//
// The LLVM Compiler Infrastructure
//
-// This file was developed by the LLVM research group and is distributed under
-// the University of Illinois Open Source License. See LICENSE.TXT for details.
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/ADT/GraphTraits.h"
-#include "llvm/ADT/ilist"
-#include "llvm/Support/Streams.h"
namespace llvm {
- class MachineFunction;
-// ilist_traits
+class Pass;
+class BasicBlock;
+class MachineFunction;
+class MCSymbol;
+class StringRef;
+class raw_ostream;
+
template <>
-struct ilist_traits<MachineInstr> {
-protected:
- // this is only set by the MachineBasicBlock owning the ilist
+struct ilist_traits<MachineInstr> : public ilist_default_traits<MachineInstr> {
+private:
+ mutable ilist_half_node<MachineInstr> Sentinel;
+
+ // this is only set by the MachineBasicBlock owning the LiveList
friend class MachineBasicBlock;
- MachineBasicBlock* parent;
+ MachineBasicBlock* Parent;
public:
- ilist_traits<MachineInstr>() : parent(0) { }
-
- static MachineInstr* getPrev(MachineInstr* N) { return N->prev; }
- static MachineInstr* getNext(MachineInstr* N) { return N->next; }
-
- static const MachineInstr*
- getPrev(const MachineInstr* N) { return N->prev; }
-
- static const MachineInstr*
- getNext(const MachineInstr* N) { return N->next; }
+ MachineInstr *createSentinel() const {
+ return static_cast<MachineInstr*>(&Sentinel);
+ }
+ void destroySentinel(MachineInstr *) const {}
- static void setPrev(MachineInstr* N, MachineInstr* prev) { N->prev = prev; }
- static void setNext(MachineInstr* N, MachineInstr* next) { N->next = next; }
+ MachineInstr *provideInitialHead() const { return createSentinel(); }
+ MachineInstr *ensureHead(MachineInstr*) const { return createSentinel(); }
+ static void noteHead(MachineInstr*, MachineInstr*) {}
- static MachineInstr* createSentinel();
- static void destroySentinel(MachineInstr *MI) { delete MI; }
void addNodeToList(MachineInstr* N);
void removeNodeFromList(MachineInstr* N);
- void transferNodesFromList(
- iplist<MachineInstr, ilist_traits<MachineInstr> >& toList,
- ilist_iterator<MachineInstr> first,
- ilist_iterator<MachineInstr> last);
+ void transferNodesFromList(ilist_traits &SrcTraits,
+ ilist_iterator<MachineInstr> first,
+ ilist_iterator<MachineInstr> last);
+ void deleteNode(MachineInstr *N);
+private:
+ void createNode(const MachineInstr &);
};
-class BasicBlock;
-
-class MachineBasicBlock {
-public:
+class MachineBasicBlock : public ilist_node<MachineBasicBlock> {
typedef ilist<MachineInstr> Instructions;
Instructions Insts;
- MachineBasicBlock *Prev, *Next;
const BasicBlock *BB;
+ int Number;
+ MachineFunction *xParent;
+
+ /// Predecessors/Successors - Keep track of the predecessor / successor
+ /// basicblocks.
std::vector<MachineBasicBlock *> Predecessors;
std::vector<MachineBasicBlock *> Successors;
- int Number;
- MachineFunction *Parent;
-public:
- MachineBasicBlock(const BasicBlock *bb = 0) : Prev(0), Next(0), BB(bb),
- Number(-1), Parent(0) {
- Insts.parent = this;
- }
+ /// LiveIns - Keep track of the physical registers that are livein of
+ /// the basicblock.
+ std::vector<unsigned> LiveIns;
+
+ /// Alignment - Alignment of the basic block. Zero if the basic block does
+ /// not need to be aligned.
+ unsigned Alignment;
+
+ /// IsLandingPad - Indicate that this basic block is entered via an
+ /// exception handler.
+ bool IsLandingPad;
+
+ /// AddressTaken - Indicate that this basic block is potentially the
+ /// target of an indirect branch.
+ bool AddressTaken;
+
+ // Intrusive list support
+ MachineBasicBlock() {}
+
+ explicit MachineBasicBlock(MachineFunction &mf, const BasicBlock *bb);
~MachineBasicBlock();
+ // MachineBasicBlocks are allocated and owned by MachineFunction.
