IRgen: Eliminate now unused fields from CGBitFieldInfo.

llvm-svn: 101344

clang/lib/CodeGen/CGObjCMac.cpp

@@ -124,10 +124,9 @@ LValue CGObjCRuntime::EmitValueForIvarAtOffset(CodeGen::CodeGenFunction &CGF,
   // layout object. However, this is blocked on other cleanups to the
   // Objective-C code, so for now we just live with allocating a bunch of these
   // objects.
-  unsigned FieldNo = 0; // This value is unused.
   CGBitFieldInfo *Info =
-    new (CGF.CGM.getContext()) CGBitFieldInfo(
-      LTy, FieldNo, BitOffset, BitFieldSize, IvarTy->isSignedIntegerType());
+    new (CGF.CGM.getContext()) CGBitFieldInfo(BitFieldSize,
+                                              IvarTy->isSignedIntegerType());
 
   // We always construct a single, possibly unaligned, access for this case.
   Info->setNumComponents(1);

clang/lib/CodeGen/CGRecordLayout.h

@@ -77,9 +77,6 @@ public:
   };
 
 private:
-  /// The number of access components to use.
-  unsigned NumComponents;
-
   /// The components to use to access the bit-field. We may need up to three
   /// separate components to support up to i64 bit-field access (4 + 2 + 1 byte
   /// accesses).
@@ -87,19 +84,19 @@ private:
   // FIXME: De-hardcode this, just allocate following the struct.
   AccessInfo Components[3];
 
-public:
-  CGBitFieldInfo(const llvm::Type *FieldTy, unsigned FieldNo,
-                 unsigned Start, unsigned Size, bool IsSigned)
-    : FieldTy(FieldTy), FieldNo(FieldNo),
-      Start(Start), Size(Size), IsSigned(IsSigned) {}
-
-  const llvm::Type *FieldTy;
-  unsigned FieldNo;
-
-  unsigned Start;
+  /// The total size of the bit-field, in bits.
   unsigned Size;
+
+  /// The number of access components to use.
+  unsigned NumComponents;
+
+  /// Whether the bit-field is signed.
   bool IsSigned : 1;
 
+public:
+  CGBitFieldInfo(unsigned Size, bool IsSigned)
+    : Size(Size), IsSigned(IsSigned) {}
+
 public:
   /// \brief Check whether this bit-field access is (i.e., should be sign
   /// extended on loads).

clang/lib/CodeGen/CGRecordLayoutBuilder.cpp

@@ -153,15 +153,15 @@ static CGBitFieldInfo ComputeBitFieldInfo(CodeGenTypes &Types,
   uint64_t TypeSizeInBytes = Types.getTargetData().getTypeAllocSize(Ty);
   uint64_t TypeSizeInBits = TypeSizeInBytes * 8;
 
+  unsigned StartBit = FieldOffset % TypeSizeInBits;
   bool IsSigned = FD->getType()->isSignedIntegerType();
-  CGBitFieldInfo BFI(Ty, FieldOffset / TypeSizeInBits,
-                     FieldOffset % TypeSizeInBits, FieldSize, IsSigned);
+  CGBitFieldInfo BFI(FieldSize, IsSigned);
 
   // The current policy is to always access the bit-field using the source type
   // of the bit-field. With the C bit-field rules, this implies that we always
   // use either one or two accesses, and two accesses can only occur with a
   // packed structure when the bit-field straddles an alignment boundary.
-  unsigned LowBits = std::min(FieldSize, TypeSizeInBits - BFI.Start);
+  unsigned LowBits = std::min(FieldSize, TypeSizeInBits - StartBit);
   bool NeedsHighAccess = LowBits != FieldSize;
   BFI.setNumComponents(1 + NeedsHighAccess);
 
@@ -170,7 +170,7 @@ static CGBitFieldInfo ComputeBitFieldInfo(CodeGenTypes &Types,
   LowAccess.FieldIndex = 0;
   LowAccess.FieldByteOffset =
     TypeSizeInBytes * ((FieldOffset / 8) / TypeSizeInBytes);
-  LowAccess.FieldBitStart = BFI.Start;
+  LowAccess.FieldBitStart = StartBit;
   LowAccess.AccessWidth = TypeSizeInBits;
   // FIXME: This might be wrong!
   LowAccess.AccessAlignment = 0;
@@ -565,9 +565,6 @@ void CGRecordLayout::dump() const {
 
 void CGBitFieldInfo::print(llvm::raw_ostream &OS) const {
   OS << "<CGBitFieldInfo";
-  OS << " FieldTy:" << *FieldTy;
-  OS << " FieldNo:" << FieldNo;
-  OS << " Start:" << Start;
   OS << " Size:" << Size;
   OS << " IsSigned:" << IsSigned << "\n";