Re-commit "Don't inline dllimport functions referencing non-imported methods"

This re-commits r292522 with the addition that it also handles calls
through pointer to member functions without crashing.

llvm-svn: 292856

2 files changed, 20 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
index c9d9a35fb8a..f9866957a14 100644
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -1751,6 +1751,16 @@ namespace {
       SafeToInline = E->getConstructor()->hasAttr<DLLImportAttr>();
       return SafeToInline;
     }
+    bool VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
+      CXXMethodDecl *M = E->getMethodDecl();
+      if (!M) {
+        // Call through a pointer to member function. This is safe to inline.
+        SafeToInline = true;
+      } else {
+        SafeToInline = M->hasAttr<DLLImportAttr>();
+      }
+      return SafeToInline;
+    }
     bool VisitCXXDeleteExpr(CXXDeleteExpr *E) {
       SafeToInline = E->getOperatorDelete()->hasAttr<DLLImportAttr>();
       return SafeToInline;
diff --git a/clang/test/CodeGenCXX/dllimport.cpp b/clang/test/CodeGenCXX/dllimport.cpp
index 4ec14b72109..8e7ead9d1fe 100644
--- a/clang/test/CodeGenCXX/dllimport.cpp
+++ b/clang/test/CodeGenCXX/dllimport.cpp
@@ -26,6 +26,7 @@ struct ExplicitSpec_NotImported {};
 #define USEVARTYPE(type, var) type UNIQ(use)() { return var; }
 #define USEVAR(var) USEVARTYPE(int, var)
 #define USE(func) void UNIQ(use)() { func(); }
+#define USE1(func) void UNIQ(use)() { func(nullptr); }
 #define USEMEMFUNC(class, func) void (class::*UNIQ(use)())() { return &class::func; }
 #define USESTATICMEMFUNC(class, func) void (*UNIQ(use)())() { return &class::func; }
 #define USECLASS(class) void UNIQ(USE)() { class x; }
@@ -316,10 +317,13 @@ namespace ns { __declspec(dllimport) void externalFunc(); }
 USE(ns::externalFunc)
 
 // A dllimport function referencing non-imported vars or functions must not be available_externally.
+
 __declspec(dllimport) int ImportedVar;
 int NonImportedVar;
 __declspec(dllimport) int ImportedFunc();
 int NonImportedFunc();
+struct ClassWithNonImportedMethod { int f(); };
+
 __declspec(dllimport) inline int ReferencingImportedVar() { return ImportedVar; }
 // MO1-DAG: define available_externally dllimport i32 @"\01?ReferencingImportedVar@@YAHXZ"
 __declspec(dllimport) inline int ReferencingNonImportedVar() { return NonImportedVar; }
@@ -328,10 +332,16 @@ __declspec(dllimport) inline int ReferencingImportedFunc() { return ImportedFunc
 // MO1-DAG: define available_externally dllimport i32 @"\01?ReferencingImportedFunc@@YAHXZ"
 __declspec(dllimport) inline int ReferencingNonImportedFunc() { return NonImportedFunc(); }
 // MO1-DAG: declare dllimport i32 @"\01?ReferencingNonImportedFunc@@YAHXZ"()
+__declspec(dllimport) inline int ReferencingNonImportedMethod(ClassWithNonImportedMethod *x) { return x->f(); }
+// MO1-DAG: declare dllimport i32 @"\01?ReferencingNonImportedMethod
+__declspec(dllimport) inline int ReferencingClassMemberPtr(int (ClassWithNonImportedMethod::*p)(), ClassWithNonImportedMethod *x) { return (x->*p)(); }
+// MO1-DAG: define available_externally dllimport i32 @"\01?ReferencingClassMemberPtr@@YAHP8ClassWithNonImportedMethod@@AEHXZPAU1@@Z"
 USE(ReferencingImportedVar)
 USE(ReferencingNonImportedVar)
 USE(ReferencingImportedFunc)
 USE(ReferencingNonImportedFunc)
+USE1(ReferencingNonImportedMethod)
+void UNIQ(use)() { ReferencingClassMemberPtr(&ClassWithNonImportedMethod::f, nullptr); }
 // References to operator new and delete count too, despite not being DeclRefExprs.
 __declspec(dllimport) inline int *ReferencingNonImportedNew() { return new int[2]; }
 // MO1-DAG: declare dllimport i32* @"\01?ReferencingNonImportedNew@@YAPAHXZ"