r185018 - Rewrite record layout for ms_struct structs.
Eli Friedman
eli.friedman at gmail.com
Wed Jun 26 13:50:35 PDT 2013
Author: efriedma
Date: Wed Jun 26 15:50:34 2013
New Revision: 185018
URL: http://llvm.org/viewvc/llvm-project?rev=185018&view=rev
Log:
Rewrite record layout for ms_struct structs.
The old implementation of ms_struct in RecordLayoutBuilder was a
complete mess: it depended on complicated conditionals which didn't
really reflect the underlying logic, and placed a burden on users of
the resulting RecordLayout. This commit rips out almost all of the
old code, and replaces it with simple checks in
RecordLayoutBuilder::LayoutBitField.
This commit also fixes <rdar://problem/14252115>, a bug where class
inheritance would cause us to lay out bitfields incorrectly.
Added:
cfe/trunk/test/SemaCXX/ms_struct.cpp
Modified:
cfe/trunk/include/clang/AST/ASTContext.h
cfe/trunk/lib/AST/ASTContext.cpp
cfe/trunk/lib/AST/Decl.cpp
cfe/trunk/lib/AST/RecordLayoutBuilder.cpp
cfe/trunk/lib/CodeGen/CGDebugInfo.cpp
cfe/trunk/lib/CodeGen/CGExprConstant.cpp
cfe/trunk/lib/CodeGen/CGRecordLayoutBuilder.cpp
cfe/trunk/lib/CodeGen/CodeGenTBAA.cpp
cfe/trunk/test/CodeGen/tbaa-struct.cpp
cfe/trunk/test/CodeGen/tbaa.cpp
Modified: cfe/trunk/include/clang/AST/ASTContext.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/AST/ASTContext.h?rev=185018&r1=185017&r2=185018&view=diff
==============================================================================
--- cfe/trunk/include/clang/AST/ASTContext.h (original)
+++ cfe/trunk/include/clang/AST/ASTContext.h Wed Jun 26 15:50:34 2013
@@ -634,31 +634,6 @@ public:
void setInstantiatedFromUnnamedFieldDecl(FieldDecl *Inst, FieldDecl *Tmpl);
- /// \brief Return \c true if \p FD is a zero-length bitfield which follows
- /// the non-bitfield \p LastFD.
- bool ZeroBitfieldFollowsNonBitfield(const FieldDecl *FD,
- const FieldDecl *LastFD) const;
-
- /// \brief Return \c true if \p FD is a zero-length bitfield which follows
- /// the bitfield \p LastFD.
- bool ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
- const FieldDecl *LastFD) const;
-
- /// \brief Return \c true if \p FD is a bitfield which follows the bitfield
- /// \p LastFD.
- bool BitfieldFollowsBitfield(const FieldDecl *FD,
- const FieldDecl *LastFD) const;
-
- /// \brief Return \c true if \p FD is not a bitfield which follows the
- /// bitfield \p LastFD.
- bool NonBitfieldFollowsBitfield(const FieldDecl *FD,
- const FieldDecl *LastFD) const;
-
- /// \brief Return \c true if \p FD is a bitfield which follows the
- /// non-bitfield \p LastFD.
- bool BitfieldFollowsNonBitfield(const FieldDecl *FD,
- const FieldDecl *LastFD) const;
-
// Access to the set of methods overridden by the given C++ method.
typedef CXXMethodVector::const_iterator overridden_cxx_method_iterator;
overridden_cxx_method_iterator
Modified: cfe/trunk/lib/AST/ASTContext.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ASTContext.cpp?rev=185018&r1=185017&r2=185018&view=diff
==============================================================================
--- cfe/trunk/lib/AST/ASTContext.cpp (original)
+++ cfe/trunk/lib/AST/ASTContext.cpp Wed Jun 26 15:50:34 2013
@@ -1132,38 +1132,6 @@ void ASTContext::setInstantiatedFromUnna
InstantiatedFromUnnamedFieldDecl[Inst] = Tmpl;
}
-bool ASTContext::ZeroBitfieldFollowsNonBitfield(const FieldDecl *FD,
- const FieldDecl *LastFD) const {
- return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
- FD->getBitWidthValue(*this) == 0);
-}
-
-bool ASTContext::ZeroBitfieldFollowsBitfield(const FieldDecl *FD,
- const FieldDecl *LastFD) const {
- return (FD->isBitField() && LastFD && LastFD->isBitField() &&
- FD->getBitWidthValue(*this) == 0 &&
- LastFD->getBitWidthValue(*this) != 0);
-}
-
-bool ASTContext::BitfieldFollowsBitfield(const FieldDecl *FD,
- const FieldDecl *LastFD) const {
- return (FD->isBitField() && LastFD && LastFD->isBitField() &&
- FD->getBitWidthValue(*this) &&
- LastFD->getBitWidthValue(*this));
-}
-
-bool ASTContext::NonBitfieldFollowsBitfield(const FieldDecl *FD,
