Compute interface instanceStart and instanceSize using the record
layout.
- This is much simpler / more efficient.
- This also properly computes the size in the presence of bit-fields.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@70916 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CGObjCMac.cpp b/lib/CodeGen/CGObjCMac.cpp
index e735efb..1a1ef83 100644
--- a/lib/CodeGen/CGObjCMac.cpp
+++ b/lib/CodeGen/CGObjCMac.cpp
@@ -4219,35 +4219,16 @@
void CGObjCNonFragileABIMac::GetClassSizeInfo(const ObjCImplementationDecl *OID,
uint32_t &InstanceStart,
uint32_t &InstanceSize) {
- // Find first and last (non-padding) ivars in this interface.
-
- // FIXME: Use iterator.
- llvm::SmallVector<ObjCIvarDecl*, 16> OIvars;
- GetNamedIvarList(OID->getClassInterface(), OIvars);
-
- if (OIvars.empty()) {
+ const ASTRecordLayout &RL =
+ CGM.getContext().getASTObjCImplementationLayout(OID);
+
+ if (!RL.getFieldCount()) {
InstanceStart = InstanceSize = 0;
return;
}
- const ObjCIvarDecl *First = OIvars.front();
- const ObjCIvarDecl *Last = OIvars.back();
-
- InstanceStart = ComputeIvarBaseOffset(CGM, OID, First);
- const llvm::Type *FieldTy =
- CGM.getTypes().ConvertTypeForMem(Last->getType());
- unsigned Size = CGM.getTargetData().getTypePaddedSize(FieldTy);
-// FIXME. This breaks compatibility with llvm-gcc-4.2 (but makes it compatible
-// with gcc-4.2). We postpone this for now.
-#if 0
- if (Last->isBitField()) {
- Expr *BitWidth = Last->getBitWidth();
- uint64_t BitFieldSize =
- BitWidth->EvaluateAsInt(CGM.getContext()).getZExtValue();
- Size = (BitFieldSize / 8) + ((BitFieldSize % 8) != 0);
- }
-#endif
- InstanceSize = ComputeIvarBaseOffset(CGM, OID, Last) + Size;
+ InstanceStart = RL.getFieldOffset(0) / 8;
+ InstanceSize = llvm::RoundUpToAlignment(RL.getNextOffset(), 8) / 8;
}
void CGObjCNonFragileABIMac::GenerateClass(const ObjCImplementationDecl *ID) {