[CMake] Add configuration dirs as potential locations for llvm-lit and llvm-tblgen in standalone builds

[sgraenitz]

Summary

If the provided LLVM build-tree used a multi-configuration generator like Xcode, LLVM_TOOLS_BINARY_DIR will have a generator-specific placeholder to express CMAKE_CFG_INTDIR. Thus llvm-lit and llvm-tblgen won't be found.
D62878 exports the actual configuration types so we can fix the path and add them to the search paths for find_program().

[stella.stamenova]

LGTM

[sgraenitz]

IIUC Clang uses the same mechanism. Moving append_configuration_directories() to AddLLVM.cmake could help there too. We may consider it for the future once D62859 is through.

[xiaobai]

Seems fine to me

[sgraenitz]

lldb/cmake/modules/LLDBStandalone.cmake

67

How is this working on Windows anyway? It should be llvm-tblgen.exe there right?

[stella.stamenova]

lldb/cmake/modules/LLDBStandalone.cmake

67

Ah, good point. You should use llvm-tblgen${HOST_EXECUTABLE_SUFFIX} as the name. That will add the suffix when required.

[sgraenitz]

Add CMAKE_EXECUTABLE_SUFFIX when searching for llvm-tblgen

[sgraenitz]

lldb/cmake/modules/LLDBStandalone.cmake

67

Ok added the suffix. I can imaging CMake would do it automatically if necessary, but it's not documented.

lldb/cmake/modules/LLDBStandalone.cmake

+function(append_configuration_directories input_dir output_dirs)
+  set(dirs_list ${input_dir})
+  foreach(config_type ${LLVM_CONFIGURATION_TYPES})
+    string(REPLACE ${CMAKE_CFG_INTDIR} ${config_type} dir ${input_dir})
+    list(APPEND dirs_list ${dir})
+  endforeach()
+  set(${output_dirs} ${dirs_list} PARENT_SCOPE)
+endfunction()
+
 # If we are not building as a part of LLVM, build LLDB as an
 # standalone project, using LLVM as an external library:
 if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
   project(lldb)
 
   option(LLVM_INSTALL_TOOLCHAIN_ONLY "Only include toolchain files in the 'install' target." OFF)
 
   set(LLDB_PATH_TO_LLVM_BUILD "" CACHE PATH "Path to LLVM build tree")
if (CMAKE_SOURCE_DIR STREQUAL CMAKE_CURRENT_SOURCE_DIR)
   set(LLVM_MAIN_SRC_DIR ${LLVM_BUILD_MAIN_SRC_DIR} CACHE PATH "Path to LLVM source tree")
   set(LLVM_MAIN_INCLUDE_DIR ${LLVM_MAIN_INCLUDE_DIR} CACHE PATH "Path to llvm/include")
   set(LLVM_BINARY_DIR ${LLVM_BINARY_DIR} CACHE PATH "Path to LLVM build tree")
 
   set(lit_file_name "llvm-lit")
   if(CMAKE_HOST_WIN32 AND NOT CYGWIN)
     set(lit_file_name "${lit_file_name}.py")
   endif()
-  set(LLVM_DEFAULT_EXTERNAL_LIT "${LLVM_TOOLS_BINARY_DIR}/${lit_file_name}" CACHE PATH "Path to llvm-lit")
+
+  append_configuration_directories(${LLVM_TOOLS_BINARY_DIR} config_dirs)
+  find_program(lit_full_path ${lit_file_name} ${config_dirs} NO_DEFAULT_PATH)
+  set(LLVM_DEFAULT_EXTERNAL_LIT ${lit_full_path} CACHE PATH "Path to llvm-lit")
 
   if(CMAKE_CROSSCOMPILING)
     set(LLVM_NATIVE_BUILD "${LLDB_PATH_TO_LLVM_BUILD}/NATIVE")
     if (NOT EXISTS "${LLVM_NATIVE_BUILD}")
       message(FATAL_ERROR
         "Attempting to cross-compile LLDB standalone but no native LLVM build
         found. Please cross-compile LLVM as well.")
     endif()
 
     if (CMAKE_HOST_SYSTEM_NAME MATCHES "Windows")
       set(HOST_EXECUTABLE_SUFFIX ".exe")
     endif()
 
     if (NOT CMAKE_CONFIGURATION_TYPES)
       set(LLVM_TABLEGEN_EXE
         "${LLVM_NATIVE_BUILD}/bin/llvm-tblgen${HOST_EXECUTABLE_SUFFIX}")
     else()
       # NOTE: LLVM NATIVE build is always built Release, as is specified in
       # CrossCompile.cmake
       set(LLVM_TABLEGEN_EXE
         "${LLVM_NATIVE_BUILD}/Release/bin/llvm-tblgen${HOST_EXECUTABLE_SUFFIX}")
     endif()
   else()
-    find_program(LLVM_TABLEGEN_EXE "llvm-tblgen" ${LLVM_TOOLS_BINARY_DIR}
-      NO_DEFAULT_PATH)
+    set(tblgen_file_name "llvm-tblgen${CMAKE_EXECUTABLE_SUFFIX}")
+    append_configuration_directories(${LLVM_TOOLS_BINARY_DIR} config_dirs)
+    find_program(LLVM_TABLEGEN_EXE ${tblgen_file_name} ${config_dirs} NO_DEFAULT_PATH)
   endif()
 
   # They are used as destination of target generators.
   set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)
   set(LLVM_LIBRARY_OUTPUT_INTDIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/lib${LLVM_LIBDIR_SUFFIX})
   if(WIN32 OR CYGWIN)
     # DLL platform -- put DLLs into bin.
     set(LLVM_SHLIB_OUTPUT_INTDIR ${LLVM_RUNTIME_OUTPUT_INTDIR})