- const FieldDecl *LastFD) const {
- return (!FD->isBitField() && LastFD && LastFD->isBitField() &&
- LastFD->getBitWidthValue(*this));
-}
-
-bool ASTContext::BitfieldFollowsNonBitfield(const FieldDecl *FD,
- const FieldDecl *LastFD) const {
- return (FD->isBitField() && LastFD && !LastFD->isBitField() &&
- FD->getBitWidthValue(*this));
-}
-
ASTContext::overridden_cxx_method_iterator
ASTContext::overridden_methods_begin(const CXXMethodDecl *Method) const {
llvm::DenseMap<const CXXMethodDecl *, CXXMethodVector>::const_iterator Pos
Modified: cfe/trunk/lib/AST/Decl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/Decl.cpp?rev=185018&r1=185017&r2=185018&view=diff
==============================================================================
--- cfe/trunk/lib/AST/Decl.cpp (original)
+++ cfe/trunk/lib/AST/Decl.cpp Wed Jun 26 15:50:34 2013
@@ -2917,23 +2917,11 @@ unsigned FieldDecl::getFieldIndex() cons
unsigned Index = 0;
const RecordDecl *RD = getParent();
- const FieldDecl *LastFD = 0;
- bool IsMsStruct = RD->isMsStruct(getASTContext());
for (RecordDecl::field_iterator I = RD->field_begin(), E = RD->field_end();
- I != E; ++I, ++Index) {
+ I != E; ++I, ++Index)
I->CachedFieldIndex = Index + 1;
- if (IsMsStruct) {
- // Zero-length bitfields following non-bitfield members are ignored.
- if (getASTContext().ZeroBitfieldFollowsNonBitfield(*I, LastFD)) {
- --Index;
- continue;
- }
- LastFD = *I;
- }
- }
-
assert(CachedFieldIndex && "failed to find field in parent");
return CachedFieldIndex - 1;
}
Modified: cfe/trunk/lib/AST/RecordLayoutBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/RecordLayoutBuilder.cpp?rev=185018&r1=185017&r2=185018&view=diff
==============================================================================
--- cfe/trunk/lib/AST/RecordLayoutBuilder.cpp (original)
+++ cfe/trunk/lib/AST/RecordLayoutBuilder.cpp Wed Jun 26 15:50:34 2013
@@ -573,10 +573,14 @@ protected:
unsigned IsMsStruct : 1;
- /// UnfilledBitsInLastByte - If the last field laid out was a bitfield,
- /// this contains the number of bits in the last byte that can be used for
- /// an adjacent bitfield if necessary.
- unsigned char UnfilledBitsInLastByte;
+ /// UnfilledBitsInLastUnit - If the last field laid out was a bitfield,
+ /// this contains the number of bits in the last unit that can be used for
+ /// an adjacent bitfield if necessary. The unit in question is usually
+ /// a byte, but larger units are used if IsMsStruct.
+ unsigned char UnfilledBitsInLastUnit;
+ /// LastBitfieldTypeSize - If IsMsStruct, represents the size of the type
+ /// of the previous field if it was a bitfield.
+ unsigned char LastBitfieldTypeSize;
/// MaxFieldAlignment - The maximum allowed field alignment. This is set by
/// #pragma pack.
@@ -646,7 +650,8 @@ protected:
Alignment(CharUnits::One()), UnpackedAlignment(CharUnits::One()),
ExternalLayout(false), InferAlignment(false),
Packed(false), IsUnion(false), IsMac68kAlign(false), IsMsStruct(false),
- UnfilledBitsInLastByte(0), MaxFieldAlignment(CharUnits::Zero()),
+ UnfilledBitsInLastUnit(0), LastBitfieldTypeSize(0),
+ MaxFieldAlignment(CharUnits::Zero()),
DataSize(0), NonVirtualSize(CharUnits::Zero()),
NonVirtualAlignment(CharUnits::One()),
ZeroLengthBitfield(0), PrimaryBase(0),
@@ -1728,123 +1733,16 @@ void RecordLayoutBuilder::Layout(const O
void RecordLayoutBuilder::LayoutFields(const RecordDecl *D) {
// Layout each field, for now, just sequentially, respecting alignment. In
// the future, this will need to be tweakable by targets.
- const FieldDecl *LastFD = 0;
ZeroLengthBitfield = 0;
- unsigned RemainingInAlignment = 0;
for (RecordDecl::field_iterator Field = D->field_begin(),
FieldEnd = D->field_end(); Field != FieldEnd; ++Field) {
- if (IsMsStruct) {
- FieldDecl *FD = *Field;
- if (Context.ZeroBitfieldFollowsBitfield(FD, LastFD))
- ZeroLengthBitfield = FD;
- // Zero-length bitfields following non-bitfield members are
- // ignored:
- else if (Context.ZeroBitfieldFollowsNonBitfield(FD, LastFD))
- continue;
- // FIXME. streamline these conditions into a simple one.
