1 files changed, 14 insertions, 11 deletions
diff --git a/clang/lib/CodeGen/CGRecordLayoutBuilder.cpp b/clang/lib/CodeGen/CGRecordLayoutBuilder.cpp
index 4de64a32f2ac..4e5d1d3f16f6 100644
--- a/clang/lib/CodeGen/CGRecordLayoutBuilder.cpp
+++ b/clang/lib/CodeGen/CGRecordLayoutBuilder.cpp
@@ -385,7 +385,8 @@ CGRecordLowering::accumulateBitFields(RecordDecl::field_iterator Field,
         Run = FieldEnd;
         continue;
       }
-      llvm::Type *Type = Types.ConvertTypeForMem(Field->getType());
+      llvm::Type *Type =
+          Types.ConvertTypeForMem(Field->getType(), /*ForBitFields=*/true);
       // If we don't have a run yet, or don't live within the previous run's
       // allocated storage then we allocate some storage and start a new run.
       if (Run == FieldEnd || BitOffset >= Tail) {
@@ -405,15 +406,17 @@ CGRecordLowering::accumulateBitFields(RecordDecl::field_iterator Field,
     return;
   }
 
-  // Check if OffsetInRecord is better as a single field run. When OffsetInRecord
-  // has legal integer width, and its bitfield offset is naturally aligned, it
-  // is better to make the bitfield a separate storage component so as it can be
-  // accessed directly with lower cost.
+  // Check if OffsetInRecord (the size in bits of the current run) is better
+  // as a single field run. When OffsetInRecord has legal integer width, and
+  // its bitfield offset is naturally aligned, it is better to make the
+  // bitfield a separate storage component so as it can be accessed directly
+  // with lower cost.
   auto IsBetterAsSingleFieldRun = [&](uint64_t OffsetInRecord,
                                       uint64_t StartBitOffset) {
     if (!Types.getCodeGenOpts().FineGrainedBitfieldAccesses)
       return false;
-    if (!DataLayout.isLegalInteger(OffsetInRecord))
+    if (OffsetInRecord < 8 || !llvm::isPowerOf2_64(OffsetInRecord) ||
+        !DataLayout.fitsInLegalInteger(OffsetInRecord))
       return false;
     // Make sure StartBitOffset is natually aligned if it is treated as an
     // IType integer.
@@ -729,8 +732,8 @@ CGBitFieldInfo CGBitFieldInfo::MakeInfo(CodeGenTypes &Types,
   return CGBitFieldInfo(Offset, Size, IsSigned, StorageSize, StorageOffset);
 }
 
-CGRecordLayout *CodeGenTypes::ComputeRecordLayout(const RecordDecl *D,
-                                                  llvm::StructType *Ty) {
+std::unique_ptr<CGRecordLayout>
+CodeGenTypes::ComputeRecordLayout(const RecordDecl *D, llvm::StructType *Ty) {
   CGRecordLowering Builder(*this, D, /*Packed=*/false);
 
   Builder.lower(/*NonVirtualBaseType=*/false);
@@ -757,9 +760,9 @@ CGRecordLayout *CodeGenTypes::ComputeRecordLayout(const RecordDecl *D,
   // but we may need to recursively layout D while laying D out as a base type.
   Ty->setBody(Builder.FieldTypes, Builder.Packed);
 
-  CGRecordLayout *RL =
-    new CGRecordLayout(Ty, BaseTy, Builder.IsZeroInitializable,
-                        Builder.IsZeroInitializableAsBase);
+  auto RL = std::make_unique<CGRecordLayout>(
+      Ty, BaseTy, (bool)Builder.IsZeroInitializable,
+      (bool)Builder.IsZeroInitializableAsBase);
 
   RL->NonVirtualBases.swap(Builder.NonVirtualBases);
   RL->CompleteObjectVirtualBases.swap(Builder.VirtualBases);