[embedded] Make CMO's 'serialize everything' mode even more aggressive and allow serialization of private and shared functions

test/embedded/modules-print-exec.swift

@@ -0,0 +1,50 @@
+// RUN: %empty-directory(%t)
+// RUN: %{python} %utils/split_file.py -o %t %s
+
+// RUN: %target-swift-frontend -emit-module -o %t/MyModule.swiftmodule %t/MyModule.swift -enable-experimental-feature Embedded -parse-as-library
+// RUN: %target-swift-frontend -c -I %t %t/Main.swift -enable-experimental-feature Embedded -o %t/a.o
+// RUN: %target-clang -x c -c %S/Inputs/tiny-runtime-dummy-refcounting.c -o %t/runtime.o
+// RUN: %target-clang -x c -c %S/Inputs/print.c -o %t/print.o
+// RUN: %target-clang %t/a.o %t/print.o %t/runtime.o -o %t/a.out
+// RUN: %target-run %t/a.out | %FileCheck %s
+
+// REQUIRES: executable_test
+// REQUIRES: VENDOR=apple
+// REQUIRES: OS=macosx
+
+// BEGIN MyModule.swift
+
+@_silgen_name("putchar")
+func putchar(_: UInt8)
+
+public func print(_ s: StaticString, terminator: StaticString) {
+  var p = s.utf8Start
+  while p.pointee != 0 {
+    putchar(p.pointee)
+    p += 1
+  }
+  p = terminator.utf8Start
+  while p.pointee != 0 {
+    putchar(p.pointee)
+    p += 1
+  }
+}
+
+@_silgen_name("print_long")
+func print_long(_: Int)
+
+public func print(_ n: Int, terminator: StaticString) {
+    print_long(n)
+    print("", terminator: terminator)
+}
+
+// BEGIN Main.swift
+
+import MyModule
+
+func test() {
+  print("Hello world", terminator: "\n") // CHECK: Hello world
+  print(42, terminator: "\n") // CHECK-NEXT: 42
+}
+
+test()