installation: Accept separate install prefix for LLDB.framework

[vsk]

Summary

To support multi-arch (fat) builds of swift-lldb, the build script sets
up separate per-arch install directories, runs each arch-specific build,
and then lipo's together the contents.

Split up LLDB_FRAMEWORK_INSTALL_DIR into a prefix (this can be supplied
by the build script) and the final install location. The concatenated
path is called LLDB_FRAMEWORK_INSTALL_PATH.

The idea is to have the build script supply the prefix used for the lipo step,
and for lldb's cmake caches to specify the right install dir for a given target.

[vsk]

Hm, the new framework install prefix seems redundant with CMAKE_INSTALL_PREFIX. Let me see if they can be shared.

[vsk]

It looks like a framework-specific install prefix is required, as the install prefix for the framework is not always the same as the install prefix for the rest of the project.

[vsk]

This is still not right. build-script does not include the arch-specific destdir in the install prefix to begin with.

lldb/CMakeLists.txt

if (LLDB_ENABLE_PYTHON)
   add_dependencies(finish_swig swig_wrapper liblldb lldb-argdumper)
   set_target_properties(finish_swig swig_wrapper PROPERTIES FOLDER "lldb misc")
 
   # Ensure we do the python post-build step when building lldb.
   add_dependencies(lldb finish_swig)
 
   # Install the LLDB python module
   if(LLDB_BUILD_FRAMEWORK)
-    set(LLDB_PYTHON_INSTALL_PATH ${LLDB_FRAMEWORK_INSTALL_DIR}/LLDB.framework/Resources/Python)
+    set(LLDB_PYTHON_INSTALL_PATH ${LLDB_FRAMEWORK_INSTALL_PATH}/LLDB.framework/Resources/Python)
   else()
     set(LLDB_PYTHON_INSTALL_PATH ${LLDB_PYTHON_RELATIVE_PATH})
   endif()
   add_custom_target(lldb-python-scripts)
   add_dependencies(lldb-python-scripts finish_swig)
   install(DIRECTORY ${lldb_python_build_path}/../
           DESTINATION ${LLDB_PYTHON_INSTALL_PATH}
           COMPONENT lldb-python-scripts)

lldb/cmake/modules/AddLLDB.cmake

 endmacro()
 
 function(add_lldb_tool name)
   cmake_parse_arguments(ARG "ADD_TO_FRAMEWORK" "" "" ${ARGN})
   if(LLDB_BUILD_FRAMEWORK AND ARG_ADD_TO_FRAMEWORK)
     set(subdir LLDB.framework/Versions/${LLDB_FRAMEWORK_VERSION}/Resources)
     add_lldb_executable(${name}
       GENERATE_INSTALL
-      INSTALL_PREFIX ${LLDB_FRAMEWORK_INSTALL_DIR}/${subdir}
+      INSTALL_PREFIX ${LLDB_FRAMEWORK_INSTALL_PATH}/${subdir}
       ${ARG_UNPARSED_ARGUMENTS}
     )
     lldb_add_to_buildtree_lldb_framework(${name} ${subdir})
     return()
   endif()
 
   add_lldb_executable(${name} GENERATE_INSTALL ${ARG_UNPARSED_ARGUMENTS})
 endfunction()

lldb/cmake/modules/LLDBConfig.cmake

if(LLDB_BUILD_FRAMEWORK)
   # CMake 3.6 did not correctly emit POST_BUILD commands for Apple Framework targets
   # CMake < 3.8 did not have the BUILD_RPATH target property
   if(CMAKE_VERSION VERSION_LESS 3.8)
     message(FATAL_ERROR "LLDB_BUILD_FRAMEWORK is not supported on CMake < 3.8")
   endif()
 