- else if (Context.BitfieldFollowsBitfield(FD, LastFD) ||
- Context.BitfieldFollowsNonBitfield(FD, LastFD) ||
- Context.NonBitfieldFollowsBitfield(FD, LastFD)) {
- // 1) Adjacent bit fields are packed into the same 1-, 2-, or
- // 4-byte allocation unit if the integral types are the same
- // size and if the next bit field fits into the current
- // allocation unit without crossing the boundary imposed by the
- // common alignment requirements of the bit fields.
- // 2) Establish a new alignment for a bitfield following
- // a non-bitfield if size of their types differ.
- // 3) Establish a new alignment for a non-bitfield following
- // a bitfield if size of their types differ.
- std::pair<uint64_t, unsigned> FieldInfo =
- Context.getTypeInfo(FD->getType());
- uint64_t TypeSize = FieldInfo.first;
- unsigned FieldAlign = FieldInfo.second;
- // This check is needed for 'long long' in -m32 mode.
- if (TypeSize > FieldAlign &&
- (Context.hasSameType(FD->getType(),
- Context.UnsignedLongLongTy)
- ||Context.hasSameType(FD->getType(),
- Context.LongLongTy)))
- FieldAlign = TypeSize;
- FieldInfo = Context.getTypeInfo(LastFD->getType());
- uint64_t TypeSizeLastFD = FieldInfo.first;
- unsigned FieldAlignLastFD = FieldInfo.second;
- // This check is needed for 'long long' in -m32 mode.
- if (TypeSizeLastFD > FieldAlignLastFD &&
- (Context.hasSameType(LastFD->getType(),
- Context.UnsignedLongLongTy)
- || Context.hasSameType(LastFD->getType(),
- Context.LongLongTy)))
- FieldAlignLastFD = TypeSizeLastFD;
-
- if (TypeSizeLastFD != TypeSize) {
- if (RemainingInAlignment &&
- LastFD && LastFD->isBitField() &&
- LastFD->getBitWidthValue(Context)) {
- // If previous field was a bitfield with some remaining unfilled
- // bits, pad the field so current field starts on its type boundary.
- uint64_t FieldOffset =
- getDataSizeInBits() - UnfilledBitsInLastByte;
- uint64_t NewSizeInBits = RemainingInAlignment + FieldOffset;
- setDataSize(llvm::RoundUpToAlignment(NewSizeInBits,
- Context.getTargetInfo().getCharAlign()));
- setSize(std::max(getSizeInBits(), getDataSizeInBits()));
- RemainingInAlignment = 0;
- }
-
- uint64_t UnpaddedFieldOffset =
- getDataSizeInBits() - UnfilledBitsInLastByte;
- FieldAlign = std::max(FieldAlign, FieldAlignLastFD);
-
- // The maximum field alignment overrides the aligned attribute.
- if (!MaxFieldAlignment.isZero()) {
- unsigned MaxFieldAlignmentInBits =
- Context.toBits(MaxFieldAlignment);
- FieldAlign = std::min(FieldAlign, MaxFieldAlignmentInBits);
- }
-
- uint64_t NewSizeInBits =
- llvm::RoundUpToAlignment(UnpaddedFieldOffset, FieldAlign);
- setDataSize(llvm::RoundUpToAlignment(NewSizeInBits,
- Context.getTargetInfo().getCharAlign()));
- UnfilledBitsInLastByte = getDataSizeInBits() - NewSizeInBits;
- setSize(std::max(getSizeInBits(), getDataSizeInBits()));
- }
- if (FD->isBitField()) {
- uint64_t FieldSize = FD->getBitWidthValue(Context);
- assert (FieldSize > 0 && "LayoutFields - ms_struct layout");
- if (RemainingInAlignment < FieldSize)
- RemainingInAlignment = TypeSize - FieldSize;
- else
- RemainingInAlignment -= FieldSize;
- }
- }
- else if (FD->isBitField()) {
- uint64_t FieldSize = FD->getBitWidthValue(Context);
- std::pair<uint64_t, unsigned> FieldInfo =
- Context.getTypeInfo(FD->getType());
- uint64_t TypeSize = FieldInfo.first;
- RemainingInAlignment = TypeSize - FieldSize;
- }
- LastFD = FD;
- }
- else if (!Context.getTargetInfo().useBitFieldTypeAlignment() &&
- Context.getTargetInfo().useZeroLengthBitfieldAlignment()) {
+ if (!Context.getTargetInfo().useBitFieldTypeAlignment() &&
+ Context.getTargetInfo().useZeroLengthBitfieldAlignment()) {
if (Field->isBitField() && Field->getBitWidthValue(Context) == 0)
ZeroLengthBitfield = *Field;
}
LayoutField(*Field);
}
- if (IsMsStruct && RemainingInAlignment &&
- LastFD && LastFD->isBitField() && LastFD->getBitWidthValue(Context)) {
- // If we ended a bitfield before the full length of the type then
- // pad the struct out to the full length of the last type.
