//===-- llvm/CodeGen/MachineBasicBlock.h ------------------------*- C++ -*-===//
-//
+//
// 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.
-//
+//
//===----------------------------------------------------------------------===//
-//
+//
// Collect the sequence of machine instructions for a basic block.
//
//===----------------------------------------------------------------------===//
#define LLVM_CODEGEN_MACHINEBASICBLOCK_H
#include "llvm/CodeGen/MachineInstr.h"
-#include "Support/ilist"
-#include <iosfwd>
+#include "llvm/ADT/GraphTraits.h"
+#include "llvm/ADT/ilist"
+#include "llvm/Support/Streams.h"
namespace llvm {
class MachineFunction;
// ilist_traits
template <>
-class ilist_traits<MachineInstr> {
+struct ilist_traits<MachineInstr> {
+protected:
// this is only set by the MachineBasicBlock owning the ilist
friend class MachineBasicBlock;
MachineBasicBlock* parent;
static void setPrev(MachineInstr* N, MachineInstr* prev) { N->prev = prev; }
static void setNext(MachineInstr* N, MachineInstr* next) { N->next = next; }
- static MachineInstr* createNode();
+ static MachineInstr* createSentinel();
+ static void destroySentinel(MachineInstr *MI) { delete MI; }
void addNodeToList(MachineInstr* N);
void removeNodeFromList(MachineInstr* N);
void transferNodesFromList(
class BasicBlock;
class MachineBasicBlock {
-public:
typedef ilist<MachineInstr> Instructions;
Instructions Insts;
MachineBasicBlock *Prev, *Next;
const BasicBlock *BB;
+ int Number;
+ MachineFunction *Parent;
+
+ /// Predecessors/Successors - Keep track of the predecessor / successor
+ /// basicblocks.
std::vector<MachineBasicBlock *> Predecessors;
std::vector<MachineBasicBlock *> Successors;
+ /// LiveIns - Keep track of the physical registers that are livein of
+ /// the basicblock.
+ std::vector<unsigned> LiveIns;
+
+ /// IsLandingPad - Indicate that this basic block is entered via an
+ /// exception handler.
+ bool IsLandingPad;
+
public:
- MachineBasicBlock(const BasicBlock *bb = 0) : Prev(0), Next(0), BB(bb) {
+ explicit MachineBasicBlock(const BasicBlock *bb = 0) : Prev(0), Next(0),
+ BB(bb), Number(-1),
+ Parent(0),
+ IsLandingPad(false) {
Insts.parent = this;
}
- ~MachineBasicBlock() {}
-
+
+ ~MachineBasicBlock();
+
/// getBasicBlock - Return the LLVM basic block that this instance
/// corresponded to originally.
///
/// getParent - Return the MachineFunction containing this basic block.
///
- const MachineFunction *getParent() const;
+ const MachineFunction *getParent() const { return Parent; }
+ MachineFunction *getParent() { return Parent; }
typedef ilist<MachineInstr>::iterator iterator;
typedef ilist<MachineInstr>::const_iterator const_iterator;
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(); }
+ 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 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(); }
+ 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 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);
+
+ // Iteration support for live in sets. These sets are kept in sorted
+ // order by their register number.
+ typedef std::vector<unsigned>::iterator livein_iterator;
+ typedef std::vector<unsigned>::const_iterator const_livein_iterator;
+ livein_iterator livein_begin() { return LiveIns.begin(); }
+ const_livein_iterator livein_begin() const { return LiveIns.begin(); }
+ livein_iterator livein_end() { return LiveIns.end(); }
+ const_livein_iterator livein_end() const { return LiveIns.end(); }
+ bool livein_empty() const { return LiveIns.empty(); }
+
+ /// 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
+ /// block. This only moves the block, it does not modify the CFG or adjust
+ /// potential fall-throughs at the end of the block.
+ void moveBefore(MachineBasicBlock *NewAfter);
+ void moveAfter(MachineBasicBlock *NewBefore);
- 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 (); }
- 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 (); }
-
// Machine-CFG mutators
-
+
/// addSuccessor - Add succ as a successor of this MachineBasicBlock.
/// The Predecessors list of succ is automatically updated.
///
- void addSuccessor (MachineBasicBlock *succ) {
- Successors.push_back (succ);
- assert (std::find (Successors.begin (), Successors.end (), succ)
- == Successors.end ()
- && "Trying to addSuccessor a MBB which is already my successor");
- succ->addPredecessor (this);
- }
+ void addSuccessor(MachineBasicBlock *succ);
- /// removeSuccessor - Remove succ from the successors list of this
+ /// removeSuccessor - Remove successor from the successors list of this
/// MachineBasicBlock. The Predecessors list of succ is automatically updated.
///
- void removeSuccessor (MachineBasicBlock *succ) {
- succ->removePredecessor (this);
- std::vector<MachineBasicBlock *>::iterator goner =
- std::find (Successors.begin(), Successors.end (), succ);
- assert (goner != Successors.end ()
- && "Trying to removeSuccessor a MBB which isn't my successor");
- Successors.erase (goner);
- }
+ void removeSuccessor(MachineBasicBlock *succ);
- /// addPredecessor - Remove pred as a predecessor of this MachineBasicBlock.
- /// Don't do this unless you know what you're doing, because it doesn't
- /// update pred's successors list. Use pred->addSuccessor instead.
+ /// removeSuccessor - Remove specified successor from the successors list of
+ /// this MachineBasicBlock. The Predecessors list of succ is automatically
+ /// updated. Return the iterator to the element after the one removed.
