X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FBasicBlock.h;h=1cd8dc55ab5834c30fca3d032716163e49d61421;hb=f1f1a4f16128ffa2910f0b1d5c7052b3697f9fcd;hp=4f4da1ca2fb65929ceb8f1054a49e9dd4dadbec1;hpb=07cf79ef537caff6d39145f190a28a336e629b6f;p=oota-llvm.git diff --git a/include/llvm/BasicBlock.h b/include/llvm/BasicBlock.h index 4f4da1ca2fb..1cd8dc55ab5 100644 --- a/include/llvm/BasicBlock.h +++ b/include/llvm/BasicBlock.h @@ -17,12 +17,15 @@ #include "llvm/Instruction.h" #include "llvm/SymbolTableListTraits.h" #include "llvm/ADT/ilist.h" +#include "llvm/ADT/Twine.h" #include "llvm/Support/DataTypes.h" namespace llvm { +class LandingPadInst; class TerminatorInst; class LLVMContext; +class BlockAddress; template<> struct ilist_traits : public SymbolTableListTraits { @@ -47,7 +50,7 @@ template<> struct ilist_traits Instruction *ensureHead(Instruction*) const { return createSentinel(); } static void noteHead(Instruction*, Instruction*) {} private: - mutable ilist_node Sentinel; + mutable ilist_half_node Sentinel; }; /// This represents a single basic block in LLVM. A basic block is simply a @@ -56,9 +59,9 @@ private: /// tables. The type of a BasicBlock is "Type::LabelTy" because the basic block /// represents a label to which a branch can jump. /// -/// A well formed basic block is formed of a list of non-terminating -/// instructions followed by a single TerminatorInst instruction. -/// TerminatorInst's may not occur in the middle of basic blocks, and must +/// A well formed basic block is formed of a list of non-terminating +/// instructions followed by a single TerminatorInst instruction. +/// TerminatorInst's may not occur in the middle of basic blocks, and must /// terminate the blocks. The BasicBlock class allows malformed basic blocks to /// occur because it may be useful in the intermediate stage of constructing or /// modifying a program. However, the verifier will ensure that basic blocks @@ -66,7 +69,7 @@ private: /// @brief LLVM Basic Block Representation class BasicBlock : public Value, // Basic blocks are data objects also public ilist_node { - + friend class BlockAddress; public: typedef iplist InstListType; private: @@ -83,13 +86,12 @@ private: /// is automatically inserted at either the end of the function (if /// InsertBefore is null), or before the specified basic block. /// - explicit BasicBlock(const std::string &Name = "", Function *Parent = 0, - BasicBlock *InsertBefore = 0); + explicit BasicBlock(LLVMContext &C, const Twine &Name = "", + Function *Parent = 0, BasicBlock *InsertBefore = 0); public: - /// getContext - Get the context in which this basic block lives, - /// or null if it is not currently attached to a function. - LLVMContext *getContext() const; - + /// getContext - Get the context in which this basic block lives. + LLVMContext &getContext() const; + /// Instruction iterators... typedef InstListType::iterator iterator; typedef InstListType::const_iterator const_iterator; @@ -97,9 +99,9 @@ public: /// Create - Creates a new BasicBlock. If the Parent parameter is specified, /// the basic block is automatically inserted at either the end of the /// function (if InsertBefore is 0), or before the specified basic block. - static BasicBlock *Create(const std::string &Name = "", Function *Parent = 0, - BasicBlock *InsertBefore = 0) { - return new BasicBlock(Name, Parent, InsertBefore); + static BasicBlock *Create(LLVMContext &Context, const Twine &Name = "", + Function *Parent = 0,BasicBlock *InsertBefore = 0) { + return new BasicBlock(Context, Name, Parent, InsertBefore); } ~BasicBlock(); @@ -109,19 +111,19 @@ public: Function *getParent() { return Parent; } /// use_back - Specialize the methods defined in Value, as we know that an - /// BasicBlock can only be used by Instructions (specifically PHI nodes and - /// terminators). - Instruction *use_back() { return cast(*use_begin());} - const Instruction *use_back() const { return cast(*use_begin());} - + /// BasicBlock can only be used by Users (specifically terminators + /// and BlockAddress's). + User *use_back() { return cast(*use_begin());} + const User *use_back() const { return cast(*use_begin());} + /// getTerminator() - If