- uint64_t FieldOffset =
- getDataSizeInBits() - UnfilledBitsInLastByte;
- uint64_t NewSizeInBits = RemainingInAlignment + FieldOffset;
- setDataSize(llvm::RoundUpToAlignment(NewSizeInBits,
- Context.getTargetInfo().getCharAlign()));
- setSize(std::max(getSizeInBits(), getDataSizeInBits()));
- }
}
void RecordLayoutBuilder::LayoutWideBitField(uint64_t FieldSize,
@@ -1878,10 +1776,11 @@ void RecordLayoutBuilder::LayoutWideBitF
CharUnits TypeAlign = Context.getTypeAlignInChars(Type);
// We're not going to use any of the unfilled bits in the last byte.
- UnfilledBitsInLastByte = 0;
+ UnfilledBitsInLastUnit = 0;
+ LastBitfieldTypeSize = 0;
uint64_t FieldOffset;
- uint64_t UnpaddedFieldOffset = getDataSizeInBits() - UnfilledBitsInLastByte;
+ uint64_t UnpaddedFieldOffset = getDataSizeInBits() - UnfilledBitsInLastUnit;
if (IsUnion) {
setDataSize(std::max(getDataSizeInBits(), FieldSize));
@@ -1896,7 +1795,7 @@ void RecordLayoutBuilder::LayoutWideBitF
setDataSize(llvm::RoundUpToAlignment(NewSizeInBits,
Context.getTargetInfo().getCharAlign()));
- UnfilledBitsInLastByte = getDataSizeInBits() - NewSizeInBits;
+ UnfilledBitsInLastUnit = getDataSizeInBits() - NewSizeInBits;
}
// Place this field at the current location.
@@ -1914,47 +1813,37 @@ void RecordLayoutBuilder::LayoutWideBitF
void RecordLayoutBuilder::LayoutBitField(const FieldDecl *D) {
bool FieldPacked = Packed || D->hasAttr<PackedAttr>();
- uint64_t UnpaddedFieldOffset = getDataSizeInBits() - UnfilledBitsInLastByte;
- uint64_t FieldOffset = IsUnion ? 0 : UnpaddedFieldOffset;
uint64_t FieldSize = D->getBitWidthValue(Context);
-
std::pair<uint64_t, unsigned> FieldInfo = Context.getTypeInfo(D->getType());
uint64_t TypeSize = FieldInfo.first;
unsigned FieldAlign = FieldInfo.second;
-
- // This check is needed for 'long long' in -m32 mode.
- if (IsMsStruct && (TypeSize > FieldAlign) &&
- (Context.hasSameType(D->getType(),
- Context.UnsignedLongLongTy)
- || Context.hasSameType(D->getType(), Context.LongLongTy)))
+
+ if (IsMsStruct) {
+ // The field alignment for integer types in ms_struct structs is
+ // always the size.
FieldAlign = TypeSize;
+ // Ignore zero-length bitfields after non-bitfields in ms_struct structs.
+ if (!FieldSize && !LastBitfieldTypeSize)
+ FieldAlign = 1;
+ // If a bitfield is followed by a bitfield of a different size, don't
+ // pack the bits together in ms_struct structs.
+ if (LastBitfieldTypeSize != TypeSize) {
+ UnfilledBitsInLastUnit = 0;
+ LastBitfieldTypeSize = 0;
+ }
+ }
+
+ uint64_t UnpaddedFieldOffset = getDataSizeInBits() - UnfilledBitsInLastUnit;
+ uint64_t FieldOffset = IsUnion ? 0 : UnpaddedFieldOffset;
if (ZeroLengthBitfield) {
- std::pair<uint64_t, unsigned> FieldInfo;
- unsigned ZeroLengthBitfieldAlignment;
- if (IsMsStruct) {
- // If a zero-length bitfield is inserted after a bitfield,
- // and the alignment of the zero-length bitfield is
- // greater than the member that follows it, `bar', `bar'
- // will be aligned as the type of the zero-length bitfield.
- if (ZeroLengthBitfield != D) {
- FieldInfo = Context.getTypeInfo(ZeroLengthBitfield->getType());
- ZeroLengthBitfieldAlignment = FieldInfo.second;
- // Ignore alignment of subsequent zero-length bitfields.
- if ((ZeroLengthBitfieldAlignment > FieldAlign) || (FieldSize == 0))
- FieldAlign = ZeroLengthBitfieldAlignment;
- if (FieldSize)
- ZeroLengthBitfield = 0;
- }
- } else {
- // The alignment of a zero-length bitfield affects the alignment
- // of the next member. The alignment is the max of the zero
- // length bitfield's alignment and a target specific fixed value.
- unsigned ZeroLengthBitfieldBoundary =
- Context.getTargetInfo().getZeroLengthBitfieldBoundary();
- if (ZeroLengthBitfieldBoundary > FieldAlign)
- FieldAlign = ZeroLengthBitfieldBoundary;
- }
+ // The alignment of a zero-length bitfield affects the alignment
+ // of the next member. The alignment is the max of the zero
+ // length bitfield's alignment and a target specific fixed value.
+ unsigned ZeroLengthBitfieldBoundary =
+ Context.getTargetInfo().getZeroLengthBitfieldBoundary();
+ if (ZeroLengthBitfieldBoundary > FieldAlign)
+ FieldAlign = ZeroLengthBitfieldBoundary;
}
if (FieldSize > TypeSize) {
@@ -1982,6 +1871,13 @@ void RecordLayoutBuilder::LayoutBitField
UnpackedFieldAlign = std::min(UnpackedFieldAlign, MaxFieldAlignmentInBits);
}
+ // ms_struct bitfields always have to start at a round alignment.
+ if (IsMsStruct && !LastBitfieldTypeSize) {
+ FieldOffset = llvm::RoundUpToAlignment(FieldOffset, FieldAlign);
+ UnpackedFieldOffset = llvm::RoundUpToAlignment(UnpackedFieldOffset,
+ UnpackedFieldAlign);
+ }
+
// Check if we need to add padding to give the field the correct alignment.
if (FieldSize == 0 ||
(MaxFieldAlignment.isZero() &&
@@ -1996,11 +1892,12 @@ void RecordLayoutBuilder::LayoutBitField
// Padding members don't affect overall alignment, unless zero length bitfield
// alignment is enabled.
- if (!D->getIdentifier() && !Context.getTargetInfo().useZeroLengthBitfieldAlignment())
+ if (!D->getIdentifier() &&
+ !Context.getTargetInfo().useZeroLengthBitfieldAlignment() &&
+ !IsMsStruct)
FieldAlign = UnpackedFieldAlign = 1;
- if (!IsMsStruct)
- ZeroLengthBitfield = 0;
+ ZeroLengthBitfield = 0;
if (ExternalLayout)
FieldOffset = updateExternalFieldOffset(D, FieldOffset);
@@ -2017,11 +1914,29 @@ void RecordLayoutBuilder::LayoutBitField
// FIXME: I think FieldSize should be TypeSize here.
setDataSize(std::max(getDataSizeInBits(), FieldSize));
} else {
- uint64_t NewSizeInBits = FieldOffset + FieldSize;
-
- setDataSize(llvm::RoundUpToAlignment(NewSizeInBits,
- Context.getTargetInfo().getCharAlign()));
- UnfilledBitsInLastByte = getDataSizeInBits() - NewSizeInBits;
+ if (IsMsStruct && FieldSize) {
+ // Under ms_struct, a bitfield always takes up space equal to the size
+ // of the type. We can't just change the alignment computation on the
+ // other codepath because of the way this interacts with #pragma pack:
+ // in a packed struct, we need to allocate misaligned space in the
+ // struct to hold the bitfield.
+ if (!UnfilledBitsInLastUnit) {
+ setDataSize(FieldOffset + TypeSize);
+ UnfilledBitsInLastUnit = TypeSize - FieldSize;
+ } else if (UnfilledBitsInLastUnit < FieldSize) {
+ setDataSize(getDataSizeInBits() + TypeSize);
+ UnfilledBitsInLastUnit = TypeSize - FieldSize;
+ } else {
+ UnfilledBitsInLastUnit -= FieldSize;
+ }
+ LastBitfieldTypeSize = TypeSize;
+ } else {
+ uint64_t NewSizeInBits = FieldOffset + FieldSize;
+ uint64_t BitfieldAlignment = Context.getTargetInfo().getCharAlign();
+ setDataSize(llvm::RoundUpToAlignment(NewSizeInBits, BitfieldAlignment));
+ UnfilledBitsInLastUnit = getDataSizeInBits() - NewSizeInBits;
+ LastBitfieldTypeSize = 0;
+ }
}
// Update the size.
@@ -2038,10 +1953,11 @@ void RecordLayoutBuilder::LayoutField(co
return;
}
- uint64_t UnpaddedFieldOffset = getDataSizeInBits() - UnfilledBitsInLastByte;
+ uint64_t UnpaddedFieldOffset = getDataSizeInBits() - UnfilledBitsInLastUnit;
// Reset the unfilled bits.
- UnfilledBitsInLastByte = 0;
+ UnfilledBitsInLastUnit = 0;
+ LastBitfieldTypeSize = 0;
bool FieldPacked = Packed || D->hasAttr<PackedAttr>();
CharUnits FieldOffset =
@@ -2189,7 +2105,7 @@ void RecordLayoutBuilder::FinishLayout(c
// Finally, round the size of the record up to the alignment of the
// record itself.
