[MS ABI] Fix the preferred alignment of member pointers

Member pointers in the MS ABI have different alignment depending on
whether they were created on the stack or live in a record.

llvm-svn: 235681

2 files changed, 7 insertions, 3 deletions

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index 4d6a51bf192..0fc9a4e96b0 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -1797,11 +1797,16 @@ unsigned ASTContext::getPreferredTypeAlign(const Type *T) const {
   TypeInfo TI = getTypeInfo(T);
   unsigned ABIAlign = TI.Align;
 
+  T = T->getBaseElementTypeUnsafe();
+
+  // The preferred alignment of member pointers is that of a pointer.
+  if (T->isMemberPointerType())
+    return getPreferredTypeAlign(getPointerDiffType().getTypePtr());
+
   if (Target->getTriple().getArch() == llvm::Triple::xcore)
     return ABIAlign;  // Never overalign on XCore.
 
   // Double and long long should be naturally aligned if possible.
-  T = T->getBaseElementTypeUnsafe();
   if (const ComplexType *CT = T->getAs<ComplexType>())
     T = CT->getElementType().getTypePtr();
   if (const EnumType *ET = T->getAs<EnumType>())
diff --git a/clang/lib/CodeGen/CGCall.cpp b/clang/lib/CodeGen/CGCall.cpp
index d82c58fb7e1..2e180c97eee 100644
--- a/clang/lib/CodeGen/CGCall.cpp
+++ b/clang/lib/CodeGen/CGCall.cpp
@@ -1813,8 +1813,7 @@ void CodeGenFunction::EmitFunctionProlog(const CGFunctionInfo &FI,
         ArgVals.push_back(ValueAndIsPtr(V, HavePointer));
       } else {
         // Load scalar value from indirect argument.
-        CharUnits Alignment = getContext().getTypeAlignInChars(Ty);
-        V = EmitLoadOfScalar(V, false, Alignment.getQuantity(), Ty,
+        V = EmitLoadOfScalar(V, false, ArgI.getIndirectAlign(), Ty,
                              Arg->getLocStart());
 
         if (isPromoted)