[embedded] Allow serialization of SILLinkage::shared functions without promoting them to public

Author: kubamracek

lib/SILOptimizer/IPO/CrossModuleOptimization.cpp

@@ -491,7 +491,7 @@ void CrossModuleOptimization::serializeFunction(SILFunction *function,
   if (function->isSerialized())
     return;
 
-  if (!canSerializeFlags.lookup(function))
+  if (!everything && !canSerializeFlags.lookup(function))
     return;
 
   function->setSerialized(IsSerialized);
@@ -588,9 +588,14 @@ void CrossModuleOptimization::keepMethodAlive(SILDeclRef method) {
 
 void CrossModuleOptimization::makeFunctionUsableFromInline(SILFunction *function) {
   assert(canUseFromInline(function));
-  if (!isAvailableExternally(function->getLinkage()) &&
-      function->getLinkage() != SILLinkage::Public) {
-    function->setLinkage(SILLinkage::Public);
+  if (!isAvailableExternally(function->getLinkage())) {
+    bool shouldPromoteToPublic = function->getLinkage() != SILLinkage::Public;
+    if (everything)
+      shouldPromoteToPublic = function->getLinkage() != SILLinkage::Public &&
+                              function->getLinkage() != SILLinkage::Shared;
+    if (shouldPromoteToPublic) {
+      function->setLinkage(SILLinkage::Public);
+    }
   }
 }
 

test/embedded/shared-linkage.swift

@@ -0,0 +1,49 @@
+// RUN: %empty-directory(%t)
+// RUN: %{python} %utils/split_file.py -o %t %s
+
+// RUN: %target-swift-frontend -emit-module -o %t/Module.swiftmodule %t/Module.swift -enable-experimental-feature Embedded
+// RUN: %target-swift-frontend -emit-ir %t/Main.swift -I%t -enable-experimental-feature Embedded
+
+// RUN: %target-swift-frontend -O -emit-module -o %t/Module.swiftmodule %t/Module.swift -enable-experimental-feature Embedded
+// RUN: %target-swift-frontend -O -emit-ir %t/Main.swift -I%t -enable-experimental-feature Embedded
+
+// RUN: %target-swift-frontend -Osize -emit-module -o %t/Module.swiftmodule %t/Module.swift -enable-experimental-feature Embedded
+// RUN: %target-swift-frontend -Osize -emit-ir %t/Main.swift -I%t -enable-experimental-feature Embedded
+
+// REQUIRES: swift_in_compiler
+// REQUIRES: VENDOR=apple
+// REQUIRES: OS=macosx
+
+// BEGIN Module.swift
+
+public func bar<R>(count: Int, _ body: (UnsafeMutableBufferPointer<Int>) -> R) -> R {
+  let pointer = UnsafeMutablePointer<Int>(bitPattern: 42)!
+  let inoutBufferPointer = UnsafeMutableBufferPointer(start: pointer, count: count)
+  return body(inoutBufferPointer)
+}
+
+public func foo<R>(_ body: () -> R) -> R {
+  bar(count: 10) { p in
+    body()
+  }
+}
+
+public func module_func() {
+  foo {
+    return 0
+  }
+}
+
+// BEGIN Main.swift
+
+import Module
+
+public func test() {
+  module_func()
+}
+
+public func client_func() {
+  foo {
+    return 0
+  }
+}