custom_command(

clang-tools-extra/clang-tidy/misc/ConfusableTable/CMakeLists.txt

@@ -1,6 +1,6 @@
 set(LLVM_LINK_COMPONENTS Support)
 list(REMOVE_ITEM LLVM_COMMON_DEPENDS clang-tablegen-targets)
 
-add_llvm_executable(clang-tidy-confusable-chars-gen
+add_clang_executable(clang-tidy-confusable-chars-gen
   BuildConfusableTable.cpp
   )

llvm/cmake/modules/AddLLVM.cmake

@@ -1604,6 +1604,9 @@ macro(llvm_add_tool project name)
     )
     generate_llvm_objects(${name} ${ARGN})
     add_custom_target(${name} DEPENDS llvm-driver)
+    set_target_properties(${name} PROPERTIES
+      LLVM_TOOL_EXECUTABLE
+        "${LLVM_RUNTIME_OUTPUT_INTDIR}/${name}${CMAKE_EXECUTABLE_SUFFIX}")
   else()
     add_llvm_executable(${name} ${ARGN})
 
@@ -2797,7 +2800,12 @@ function(get_host_tool_path tool_name setting_name exe_var_name target_var_name)
     get_native_tool_path(${tool_name} exe_name)
     set(target_name host_${tool_name})
   else()
-    set(exe_name $<TARGET_FILE:${tool_name}>)
+    # Driver-built tools set this property in llvm_add_tool because their
+    # targets are utilities, not executable targets.
+    get_target_property(exe_name ${tool_name} LLVM_TOOL_EXECUTABLE)
+    if(NOT exe_name)
+      set(exe_name $<TARGET_FILE:${tool_name}>)
+    endif()
     set(target_name ${tool_name})
   endif()
   # Force setting the cache variable because they are only used for being