Address more review comments for DIExpression::iterator.

- input_iterator
- define an operator->
- make constructors private were possible

llvm-svn: 226967

2 files changed, 16 insertions, 11 deletions

diff --git a/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp b/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
index 8515dd020c8..f3d3fb45bb2 100644
--- a/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/DwarfExpression.cpp
@@ -210,16 +210,16 @@ bool DwarfExpression::AddMachineRegExpression(DIExpression Expr,
   switch (*I) {
   case dwarf::DW_OP_piece: {
     unsigned SizeOfByte = 8;
-    unsigned OffsetInBits = (*I).getArg(1) * SizeOfByte;
-    unsigned SizeInBits   = (*I).getArg(2) * SizeOfByte;
+    unsigned OffsetInBits = I->getArg(1) * SizeOfByte;
+    unsigned SizeInBits   = I->getArg(2) * SizeOfByte;
     // Piece always comes at the end of the expression.
     return AddMachineRegPiece(MachineReg, SizeInBits,
                getOffsetOrZero(OffsetInBits, PieceOffsetInBits));
   }
   case dwarf::DW_OP_plus:
     // [DW_OP_reg,Offset,DW_OP_plus,DW_OP_deref] --> [DW_OP_breg,Offset].
-    if (*std::next(I) == dwarf::DW_OP_deref) {
-      unsigned Offset = (*I).getArg(1);
+    if (I->getNext() == dwarf::DW_OP_deref) {
+      unsigned Offset = I->getArg(1);
       ValidReg = AddMachineRegIndirect(MachineReg, Offset);
       std::advance(I, 2);
       break;
@@ -248,14 +248,14 @@ void DwarfExpression::AddExpression(DIExpression::iterator I,
     switch (*I) {
     case dwarf::DW_OP_piece: {
       unsigned SizeOfByte = 8;
-      unsigned OffsetInBits = (*I).getArg(1) * SizeOfByte;
-      unsigned SizeInBits   = (*I).getArg(2) * SizeOfByte;
+      unsigned OffsetInBits = I->getArg(1) * SizeOfByte;
+      unsigned SizeInBits   = I->getArg(2) * SizeOfByte;
       AddOpPiece(SizeInBits, getOffsetOrZero(OffsetInBits, PieceOffsetInBits));
       break;
     }
     case dwarf::DW_OP_plus:
       EmitOp(dwarf::DW_OP_plus_uconst);
-      EmitUnsigned((*I).getArg(1));
+      EmitUnsigned(I->getArg(1));
       break;
     case dwarf::DW_OP_deref:
       EmitOp(dwarf::DW_OP_deref);
diff --git a/llvm/lib/IR/DebugInfo.cpp b/llvm/lib/IR/DebugInfo.cpp
index 095fcbffde3..9b5a9c3da47 100644
--- a/llvm/lib/IR/DebugInfo.cpp
+++ b/llvm/lib/IR/DebugInfo.cpp
@@ -170,6 +170,11 @@ DIExpression::iterator DIExpression::end() const {
  return DIExpression::iterator();
 }
 
+const DIExpression::Operand &DIExpression::Operand::getNext() const {
+  iterator it(I);
+  return *(++it);
+}
+
 //===----------------------------------------------------------------------===//
 // Predicates
 //===----------------------------------------------------------------------===//
@@ -606,13 +611,13 @@ bool DIExpression::Verify() const {
   if (!(isExpression() && DbgNode->getNumOperands() == 1))
     return false;
 
-  for (auto E = end(), I = begin(); I != E; ++I)
-    switch (*I) {
+  for (auto Op : *this)
+    switch (Op) {
     case DW_OP_piece:
       // Must be the last element of the expression.
-      return std::distance(I.getBase(), DIHeaderFieldIterator()) == 3;
+      return std::distance(Op.getBase(), DIHeaderFieldIterator()) == 3;
     case DW_OP_plus:
-      if (std::distance(I.getBase(), DIHeaderFieldIterator()) < 2)
+      if (std::distance(Op.getBase(), DIHeaderFieldIterator()) < 2)
         return false;
       break;
     case DW_OP_deref: