Return iterator from BasicBlock::eraseFromParent

[• dberlin]

Summary

Same as the last patch, but for BasicBlock
(Requires same code movement)

[chandlerc]

Looks good.

include/llvm/IR/BasicBlock.h

 
 namespace llvm {
 
 class CallInst;
 class LandingPadInst;
 class TerminatorInst;
 class LLVMContext;
 class BlockAddress;
+class Function;
+
+// Traits for intrusive list of basic blocks...
+template<> struct ilist_traits<BasicBlock>
+  : public SymbolTableListTraits<BasicBlock, Function> {
+
+  BasicBlock *createSentinel() const;
+  static void destroySentinel(BasicBlock*) {}
+
+  BasicBlock *provideInitialHead() const { return createSentinel(); }
+  BasicBlock *ensureHead(BasicBlock*) const { return createSentinel(); }
+  static void noteHead(BasicBlock*, BasicBlock*) {}
+
+  static ValueSymbolTable *getSymTab(Function *ItemParent);
+private:
+  mutable ilist_half_node<BasicBlock> Sentinel;
+};
 
 
 /// \brief LLVM Basic Block Representation
 ///
 /// This represents a single basic block in LLVM. A basic block is simply a
 /// container of instructions that execute sequentially. Basic blocks are Values
 /// because they are referenced by instructions such as branches and switch
 /// tables. The type of a BasicBlock is "Type::LabelTy" because the basic block
public:
   const_iterator getFirstInsertionPt() const {
     return const_cast<BasicBlock*>(this)->getFirstInsertionPt();
   }
 
   /// \brief Unlink 'this' from the containing function, but do not delete it.
   void removeFromParent();
 
   /// \brief Unlink 'this' from the containing function and delete it.
-  void eraseFromParent();
+  ///
+  // \returns an iterator pointing to the element after the erased one.
+  iplist<BasicBlock>::iterator eraseFromParent();
 
   /// \brief Unlink this basic block from its current function and insert it
   /// into the function that \p MovePos lives in, right before \p MovePos.
   void moveBefore(BasicBlock *MovePos);
 
   /// \brief Unlink this basic block from its current function and insert it
   /// right after \p MovePos in the function \p MovePos lives in.
   void moveAfter(BasicBlock *MovePos);
private:
   }
   /// \brief Shadow Value::setValueSubclassData with a private forwarding method
   /// so that any future subclasses cannot accidentally use it.
   void setValueSubclassData(unsigned short D) {
     Value::setValueSubclassData(D);
   }
 };
 
+// createSentinel is used to get hold of the node that marks the end of the
+// list... (same trick used here as in ilist_traits<Instruction>)
+inline BasicBlock *ilist_traits<BasicBlock>::createSentinel() const {
+    return static_cast<BasicBlock*>(&Sentinel);
+}
+
 // Create wrappers for C Binding types (see CBindingWrapping.h).
 DEFINE_SIMPLE_CONVERSION_FUNCTIONS(BasicBlock, LLVMBasicBlockRef)
 
 } // End llvm namespace
 
 #endif

include/llvm/IR/Function.h

 #include "llvm/IR/GlobalObject.h"
 #include "llvm/Support/Compiler.h"
 
 namespace llvm {
 
 class FunctionType;
 class LLVMContext;
 
-// Traits for intrusive list of basic blocks...
-template<> struct ilist_traits<BasicBlock>
-  : public SymbolTableListTraits<BasicBlock, Function> {
-
-  // createSentinel is used to get hold of the node that marks the end of the
-  // list... (same trick used here as in ilist_traits<Instruction>)
-  BasicBlock *createSentinel() const {
-    return static_cast<BasicBlock*>(&Sentinel);
-  }
-  static void destroySentinel(BasicBlock*) {}
-
-  BasicBlock *provideInitialHead() const { return createSentinel(); }
-  BasicBlock *ensureHead(BasicBlock*) const { return createSentinel(); }
-  static void noteHead(BasicBlock*, BasicBlock*) {}
-
-  static ValueSymbolTable *getSymTab(Function *ItemParent);
-private:
-  mutable ilist_half_node<BasicBlock> Sentinel;
-};
-
 template<> struct ilist_traits<Argument>
   : public SymbolTableListTraits<Argument, Function> {
 
   Argument *createSentinel() const {
     return static_cast<Argument*>(&Sentinel);
   }
   static void destroySentinel(Argument*) {}
 

lib/IR/BasicBlock.cpp

void BasicBlock::setParent(Function *parent) {
   // Set Parent=parent, updating instruction symtab entries as appropriate.
   InstList.setSymTabObject(&Parent, parent);
 }
 
 void BasicBlock::removeFromParent() {
   getParent()->getBasicBlockList().remove(this);
 }
 
-void BasicBlock::eraseFromParent() {
-  getParent()->getBasicBlockList().erase(this);
+iplist<BasicBlock>::iterator BasicBlock::eraseFromParent() {
+  return getParent()->getBasicBlockList().erase(this);
 }
 
 /// Unlink this basic block from its current function and
 /// insert it into the function that MovePos lives in, right before MovePos.
 void BasicBlock::moveBefore(BasicBlock *MovePos) {
   MovePos->getParent()->getBasicBlockList().splice(MovePos,
                        getParent()->getBasicBlockList(), this);
 }