- uint64_t UnpaddedSize = getSizeInBits() - UnfilledBitsInLastByte;
+ uint64_t UnpaddedSize = getSizeInBits() - UnfilledBitsInLastUnit;
uint64_t UnpackedSizeInBits =
llvm::RoundUpToAlignment(getSizeInBits(),
Context.toBits(UnpackedAlignment));
Modified: cfe/trunk/lib/CodeGen/CGDebugInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDebugInfo.cpp?rev=185018&r1=185017&r2=185018&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGDebugInfo.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGDebugInfo.cpp Wed Jun 26 15:50:34 2013
@@ -915,10 +915,6 @@ CollectRecordFields(const RecordDecl *re
// Field number for non-static fields.
unsigned fieldNo = 0;
- // Bookkeeping for an ms struct, which ignores certain fields.
- bool IsMsStruct = record->isMsStruct(CGM.getContext());
- const FieldDecl *LastFD = 0;
-
// Static and non-static members should appear in the same order as
// the corresponding declarations in the source program.
for (RecordDecl::decl_iterator I = record->decls_begin(),
@@ -926,13 +922,6 @@ CollectRecordFields(const RecordDecl *re
if (const VarDecl *V = dyn_cast<VarDecl>(*I))
CollectRecordStaticField(V, elements, RecordTy);
else if (FieldDecl *field = dyn_cast<FieldDecl>(*I)) {
- if (IsMsStruct) {
- // Zero-length bitfields following non-bitfield members are
- // completely ignored; we don't even count them.
- if (CGM.getContext().ZeroBitfieldFollowsNonBitfield((field), LastFD))
- continue;
- LastFD = field;
- }
CollectRecordNormalField(field, layout.getFieldOffset(fieldNo),
tunit, elements, RecordTy);
Modified: cfe/trunk/lib/CodeGen/CGExprConstant.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGExprConstant.cpp?rev=185018&r1=185017&r2=185018&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGExprConstant.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGExprConstant.cpp Wed Jun 26 15:50:34 2013
@@ -373,30 +373,16 @@ bool ConstStructBuilder::Build(InitListE
unsigned FieldNo = 0;
unsigned ElementNo = 0;
- const FieldDecl *LastFD = 0;
- bool IsMsStruct = RD->isMsStruct(CGM.getContext());
for (RecordDecl::field_iterator Field = RD->field_begin(),
FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) {
- if (IsMsStruct) {
- // Zero-length bitfields following non-bitfield members are
- // ignored:
- if (CGM.getContext().ZeroBitfieldFollowsNonBitfield(*Field, LastFD)) {
- --FieldNo;
- continue;
- }
- LastFD = *Field;
- }
-
// If this is a union, skip all the fields that aren't being initialized.
if (RD->isUnion() && ILE->getInitializedFieldInUnion() != *Field)
continue;
// Don't emit anonymous bitfields, they just affect layout.
- if (Field->isUnnamedBitfield()) {
- LastFD = *Field;
+ if (Field->isUnnamedBitfield())
continue;
- }
// Get the initializer. A struct can include fields without initializers,
// we just use explicit null values for them.
@@ -472,31 +458,17 @@ void ConstStructBuilder::Build(const APV
}
unsigned FieldNo = 0;
- const FieldDecl *LastFD = 0;
- bool IsMsStruct = RD->isMsStruct(CGM.getContext());
uint64_t OffsetBits = CGM.getContext().toBits(Offset);
for (RecordDecl::field_iterator Field = RD->field_begin(),
FieldEnd = RD->field_end(); Field != FieldEnd; ++Field, ++FieldNo) {
- if (IsMsStruct) {
- // Zero-length bitfields following non-bitfield members are
- // ignored:
- if (CGM.getContext().ZeroBitfieldFollowsNonBitfield(*Field, LastFD)) {
- --FieldNo;
- continue;
- }
- LastFD = *Field;
- }
-
// If this is a union, skip all the fields that aren't being initialized.
if (RD->isUnion() && Val.getUnionField() != *Field)
continue;
// Don't emit anonymous bitfields, they just affect layout.
- if (Field->isUnnamedBitfield()) {
- LastFD = *Field;
+ if (Field->isUnnamedBitfield())
continue;
- }
// Emit the value of the initializer.
const APValue &FieldValue =
Modified: cfe/trunk/lib/CodeGen/CGRecordLayoutBuilder.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGRecordLayoutBuilder.cpp?rev=185018&r1=185017&r2=185018&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CGRecordLayoutBuilder.cpp (original)
+++ cfe/trunk/lib/CodeGen/CGRecordLayoutBuilder.cpp Wed Jun 26 15:50:34 2013
@@ -78,9 +78,6 @@ public:
/// Packed - Whether the resulting LLVM struct will be packed or not.
