namespace llvm {
+class CallInst;
class LandingPadInst;
class TerminatorInst;
class LLVMContext;
class BlockAddress;
+class Function;
-template<> struct ilist_traits<Instruction>
- : public SymbolTableListTraits<Instruction, BasicBlock> {
-
- /// \brief Return a node that marks the end of a list.
- ///
- /// The sentinel is relative to this instance, so we use a non-static
- /// method.
- Instruction *createSentinel() const {
- // Since i(p)lists always publicly derive from their corresponding traits,
- // placing a data member in this class will augment the i(p)list. But since
- // the NodeTy is expected to be publicly derive from ilist_node<NodeTy>,
- // there is a legal viable downcast from it to NodeTy. We use this trick to
- // superimpose an i(p)list with a "ghostly" NodeTy, which becomes the
- // sentinel. Dereferencing the sentinel is forbidden (save the
- // ilist_node<NodeTy>), so no one will ever notice the superposition.
- return static_cast<Instruction*>(&Sentinel);
- }
- static void destroySentinel(Instruction*) {}
-
- Instruction *provideInitialHead() const { return createSentinel(); }
- Instruction *ensureHead(Instruction*) const { return createSentinel(); }
- static void noteHead(Instruction*, Instruction*) {}
-private:
- mutable ilist_half_node<Instruction> Sentinel;
-};
+template <>
+struct SymbolTableListSentinelTraits<BasicBlock>
+ : public ilist_half_embedded_sentinel_traits<BasicBlock> {};
/// \brief LLVM Basic Block Representation
///
/// modifying a program. However, the verifier will ensure that basic blocks
/// are "well formed".
class BasicBlock : public Value, // Basic blocks are data objects also
- public ilist_node<BasicBlock> {
+ public ilist_node_with_parent<BasicBlock, Function> {
friend class BlockAddress;
public:
- typedef iplist<Instruction> InstListType;
+ typedef SymbolTableList<Instruction> InstListType;
+
private:
InstListType InstList;
Function *Parent;
void setParent(Function *parent);
- friend class SymbolTableListTraits<BasicBlock, Function>;
+ friend class SymbolTableListTraits<BasicBlock>;
- BasicBlock(const BasicBlock &) LLVM_DELETED_FUNCTION;
- void operator=(const BasicBlock &) LLVM_DELETED_FUNCTION;
+ BasicBlock(const BasicBlock &) = delete;
+ void operator=(const BasicBlock &) = delete;
/// \brief Constructor.
///
/// inserted at either the end of the function (if InsertBefore is null), or
/// before the specified basic block.
explicit BasicBlock(LLVMContext &C, const Twine &Name = "",
- Function *Parent = 0, BasicBlock *InsertBefore = 0);
+ Function *Parent = nullptr,
+ BasicBlock *InsertBefore = nullptr);
public:
/// \brief Get the context in which this basic block lives.
LLVMContext &getContext() const;
/// inserted at either the end of the function (if InsertBefore is 0), or
/// before the specified basic block.
static BasicBlock *Create(LLVMContext &Context, const Twine &Name = "",
- Function *Parent = 0,BasicBlock *InsertBefore = 0) {
+ Function *Parent = nullptr,
+ BasicBlock *InsertBefore = nullptr) {
return new BasicBlock(Context, Name, Parent, InsertBefore);
}
- ~BasicBlock();
+ ~BasicBlock() override;
/// \brief Return the enclosing method, or null if none.
const Function *getParent() const { return Parent; }
Function *getParent() { return Parent; }
+ /// \brief Return the module owning the function this basic block belongs to,
+ /// or nullptr it the function does not have a module.
+ ///
+ /// Note: this is undefined behavior if the block does not have a parent.
+ const Module *getModule() const;
+ Module *getModule();
+
/// \brief Returns the terminator instruction if the block is well formed or
/// null if the block is not well formed.
TerminatorInst *getTerminator();
const TerminatorInst *getTerminator() const;
+ /// \brief Returns the call instruction marked 'musttail' prior to the
+ /// terminating return instruction of this basic block, if such a call is
+ /// present. Otherwise, returns null.
