r271361 - CodeGen: tweak CFString emission for COFF targets

[Saleem Abdulrasool via cfe-commits]

Author: compnerd
Date: Tue May 31 23:22:24 2016
New Revision: 271361

URL: http://llvm.org/viewvc/llvm-project?rev=271361&view=rev
Log:
CodeGen: tweak CFString emission for COFF targets

The `isa' member was previously not given the correct DLL Storage.  Ensure that
we give the `isa' constant `__CFConstantStringClassReference' the correct DLL
storage.  Default to dllimport unless an explicit specification gives it a
dllexport storage.

Added:
    cfe/trunk/test/CodeGen/cfstring-windows.c
Modified:
    cfe/trunk/lib/CodeGen/CodeGenModule.cpp

Modified: cfe/trunk/lib/CodeGen/CodeGenModule.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenModule.cpp?rev=271361&r1=271360&r2=271361&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenModule.cpp (original)
+++ cfe/trunk/lib/CodeGen/CodeGenModule.cpp Tue May 31 23:22:24 2016
@@ -3099,6 +3099,27 @@ CodeGenModule::GetAddrOfConstantCFString
     Ty = llvm::ArrayType::get(Ty, 0);
     llvm::Constant *GV =
         CreateRuntimeVariable(Ty, "__CFConstantStringClassReference");
+
+    if (getTarget().getTriple().isOSBinFormatCOFF()) {
+      IdentifierInfo &II = getContext().Idents.get(GV->getName());
+      TranslationUnitDecl *TUDecl = getContext().getTranslationUnitDecl();
+      DeclContext *DC = TranslationUnitDecl::castToDeclContext(TUDecl);
+      llvm::GlobalValue *CGV = cast<llvm::GlobalValue>(GV);
+
+      const VarDecl *VD = nullptr;
+      for (const auto &Result : DC->lookup(&II))
+        if ((VD = dyn_cast<VarDecl>(Result)))
+          break;
+
+      if (!VD || !VD->hasAttr<DLLExportAttr>()) {
+        CGV->setDLLStorageClass(llvm::GlobalValue::DLLImportStorageClass);
+        CGV->setLinkage(llvm::GlobalValue::ExternalLinkage);
+      } else {
+        CGV->setDLLStorageClass(llvm::GlobalValue::DLLExportStorageClass);
+        CGV->setLinkage(llvm::GlobalValue::ExternalLinkage);
+      }
+    }
+
     // Decay array -> ptr
     V = llvm::ConstantExpr::getGetElementPtr(Ty, GV, Zeros);
     CFConstantStringClassRef = V;

Added: cfe/trunk/test/CodeGen/cfstring-windows.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/cfstring-windows.c?rev=271361&view=auto
==============================================================================
--- cfe/trunk/test/CodeGen/cfstring-windows.c (added)
+++ cfe/trunk/test/CodeGen/cfstring-windows.c Tue May 31 23:22:24 2016
@@ -0,0 +1,40 @@
+// RUN: %clang_cc1 -triple thumbv7-windows -fdeclspec -DCF_BUILDING_CF -DDECL -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF-IN-CF-DECL
+// RUN: %clang_cc1 -triple thumbv7-windows -fdeclspec -DCF_BUILDING_CF -DDEFN -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF-IN-CF-DEFN
+// RUN: %clang_cc1 -triple thumbv7-windows -fdeclspec -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF
+// RUN: %clang_cc1 -triple thumbv7-windows -fdeclspec -DEXTERN -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF-EXTERN
+// RUN: %clang_cc1 -triple thumbv7-windows -fdeclspec -DEXTERN_DLLIMPORT -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF-EXTERN-DLLIMPORT
+// RUN: %clang_cc1 -triple thumbv7-windows -fdeclspec -DDLLIMPORT -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF-DLLIMPORT
+
+// RUN: %clang_cc1 -Os -triple thumbv7-windows -fdeclspec -DCF_BUILDING_CF -DDECL -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF-IN-CF-DECL
+// RUN: %clang_cc1 -Os -triple thumbv7-windows -fdeclspec -DCF_BUILDING_CF -DDEFN -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF-IN-CF-DEFN
+// RUN: %clang_cc1 -Os -triple thumbv7-windows -fdeclspec -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF
+// RUN: %clang_cc1 -Os -triple thumbv7-windows -fdeclspec -DEXTERN -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF-EXTERN
+// RUN: %clang_cc1 -Os -triple thumbv7-windows -fdeclspec -DEXTERN_DLLIMPORT -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF-EXTERN-DLLIMPORT
+// RUN: %clang_cc1 -Os -triple thumbv7-windows -fdeclspec -DDLLIMPORT -S -emit-llvm %s -o - | FileCheck %s -check-prefix CHECK-CF-DLLIMPORT
+
+#if defined(CF_BUILDING_CF)
+#if defined(DECL)
+extern __declspec(dllexport) long __CFConstantStringClassReference[];
+#elif defined(DEFN)
+__declspec(dllexport) long __CFConstantStringClassReference[32];
+#endif
+#else
+#if defined(EXTERN)
+extern long __CFConstantStringClassReference[];
+#elif defined(EXTERN_DLLIMPORT)
+extern __declspec(dllimport) long __CFConstantStringClassReference[];
+#elif defined(DLLIMPORT)
+__declspec(dllimport) long __CFConstantStringClassReference[];
+#endif
+#endif
+
+typedef struct __CFString *CFStringRef;
+const CFStringRef string = (CFStringRef)__builtin___CFStringMakeConstantString("string");
+
+// CHECK-CF-IN-CF-DECL: @__CFConstantStringClassReference = external dllexport global [0 x i32]
+// CHECK-CF-IN-CF-DEFN: @__CFConstantStringClassReference = common dllexport global [32 x i32]
+// CHECK-CF: @__CFConstantStringClassReference = external dllimport global [0 x i32]
+// CHECK-CF-EXTERN: @__CFConstantStringClassReference = external dllimport global [0 x i32]
+// CHECK-CF-EXTERN-DLLIMPORT: @__CFConstantStringClassReference = external dllimport global [0 x i32]
+// CHECK-CF-DLLIMPORT: @__CFConstantStringClassReference = external dllimport global [0 x i32]
+