PR14759: Improve/correct support for debug info for C++ member pointers.

Using added LLVM functionality in r171698. This works in GDB for member
variable pointers but not member function pointers. See the LLVM commit and
GDB bug 14998 for details.

Un-xfailing cases in the GDB 7.5 test suite will follow.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@171699 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/CGDebugInfo.cpp b/lib/CodeGen/CGDebugInfo.cpp
index bc715f4d6d23a711262de4b8300e607ab00d74bb..4ebce65ff42731640701daa67501bd575ea6894e 100644 (file)
--- a/lib/CodeGen/CGDebugInfo.cpp
+++ b/lib/CodeGen/CGDebugInfo.cpp
@@ -1589,38 +1589,8 @@ llvm::DIType CGDebugInfo::CreateType(const RValueReferenceType *Ty,
 
 llvm::DIType CGDebugInfo::CreateType(const MemberPointerType *Ty, 
                                      llvm::DIFile U) {
-  QualType PointerDiffTy = CGM.getContext().getPointerDiffType();
-  llvm::DIType PointerDiffDITy = getOrCreateType(PointerDiffTy, U);
-  
-  if (!Ty->getPointeeType()->isFunctionType()) {
-    // We have a data member pointer type.
-    return PointerDiffDITy;
-  }
-  
-  // We have a member function pointer type. Treat it as a struct with two
-  // ptrdiff_t members.
-  std::pair<uint64_t, unsigned> Info = CGM.getContext().getTypeInfo(Ty);
-
-  uint64_t FieldOffset = 0;
-  llvm::Value *ElementTypes[2];
-  
-  // FIXME: This should be a DW_TAG_pointer_to_member type.
-  ElementTypes[0] =
-    DBuilder.createMemberType(U, "ptr", U, 0,
-                              Info.first, Info.second, FieldOffset, 0,
-                              PointerDiffDITy);
-  FieldOffset += Info.first;
-  
-  ElementTypes[1] =
-    DBuilder.createMemberType(U, "ptr", U, 0,
-                              Info.first, Info.second, FieldOffset, 0,
-                              PointerDiffDITy);
-  
-  llvm::DIArray Elements = DBuilder.getOrCreateArray(ElementTypes);
-
-  return DBuilder.createStructType(U, StringRef("test"), 
-                                   U, 0, FieldOffset, 
-                                   0, 0, Elements);
+  return DBuilder.createMemberPointerType(CreatePointeeType(Ty->getPointeeType(), U),
+                                    getOrCreateType(QualType(Ty->getClass(), 0), U));
 }
 
 llvm::DIType CGDebugInfo::CreateType(const AtomicType *Ty, 

diff --git a/test/CodeGenCXX/debug-info-method.cpp b/test/CodeGenCXX/debug-info-method.cpp
index dfd397987fba007db24539ac9e972291f2d8ce1e..e9aa34a4a09ffdbce18b30b4f1a33dd47efe0eae 100644 (file)
--- a/test/CodeGenCXX/debug-info-method.cpp
+++ b/test/CodeGenCXX/debug-info-method.cpp
@@ -1,5 +1,7 @@
 // RUN: %clang_cc1 -emit-llvm -std=c++11 -g %s -o - | FileCheck %s
 // CHECK: metadata !"_ZN1A3fooEiS_3$_0", {{.*}} [protected]
+// CHECK: DW_TAG_ptr_to_member_type
+// CHECK: DW_TAG_ptr_to_member_type
 // CHECK: ""{{.*}}DW_TAG_arg_variable
 // CHECK: ""{{.*}}DW_TAG_arg_variable
 // CHECK: ""{{.*}}DW_TAG_arg_variable
@@ -17,3 +19,6 @@ void A::foo(int, A, decltype(u)) {
 }
 
 A a;
+
+int A::*x = 0;
+int (A::*y)(int) = 0;