[PowerPC ABI] Bug 21398 - Consider C++ base classes in HA classification

As discussed in bug 21398, PowerPC ABI code needs to consider C++ base
classes when classifying a class as homogeneous aggregate (or not) for
ABI purposes.

llvm-svn: 220852

1 files changed, 16 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/TargetInfo.cpp b/clang/lib/CodeGen/TargetInfo.cpp
index ea62e4e409d..4fcfc79abd7 100644
--- a/clang/lib/CodeGen/TargetInfo.cpp
+++ b/clang/lib/CodeGen/TargetInfo.cpp
@@ -3208,6 +3208,22 @@ PPC64_SVR4_ABIInfo::isHomogeneousAggregate(QualType Ty, const Type *&Base,
       return false;
 
     Members = 0;
+
+    // If this is a C++ record, check the bases first.
+    if (const CXXRecordDecl *CXXRD = dyn_cast<CXXRecordDecl>(RD)) {
+      for (const auto &I : CXXRD->bases()) {
+        // Ignore empty records.
+        if (isEmptyRecord(getContext(), I.getType(), true))
+          continue;
+
+        uint64_t FldMembers;
+        if (!isHomogeneousAggregate(I.getType(), Base, FldMembers))
+          return false;
+
+        Members += FldMembers;
+      }
+    }
+
     for (const auto *FD : RD->fields()) {
       // Ignore (non-zero arrays of) empty records.
       QualType FT = FD->getType();