bool Packed;
-
- /// IsMsStruct - Whether ms_struct is in effect or not
- bool IsMsStruct;
private:
CodeGenTypes &Types;
@@ -195,8 +192,7 @@ public:
CGRecordLayoutBuilder(CodeGenTypes &Types)
: BaseSubobjectType(0),
IsZeroInitializable(true), IsZeroInitializableAsBase(true),
- Packed(false), IsMsStruct(false),
- Types(Types) { }
+ Packed(false), Types(Types) { }
/// Layout - Will layout a RecordDecl.
void Layout(const RecordDecl *D);
@@ -207,8 +203,6 @@ public:
void CGRecordLayoutBuilder::Layout(const RecordDecl *D) {
Alignment = Types.getContext().getASTRecordLayout(D).getAlignment();
Packed = D->hasAttr<PackedAttr>();
-
- IsMsStruct = D->isMsStruct(Types.getContext());
if (D->isUnion()) {
LayoutUnion(D);
@@ -764,20 +758,10 @@ bool CGRecordLayoutBuilder::LayoutFields
return false;
unsigned FieldNo = 0;
- const FieldDecl *LastFD = 0;
for (RecordDecl::field_iterator FI = D->field_begin(), FE = D->field_end();
FI != FE; ++FI, ++FieldNo) {
FieldDecl *FD = *FI;
- if (IsMsStruct) {
- // Zero-length bitfields following non-bitfield members are
- // ignored:
- if (Types.getContext().ZeroBitfieldFollowsNonBitfield(FD, LastFD)) {
- --FieldNo;
- continue;
- }
- LastFD = FD;
- }
// If this field is a bitfield, layout all of the consecutive
// non-zero-length bitfields and the last zero-length bitfield; these will
@@ -1028,8 +1012,6 @@ CGRecordLayout *CodeGenTypes::ComputeRec
const ASTRecordLayout &AST_RL = getContext().getASTRecordLayout(D);
RecordDecl::field_iterator it = D->field_begin();
- const FieldDecl *LastFD = 0;
- bool IsMsStruct = D->isMsStruct(getContext());
for (unsigned i = 0, e = AST_RL.getFieldCount(); i != e; ++i, ++it) {
const FieldDecl *FD = *it;
@@ -1039,25 +1021,12 @@ CGRecordLayout *CodeGenTypes::ComputeRec
unsigned FieldNo = RL->getLLVMFieldNo(FD);
assert(AST_RL.getFieldOffset(i) == SL->getElementOffsetInBits(FieldNo) &&
"Invalid field offset!");
- LastFD = FD;
continue;
}
-
- if (IsMsStruct) {
- // Zero-length bitfields following non-bitfield members are
- // ignored:
- if (getContext().ZeroBitfieldFollowsNonBitfield(FD, LastFD)) {
- --i;
- continue;
- }
- LastFD = FD;
- }
// Ignore unnamed bit-fields.
- if (!FD->getDeclName()) {
- LastFD = FD;
+ if (!FD->getDeclName())
continue;
- }
// Don't inspect zero-length bitfields.
if (FD->getBitWidthValue(getContext()) == 0)
Modified: cfe/trunk/lib/CodeGen/CodeGenTBAA.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenTBAA.cpp?rev=185018&r1=185017&r2=185018&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenTBAA.cpp (original)
+++ cfe/trunk/lib/CodeGen/CodeGenTBAA.cpp Wed Jun 26 15:50:34 2013
@@ -203,18 +203,8 @@ CodeGenTBAA::CollectFields(uint64_t Base
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
unsigned idx = 0;
- const FieldDecl *LastFD = 0;
- bool IsMsStruct = RD->isMsStruct(Context);
for (RecordDecl::field_iterator i = RD->field_begin(),
e = RD->field_end(); i != e; ++i, ++idx) {
- if (IsMsStruct) {
- // Zero-length bitfields following non-bitfield members are ignored.
- if (Context.ZeroBitfieldFollowsNonBitfield(*i, LastFD)) {
- --idx;
- continue;
- }
- LastFD = *i;
- }
uint64_t Offset = BaseOffset +
Layout.getFieldOffset(idx) / Context.getCharWidth();
QualType FieldQTy = i->getType();
@@ -278,19 +268,8 @@ CodeGenTBAA::getTBAAStructTypeInfo(QualT
const ASTRecordLayout &Layout = Context.getASTRecordLayout(RD);
SmallVector <std::pair<llvm::MDNode*, uint64_t>, 4> Fields;
unsigned idx = 0;
- const FieldDecl *LastFD = 0;
- bool IsMsStruct = RD->isMsStruct(Context);
for (RecordDecl::field_iterator i = RD->field_begin(),
e = RD->field_end(); i != e; ++i, ++idx) {
- if (IsMsStruct) {
- // Zero-length bitfields following non-bitfield members are ignored.
