EXTRACT_SUBREG coalescing support. The coalescer now treats EXTRACT_SUBREG like
[oota-llvm.git] / include / llvm / CodeGen / LiveIntervalAnalysis.h
index f7f4569cb3518b05f08268bd8311d03642bf8014..bf0a8295d5fad0f8a1222609d69194a09740abdc 100644 (file)
 #ifndef LLVM_CODEGEN_LIVEINTERVAL_ANALYSIS_H
 #define LLVM_CODEGEN_LIVEINTERVAL_ANALYSIS_H
 
-#include "llvm/ADT/DenseMap.h"
 #include "llvm/CodeGen/MachineFunctionPass.h"
-#include "LiveInterval.h"
+#include "llvm/CodeGen/LiveInterval.h"
+#include "llvm/ADT/BitVector.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/IndexedMap.h"
+#include "llvm/ADT/SmallPtrSet.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Support/Allocator.h"
 
 namespace llvm {
 
   class LiveVariables;
   class MRegisterInfo;
   class TargetInstrInfo;
+  class TargetRegisterClass;
   class VirtRegMap;
 
   class LiveIntervals : public MachineFunctionPass {
@@ -38,6 +44,14 @@ namespace llvm {
     const TargetInstrInfo* tii_;
     LiveVariables* lv_;
 
+    /// Special pool allocator for VNInfo's (LiveInterval val#).
+    ///
+    BumpPtrAllocator VNInfoAllocator;
+
+    /// MBB2IdxMap - The indexes of the first and last instructions in the
+    /// specified basic block.
+    std::vector<std::pair<unsigned, unsigned> > MBB2IdxMap;
+
     typedef std::map<MachineInstr*, unsigned> Mi2IndexMap;
     Mi2IndexMap mi2iMap_;
 
@@ -47,20 +61,21 @@ namespace llvm {
     typedef std::map<unsigned, LiveInterval> Reg2IntervalMap;
     Reg2IntervalMap r2iMap_;
 
-    typedef DenseMap<unsigned> Reg2RegMap;
-    Reg2RegMap r2rMap_;
+    BitVector allocatableRegs_;
 
-    std::vector<bool> allocatableRegs_;
+    std::vector<MachineInstr*> ClonedMIs;
 
   public:
-    struct InstrSlots
-    {
+    static char ID; // Pass identification, replacement for typeid
+    LiveIntervals() : MachineFunctionPass((intptr_t)&ID) {}
+
+    struct InstrSlots {
       enum {
         LOAD  = 0,
         USE   = 1,
         DEF   = 2,
         STORE = 3,
-        NUM   = 4,
+        NUM   = 4
       };
     };
 
@@ -103,6 +118,30 @@ namespace llvm {
       return I->second;
     }
 
+    bool hasInterval(unsigned reg) const {
+      return r2iMap_.count(reg);
+    }
+
+    /// getMBBStartIdx - Return the base index of the first instruction in the
+    /// specified MachineBasicBlock.
+    unsigned getMBBStartIdx(MachineBasicBlock *MBB) const {
+      return getMBBStartIdx(MBB->getNumber());
+    }
+    unsigned getMBBStartIdx(unsigned MBBNo) const {
+      assert(MBBNo < MBB2IdxMap.size() && "Invalid MBB number!");
+      return MBB2IdxMap[MBBNo].first;
+    }
+
+    /// getMBBEndIdx - Return the store index of the last instruction in the
+    /// specified MachineBasicBlock.
+    unsigned getMBBEndIdx(MachineBasicBlock *MBB) const {
+      return getMBBEndIdx(MBB->getNumber());
+    }
+    unsigned getMBBEndIdx(unsigned MBBNo) const {
+      assert(MBBNo < MBB2IdxMap.size() && "Invalid MBB number!");
+      return MBB2IdxMap[MBBNo].second;
+    }
+
     /// getInstructionIndex - returns the base index of instr
     unsigned getInstructionIndex(MachineInstr* instr) const {
       Mi2IndexMap::const_iterator it = mi2iMap_.find(instr);
@@ -119,9 +158,43 @@ namespace llvm {
       return i2miMap_[index];
     }
 
+    // Interval creation
+
+    LiveInterval &getOrCreateInterval(unsigned reg) {
+      Reg2IntervalMap::iterator I = r2iMap_.find(reg);
+      if (I == r2iMap_.end())
+        I = r2iMap_.insert(I, std::make_pair(reg, createInterval(reg)));
+      return I->second;
+    }
+
     std::vector<LiveInterval*> addIntervalsForSpills(const LiveInterval& i,
-                                                     VirtRegMap& vrm,
-                                                     int slot);
+                                                 VirtRegMap& vrm, unsigned reg);
+
+    // Interval removal
+
+    void removeInterval(unsigned Reg) {
+      r2iMap_.erase(Reg);
+    }
+
+    /// isRemoved - returns true if the specified machine instr has been
+    /// removed.
+    bool isRemoved(MachineInstr* instr) const {
+      return !mi2iMap_.count(instr);
+    }
+
+    /// RemoveMachineInstrFromMaps - This marks the specified machine instr as
+    /// deleted.
+    void RemoveMachineInstrFromMaps(MachineInstr *MI) {
+      // remove index -> MachineInstr and
+      // MachineInstr -> index mappings
+      Mi2IndexMap::iterator mi2i = mi2iMap_.find(MI);
+      if (mi2i != mi2iMap_.end()) {
+        i2miMap_[mi2i->second/InstrSlots::NUM] = 0;
+        mi2iMap_.erase(mi2i);
+      }
+    }
+
+    BumpPtrAllocator& getVNInfoAllocator() { return VNInfoAllocator; }
 
