#ifndef LLVM_CODEGEN_MACHINEBASICBLOCK_H
#define LLVM_CODEGEN_MACHINEBASICBLOCK_H
-#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/ADT/GraphTraits.h"
+#include "llvm/CodeGen/MachineInstr.h"
+#include "llvm/Support/DataTypes.h"
+#include <functional>
namespace llvm {
class SlotIndexes;
class StringRef;
class raw_ostream;
+class MachineBranchProbabilityInfo;
template <>
struct ilist_traits<MachineInstr> : public ilist_default_traits<MachineInstr> {
const BasicBlock *BB;
int Number;
MachineFunction *xParent;
-
+
/// Predecessors/Successors - Keep track of the predecessor / successor
/// basicblocks.
std::vector<MachineBasicBlock *> Predecessors;
std::vector<MachineBasicBlock *> Successors;
+
+ /// Weights - Keep track of the weights to the successors. This vector
+ /// has the same order as Successors, or it is empty if we don't use it
+ /// (disable optimization).
+ std::vector<uint32_t> Weights;
+ typedef std::vector<uint32_t>::iterator weight_iterator;
+ typedef std::vector<uint32_t>::const_iterator const_weight_iterator;
+
/// 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.
+ /// The alignment is specified as log2(bytes).
unsigned Alignment;
-
+
/// IsLandingPad - Indicate that this basic block is entered via an
/// exception handler.
bool IsLandingPad;
/// "(null)".
StringRef getName() const;
+ /// getFullName - Return a formatted string to identify this block and its
+ /// parent function.
+ std::string getFullName() const;
+
/// hasAddressTaken - Test whether this block is potentially the target
/// of an indirect branch.
bool hasAddressTaken() const { return AddressTaken; }
const MachineFunction *getParent() const { return xParent; }
MachineFunction *getParent() { return xParent; }
- 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;
+
+ /// bundle_iterator - MachineBasicBlock iterator that automatically skips over
+ /// MIs that are inside bundles (i.e. walk top level MIs only).
+ template<typename Ty, typename IterTy>
+ class bundle_iterator
+ : public std::iterator<std::bidirectional_iterator_tag, Ty, ptrdiff_t> {
+ IterTy MII;
+
+ public:
+ bundle_iterator(IterTy mii) : MII(mii) {}
+
+ bundle_iterator(Ty &mi) : MII(mi) {
+ assert(!mi.isBundledWithPred() &&
+ "It's not legal to initialize bundle_iterator with a bundled MI");
+ }
+ bundle_iterator(Ty *mi) : MII(mi) {
+ assert((!mi || !mi->isBundledWithPred()) &&
+ "It's not legal to initialize bundle_iterator with a bundled MI");
+ }
+ // Template allows conversion from const to nonconst.
+ template<class OtherTy, class OtherIterTy>
+ bundle_iterator(const bundle_iterator<OtherTy, OtherIterTy> &I)
+ : MII(I.getInstrIterator()) {}
+ bundle_iterator() : MII(0) {}
+
+ Ty &operator*() const { return *MII; }
+ Ty *operator->() const { return &operator*(); }
+
+ operator Ty*() const { return MII; }
+
+ bool operator==(const bundle_iterator &x) const {
+ return MII == x.MII;
+ }
+ bool operator!=(const bundle_iterator &x) const {
+ return !operator==(x);
+ }
+
+ // Increment and decrement operators...
+ bundle_iterator &operator--() { // predecrement - Back up
+ do --MII;
+ while (MII->isBundledWithPred());
+ return *this;
+ }
+ bundle_iterator &operator++() { // preincrement - Advance
+ while (MII->isBundledWithSucc())
+ ++MII;
+ ++MII;
+ return *this;
+ }
+ bundle_iterator operator--(int) { // postdecrement operators...
+ bundle_iterator tmp = *this;
+ --*this;
+ return tmp;
+ }
+ bundle_iterator operator++(int) { // postincrement operators...