this is a well formed basic block, then this returns /// a pointer to the terminator instruction. If it is not, then you get a /// null pointer back. /// TerminatorInst *getTerminator(); const TerminatorInst *getTerminator() const; - - /// Returns a pointer to the first instructon in this block that is not a + + /// Returns a pointer to the first instructon in this block that is not a /// PHINode instruction. When adding instruction to the beginning of the /// basic block, they should be added before the returned value, not before /// the first instruction, which might be PHI. @@ -130,7 +132,27 @@ public: const Instruction* getFirstNonPHI() const { return const_cast(this)->getFirstNonPHI(); } - + + // Same as above, but also skip debug intrinsics. + Instruction* getFirstNonPHIOrDbg(); + const Instruction* getFirstNonPHIOrDbg() const { + return const_cast(this)->getFirstNonPHIOrDbg(); + } + + // Same as above, but also skip lifetime intrinsics. + Instruction* getFirstNonPHIOrDbgOrLifetime(); + const Instruction* getFirstNonPHIOrDbgOrLifetime() const { + return const_cast(this)->getFirstNonPHIOrDbgOrLifetime(); + } + + /// getFirstInsertionPt - Returns an iterator to the first instruction in this + /// block that is suitable for inserting a non-PHI instruction. In particular, + /// it skips all PHIs and LandingPad instructions. + iterator getFirstInsertionPt(); + const_iterator getFirstInsertionPt() const { + return const_cast(this)->getFirstInsertionPt(); + } + /// removeFromParent - This method unlinks 'this' from the containing /// function, but does not delete it. /// @@ -140,15 +162,15 @@ public: /// and deletes it. /// void eraseFromParent(); - + /// moveBefore - Unlink this basic block from its current function and /// insert it into the function that MovePos lives in, right before MovePos. void moveBefore(BasicBlock *MovePos); - + /// moveAfter - Unlink this basic block from its current function and /// insert it into the function that MovePos lives in, right after MovePos. void moveAfter(BasicBlock *MovePos); - + /// getSinglePredecessor - If this basic block has a single predecessor block, /// return the block, otherwise return a null pointer. @@ -159,8 +181,8 @@ public: /// getUniquePredecessor - If this basic block has a unique predecessor block, /// return the 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 + /// Note that unique predecessor doesn't mean single edge, there can be + /// multiple edges from the unique predecessor to this block (for example /// a switch statement with multiple cases having the same destination). BasicBlock *getUniquePredecessor(); const BasicBlock *getUniquePredecessor() const { @@ -232,7 +254,41 @@ public: /// cause a degenerate basic block to be formed, having a terminator inside of /// the basic block). /// - BasicBlock *splitBasicBlock(iterator I, const std::string &BBName = ""); + /// 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 = ""); + + /// hasAddressTaken - returns true if there are any uses of this basic block + /// other than direct branches, switches, etc. to it. + bool hasAddressTaken() const { return getSubclassDataFromValue() != 0; } + + /// replaceSuccessorsPhiUsesWith - Update all phi nodes in all our successors + /// to refer to basic block New instead of to us. + void replaceSuccessorsPhiUsesWith(BasicBlock *New); + + /// isLandingPad - Return true if this basic block is a landing pad. I.e., + /// it's the destination of the 'unwind' edge of an invoke instruction. + bool isLandingPad() const; + + /// getLandingPadInst() - Return the landingpad instruction associated with + /// the landing pad. + LandingPadInst *getLandingPadInst(); + +private: + /// AdjustBlockAddressRefCount - BasicBlock stores the number of BlockAddress + /// objects using it. This is almost always 0, sometimes one, possibly but + /// almost never 2, and inconceivably 3 or more. + void AdjustBlockAddressRefCount(int Amt) { + setValueSubclassData(getSubclassDataFromValue()+Amt); + assert((int)(signed char)getSubclassDataFromValue() >= 0 && + "Refcount wrap-around"); + } + // 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); + } }; } // End llvm namespace