     virtual void getAnalysisUsage(AnalysisUsage &AU) const;
     virtual void releaseMemory();
@@ -131,65 +204,56 @@ namespace llvm {
 
     /// print - Implement the dump method.
     virtual void print(std::ostream &O, const Module* = 0) const;
+    void print(std::ostream *O, const Module* M = 0) const {
+      if (O) print(*O, M);
+    }
 
-  private:
-    /// computeIntervals - compute live intervals
+  private:      
+    /// computeIntervals - Compute live intervals.
     void computeIntervals();
-
-    /// joinIntervals - join compatible live intervals
-    void joinIntervals();
-
-    /// joinIntervalsInMachineBB - Join intervals based on move
-    /// instructions in the specified basic block.
-    void joinIntervalsInMachineBB(MachineBasicBlock *MBB);
-
+    
     /// handleRegisterDef - update intervals for a register def
     /// (calls handlePhysicalRegisterDef and
     /// handleVirtualRegisterDef)
-    void handleRegisterDef(MachineBasicBlock* mbb,
-                           MachineBasicBlock::iterator mi,
+    void handleRegisterDef(MachineBasicBlock *MBB,
+                           MachineBasicBlock::iterator MI, unsigned MIIdx,
                            unsigned reg);
 
     /// handleVirtualRegisterDef - update intervals for a virtual
     /// register def
-    void handleVirtualRegisterDef(MachineBasicBlock* mbb,
-                                  MachineBasicBlock::iterator mi,
+    void handleVirtualRegisterDef(MachineBasicBlock *MBB,
+                                  MachineBasicBlock::iterator MI,
+                                  unsigned MIIdx,
                                   LiveInterval& interval);
 
     /// handlePhysicalRegisterDef - update intervals for a physical register
-    /// def.  If the defining instruction is a move instruction, SrcReg will be
-    /// the input register, and DestReg will be the result.  Note that Interval
-    /// may not match DestReg (it might be an alias instead).
-    ///
+    /// def.
     void handlePhysicalRegisterDef(MachineBasicBlock* mbb,
                                    MachineBasicBlock::iterator mi,
-                                   LiveInterval& interval,
-                                   unsigned SrcReg, unsigned DestReg);
-
-    /// Return true if the two specified registers belong to different
-    /// register classes.  The registers may be either phys or virt regs.
-    bool differingRegisterClasses(unsigned RegA, unsigned RegB) const;
-
-    bool overlapsAliases(const LiveInterval *lhs,
-                         const LiveInterval *rhs) const;
+                                   unsigned MIIdx,
+                                   LiveInterval &interval,
+                                   unsigned SrcReg);
+
+    /// handleLiveInRegister - Create interval for a livein register.
+    void handleLiveInRegister(MachineBasicBlock* mbb,
+                              unsigned MIIdx,
+                              LiveInterval &interval, bool isAlias = false);
+
+    /// isReMaterializable - Returns true if the definition MI of the specified
+    /// val# of the specified interval is re-materializable.
+    bool isReMaterializable(const LiveInterval &li, const VNInfo *ValNo,
+                            MachineInstr *MI);
+
+    /// tryFoldMemoryOperand - Attempts to fold either a spill / restore from
+    /// slot / to reg or any rematerialized load into ith operand of specified
+    /// MI. If it is successul, MI is updated with the newly created MI and
+    /// returns true.
+    bool tryFoldMemoryOperand(MachineInstr* &MI, VirtRegMap &vrm,
+                              MachineInstr *DefMI, unsigned index, unsigned i,
+                              bool isSS, int slot, unsigned reg);
 
     static LiveInterval createInterval(unsigned Reg);
 
-    LiveInterval &getOrCreateInterval(unsigned reg) {
-      Reg2IntervalMap::iterator I = r2iMap_.find(reg);
-      if (I == r2iMap_.end())
-        I = r2iMap_.insert(I, std::make_pair(reg, createInterval(reg)));
-      return I->second;
-    }
-
-    /// rep - returns the representative of this register
-    unsigned rep(unsigned Reg) {
-      unsigned Rep = r2rMap_[Reg];
-      if (Rep)
-        return r2rMap_[Reg] = rep(Rep);
-      return Reg;
-    }
-
     void printRegName(unsigned reg) const;
   };