+ bundle_iterator tmp = *this;
+ ++*this;
+ return tmp;
+ }
+
+ IterTy getInstrIterator() const {
+ return MII;
+ }
+ };
+
+ typedef Instructions::iterator instr_iterator;
+ typedef Instructions::const_iterator const_instr_iterator;
+ typedef std::reverse_iterator<instr_iterator> reverse_instr_iterator;
+ typedef
+ std::reverse_iterator<const_instr_iterator> const_reverse_instr_iterator;
+
+ typedef
+ bundle_iterator<MachineInstr,instr_iterator> iterator;
+ typedef
+ bundle_iterator<const MachineInstr,const_instr_iterator> const_iterator;
+ typedef std::reverse_iterator<const_iterator> const_reverse_iterator;
+ typedef std::reverse_iterator<iterator> reverse_iterator;
+
unsigned size() const { return (unsigned)Insts.size(); }
bool empty() const { return Insts.empty(); }
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(); }
- iterator end() { return Insts.end(); }
- const_iterator end() const { return Insts.end(); }
- reverse_iterator rbegin() { return Insts.rbegin(); }
- const_reverse_iterator rbegin() const { return Insts.rbegin(); }
- reverse_iterator rend () { return Insts.rend(); }
- const_reverse_iterator rend () const { return Insts.rend(); }
+ instr_iterator instr_begin() { return Insts.begin(); }
+ const_instr_iterator instr_begin() const { return Insts.begin(); }
+ instr_iterator instr_end() { return Insts.end(); }
+ const_instr_iterator instr_end() const { return Insts.end(); }
+ reverse_instr_iterator instr_rbegin() { return Insts.rbegin(); }
+ const_reverse_instr_iterator instr_rbegin() const { return Insts.rbegin(); }
+ reverse_instr_iterator instr_rend () { return Insts.rend(); }
+ const_reverse_instr_iterator instr_rend () const { return Insts.rend(); }
+
+ iterator begin() { return instr_begin(); }
+ const_iterator begin() const { return instr_begin(); }
+ iterator end () { return instr_end(); }
+ const_iterator end () const { return instr_end(); }
+ reverse_iterator rbegin() { return instr_rbegin(); }
+ const_reverse_iterator rbegin() const { return instr_rbegin(); }
+ reverse_iterator rend () { return instr_rend(); }
+ const_reverse_iterator rend () const { return instr_rend(); }
+
// Machine-CFG iterators
typedef std::vector<MachineBasicBlock *>::iterator pred_iterator;
bool livein_empty() const { return LiveIns.empty(); }
/// getAlignment - Return alignment of the basic block.
+ /// The alignment is specified as log2(bytes).
///
unsigned getAlignment() const { return Alignment; }
/// setAlignment - Set alignment of the basic block.
+ /// The alignment is specified as log2(bytes).
///
void setAlignment(unsigned Align) { Alignment = Align; }
/// setIsLandingPad - Indicates the block is a landing pad. That is
/// this basic block is entered via an exception handler.
- void setIsLandingPad() { IsLandingPad = true; }
+ void setIsLandingPad(bool V = true) { IsLandingPad = V; }
+
+ /// getLandingPadSuccessor - If this block has a successor that is a landing
+ /// pad, return it. Otherwise return NULL.
+ const MachineBasicBlock *getLandingPadSuccessor() const;
// 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 updateTerminator();
// Machine-CFG mutators
-
+
/// addSuccessor - Add succ as a successor of this MachineBasicBlock.
- /// The Predecessors list of succ is automatically updated.
+ /// The Predecessors list of succ is automatically updated. WEIGHT
+ /// parameter is stored in Weights list and it may be used by
+ /// MachineBranchProbabilityInfo analysis to calculate branch probability.
///
- void addSuccessor(MachineBasicBlock *succ);
+ /// Note that duplicate Machine CFG edges are not allowed.
+ ///
+ void addSuccessor(MachineBasicBlock *succ, uint32_t weight = 0);
/// removeSuccessor - Remove 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.
///
succ_iterator removeSuccessor(succ_iterator I);
-
+
+ /// replaceSuccessor - Replace successor OLD with NEW and update weight info.
+ ///
+ void replaceSuccessor(MachineBasicBlock *Old, MachineBasicBlock *New);
+
+
/// 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).
/// in transferSuccessors, and update PHI operands in the successor blocks
/// which refer to fromMBB to refer to this.
void transferSuccessorsAndUpdatePHIs(MachineBasicBlock *fromMBB);
-
+
+ /// isPredecessor - Return true if the specified MBB is a predecessor of this
+ /// block.
