[CodeView] Implement support for bitfields in LLVM
CodeView need to know the offset of the storage allocation for a
bitfield. Encode this via the "extraData" field in DIDerivedType and
introduced a new flag, DIFlagBitField, to indicate whether or not a
member is a bitfield.
This fixes PR28162.
Differential Revision: http://reviews.llvm.org/D21782
llvm-svn: 274200
diff --git a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
index e01ee09..a6bcf9e 100644
--- a/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -20,6 +20,7 @@
#include "llvm/DebugInfo/CodeView/TypeDumper.h"
#include "llvm/DebugInfo/CodeView/TypeIndex.h"
#include "llvm/DebugInfo/CodeView/TypeRecord.h"
+#include "llvm/IR/Constants.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCSectionCOFF.h"
#include "llvm/MC/MCSymbol.h"
@@ -1500,23 +1501,32 @@
for (ClassInfo::MemberInfo &MemberInfo : Info.Members) {
const DIDerivedType *Member = MemberInfo.MemberTypeNode;
TypeIndex MemberBaseType = getTypeIndex(Member->getBaseType());
+ StringRef MemberName = Member->getName();
+ MemberAccess Access =
+ translateAccessFlags(Ty->getTag(), Member->getFlags());
if (Member->isStaticMember()) {
- Fields.writeStaticDataMember(StaticDataMemberRecord(
- translateAccessFlags(Ty->getTag(), Member->getFlags()),
- MemberBaseType, Member->getName()));
+ Fields.writeStaticDataMember(
+ StaticDataMemberRecord(Access, MemberBaseType, MemberName));
MemberCount++;
continue;
}
- uint64_t OffsetInBytes = MemberInfo.BaseOffset;
-
- // FIXME: Handle bitfield type memeber.
- OffsetInBytes += Member->getOffsetInBits() / 8;
-
- Fields.writeDataMember(
- DataMemberRecord(translateAccessFlags(Ty->getTag(), Member->getFlags()),
- MemberBaseType, OffsetInBytes, Member->getName()));
+ // Data member.
+ uint64_t MemberOffsetInBits = Member->getOffsetInBits();
+ if (Member->isBitField()) {
+ uint64_t StartBitOffset = MemberOffsetInBits;
+ if (const auto *CI =
+ dyn_cast_or_null<ConstantInt>(Member->getStorageOffsetInBits())) {
+ MemberOffsetInBits = CI->getZExtValue();
+ }
+ StartBitOffset -= MemberOffsetInBits;
+ MemberBaseType = TypeTable.writeBitField(BitFieldRecord(
+ MemberBaseType, Member->getSizeInBits(), StartBitOffset));
+ }
+ uint64_t MemberOffsetInBytes = MemberOffsetInBits / 8;
+ Fields.writeDataMember(DataMemberRecord(Access, MemberBaseType,
+ MemberOffsetInBytes, MemberName));
MemberCount++;
}