+ friend class MachineFunction;
+
+public:
/// getBasicBlock - Return the LLVM basic block that this instance
- /// corresponded to originally.
+ /// corresponded to originally. Note that this may be NULL if this instance
+ /// does not correspond directly to an LLVM basic block.
///
const BasicBlock *getBasicBlock() const { return BB; }
+ /// getName - Return the name of the corresponding LLVM basic block, or
+ /// "(null)".
+ StringRef getName() const;
+
+ /// hasAddressTaken - Test whether this block is potentially the target
+ /// of an indirect branch.
+ bool hasAddressTaken() const { return AddressTaken; }
+
+ /// setHasAddressTaken - Set this block to reflect that it potentially
+ /// is the target of an indirect branch.
+ void setHasAddressTaken() { AddressTaken = true; }
+
/// getParent - Return the MachineFunction containing this basic block.
///
- const MachineFunction *getParent() const { return Parent; }
- MachineFunction *getParent() { return Parent; }
+ const MachineFunction *getParent() const { return xParent; }
+ MachineFunction *getParent() { return xParent; }
- typedef ilist<MachineInstr>::iterator iterator;
- typedef ilist<MachineInstr>::const_iterator const_iterator;
+ typedef Instructions::iterator iterator;
+ typedef Instructions::const_iterator const_iterator;
typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
typedef std::reverse_iterator<iterator> reverse_iterator;
- unsigned size() const { return Insts.size(); }
+ unsigned size() const { return (unsigned)Insts.size(); }
bool empty() const { return Insts.empty(); }
MachineInstr& front() { return Insts.front(); }
MachineInstr& back() { return Insts.back(); }
+ const MachineInstr& front() const { return Insts.front(); }
+ const MachineInstr& back() const { return Insts.back(); }
iterator begin() { return Insts.begin(); }
const_iterator begin() const { return Insts.begin(); }
typedef std::vector<MachineBasicBlock *>::const_iterator const_pred_iterator;
typedef std::vector<MachineBasicBlock *>::iterator succ_iterator;
typedef std::vector<MachineBasicBlock *>::const_iterator const_succ_iterator;
+ typedef std::vector<MachineBasicBlock *>::reverse_iterator
+ pred_reverse_iterator;
+ typedef std::vector<MachineBasicBlock *>::const_reverse_iterator
+ const_pred_reverse_iterator;
+ typedef std::vector<MachineBasicBlock *>::reverse_iterator
+ succ_reverse_iterator;
+ typedef std::vector<MachineBasicBlock *>::const_reverse_iterator
+ const_succ_reverse_iterator;
pred_iterator pred_begin() { return Predecessors.begin(); }
const_pred_iterator pred_begin() const { return Predecessors.begin(); }
pred_iterator pred_end() { return Predecessors.end(); }
const_pred_iterator pred_end() const { return Predecessors.end(); }
- unsigned pred_size() const { return Predecessors.size(); }
+ pred_reverse_iterator pred_rbegin()
+ { return Predecessors.rbegin();}
+ const_pred_reverse_iterator pred_rbegin() const
+ { return Predecessors.rbegin();}
+ pred_reverse_iterator pred_rend()
+ { return Predecessors.rend(); }
+ const_pred_reverse_iterator pred_rend() const
+ { return Predecessors.rend(); }
+ unsigned pred_size() const {
+ return (unsigned)Predecessors.size();
+ }
bool pred_empty() const { return Predecessors.empty(); }
succ_iterator succ_begin() { return Successors.begin(); }
const_succ_iterator succ_begin() const { return Successors.begin(); }
succ_iterator succ_end() { return Successors.end(); }
const_succ_iterator succ_end() const { return Successors.end(); }
- unsigned succ_size() const { return Successors.size(); }
+ succ_reverse_iterator succ_rbegin()
+ { return Successors.rbegin(); }
+ const_succ_reverse_iterator succ_rbegin() const
+ { return Successors.rbegin(); }
+ succ_reverse_iterator succ_rend()
+ { return Successors.rend(); }
+ const_succ_reverse_iterator succ_rend() const
+ { return Successors.rend(); }
+ unsigned succ_size() const {
+ return (unsigned)Successors.size();
+ }
bool succ_empty() const { return Successors.empty(); }
+ // LiveIn management methods.
