More bitfield improvements.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@47260 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/AST/ASTContext.cpp b/AST/ASTContext.cpp
index def254a..bd7215d 100644
--- a/AST/ASTContext.cpp
+++ b/AST/ASTContext.cpp
@@ -331,35 +331,65 @@
bool FieldIsPacked = StructIsPacked || FD->getAttr<PackedAttr>();
uint64_t FieldSize;
unsigned FieldAlign;
- if (FD->getType()->isIncompleteType()) {
- // This must be a flexible array member; we can't directly
- // query getTypeInfo about these, so we figure it out here.
- // Flexible array members don't have any size, but they
- // have to be aligned appropriately for their element type.
+
+ if (const Expr *BitWidthExpr = FD->getBitWidth()) {
+ llvm::APSInt I(32);
+ bool BitWidthIsICE =
+ BitWidthExpr->isIntegerConstantExpr(I, *this);
+ assert (BitWidthIsICE && "Invalid BitField size expression");
+ FieldSize = I.getZExtValue();
+
+ std::pair<uint64_t, unsigned> TypeInfo = getTypeInfo(FD->getType(), L);
+ uint64_t TypeSize = TypeInfo.first;
if (const AlignedAttr *AA = FD->getAttr<AlignedAttr>())
FieldAlign = AA->getAlignment();
else if (FieldIsPacked)
FieldAlign = 8;
else {
- const ArrayType* ATy = FD->getType()->getAsArrayType();
- FieldAlign = getTypeAlign(ATy->getElementType(), L);
+ // FIXME: This is X86 specific, use 32-bit alignment for long long.
+ if (FD->getType()->isIntegerType() && TypeInfo.second > 32)
+ FieldAlign = 32;
+ else
+ FieldAlign = TypeInfo.second;
}
- FieldSize = 0;
- } else {
- std::pair<uint64_t, unsigned> FieldInfo = getTypeInfo(FD->getType(), L);
- FieldSize = FieldInfo.first;
-
- if (const AlignedAttr *AA = FD->getAttr<AlignedAttr>())
- FieldAlign = AA->getAlignment();
- else if (FieldIsPacked)
- FieldAlign = 8;
- else
- FieldAlign = FieldInfo.second;
- }
- // Round up the current record size to the field's alignment boundary.
- RecordSize = (RecordSize+FieldAlign-1) & ~(FieldAlign-1);
+ // Check if we need to add padding to give the field the correct
+ // alignment.
+ if (RecordSize % FieldAlign + FieldSize > TypeSize)
+ RecordSize = (RecordSize+FieldAlign-1) & ~(FieldAlign-1);
+
+ } else {
+ if (FD->getType()->isIncompleteType()) {
+ // This must be a flexible array member; we can't directly
+ // query getTypeInfo about these, so we figure it out here.
+ // Flexible array members don't have any size, but they
+ // have to be aligned appropriately for their element type.
+
+ if (const AlignedAttr *AA = FD->getAttr<AlignedAttr>())
+ FieldAlign = AA->getAlignment();
+ else if (FieldIsPacked)
+ FieldAlign = 8;
+ else {
+ const ArrayType* ATy = FD->getType()->getAsArrayType();
+ FieldAlign = getTypeAlign(ATy->getElementType(), L);
+ }
+ FieldSize = 0;
+ } else {
+ std::pair<uint64_t, unsigned> FieldInfo = getTypeInfo(FD->getType(), L);
+ FieldSize = FieldInfo.first;
+
+ if (const AlignedAttr *AA = FD->getAttr<AlignedAttr>())
+ FieldAlign = AA->getAlignment();
+ else if (FieldIsPacked)
+ FieldAlign = 8;
+ else
+ FieldAlign = FieldInfo.second;
+ }
+
+ // Round up the current record size to the field's alignment boundary.
+ RecordSize = (RecordSize+FieldAlign-1) & ~(FieldAlign-1);
+ }
// Place this field at the current location.
FieldOffsets[i] = RecordSize;
@@ -382,6 +412,10 @@
uint64_t FieldSize = FieldInfo.first;
unsigned FieldAlign = FieldInfo.second;
+ // FIXME: This is X86 specific, use 32-bit alignment for long long.
+ if (FD->getType()->isIntegerType() && FieldAlign > 32)
+ FieldAlign = 32;
+
// Round up the current record size to the field's alignment boundary.
RecordSize = std::max(RecordSize, FieldSize);