Vendor import of clang release_32 branch r168974 (effectively, 3.2 RC2):

http://llvm.org/svn/llvm-project/cfe/branches/release_32@168974

1 files changed, 58 insertions, 26 deletions

diff --git a/lib/AST/RecordLayoutBuilder.cpp b/lib/AST/RecordLayoutBuilder.cpp
index d5df63f..4dfffc4 100644
--- a/lib/AST/RecordLayoutBuilder.cpp
+++ b/lib/AST/RecordLayoutBuilder.cpp
@@ -789,8 +789,8 @@ protected:
   void setDataSize(CharUnits NewSize) { DataSize = Context.toBits(NewSize); }
   void setDataSize(uint64_t NewSize) { DataSize = NewSize; }
 
-  RecordLayoutBuilder(const RecordLayoutBuilder&);   // DO NOT IMPLEMENT
-  void operator=(const RecordLayoutBuilder&); // DO NOT IMPLEMENT
+  RecordLayoutBuilder(const RecordLayoutBuilder &) LLVM_DELETED_FUNCTION;
+  void operator=(const RecordLayoutBuilder &) LLVM_DELETED_FUNCTION;
 public:
   static const CXXMethodDecl *ComputeKeyFunction(const CXXRecordDecl *RD);
 };
@@ -1557,6 +1557,13 @@ CharUnits RecordLayoutBuilder::LayoutBase(const BaseSubobjectInfo *Base) {
     bool Allowed = EmptySubobjects->CanPlaceBaseAtOffset(Base, Offset);
     (void)Allowed;
     assert(Allowed && "Base subobject externally placed at overlapping offset");
+
+    if (InferAlignment && Offset < getDataSize().RoundUpToAlignment(BaseAlign)){
+      // The externally-supplied base offset is before the base offset we
+      // computed. Assume that the structure is packed.
+      Alignment = CharUnits::One();
+      InferAlignment = false;
+    }
   }
   
   if (!Base->Class->isEmpty()) {
@@ -1574,12 +1581,12 @@ CharUnits RecordLayoutBuilder::LayoutBase(const BaseSubobjectInfo *Base) {
 }
 
 void RecordLayoutBuilder::InitializeLayout(const Decl *D) {
-  if (const RecordDecl *RD = dyn_cast<RecordDecl>(D))
+  if (const RecordDecl *RD = dyn_cast<RecordDecl>(D)) {
     IsUnion = RD->isUnion();
+    IsMsStruct = RD->isMsStruct(Context);
+  }
 
-  Packed = D->hasAttr<PackedAttr>();
-  
-  IsMsStruct = D->hasAttr<MsStructAttr>();
+  Packed = D->hasAttr<PackedAttr>();  
 
   // Honor the default struct packing maximum alignment flag.
   if (unsigned DefaultMaxFieldAlignment = Context.getLangOpts().PackStruct) {
@@ -1616,7 +1623,6 @@ void RecordLayoutBuilder::InitializeLayout(const Decl *D) {
       if (ExternalLayout) {
         if (ExternalAlign > 0) {
           Alignment = Context.toCharUnitsFromBits(ExternalAlign);
-          UnpackedAlignment = Alignment;
         } else {
           // The external source didn't have alignment information; infer it.
           InferAlignment = true;
@@ -2085,7 +2091,7 @@ void RecordLayoutBuilder::LayoutField(const FieldDecl *D) {
       ZeroLengthBitfield = 0;
     }
 
-    if (Context.getLangOpts().MSBitfields || IsMsStruct) {
+    if (IsMsStruct) {
       // If MS bitfield layout is required, figure out what type is being
       // laid out and align the field to the width of that type.
       
@@ -2166,11 +2172,6 @@ void RecordLayoutBuilder::LayoutField(const FieldDecl *D) {
 }
 
 void RecordLayoutBuilder::FinishLayout(const NamedDecl *D) {
-  if (ExternalLayout) {
-    setSize(ExternalSize);
-    return;
-  }
-  
   // In C++, records cannot be of size 0.
   if (Context.getLangOpts().CPlusPlus && getSizeInBits() == 0) {
     if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
@@ -2184,20 +2185,37 @@ void RecordLayoutBuilder::FinishLayout(const NamedDecl *D) {
       setSize(CharUnits::One());
   }
 