+
+ /// addLiveIn - Add the specified register as a live in. Note that it
+ /// is an error to add the same register to the same set more than once.
+ void addLiveIn(unsigned Reg) { LiveIns.push_back(Reg); }
+
+ /// removeLiveIn - Remove the specified register from the live in set.
+ ///
+ void removeLiveIn(unsigned Reg);
+
+ /// isLiveIn - Return true if the specified register is in the live in set.
+ ///
+ bool isLiveIn(unsigned Reg) const;
+
+ // Iteration support for live in sets. These sets are kept in sorted
+ // order by their register number.
+ typedef std::vector<unsigned>::const_iterator livein_iterator;
+ livein_iterator livein_begin() const { return LiveIns.begin(); }
+ livein_iterator livein_end() const { return LiveIns.end(); }
+ bool livein_empty() const { return LiveIns.empty(); }
+
+ /// getAlignment - Return alignment of the basic block.
+ ///
+ unsigned getAlignment() const { return Alignment; }
+
+ /// setAlignment - Set alignment of the basic block.
+ ///
+ void setAlignment(unsigned Align) { Alignment = Align; }
+
+ /// isLandingPad - Returns true if the block is a landing pad. That is
+ /// this basic block is entered via an exception handler.
+ bool isLandingPad() const { return IsLandingPad; }
+
+ /// setIsLandingPad - Indicates the block is a landing pad. That is
+ /// this basic block is entered via an exception handler.
+ void setIsLandingPad() { IsLandingPad = true; }
+
// Code Layout methods.
/// moveBefore/moveAfter - move 'this' block before or after the specified
/// potential fall-throughs at the end of the block.
void moveBefore(MachineBasicBlock *NewAfter);
void moveAfter(MachineBasicBlock *NewBefore);
-
+
+ /// updateTerminator - Update the terminator instructions in block to account
+ /// for changes to the layout. If the block previously used a fallthrough,
+ /// it may now need a branch, and if it previously used branching it may now
+ /// be able to use a fallthrough.
+ void updateTerminator();
+
// Machine-CFG mutators
/// addSuccessor - Add succ as a successor of this MachineBasicBlock.
/// removeSuccessor - Remove specified successor from the successors list of
/// this MachineBasicBlock. The Predecessors list of succ is automatically
- /// updated.
+ /// updated. Return the iterator to the element after the one removed.
///
- void removeSuccessor(succ_iterator I);
+ succ_iterator removeSuccessor(succ_iterator I);
+
+ /// transferSuccessors - Transfers all the successors from MBB to this
+ /// machine basic block (i.e., copies all the successors fromMBB and
+ /// remove all the successors from fromMBB).
+ void transferSuccessors(MachineBasicBlock *fromMBB);
/// isSuccessor - Return true if the specified MBB is a successor of this
/// block.
- bool isSuccessor(MachineBasicBlock *MBB) const {
- for (const_succ_iterator I = succ_begin(), E = succ_end(); I != E; ++I)
- if (*I == MBB)
- return true;
- return false;
- }
+ bool isSuccessor(const MachineBasicBlock *MBB) const;
+
+ /// isLayoutSuccessor - Return true if the specified MBB will be emitted
+ /// immediately after this block, such that if this block exits by
+ /// falling through, control will transfer to the specified MBB. Note
+ /// that MBB need not be a successor at all, for example if this block
+ /// ends with an unconditional branch to some other block.
+ bool isLayoutSuccessor(const MachineBasicBlock *MBB) const;
+
+ /// canFallThrough - Return true if the block can implicitly transfer
+ /// control to the block after it by falling off the end of it. This should
+ /// return false if it can reach the block after it, but it uses an explicit
+ /// branch to do so (e.g., a table jump). True is a conservative answer.
+ bool canFallThrough();
/// getFirstTerminator - returns an iterator to the first terminator
/// instruction of this basic block. If a terminator does not exist,
/// it returns end()
iterator getFirstTerminator();
+ /// SplitCriticalEdge - Split the critical edge from this block to the
+ /// given successor block, and return the newly created block, or null
+ /// if splitting is not possible.
