r192664 - [ms-cxxabi] Fix assert in unspecified inheritance memptr emission

[Reid Kleckner]

Author: rnk
Date: Mon Oct 14 20:18:02 2013
New Revision: 192664

URL: http://llvm.org/viewvc/llvm-project?rev=192664&view=rev
Log:
[ms-cxxabi] Fix assert in unspecified inheritance memptr emission

If a class is using the unspecified inheritance model for member
pointers and later we find the class is defined to use single
inheritance, zero out the vbptr offset field of the member pointer when
it is formed.

Modified:
    cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp
    cfe/trunk/test/CodeGenCXX/microsoft-abi-member-pointers.cpp

Modified: cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp?rev=192664&r1=192663&r2=192664&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp (original)
+++ cfe/trunk/lib/CodeGen/MicrosoftCXXABI.cpp Mon Oct 14 20:18:02 2013
@@ -1156,8 +1156,10 @@ MicrosoftCXXABI::EmitFullMemberPointer(l
       CGM.IntTy, NonVirtualBaseAdjustment.getQuantity()));
 
   if (hasVBPtrOffsetField(Inheritance)) {
-    fields.push_back(llvm::ConstantInt::get(
-      CGM.IntTy, GetVBPtrOffsetFromBases(RD).getQuantity()));
+    CharUnits Offs = CharUnits::Zero();
+    if (RD->getNumVBases())
+      Offs = GetVBPtrOffsetFromBases(RD);
+    fields.push_back(llvm::ConstantInt::get(CGM.IntTy, Offs.getQuantity()));
   }
 
   // The rest of the fields are adjusted by conversions to a more derived class.

Modified: cfe/trunk/test/CodeGenCXX/microsoft-abi-member-pointers.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGenCXX/microsoft-abi-member-pointers.cpp?rev=192664&r1=192663&r2=192664&view=diff
==============================================================================
--- cfe/trunk/test/CodeGenCXX/microsoft-abi-member-pointers.cpp (original)
+++ cfe/trunk/test/CodeGenCXX/microsoft-abi-member-pointers.cpp Mon Oct 14 20:18:02 2013
@@ -42,6 +42,7 @@ struct NonZeroVBPtr : POD, Virtual {
 };
 
 struct Unspecified;
+struct UnspecSingle;
 
 // Check that we can lower the LLVM types and get the null initializers right.
 int Single     ::*s_d_memptr;
@@ -50,6 +51,7 @@ int Multiple   ::*m_d_memptr;
 int Virtual    ::*v_d_memptr;
 int NonZeroVBPtr::*n_d_memptr;
 int Unspecified::*u_d_memptr;
+int UnspecSingle::*us_d_memptr;
 // CHECK: @"\01?s_d_memptr@@3PQSingle@@HQ1@" = global i32 -1, align 4
 // CHECK: @"\01?p_d_memptr@@3PQPolymorphic@@HQ1@" = global i32 0, align 4
 // CHECK: @"\01?m_d_memptr@@3PQMultiple@@HQ1@" = global i32 -1, align 4
@@ -59,6 +61,8 @@ int Unspecified::*u_d_memptr;
 // CHECK:   { i32 0, i32 -1 }, align 4
 // CHECK: @"\01?u_d_memptr@@3PQUnspecified@@HQ1@" = global { i32, i32, i32 }
 // CHECK:   { i32 0, i32 0, i32 -1 }, align 4
+// CHECK: @"\01?us_d_memptr@@3PQUnspecSingle@@HQ1@" = global { i32, i32, i32 }
+// CHECK:   { i32 0, i32 0, i32 -1 }, align 4
 
 void (Single  ::*s_f_memptr)();
 void (Multiple::*m_f_memptr)();
@@ -73,12 +77,17 @@ struct Unspecified : Multiple, Virtual {
   int u;
 };
 
+struct UnspecSingle {
+  void foo();
+};
+
 // Test memptr emission in a constant expression.
 namespace Const {
 void (Single     ::*s_f_mp)() = &Single::foo;
 void (Multiple   ::*m_f_mp)() = &B2::foo;
 void (Virtual    ::*v_f_mp)() = &Virtual::foo;
 void (Unspecified::*u_f_mp)() = &Unspecified::foo;
+void (UnspecSingle::*us_f_mp)() = &UnspecSingle::foo;
 // CHECK: @"\01?s_f_mp at Const@@3P8Single@@AEXXZQ2@" =
 // CHECK:   global i8* bitcast ({{.*}} @"\01?foo at Single@@QAEXXZ" to i8*), align 4
 // CHECK: @"\01?m_f_mp at Const@@3P8Multiple@@AEXXZQ2@" =
@@ -87,6 +96,8 @@ void (Unspecified::*u_f_mp)() = &Unspeci
 // CHECK:   global { i8*, i32, i32 } { i8* bitcast ({{.*}} @"\01?foo at Virtual@@QAEXXZ" to i8*), i32 0, i32 0 }, align 4
 // CHECK: @"\01?u_f_mp at Const@@3P8Unspecified@@AEXXZQ2@" =
 // CHECK:   global { i8*, i32, i32, i32 } { i8* bitcast ({{.*}} @"\01?foo at Unspecified@@QAEXXZ" to i8*), i32 0, i32 12, i32 0 }, align 4
+// CHECK: @"\01?us_f_mp at Const@@3P8UnspecSingle@@AEXXZQ2@" =
+// CHECK:   global { i8*, i32, i32, i32 } { i8* bitcast ({{.*}} @"\01?foo at UnspecSingle@@QAEXXZ" to i8*), i32 0, i32 0, i32 0 }, align 4
 }
 
 namespace CastParam {