+  // Finally, round the size of the record up to the alignment of the
+  // record itself.
+  uint64_t UnpaddedSize = getSizeInBits() - UnfilledBitsInLastByte;
+  uint64_t UnpackedSizeInBits =
+  llvm::RoundUpToAlignment(getSizeInBits(),
+                           Context.toBits(UnpackedAlignment));
+  CharUnits UnpackedSize = Context.toCharUnitsFromBits(UnpackedSizeInBits);
+  uint64_t RoundedSize
+    = llvm::RoundUpToAlignment(getSizeInBits(), Context.toBits(Alignment));
+
+  if (ExternalLayout) {
+    // If we're inferring alignment, and the external size is smaller than
+    // our size after we've rounded up to alignment, conservatively set the
+    // alignment to 1.
+    if (InferAlignment && ExternalSize < RoundedSize) {
+      Alignment = CharUnits::One();
+      InferAlignment = false;
+    }
+    setSize(ExternalSize);
+    return;
+  }
+
+
   // MSVC doesn't round up to the alignment of the record with virtual bases.
   if (const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(D)) {
     if (isMicrosoftCXXABI() && RD->getNumVBases())
       return;
   }
 
-  // Finally, round the size of the record up to the alignment of the
-  // record itself.
-  uint64_t UnpaddedSize = getSizeInBits() - UnfilledBitsInLastByte;
-  uint64_t UnpackedSizeInBits = 
-    llvm::RoundUpToAlignment(getSizeInBits(), 
-                             Context.toBits(UnpackedAlignment));
-  CharUnits UnpackedSize = Context.toCharUnitsFromBits(UnpackedSizeInBits);
-  setSize(llvm::RoundUpToAlignment(getSizeInBits(), Context.toBits(Alignment)));
+  // Set the size to the final size.
+  setSize(RoundedSize);
 
   unsigned CharBitNum = Context.getTargetInfo().getCharWidth();
   if (const RecordDecl *RD = dyn_cast<RecordDecl>(D)) {
@@ -2255,7 +2273,7 @@ RecordLayoutBuilder::updateExternalFieldOffset(const FieldDecl *Field,
   if (InferAlignment && ExternalFieldOffset < ComputedOffset) {
     // The externally-supplied field offset is before the field offset we
     // computed. Assume that the structure is packed.
-    Alignment = CharUnits::fromQuantity(1);
+    Alignment = CharUnits::One();
     InferAlignment = false;
   }
   
@@ -2263,6 +2281,20 @@ RecordLayoutBuilder::updateExternalFieldOffset(const FieldDecl *Field,
   return ExternalFieldOffset;
 }
 
+/// \brief Get diagnostic %select index for tag kind for
+/// field padding diagnostic message.
+/// WARNING: Indexes apply to particular diagnostics only!
+///
+/// \returns diagnostic %select index.
+static unsigned getPaddingDiagFromTagKind(TagTypeKind Tag) {
+  switch (Tag) {
+  case TTK_Struct: return 0;
+  case TTK_Interface: return 1;
+  case TTK_Class: return 2;
+  default: llvm_unreachable("Invalid tag kind for field padding diagnostic!");
+  }
+}
+
 void RecordLayoutBuilder::CheckFieldPadding(uint64_t Offset,
                                             uint64_t UnpaddedOffset,
                                             uint64_t UnpackedOffset,
@@ -2291,14 +2323,14 @@ void RecordLayoutBuilder::CheckFieldPadding(uint64_t Offset,
     }
     if (D->getIdentifier())
       Diag(D->getLocation(), diag::warn_padded_struct_field)
-          << (D->getParent()->isStruct() ? 0 : 1) // struct|class
+          << getPaddingDiagFromTagKind(D->getParent()->getTagKind())
           << Context.getTypeDeclType(D->getParent())
           << PadSize
           << (InBits ? 1 : 0) /*(byte|bit)*/ << (PadSize > 1) // plural or not
           << D->getIdentifier();
     else
       Diag(D->getLocation(), diag::warn_padded_struct_anon_field)
-          << (D->getParent()->isStruct() ? 0 : 1) // struct|class
+          << getPaddingDiagFromTagKind(D->getParent()->getTagKind())
           << Context.getTypeDeclType(D->getParent())
           << PadSize
           << (InBits ? 1 : 0) /*(byte|bit)*/ << (PadSize > 1); // plural or not
@@ -2508,8 +2540,8 @@ ASTContext::getObjCLayout(const ObjCInterfaceDecl *D,
   assert(D && D->isThisDeclarationADefinition() && "Invalid interface decl!");
 
   // Look up this layout, if already laid out, return what we have.
-  ObjCContainerDecl *Key =
-    Impl ? (ObjCContainerDecl*) Impl : (ObjCContainerDecl*) D;
+  const ObjCContainerDecl *Key =
+    Impl ? (const ObjCContainerDecl*) Impl : (const ObjCContainerDecl*) D;
   if (const ASTRecordLayout *Entry = ObjCLayouts[Key])
     return *Entry;