+ ///
+ /// This function updates LiveVariables, MachineDominatorTree, and
+ /// MachineLoopInfo, as applicable.
+ MachineBasicBlock *SplitCriticalEdge(MachineBasicBlock *Succ, Pass *P);
+
void pop_front() { Insts.pop_front(); }
void pop_back() { Insts.pop_back(); }
void push_back(MachineInstr *MI) { Insts.push_back(MI); }
MachineInstr *remove(MachineInstr *I) { return Insts.remove(I); }
void clear() { Insts.clear(); }
+ /// splice - Take an instruction from MBB 'Other' at the position From,
+ /// and insert it into this MBB right before 'where'.
+ void splice(iterator where, MachineBasicBlock *Other, iterator From) {
+ Insts.splice(where, Other->Insts, From);
+ }
+
/// splice - Take a block of instructions from MBB 'Other' in the range [From,
/// To), and insert them into this MBB right before 'where'.
void splice(iterator where, MachineBasicBlock *Other, iterator From,
Insts.splice(where, Other->Insts, From, To);
}
+ /// removeFromParent - This method unlinks 'this' from the containing
+ /// function, and returns it, but does not delete it.
+ MachineBasicBlock *removeFromParent();
+
+ /// eraseFromParent - This method unlinks 'this' from the containing
+ /// function and deletes it.
+ void eraseFromParent();
+
+ /// ReplaceUsesOfBlockWith - Given a machine basic block that branched to
+ /// 'Old', change the code and CFG so that it branches to 'New' instead.
+ void ReplaceUsesOfBlockWith(MachineBasicBlock *Old, MachineBasicBlock *New);
+
+ /// CorrectExtraCFGEdges - Various pieces of code can cause excess edges in
+ /// the CFG to be inserted. If we have proven that MBB can only branch to
+ /// DestA and DestB, remove any other MBB successors from the CFG. DestA and
+ /// DestB can be null. Besides DestA and DestB, retain other edges leading
+ /// to LandingPads (currently there can be only one; we don't check or require
+ /// that here). Note it is possible that DestA and/or DestB are LandingPads.
+ bool CorrectExtraCFGEdges(MachineBasicBlock *DestA,
+ MachineBasicBlock *DestB,
+ bool isCond);
+
+ /// findDebugLoc - find the next valid DebugLoc starting at MBBI, skipping
+ /// any DBG_VALUE instructions. Return UnknownLoc if there is none.
+ DebugLoc findDebugLoc(MachineBasicBlock::iterator &MBBI);
+
// Debugging methods.
void dump() const;
- void print(OStream &OS) const {
- if (OS.stream()) print(*OS.stream());
- }
- void print(std::ostream &OS) const;
+ void print(raw_ostream &OS) const;
/// getNumber - MachineBasicBlocks are uniquely numbered at the function
/// level, unless they're not in a MachineFunction yet, in which case this
int getNumber() const { return Number; }
void setNumber(int N) { Number = N; }
+ /// getSymbol - Return the MCSymbol for this basic block.
+ ///
+ MCSymbol *getSymbol() const;
+
private: // Methods used to maintain doubly linked list of blocks...
friend struct ilist_traits<MachineBasicBlock>;
- MachineBasicBlock *getPrev() const { return Prev; }
- MachineBasicBlock *getNext() const { return Next; }
- void setPrev(MachineBasicBlock *P) { Prev = P; }
- void setNext(MachineBasicBlock *N) { Next = N; }
-
// Machine-CFG mutators
/// addPredecessor - Remove pred as a predecessor of this MachineBasicBlock.
void removePredecessor(MachineBasicBlock *pred);
};
-std::ostream& operator<<(std::ostream &OS, const MachineBasicBlock &MBB);
-inline OStream& operator<<(OStream &OS, const MachineBasicBlock &MBB) {
- if (OS.stream()) MBB.print(*OS.stream());
- return OS;
-}
+raw_ostream& operator<<(raw_ostream &OS, const MachineBasicBlock &MBB);
+
+void WriteAsOperand(raw_ostream &, const MachineBasicBlock*, bool t);
//===--------------------------------------------------------------------===//
// GraphTraits specializations for machine basic block graphs (machine-CFGs)
projects / oota-llvm.git / blobdiff