Fix for PR7415: refactor CodeGenModule::MayDeferGeneration and make it less

conservative for static variables in templated classes.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@106385 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index fbd80ed8d5b213eb22cebd6526c183aa8d6e615e..28f73d688c281a0f9361a5375527a4bb660cdda4 100644 (file)
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -590,6 +590,47 @@ llvm::Constant *CodeGenModule::EmitAnnotateAttr(llvm::GlobalValue *GV,
   return llvm::ConstantStruct::get(VMContext, Fields, 4, false);
 }
 
+static CodeGenModule::GVALinkage
+GetLinkageForVariable(ASTContext &Context, const VarDecl *VD) {
+  // If this is a static data member, compute the kind of template
+  // specialization. Otherwise, this variable is not part of a
+  // template.
+  TemplateSpecializationKind TSK = TSK_Undeclared;
+  if (VD->isStaticDataMember())
+    TSK = VD->getTemplateSpecializationKind();
+
+  Linkage L = VD->getLinkage();
+  if (L == ExternalLinkage && Context.getLangOptions().CPlusPlus &&
+      VD->getType()->getLinkage() == UniqueExternalLinkage)
+    L = UniqueExternalLinkage;
+
+  switch (L) {
+  case NoLinkage:
+  case InternalLinkage:
+  case UniqueExternalLinkage:
+    return CodeGenModule::GVA_Internal;
+
+  case ExternalLinkage:
+    switch (TSK) {
+    case TSK_Undeclared:
+    case TSK_ExplicitSpecialization:
+      return CodeGenModule::GVA_StrongExternal;
+
+    case TSK_ExplicitInstantiationDeclaration:
+      llvm_unreachable("Variable should not be instantiated");
+      // Fall through to treat this like any other instantiation.
+        
+    case TSK_ExplicitInstantiationDefinition:
+      return CodeGenModule::GVA_ExplicitTemplateInstantiation;
+
+    case TSK_ImplicitInstantiation:
+      return CodeGenModule::GVA_TemplateInstantiation;      
+    }
+  }
+
+  return CodeGenModule::GVA_StrongExternal;
+}
+
 bool CodeGenModule::MayDeferGeneration(const ValueDecl *Global) {
   // Never defer when EmitAllDecls is specified or the decl has
   // attribute used.
@@ -638,24 +679,10 @@ bool CodeGenModule::MayDeferGeneration(const ValueDecl *Global) {
     }
   }
       
-  // Static data may be deferred, but out-of-line static data members
-  // cannot be.
-  Linkage L = VD->getLinkage();
-  if (L == ExternalLinkage && getContext().getLangOptions().CPlusPlus &&
-      VD->getType()->getLinkage() == UniqueExternalLinkage)
-    L = UniqueExternalLinkage;
-
-  switch (L) {
-  case NoLinkage:
-  case InternalLinkage:
-  case UniqueExternalLinkage:
-    // Initializer has side effects?
-    if (VD->getInit() && VD->getInit()->HasSideEffects(Context))
-      return false;
-    return !(VD->isStaticDataMember() && VD->isOutOfLine());
-
-  case ExternalLinkage:
-    break;
+  GVALinkage L = GetLinkageForVariable(getContext(), VD);
+  if (L == GVA_Internal || L == GVA_TemplateInstantiation) {
+    if (!(VD->getInit() && VD->getInit()->HasSideEffects(Context)))
+      return true;
   }
 
   return false;
@@ -1053,47 +1080,6 @@ CodeGenModule::getVTableLinkage(const CXXRecordDecl *RD) {
   return llvm::GlobalVariable::WeakODRLinkage;
 }
 
-static CodeGenModule::GVALinkage
-GetLinkageForVariable(ASTContext &Context, const VarDecl *VD) {
-  // If this is a static data member, compute the kind of template
-  // specialization. Otherwise, this variable is not part of a
-  // template.
-  TemplateSpecializationKind TSK = TSK_Undeclared;
-  if (VD->isStaticDataMember())
-    TSK = VD->getTemplateSpecializationKind();
-
-  Linkage L = VD->getLinkage();
-  if (L == ExternalLinkage && Context.getLangOptions().CPlusPlus &&
-      VD->getType()->getLinkage() == UniqueExternalLinkage)
-    L = UniqueExternalLinkage;
-
-  switch (L) {
-  case NoLinkage:
-  case InternalLinkage:
-  case UniqueExternalLinkage:
-    return CodeGenModule::GVA_Internal;
-
-  case ExternalLinkage:
-    switch (TSK) {
-    case TSK_Undeclared:
-    case TSK_ExplicitSpecialization:
-      return CodeGenModule::GVA_StrongExternal;
-
-    case TSK_ExplicitInstantiationDeclaration:
-      llvm_unreachable("Variable should not be instantiated");
-      // Fall through to treat this like any other instantiation.
-        
-    case TSK_ExplicitInstantiationDefinition:
-      return CodeGenModule::GVA_ExplicitTemplateInstantiation;
-
-    case TSK_ImplicitInstantiation:
-      return CodeGenModule::GVA_TemplateInstantiation;      
-    }
-  }
-
-  return CodeGenModule::GVA_StrongExternal;
-}
-
 CharUnits CodeGenModule::GetTargetTypeStoreSize(const llvm::Type *Ty) const {
     return CharUnits::fromQuantity(
       TheTargetData.getTypeStoreSizeInBits(Ty) / Context.getCharWidth());

diff --git a/test/CodeGenCXX/template-static-var-defer.cpp b/test/CodeGenCXX/template-static-var-defer.cpp
new file mode 100644 (file)
index 0000000..fe18c21
--- /dev/null
+++ b/test/CodeGenCXX/template-static-var-defer.cpp
@@ -0,0 +1,12 @@
+// RUN: %clang_cc1 %s -triple=x86_64-apple-darwin10 -emit-llvm -o - | not grep define
+// PR7415
+class X {
+  template <class Dummy> struct COMTypeInfo {
+    static const int kIID;
+  };
+  static const int& GetIID() {return COMTypeInfo<int>::kIID;}
+};
+template <class Dummy> const int X::COMTypeInfo<Dummy>::kIID = 10;
+
+
+