+ bool isPredecessor(const MachineBasicBlock *MBB) const;
+
/// isSuccessor - Return true if the specified MBB is a successor of this
/// block.
bool isSuccessor(const MachineBasicBlock *MBB) const;
/// branch to do so (e.g., a table jump). True is a conservative answer.
bool canFallThrough();
- /// 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.
/// instruction of this basic block. If a terminator does not exist,
/// it returns end()
iterator getFirstTerminator();
+ const_iterator getFirstTerminator() const;
+
+ /// getFirstInstrTerminator - Same getFirstTerminator but it ignores bundles
+ /// and return an instr_iterator instead.
+ instr_iterator getFirstInstrTerminator();
/// getLastNonDebugInstr - returns an iterator to the last non-debug
/// instruction in the basic block, or end()
iterator getLastNonDebugInstr();
+ const_iterator getLastNonDebugInstr() const;
/// SplitCriticalEdge - Split the critical edge from this block to the
/// given successor block, and return the newly created block, or null
void pop_front() { Insts.pop_front(); }
void pop_back() { Insts.pop_back(); }
void push_back(MachineInstr *MI) { Insts.push_back(MI); }
+
+ /// Insert MI into the instruction list before I, possibly inside a bundle.
+ ///
+ /// If the insertion point is inside a bundle, MI will be added to the bundle,
+ /// otherwise MI will not be added to any bundle. That means this function
+ /// alone can't be used to prepend or append instructions to bundles. See
+ /// MIBundleBuilder::insert() for a more reliable way of doing that.
+ instr_iterator insert(instr_iterator I, MachineInstr *M);
+
+ /// Insert a range of instructions into the instruction list before I.
template<typename IT>
- void insert(iterator I, IT S, IT E) { Insts.insert(I, S, E); }
- iterator insert(iterator I, MachineInstr *M) { return Insts.insert(I, M); }
- iterator insertAfter(iterator I, MachineInstr *M) {
- return Insts.insertAfter(I, M);
+ void insert(iterator I, IT S, IT E) {
+ Insts.insert(I.getInstrIterator(), S, E);
}
- // erase - Remove the specified element or range from the instruction list.
- // These functions delete any instructions removed.
- //
- iterator erase(iterator I) { return Insts.erase(I); }
- iterator erase(iterator I, iterator E) { return Insts.erase(I, E); }
- 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);
+ /// Insert MI into the instruction list before I.
+ iterator insert(iterator I, MachineInstr *MI) {
+ assert(!MI->isBundledWithPred() && !MI->isBundledWithSucc() &&
+ "Cannot insert instruction with bundle flags");
+ return Insts.insert(I.getInstrIterator(), MI);
}
- /// 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);
+ /// Insert MI into the instruction list after I.
+ iterator insertAfter(iterator I, MachineInstr *MI) {
+ assert(!MI->isBundledWithPred() && !MI->isBundledWithSucc() &&
+ "Cannot insert instruction with bundle flags");
+ return Insts.insertAfter(I.getInstrIterator(), MI);
+ }
+
+ /// Remove an instruction from the instruction list and delete it.
+ ///
+ /// If the instruction is part of a bundle, the other instructions in the
+ /// bundle will still be bundled after removing the single instruction.
+ instr_iterator erase(instr_iterator I);
+
+ /// Remove an instruction from the instruction list and delete it.
+ ///
+ /// If the instruction is part of a bundle, the other instructions in the
+ /// bundle will still be bundled after removing the single instruction.
+ instr_iterator erase_instr(MachineInstr *I) {
+ return erase(instr_iterator(I));
+ }
+
+ /// Remove a range of instructions from the instruction list and delete them.
+ iterator erase(iterator I, iterator E) {
+ return Insts.erase(I.getInstrIterator(), E.getInstrIterator());
+ }
+
+ /// Remove an instruction or bundle from the instruction list and delete it.
+ ///
+ /// If I points to a bundle of instructions, they are all erased.
+ iterator erase(iterator I) {
+ return erase(I, llvm::next(I));
+ }
+
+ /// Remove an instruction from the instruction list and delete it.
+ ///
+ /// If I is the head of a bundle of instructions, the whole bundle will be
+ /// erased.
+ iterator erase(MachineInstr *I) {
+ return erase(iterator(I));
+ }
+
+ /// Remove the unbundled instruction from the instruction list without
+ /// deleting it.