+ CallInst *getTerminatingMustTailCall();
+ const CallInst *getTerminatingMustTailCall() const {
+ return const_cast<BasicBlock *>(this)->getTerminatingMustTailCall();
+ }
+
/// \brief Returns a pointer to the first instruction in this block that is
/// not a PHINode instruction.
///
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.
+ SymbolTableList<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.
/// right after \p MovePos in the function \p MovePos lives in.
void moveAfter(BasicBlock *MovePos);
+ /// \brief Insert unlinked basic block into a function.
+ ///
+ /// Inserts an unlinked basic block into \c Parent. If \c InsertBefore is
+ /// provided, inserts before that basic block, otherwise inserts at the end.
+ ///
+ /// \pre \a getParent() is \c nullptr.
+ void insertInto(Function *Parent, BasicBlock *InsertBefore = nullptr);
- /// \brief Return this block if it has a single predecessor block. Otherwise
- /// return a null pointer.
+ /// \brief Return the predecessor of this block if it has a single predecessor
+ /// block. Otherwise return a null pointer.
BasicBlock *getSinglePredecessor();
const BasicBlock *getSinglePredecessor() const {
return const_cast<BasicBlock*>(this)->getSinglePredecessor();
}
- /// \brief Return this block if it has a unique predecessor block. Otherwise return a null pointer.
+ /// \brief Return the predecessor of this block if it has a unique predecessor
+ /// block. Otherwise return a null pointer.
///
/// Note that unique predecessor doesn't mean single edge, there can be
/// multiple edges from the unique predecessor to this block (for example a
return const_cast<BasicBlock*>(this)->getUniquePredecessor();
}
+ /// \brief Return the successor of this block if it has a single successor.
+ /// Otherwise return a null pointer.
+ ///
+ /// This method is analogous to getSinglePredecessor above.
+ BasicBlock *getSingleSuccessor();
+ const BasicBlock *getSingleSuccessor() const {
+ return const_cast<BasicBlock*>(this)->getSingleSuccessor();
+ }
+
+ /// \brief Return the successor of this block if it has a unique successor.
+ /// Otherwise return a null pointer.
+ ///
+ /// This method is analogous to getUniquePredecessor above.
+ BasicBlock *getUniqueSuccessor();
+ const BasicBlock *getUniqueSuccessor() const {
+ return const_cast<BasicBlock*>(this)->getUniqueSuccessor();
+ }
+
//===--------------------------------------------------------------------===//
/// Instruction iterator methods
///
InstListType &getInstList() { return InstList; }
/// \brief Returns a pointer to a member of the instruction list.
- static iplist<Instruction> BasicBlock::*getSublistAccess(Instruction*) {
+ static InstListType BasicBlock::*getSublistAccess(Instruction*) {
return &BasicBlock::InstList;
}
/// should be called while the predecessor still refers to this block.
void removePredecessor(BasicBlock *Pred, bool DontDeleteUselessPHIs = false);
+ bool canSplitPredecessors() const;
+
/// \brief Split the basic block into two basic blocks at the specified
/// instruction.
///
/// Also note that this doesn't preserve any passes. To split blocks while
/// keeping loop information consistent, use the SplitBlock utility function.
BasicBlock *splitBasicBlock(iterator I, const Twine &BBName = "");
+ BasicBlock *splitBasicBlock(Instruction *I, const Twine &BBName = "") {
+ return splitBasicBlock(I->getIterator(), BBName);
+ }
/// \brief Returns true if there are any uses of this basic block other than
/// direct branches, switches, etc. to it.
/// basic block \p New instead of to it.
void replaceSuccessorsPhiUsesWith(BasicBlock *New);
+ /// \brief Return true if this basic block is an exception handling block.
+ bool isEHPad() const { return getFirstNonPHI()->isEHPad(); }
+
/// \brief Return true if this basic block is a landing pad.
///
/// Being a ``landing pad'' means that the basic block is the destination of