[cmake][llvm] Limit the number of Xcode schemes created by default (#101243)

CMake -GXcode would otherwise offer to create one scheme for each
target, which ends up being a lot. For now, limit the default to the
`check-*` LIT targets, plus `ALL_BUILD` and `install`.

For targets that aren't in the default list, we now have a configuration
variable to promote an extra list of targets into schemes, for example
`-DLLVM_XCODE_EXTRA_TARGET_SCHEMES="TargetParserTests;SupportTests"` to
add schemes for `TargetParserTests` and `SupportTests` respectively.

clang/cmake/modules/AddClang.cmake

@@ -147,6 +147,7 @@ endmacro(add_clang_library)
 macro(add_clang_executable name)
   add_llvm_executable( ${name} ${ARGN} )
   set_clang_windows_version_resource_properties(${name})
+  set_target_properties(${name} PROPERTIES XCODE_GENERATE_SCHEME ON)
 endmacro(add_clang_executable)
 
 macro(add_clang_tool name)
@@ -181,6 +182,7 @@ macro(add_clang_tool name)
       set_property(GLOBAL APPEND PROPERTY CLANG_EXPORTS ${name})
     endif()
   endif()
+  set_target_properties(${name} PROPERTIES XCODE_GENERATE_SCHEME ON)
 endmacro()
 
 macro(add_clang_symlink name dest)

lldb/cmake/modules/AddLLDB.cmake

@@ -258,6 +258,7 @@ function(add_lldb_tool name)
   endif()
 
   add_lldb_executable(${name} GENERATE_INSTALL ${ARG_UNPARSED_ARGUMENTS})
+  set_target_properties(${name} PROPERTIES XCODE_GENERATE_SCHEME ON)
 endfunction()
 
 # The test suite relies on finding LLDB.framework binary resources in the

llvm/CMakeLists.txt

@@ -1423,3 +1423,16 @@ endif()
 if (LLVM_INCLUDE_UTILS AND LLVM_INCLUDE_TOOLS)
   add_subdirectory(utils/llvm-locstats)
 endif()
+
+if (XCODE)
+  # For additional targets that you would like to add schemes, specify e.g:
+  #
+  #   -DLLVM_XCODE_EXTRA_TARGET_SCHEMES="TargetParserTests;SupportTests"
+  #
+  # at CMake configure time.
+  set(LLVM_XCODE_EXTRA_TARGET_SCHEMES "" CACHE STRING "Specifies an extra list of targets to turn into schemes")
+
+  foreach(target ${LLVM_XCODE_EXTRA_TARGET_SCHEMES})
+    set_target_properties(${target} PROPERTIES XCODE_GENERATE_SCHEME ON)
+  endforeach()
+endif()

llvm/cmake/modules/AddLLVM.cmake

@@ -1452,6 +1452,7 @@ macro(llvm_add_tool project name)
   endif()
   get_subproject_title(subproject_title)
   set_target_properties(${name} PROPERTIES FOLDER "${subproject_title}/Tools")
+  set_target_properties(${name} PROPERTIES XCODE_GENERATE_SCHEME ON)
 endmacro(llvm_add_tool project name)
 
 macro(add_llvm_tool name)
@@ -2043,6 +2044,7 @@ function(add_lit_target target comment)
 
   # Tests should be excluded from "Build Solution".
   set_target_properties(${target} PROPERTIES EXCLUDE_FROM_DEFAULT_BUILD ON)
+  set_target_properties(${target} PROPERTIES XCODE_GENERATE_SCHEME ON)
 endfunction()
 
 # Convert a target name like check-clang to a variable name like CLANG.