SILGen: Explicitly make fragile entities public when -sil-serialize-all is on

Previously IRGen would force all fragile entities to have public linkage.
It makes more sense to do this in SILGen instead, and only when
-sil-serialize-all is on.

Author: slavapestov

lib/SIL/SILDeclRef.cpp

@@ -324,8 +324,15 @@ SILLinkage SILDeclRef::getLinkage(ForDefinition_t forDefinition) const {
       if (isa<ClangModuleUnit>(derivedFor->getModuleScopeContext()))
         return ClangLinkage;
   }
-  
-  // Otherwise, we have external linkage.
+
+  // If the module is being built with -sil-serialize-all, everything has
+  // to have public linkage.
+  if (moduleContext->getParentModule()->getResilienceStrategy()
+      == ResilienceStrategy::Fragile) {
+    return (forDefinition ? SILLinkage::Public : SILLinkage::PublicExternal);
+  }
+
+  // Otherwise, linkage is determined by accessibility at the AST level.
   switch (d->getEffectiveAccess()) {
     case Accessibility::Private:
       return (forDefinition ? SILLinkage::Private : SILLinkage::PrivateExternal);

lib/SILGen/SILGen.cpp

@@ -854,9 +854,14 @@ SILFunction *SILGenModule::emitLazyGlobalInitializer(StringRef funcName,
   auto initSILType = getLoweredType(initType).castTo<SILFunctionType>();
 
   auto *f =
-      M.getOrCreateFunction(SILLinkage::Private, funcName, initSILType, nullptr,
+      M.getOrCreateFunction(makeModuleFragile
+                                ? SILLinkage::Public
+                                : SILLinkage::Private,
+                            funcName, initSILType, nullptr,
                             SILLocation(binding), IsNotBare, IsNotTransparent,
-                            makeModuleFragile ? IsFragile : IsNotFragile);
+                            makeModuleFragile
+                                ? IsFragile
+                                : IsNotFragile);
   f->setDebugScope(
       new (M) SILDebugScope(RegularLocation(binding->getInit(pbdEntry)), f));
   f->setLocation(binding);

lib/SILGen/SILGenGlobalVariable.cpp

@@ -224,7 +224,10 @@ void SILGenModule::emitGlobalInitialization(PatternBindingDecl *pd,
 
   // TODO: include the module in the onceToken's name mangling.
   // Then we can make it fragile.
-  auto onceToken = SILGlobalVariable::create(M, SILLinkage::Private,
+  auto onceToken = SILGlobalVariable::create(M,
+                                             makeModuleFragile
+                                                ? SILLinkage::Public
+                                                : SILLinkage::Private,
                                              makeModuleFragile,
                                              onceTokenBuffer, onceSILTy);
   onceToken->setDeclaration(false);

lib/SILGen/SILGenType.cpp

@@ -88,7 +88,10 @@ SILGenModule::emitVTableMethod(SILDeclRef derived, SILDeclRef base) {
   auto *derivedDecl = cast<AbstractFunctionDecl>(derived.getDecl());
   SILLocation loc(derivedDecl);
   auto thunk =
-      M.getOrCreateFunction(SILLinkage::Private, name, overrideInfo.SILFnType,
+      M.getOrCreateFunction(makeModuleFragile
+                                ? SILLinkage::Public
+                                : SILLinkage::Private,
+                            name, overrideInfo.SILFnType,
                             derivedDecl->getGenericParams(), loc, IsBare,
                             IsNotTransparent, IsNotFragile);
   thunk->setDebugScope(new (M) SILDebugScope(loc, thunk));

test/SILGen/fragile_globals.swift

@@ -11,9 +11,9 @@ var mygg = 29
 
 // Check if we have three tokens: 2 from the imported modules, one from mygg.
 
-// CHECK: sil_global private{{.*}} @globalinit_[[T1:.*]]_token0
-// CHECK: sil_global private{{.*}} @globalinit_[[T2:.*]]_token0
-// CHECK: sil_global private{{.*}} @globalinit_[[T3:.*]]_token0
+// CHECK: sil_global private @globalinit_[[T1:.*]]_token0
+// CHECK: sil_global [fragile] @globalinit_[[T2:.*]]_token0
+// CHECK: sil_global [fragile] @globalinit_[[T3:.*]]_token0
 
 public func sum() -> Int {
   return mygg + get_gg_a() + get_gg_b()

test/SILOptimizer/dead_inlined_func.swift

@@ -1,5 +1,5 @@
 // RUN: %target-swift-frontend -O -g %s -emit-sil | FileCheck %s -check-prefix=CHECK-SIL
-// RUN: %target-swift-frontend -O -g %s -sil-serialize-all -emit-ir | FileCheck %s -check-prefix=CHECK-IR
+// RUN: %target-swift-frontend -O -g %s -emit-ir | FileCheck %s -check-prefix=CHECK-IR
 
