[CMake] Fix weiredness in swift runtime linking for SourceKit libraries

SourceKit components are never built while bootstrapping stages. So it
doen't need to have stage 0 or 1 handling.

(cherry picked from commit 914a6fd)

Author: rintaro

tools/SourceKit/cmake/modules/AddSwiftSourceKit.cmake

@@ -154,8 +154,11 @@ function(add_sourcekit_swift_runtime_link_flags target path HAS_SWIFT_MODULES)
   endif()
 
   if(SWIFT_SWIFT_PARSER)
-    # Make sure we can find the early SwiftSyntax libraries.
-    target_link_directories(${target} PRIVATE "${SWIFT_PATH_TO_EARLYSWIFTSYNTAX_BUILD_DIR}/lib/swift/host")
+    # Add rpath to the host Swift libraries.
+    if (NOT SWIFT_HOST_VARIANT_SDK IN_LIST SWIFT_DARWIN_PLATFORMS)
+      file(RELATIVE_PATH relative_hostlib_path "${path}" "${SWIFTLIB_DIR}/host")
+      list(APPEND RPATH_LIST "$ORIGIN/${relative_hostlib_path}")
+    endif()
 
     # Add rpath to the host Swift libraries.
     if (NOT ${SWIFT_HOST_VARIANT_SDK} IN_LIST SWIFT_DARWIN_PLATFORMS)
@@ -166,25 +169,16 @@ function(add_sourcekit_swift_runtime_link_flags target path HAS_SWIFT_MODULES)
     # For the "end step" of bootstrapping configurations on Darwin, need to be
     # able to fall back to the SDK directory for libswiftCore et al.
     if (BOOTSTRAPPING_MODE MATCHES "BOOTSTRAPPING.*")
-      if (NOT "${bootstrapping}" STREQUAL "1")
-        if(SWIFT_HOST_VARIANT_SDK IN_LIST SWIFT_DARWIN_PLATFORMS)
-          target_link_directories(${target} PRIVATE "${sdk_dir}")
-
-          # Include the abi stable system stdlib in our rpath.
-          set(swift_runtime_rpath "/usr/lib/swift")
-
-          # Add in the toolchain directory so we can grab compatibility libraries
-          get_filename_component(TOOLCHAIN_BIN_DIR ${SWIFT_EXEC_FOR_SWIFT_MODULES} DIRECTORY)
-          get_filename_component(TOOLCHAIN_LIB_DIR "${TOOLCHAIN_BIN_DIR}/../lib/swift/${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_LIB_SUBDIR}" ABSOLUTE)
-          target_link_directories(${target} PUBLIC ${TOOLCHAIN_LIB_DIR})
-        else()
-          get_filename_component(swift_bin_dir ${SWIFT_EXEC_FOR_SWIFT_MODULES} DIRECTORY)
-          get_filename_component(swift_dir ${swift_bin_dir} DIRECTORY)
-          set(host_lib_dir "${swift_dir}/lib/swift/${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_LIB_SUBDIR}")
-          target_link_directories(${target} PUBLIC ${host_lib_dir})
-
-          list(APPEND RPATH_LIST "${host_lib_dir}")
-        endif()
+      if(SWIFT_HOST_VARIANT_SDK IN_LIST SWIFT_DARWIN_PLATFORMS)
+        target_link_directories(${target} PRIVATE "${sdk_dir}")
+
+        # Include the abi stable system stdlib in our rpath.
+        set(swift_runtime_rpath "/usr/lib/swift")
+
+        # Add in the toolchain directory so we can grab compatibility libraries
+        get_filename_component(TOOLCHAIN_BIN_DIR ${SWIFT_EXEC_FOR_SWIFT_MODULES} DIRECTORY)
+        get_filename_component(TOOLCHAIN_LIB_DIR "${TOOLCHAIN_BIN_DIR}/../lib/swift/${SWIFT_SDK_${SWIFT_HOST_VARIANT_SDK}_LIB_SUBDIR}" ABSOLUTE)
+        target_link_directories(${target} PUBLIC ${TOOLCHAIN_LIB_DIR})
       endif()
     endif()
   endif()