   set(LLDB_FRAMEWORK_VERSION A CACHE STRING "LLDB.framework version (default is A)")
   set(LLDB_FRAMEWORK_BUILD_DIR bin CACHE STRING "Output directory for LLDB.framework")
+  set(LLDB_FRAMEWORK_INSTALL_PREFIX "" CACHE STRING "Prefix for the LLDB.framework install directory")
   set(LLDB_FRAMEWORK_INSTALL_DIR Library/Frameworks CACHE STRING "Install directory for LLDB.framework")
+  set(LLDB_FRAMEWORK_INSTALL_PATH "${LLDB_FRAMEWORK_INSTALL_PREFIX}${LLDB_FRAMEWORK_INSTALL_DIR}")
 
   get_filename_component(LLDB_FRAMEWORK_ABSOLUTE_BUILD_DIR ${LLDB_FRAMEWORK_BUILD_DIR} ABSOLUTE
     BASE_DIR ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR})
 
   # Essentially, emit the framework's dSYM outside of the framework directory.
   set(LLDB_DEBUGINFO_INSTALL_PREFIX ${CMAKE_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin CACHE STRING
       "Directory to emit dSYM files stripped from executables and libraries (Darwin Only)")
 endif()

lldb/cmake/modules/LLDBFramework.cmake

 message(STATUS "LLDB.framework: build path is '${LLDB_FRAMEWORK_ABSOLUTE_BUILD_DIR}'")
-message(STATUS "LLDB.framework: install path is '${LLDB_FRAMEWORK_INSTALL_DIR}'")
+message(STATUS "LLDB.framework: install path is '${LLDB_FRAMEWORK_INSTALL_PATH}'")
 message(STATUS "LLDB.framework: resources subdirectory is 'Versions/${LLDB_FRAMEWORK_VERSION}/Resources'")
 
 # Configure liblldb as a framework bundle
 set_target_properties(liblldb PROPERTIES
   FRAMEWORK ON
   FRAMEWORK_VERSION ${LLDB_FRAMEWORK_VERSION}
 
   OUTPUT_NAME LLDB

 
 # Used in llvm_add_library() to set default output directories for multi-config
 # generators. Overwrite to account for special framework output directory.
 set_output_directory(liblldb
   BINARY_DIR ${LLDB_FRAMEWORK_ABSOLUTE_BUILD_DIR}
   LIBRARY_DIR ${LLDB_FRAMEWORK_ABSOLUTE_BUILD_DIR}
 )
 
-lldb_add_post_install_steps_darwin(liblldb ${LLDB_FRAMEWORK_INSTALL_DIR})
+lldb_add_post_install_steps_darwin(liblldb ${LLDB_FRAMEWORK_INSTALL_PATH})
 
 # Affects the layout of the framework bundle (default is macOS layout).
 if(IOS)
   set_target_properties(liblldb PROPERTIES
     XCODE_ATTRIBUTE_IPHONEOS_DEPLOYMENT_TARGET "${IPHONEOS_DEPLOYMENT_TARGET}")
 else()
   set_target_properties(liblldb PROPERTIES
     XCODE_ATTRIBUTE_MACOSX_DEPLOYMENT_TARGET "${MACOSX_DEPLOYMENT_TARGET}")

lldb/source/API/CMakeLists.txt

 endif()
 
 if(LLDB_ENABLE_LUA)
   get_target_property(lldb_scripts_dir swig_wrapper_lua BINARY_DIR)
   set(lldb_lua_wrapper ${lldb_scripts_dir}/LLDBWrapLua.cpp)
 endif()
 
 if(LLDB_BUILD_FRAMEWORK)
-  set(option_install_prefix INSTALL_PREFIX ${LLDB_FRAMEWORK_INSTALL_DIR})
+  set(option_install_prefix INSTALL_PREFIX ${LLDB_FRAMEWORK_INSTALL_PATH})
   set(option_framework FRAMEWORK)
 endif()
 
 add_lldb_library(liblldb SHARED ${option_framework}
   SBAddress.cpp
   SBAttachInfo.cpp
   SBBlock.cpp
   SBBreakpoint.cpp