- if (Context.ZeroBitfieldFollowsNonBitfield(*i, LastFD)) {
- --idx;
- continue;
- }
- LastFD = *i;
- }
-
QualType FieldQTy = i->getType();
llvm::MDNode *FieldNode;
if (isTBAAPathStruct(FieldQTy))
Modified: cfe/trunk/test/CodeGen/tbaa-struct.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/tbaa-struct.cpp?rev=185018&r1=185017&r2=185018&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/tbaa-struct.cpp (original)
+++ cfe/trunk/test/CodeGen/tbaa-struct.cpp Wed Jun 26 15:50:34 2013
@@ -70,5 +70,5 @@ void copy5(struct six *a, struct six *b)
// CHECK: [[TS2]] = metadata !{i64 0, i64 1, metadata !{{.*}}, i64 4, i64 2, metadata !{{.*}}, i64 8, i64 4, metadata !{{.*}}, i64 12, i64 1, metadata !{{.*}}, i64 16, i64 4, metadata {{.*}}, i64 20, i64 4, metadata {{.*}}}
// (offset, size) = (0,8) char; (0,2) char; (4,8) char
// CHECK: [[TS3]] = metadata !{i64 0, i64 8, metadata !{{.*}}, i64 0, i64 2, metadata !{{.*}}, i64 4, i64 8, metadata !{{.*}}}
-// CHECK: [[TS4]] = metadata !{i64 0, i64 1, metadata [[CHAR]], i64 1, i64 1, metadata [[CHAR]], i64 2, i64 1, metadata [[CHAR]]}
+// CHECK: [[TS4]] = metadata !{i64 0, i64 1, metadata [[CHAR]], i64 1, i64 4, metadata [[INT]], i64 1, i64 1, metadata [[CHAR]], i64 2, i64 1, metadata [[CHAR]]}
// CHECK: [[TS5]] = metadata !{i64 0, i64 1, metadata [[CHAR]], i64 4, i64 4, metadata [[INT]], i64 4, i64 1, metadata [[CHAR]], i64 5, i64 1, metadata [[CHAR]]}
Modified: cfe/trunk/test/CodeGen/tbaa.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/tbaa.cpp?rev=185018&r1=185017&r2=185018&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/tbaa.cpp (original)
+++ cfe/trunk/test/CodeGen/tbaa.cpp Wed Jun 26 15:50:34 2013
@@ -250,6 +250,6 @@ char g14(struct six *a, struct six *b) {
// PATH: [[TAG_D_b_a_f32]] = metadata !{metadata [[TYPE_D:!.*]], metadata [[TYPE_INT]], i64 12}
// PATH: [[TYPE_D]] = metadata !{metadata !"_ZTS7StructD", metadata [[TYPE_SHORT]], i64 0, metadata [[TYPE_B]], i64 4, metadata [[TYPE_INT]], i64 28, metadata [[TYPE_CHAR]], i64 32}
// PATH: [[TAG_five_b]] = metadata !{metadata [[TYPE_five:!.*]], metadata [[TYPE_CHAR]], i64 1}
-// PATH: [[TYPE_five]] = metadata !{metadata !"_ZTS4five", metadata [[TYPE_CHAR]], i64 0, metadata [[TYPE_CHAR]], i64 1, metadata [[TYPE_CHAR]], i64 2}
+// PATH: [[TYPE_five]] = metadata !{metadata !"_ZTS4five", metadata [[TYPE_CHAR]], i64 0, metadata [[TYPE_INT]], i64 1, metadata [[TYPE_CHAR]], i64 1, metadata [[TYPE_CHAR]], i64 2}
// PATH: [[TAG_six_b]] = metadata !{metadata [[TYPE_six:!.*]], metadata [[TYPE_CHAR]], i64 4}
// PATH: [[TYPE_six]] = metadata !{metadata !"_ZTS3six", metadata [[TYPE_CHAR]], i64 0, metadata [[TYPE_INT]], i64 4, metadata [[TYPE_CHAR]], i64 4, metadata [[TYPE_CHAR]], i64 5}
Added: cfe/trunk/test/SemaCXX/ms_struct.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/ms_struct.cpp?rev=185018&view=auto
==============================================================================
--- cfe/trunk/test/SemaCXX/ms_struct.cpp (added)
+++ cfe/trunk/test/SemaCXX/ms_struct.cpp Wed Jun 26 15:50:34 2013
@@ -0,0 +1,19 @@
+// RUN: %clang_cc1 -fsyntax-only -verify -triple i686-apple-darwin9 -std=c++11 %s
+// expected-no-diagnostics
+
+#pragma ms_struct on
+
+struct A {
+ unsigned long a:4;
+ unsigned char b;
+ A();
+};
+
+struct B : public A {
+ unsigned long c:16;
+ int d;
+ B();
+};
+
+static_assert(__builtin_offsetof(B, d) == 12,
+ "We can't allocate the bitfield into the padding under ms_struct");
\ No newline at end of file
More information about the cfe-commits
mailing list