///
- void addPredecessor (MachineBasicBlock *pred) {
- Predecessors.push_back (pred);
- assert(std::find (Predecessors.begin (), Predecessors.end (), pred)
- == Predecessors.end ()
- && "Trying to addPredecessor a MBB which is already my predecessor");
- }
-
- /// removePredecessor - Remove pred as a predecessor of this
- /// MachineBasicBlock. Don't do this unless you know what you're
- /// doing, because it doesn't update pred's successors list. Use
- /// pred->removeSuccessor instead.
- ///
- void removePredecessor (MachineBasicBlock *pred) {
- std::vector<MachineBasicBlock *>::iterator goner =
- std::find (Predecessors.begin(), Predecessors.end (), pred);
- assert (goner != Predecessors.end ()
- && "Trying to removePredecessor a MBB which isn't my predecessor");
- Predecessors.erase (goner);
- }
+ succ_iterator removeSuccessor(succ_iterator I);
+
+ /// isSuccessor - Return true if the specified MBB is a successor of this
+ /// block.
+ bool isSuccessor(MachineBasicBlock *MBB) const;
/// getFirstTerminator - returns an iterator to the first terminator
/// instruction of this basic block. If a terminator does not exist,
/// it returns end()
iterator getFirstTerminator();
+ void pop_front() { Insts.pop_front(); }
+ void pop_back() { Insts.pop_back(); }
void push_back(MachineInstr *MI) { Insts.push_back(MI); }
template<typename IT>
void insert(iterator I, IT S, IT E) { Insts.insert(I, S, E); }
MachineInstr *remove(MachineInstr *I) { return Insts.remove(I); }
void clear() { Insts.clear(); }
+ /// 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,
+ iterator To) {
+ Insts.splice(where, Other->Insts, From, To);
+ }
+
+ /// 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);
+
// Debugging methods.
void dump() const;
void print(std::ostream &OS) const;
+ void print(std::ostream *OS) const { if (OS) print(*OS); }
+
+ /// getNumber - MachineBasicBlocks are uniquely numbered at the function
+ /// level, unless they're not in a MachineFunction yet, in which case this
+ /// will return -1.
+ ///
+ int getNumber() const { return Number; }
+ void setNumber(int N) { Number = N; }
private: // Methods used to maintain doubly linked list of blocks...
- friend class ilist_traits<MachineBasicBlock>;
+ 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.
+ /// Don't do this unless you know what you're doing, because it doesn't
+ /// update pred's successors list. Use pred->addSuccessor instead.
+ ///
+ void addPredecessor(MachineBasicBlock *pred);
+
+ /// removePredecessor - Remove pred as a predecessor of this
+ /// MachineBasicBlock. Don't do this unless you know what you're
+ /// doing, because it doesn't update pred's successors list. Use
+ /// pred->removeSuccessor instead.
+ ///
+ void removePredecessor(MachineBasicBlock *pred);
+};
+
+std::ostream& operator<<(std::ostream &OS, const MachineBasicBlock &MBB);
+
+//===--------------------------------------------------------------------===//
+// GraphTraits specializations for machine basic block graphs (machine-CFGs)
+//===--------------------------------------------------------------------===//
+
+// Provide specializations of GraphTraits to be able to treat a
+// MachineFunction as a graph of MachineBasicBlocks...
+//
+
+template <> struct GraphTraits<MachineBasicBlock *> {
+ typedef MachineBasicBlock NodeType;
+ typedef MachineBasicBlock::succ_iterator ChildIteratorType;
+
+ static NodeType *getEntryNode(MachineBasicBlock *BB) { return BB; }
+ static inline ChildIteratorType child_begin(NodeType *N) {
+ return N->succ_begin();
+ }
+ static inline ChildIteratorType child_end(NodeType *N) {
+ return N->succ_end();
+ }
+};
+
+template <> struct GraphTraits<const MachineBasicBlock *> {
+ typedef const MachineBasicBlock NodeType;
+ typedef MachineBasicBlock::const_succ_iterator ChildIteratorType;
+
+ static NodeType *getEntryNode(const MachineBasicBlock *BB) { return BB; }
+ static inline ChildIteratorType child_begin(NodeType *N) {
+ return N->succ_begin();
+ }
+ static inline ChildIteratorType child_end(NodeType *N) {
+ return N->succ_end();
+ }
+};
+
+// Provide specializations of GraphTraits to be able to treat a
+// MachineFunction as a graph of MachineBasicBlocks... and to walk it
+// in inverse order. Inverse order for a function is considered
+// to be when traversing the predecessor edges of a MBB
+// instead of the successor edges.
+//
+template <> struct GraphTraits<Inverse<MachineBasicBlock*> > {
+ typedef MachineBasicBlock NodeType;
+ typedef MachineBasicBlock::pred_iterator ChildIteratorType;
+ static NodeType *getEntryNode(Inverse<MachineBasicBlock *> G) {
+ return G.Graph;
+ }
+ static inline ChildIteratorType child_begin(NodeType *N) {
+ return N->pred_begin();
+ }
+ static inline ChildIteratorType child_end(NodeType *N) {
+ return N->pred_end();
+ }
+};
+
+template <> struct GraphTraits<Inverse<const MachineBasicBlock*> > {
+ typedef const MachineBasicBlock NodeType;
+ typedef MachineBasicBlock::const_pred_iterator ChildIteratorType;
+ static NodeType *getEntryNode(Inverse<const MachineBasicBlock*> G) {
+ return G.Graph;
+ }
+ static inline ChildIteratorType child_begin(NodeType *N) {
+ return N->pred_begin();
+ }
+ static inline ChildIteratorType child_end(NodeType *N) {
+ return N->pred_end();
+ }
};
} // End llvm namespace