 // The dead inlined function should not be in the SIL
 // CHECK-SIL-NOT: sil {{.*}}to_be_inlined

test/Serialization/global_init.swift

@@ -19,8 +19,8 @@ var MyVar = 3
 // CHECK: let MyConst: Int
 // CHECK: var MyVar: Int
 
-// CHECK-DAG: sil hidden [fragile] [global_init] @_TF11global_initau7MyConstSi : $@convention(thin) () -> Builtin.RawPointer
-// CHECK-DAG: sil hidden [fragile] [global_init] @_TF11global_initau5MyVarSi : $@convention(thin) () -> Builtin.RawPointer
+// CHECK-DAG: sil [fragile] [global_init] @_TF11global_initau7MyConstSi : $@convention(thin) () -> Builtin.RawPointer
+// CHECK-DAG: sil [fragile] [global_init] @_TF11global_initau5MyVarSi : $@convention(thin) () -> Builtin.RawPointer
 
 func getGlobals() -> Int {
   return MyVar + MyConst

test/Serialization/serialize_attr.swift

@@ -52,6 +52,6 @@ class CC<T : PP> {
   }
 }
 
-// CHECK-DAG: sil hidden [fragile] [_specialize <Int, Float>] @_TF14serialize_attr14specializeThisu0_rFTx1uq__T_ : $@convention(thin) <T, U> (@in T, @in U) -> () {
+// CHECK-DAG: sil [fragile] [_specialize <Int, Float>] @_TF14serialize_attr14specializeThisu0_rFTx1uq__T_ : $@convention(thin) <T, U> (@in T, @in U) -> () {
 
-// CHECK-DAG: sil hidden [fragile] [noinline] [_specialize <RR, Float, SS, Int>] @_TFC14serialize_attr2CC3foouRd__S_2QQrfTqd__1gGVS_2GGx__Tqd__GS2_x__ : $@convention(method) <T where T : PP><U where U : QQ> (@in U, GG<T>, @guaranteed CC<T>) -> (@out U, GG<T>) {
+// CHECK-DAG: sil [fragile] [noinline] [_specialize <RR, Float, SS, Int>] @_TFC14serialize_attr2CC3foouRd__S_2QQrfTqd__1gGVS_2GGx__Tqd__GS2_x__ : $@convention(method) <T where T : PP><U where U : QQ> (@in U, GG<T>, @guaranteed CC<T>) -> (@out U, GG<T>) {

test/sil-extract/load-serialized-sil.swift

@@ -20,7 +20,7 @@
 
 
 
-// CHECK-LABEL: sil hidden [fragile] @_TFVs1X4testfT_T_ : $@convention(method) (X) -> ()
+// CHECK-LABEL: sil [fragile] @_TFVs1X4testfT_T_ : $@convention(method) (X) -> ()
 // CHECK: bb0
 // CHECK-NEXT: function_ref
 // CHECK-NEXT: function_ref @unknown : $@convention(thin) () -> ()

test/sil-opt/sil-opt.swift

@@ -18,7 +18,7 @@
 // CHECK: func unknown()
 // SIB-CHECK: func unknown()
 
-// CHECK-LABEL: sil hidden [fragile] @_TFVs1X4testfT_T_ : $@convention(method) (X) -> ()
+// CHECK-LABEL: sil [fragile] @_TFVs1X4testfT_T_ : $@convention(method) (X) -> ()
 // CHECK: bb0
 // CHECK-NEXT: function_ref
 // CHECK-NEXT: function_ref @unknown : $@convention(thin) () -> ()
@@ -36,7 +36,7 @@
 // CHECK: sil @unknown : $@convention(thin) () -> ()
 // SIB-CHECK: sil @unknown : $@convention(thin) () -> ()
 
-// CHECK: sil hidden [fragile] @_TFVs1XCfT_S_ : $@convention(thin) (@thin X.Type) -> X
+// CHECK: sil [fragile] @_TFVs1XCfT_S_ : $@convention(thin) (@thin X.Type) -> X
 // CHECK: bb0
 // CHECK-NEXT: struct $X ()
 // CHECK-NEXT: return