+ ///
+ /// This function can not be used to remove bundled instructions, use
+ /// remove_instr to remove individual instructions from a bundle.
+ MachineInstr *remove(MachineInstr *I) {
+ assert(!I->isBundled() && "Cannot remove bundled instructions");
+ return Insts.remove(I);
+ }
+
+ /// Remove the possibly bundled instruction from the instruction list
+ /// without deleting it.
+ ///
+ /// If the instruction is part of a bundle, the other instructions in the
+ /// bundle will still be bundled after removing the single instruction.
+ MachineInstr *remove_instr(MachineInstr *I);
+
+ void clear() {
+ Insts.clear();
+ }
+
+ /// Take an instruction from MBB 'Other' at the position From, and insert it
+ /// into this MBB right before 'Where'.
+ ///
+ /// If From points to a bundle of instructions, the whole bundle is moved.
+ void splice(iterator Where, MachineBasicBlock *Other, iterator From) {
+ // The range splice() doesn't allow noop moves, but this one does.
+ if (Where != From)
+ splice(Where, Other, From, llvm::next(From));
+ }
+
+ /// Take a block of instructions from MBB 'Other' in the range [From, To),
+ /// and insert them into this MBB right before 'Where'.
+ ///
+ /// The instruction at 'Where' must not be included in the range of
+ /// instructions to move.
+ void splice(iterator Where, MachineBasicBlock *Other,
+ iterator From, iterator To) {
+ Insts.splice(Where.getInstrIterator(), Other->Insts,
+ From.getInstrIterator(), To.getInstrIterator());
}
/// 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();
/// 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);
+ DebugLoc findDebugLoc(instr_iterator MBBI);
+ DebugLoc findDebugLoc(iterator MBBI) {
+ return findDebugLoc(MBBI.getInstrIterator());
+ }
+
+ /// Possible outcome of a register liveness query to computeRegisterLiveness()
+ enum LivenessQueryResult {
+ LQR_Live, ///< Register is known to be live.
+ LQR_OverlappingLive, ///< Register itself is not live, but some overlapping
+ ///< register is.
+ LQR_Dead, ///< Register is known to be dead.
+ LQR_Unknown ///< Register liveness not decidable from local
+ ///< neighborhood.
+ };
+
+ /// computeRegisterLiveness - Return whether (physical) register \c Reg
+ /// has been <def>ined and not <kill>ed as of just before \c MI.
+ ///
+ /// Search is localised to a neighborhood of
+ /// \c Neighborhood instructions before (searching for defs or kills) and
+ /// Neighborhood instructions after (searching just for defs) MI.
+ ///
+ /// \c Reg must be a physical register.
+ LivenessQueryResult computeRegisterLiveness(const TargetRegisterInfo *TRI,
+ unsigned Reg, MachineInstr *MI,
+ unsigned Neighborhood=10);
// Debugging methods.
void dump() const;
/// getSymbol - Return the MCSymbol for this basic block.
///
MCSymbol *getSymbol() const;
-
-private: // Methods used to maintain doubly linked list of blocks...
+
+
+private:
+ /// getWeightIterator - Return weight iterator corresponding to the I
+ /// successor iterator.
+ weight_iterator getWeightIterator(succ_iterator I);
+ const_weight_iterator getWeightIterator(const_succ_iterator I) const;
+
+ friend class MachineBranchProbabilityInfo;
+
+ /// getSuccWeight - Return weight of the edge from this block to MBB. This
+ /// method should NOT be called directly, but by using getEdgeWeight method
+ /// from MachineBranchProbabilityInfo class.
+ uint32_t getSuccWeight(const_succ_iterator Succ) const;
+
+
+ // Methods used to maintain doubly linked list of blocks...
friend struct ilist_traits<MachineBasicBlock>;
// Machine-CFG mutators
void WriteAsOperand(raw_ostream &, const MachineBasicBlock*, bool t);
+// This is useful when building IndexedMaps keyed on basic block pointers.
+struct MBB2NumberFunctor :
+ public std::unary_function<const MachineBasicBlock*, unsigned> {
+ unsigned operator()(const MachineBasicBlock *MBB) const {
+ return MBB->getNumber();
+ }
+};
+
//===--------------------------------------------------------------------===//
// GraphTraits specializations for machine basic block graphs (machine-CFGs)
//===--------------------------------------------------------------------===//