[TBDGen] Include materializeForSet closures.

This is a hack around IRGen's inadequacies, for the moment.

Author: huonw

include/swift/SILGen/SILGenMaterializeForSet.h

@@ -0,0 +1,29 @@
+//===- SILGenMaterializeForSet.h - SILGen for materializeForSet -*- C++ -*-===//
+//
+// This source file is part of the Swift.org open source project
+//
+// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+//
+//===----------------------------------------------------------------------===//
+
+#include <string>
+
+namespace swift {
+class ProtocolConformance;
+class FuncDecl;
+
+namespace Lowering {
+/// \brief Compute the name of the callback inside an auto-generated
+/// materializeForSet accessor.
+///
+/// FIXME: this should just be a static function inside
+/// SILGenMaterializeForSet.cpp, but currently these closures end up public,
+/// so TBDGen wants to emit them.
+std::string getMaterializeForSetCallbackName(ProtocolConformance *conformance,
+                                             FuncDecl *requirement);
+}
+}

lib/SILGen/SILGenMaterializeForSet.cpp

@@ -171,16 +171,15 @@
 #include "swift/SIL/SILArgument.h"
 #include "swift/SIL/SILUndef.h"
 #include "swift/SIL/TypeLowering.h"
+#include "swift/SILGen/SILGenMaterializeForSet.h"
 #include "llvm/Support/raw_ostream.h"
 #include "ASTVisitor.h"
 using namespace swift;
 using namespace Lowering;
 
-namespace {
-
-static std::string
-getMaterializeForSetCallbackName(ProtocolConformance *conformance,
-                                 FuncDecl *requirement) {
+std::string
+Lowering::getMaterializeForSetCallbackName(ProtocolConformance *conformance,
+                                           FuncDecl *requirement) {
 
   DeclContext *dc = requirement;
   ClosureExpr closure(/*patterns*/ nullptr,
@@ -209,6 +208,8 @@ getMaterializeForSetCallbackName(ProtocolConformance *conformance,
                                  Mangle::ASTMangler::SymbolKind::Default);
 }
 
+namespace {
+
 /// A helper class for emitting materializeForSet.
 ///
 /// The formal type of materializeForSet is:

lib/TBDGen/TBDGen.cpp

@@ -26,6 +26,7 @@
 #include "swift/SIL/SILDeclRef.h"
 #include "swift/SIL/SILWitnessTable.h"
 #include "swift/SIL/TypeLowering.h"
+#include "swift/SILGen/SILGenMaterializeForSet.h"
 #include "llvm/ADT/StringSet.h"
 
 using namespace swift;
@@ -285,6 +286,15 @@ void TBDGenVisitor::visitAbstractStorageDecl(AbstractStorageDecl *ASD) {
   InsideAbstractStorageDecl = true;
   visitMembers(ASD);
   InsideAbstractStorageDecl = false;
+
+  // IRGen currently promotes serialized private functions to public, which
+  // includes the closures inside materializeForSets of computed properties.
+  if (auto MFS = ASD->getMaterializeForSetFunc()) {
+    if (!isPrivateDecl(MFS)) {
+      addSymbol(Lowering::getMaterializeForSetCallbackName(
+          /*conformance=*/nullptr, MFS));
+    }
+  }
 }
 void TBDGenVisitor::visitVarDecl(VarDecl *VD) {
   // statically/globally stored variables have some special handling.