Runtimes: support generic metadata prespecialization for all of Core

Also provide a flag to enabled/disable it.

Addresses rdar://144255917

Author: edymtt

Runtimes/Core/CMakeLists.txt

@@ -103,6 +103,13 @@ option(SwiftCore_ENABLE_FILESYSTEM_SUPPORT "Build for systems that have a filesy
 option(SwiftCore_ENABLE_OS_TRACE_LAZY_INIT "Use os_trace call to check if lazy init has been completed before making os_signpost calls." ${SwiftCore_HAS_OS_TRACE})
 option(SwiftCore_HAS_DARWIN_LIBMALLOC "Use Darwin malloc features" ${APPLE})
 
+if("${APPLE}" OR "${LINUX}")
+  set(SwiftCore_ENABLE_PRESPECIALIZATION_default ON)
+else()
+  set(SwiftCore_ENABLE_PRESPECIALIZATION_default OFF)
+endif()
+option(SwiftCore_ENABLE_PRESPECIALIZATION "Enable generic metadata prespecialization" "${SwiftCore_ENABLE_PRESPECIALIZATION_default}")
+
 defaulted_option(SwiftCore_ENABLE_BACKTRACING "Enable backtracing runtime support")
 defaulted_set(SwiftCore_BACKTRACER_PATH STRING "Set a fixed path to the Swift backtracer")
 defaulted_option(SwiftCore_ENABLE_FATALERROR_BACKTRACE "Build stdlib fatalError with backtrace output")
@@ -181,7 +188,8 @@ add_compile_options(
   "$<$<COMPILE_LANGUAGE:Swift>:SHELL:-Xfrontend -target-min-inlining-version -Xfrontend min>"
   "$<$<AND:$<NOT:$<BOOL:${SwiftCore_ENABLE_OBJC_INTEROP}>>,$<COMPILE_LANGUAGE:Swift>>:SHELL:-Xfrontend -disable-objc-interop>"
   "$<$<AND:$<PLATFORM_ID:Windows>,$<COMPILE_LANGUAGE:Swift>>:SHELL:-Xcc -Xclang -Xcc -fbuiltin-headers-in-system-modules>"
-  "$<$<AND:$<BOOL:${SwiftCore_ENABLE_LIBRARY_EVOLUTION}>,$<COMPILE_LANGUAGE:Swift>>:-enable-library-evolution>")
+  "$<$<AND:$<BOOL:${SwiftCore_ENABLE_LIBRARY_EVOLUTION}>,$<COMPILE_LANGUAGE:Swift>>:-enable-library-evolution>"
+  "$<$<AND:$<BOOL:${SwiftCore_ENABLE_PRESPECIALIZATION}>,$<COMPILE_LANGUAGE:Swift>>:SHELL:-Xfrontend -prespecialize-generic-metadata>")
 
 include_directories(include)
 

Runtimes/Core/core/CMakeLists.txt

@@ -283,8 +283,7 @@ target_compile_options(swiftCore PRIVATE
   "$<$<COMPILE_LANGUAGE:Swift>:SHELL:-Xfrontend -group-info-path -Xfrontend ${CMAKE_CURRENT_SOURCE_DIR}/GroupInfo.json>"
   "$<$<COMPILE_LANGUAGE:Swift>:SHELL:-Xfrontend -disable-autolinking-runtime-compatibility-concurrency>"
   "$<$<COMPILE_LANGUAGE:Swift>:SHELL:-Xfrontend -disable-objc-attr-requires-foundation-module>"
-  "$<$<COMPILE_LANGUAGE:Swift>:SHELL:-Xfrontend -require-explicit-availability=ignore>"
-  "$<$<COMPILE_LANGUAGE:Swift>:SHELL:-Xfrontend -prespecialize-generic-metadata>")
+  "$<$<COMPILE_LANGUAGE:Swift>:SHELL:-Xfrontend -require-explicit-availability=ignore>")
 
 if(NOT "${CMAKE_BUILD_TYPE}" STREQUAL "MinSizeRel")
   # Using these in MinSizeRel would result in a 15% increase in the binary size