Inline check that's used only once.

[oota-llvm.git] / lib / CodeGen / LiveRangeEdit.h

diff --git a/lib/CodeGen/LiveRangeEdit.h b/lib/CodeGen/LiveRangeEdit.h
index 73f69ed639836a1eef47772c502cec49ef4fa71b..04eced6d79b7d59bc659285422a08327e75dd42b 100644 (file)
--- a/lib/CodeGen/LiveRangeEdit.h
+++ b/lib/CodeGen/LiveRangeEdit.h
@@ -29,9 +29,27 @@ class MachineRegisterInfo;
 class VirtRegMap;
 
 class LiveRangeEdit {
+public:
+  /// Callback methods for LiveRangeEdit owners.
+  struct Delegate {
+    /// Called immediately before erasing a dead machine instruction.
+    virtual void LRE_WillEraseInstruction(MachineInstr *MI) {}
+
+    /// Called when a virtual register is no longer used. Return false to defer
+    /// its deletion from LiveIntervals.
+    virtual bool LRE_CanEraseVirtReg(unsigned) { return true; }
+
+    /// Called before shrinking the live range of a virtual register.
+    virtual void LRE_WillShrinkVirtReg(unsigned) {}
+
+    virtual ~Delegate() {}
+  };
+
+private:
   LiveInterval &parent_;
   SmallVectorImpl<LiveInterval*> &newRegs_;
-  const SmallVectorImpl<LiveInterval*> &uselessRegs_;
+  Delegate *const delegate_;
+  const SmallVectorImpl<LiveInterval*> *uselessRegs_;
 
   /// firstNew_ - Index of the first register added to newRegs_.
   const unsigned firstNew_;
@@ -41,11 +59,11 @@ class LiveRangeEdit {
 
   /// remattable_ - Values defined by remattable instructions as identified by
   /// tii.isTriviallyReMaterializable().
-  SmallPtrSet<VNInfo*,4> remattable_;
+  SmallPtrSet<const VNInfo*,4> remattable_;
 
   /// rematted_ - Values that were actually rematted, and so need to have their
   /// live range trimmed or entirely removed.
-  SmallPtrSet<VNInfo*,4> rematted_;
+  SmallPtrSet<const VNInfo*,4> rematted_;
 
   /// scanRemattable - Identify the parent_ values that may rematerialize.
   void scanRemattable(LiveIntervals &lis,
@@ -66,9 +84,13 @@ public:
   ///        rematerializing values because they are about to be removed.
   LiveRangeEdit(LiveInterval &parent,
                 SmallVectorImpl<LiveInterval*> &newRegs,
-                const SmallVectorImpl<LiveInterval*> &uselessRegs)
-    : parent_(parent), newRegs_(newRegs), uselessRegs_(uselessRegs),
-      firstNew_(newRegs.size()), scannedRemattable_(false) {}
+                Delegate *delegate = 0,
+                const SmallVectorImpl<LiveInterval*> *uselessRegs = 0)
+    : parent_(parent), newRegs_(newRegs),
+      delegate_(delegate),
+      uselessRegs_(uselessRegs),
+      firstNew_(newRegs.size()),
+      scannedRemattable_(false) {}
 
   LiveInterval &getParent() const { return parent_; }
   unsigned getReg() const { return parent_.reg; }
@@ -81,16 +103,33 @@ public:
   bool empty() const { return size() == 0; }
   LiveInterval *get(unsigned idx) const { return newRegs_[idx+firstNew_]; }
 
-  /// create - Create a new register with the same class and stack slot as
+  /// FIXME: Temporary accessors until we can get rid of
+  /// LiveIntervals::AddIntervalsForSpills
+  SmallVectorImpl<LiveInterval*> *getNewVRegs() { return &newRegs_; }
+  const SmallVectorImpl<LiveInterval*> *getUselessVRegs() {
+    return uselessRegs_;
+  }
+
+  /// createFrom - Create a new virtual register based on OldReg.
+  LiveInterval &createFrom(unsigned OldReg, LiveIntervals&, VirtRegMap&);
+
+  /// create - Create a new register with the same class and original slot as
   /// parent.
-  LiveInterval &create(MachineRegisterInfo&, LiveIntervals&, VirtRegMap&);
+  LiveInterval &create(LiveIntervals &LIS, VirtRegMap &VRM) {
+    return createFrom(getReg(), LIS, VRM);
+  }
 
   /// anyRematerializable - Return true if any parent values may be
   /// rematerializable.
-  /// This function must be called before ny rematerialization is attempted.
+  /// This function must be called before any rematerialization is attempted.
   bool anyRematerializable(LiveIntervals&, const TargetInstrInfo&,
                            AliasAnalysis*);
 
+  /// checkRematerializable - Manually add VNI to the list of rematerializable
+  /// values if DefMI may be rematerializable.
+  void checkRematerializable(VNInfo *VNI, const MachineInstr *DefMI,
+                             const TargetInstrInfo&, AliasAnalysis*);
+
   /// Remat - Information needed to rematerialize at a specific location.
   struct Remat {
     VNInfo *ParentVNI;      // parent_'s value at the remat location.
@@ -120,14 +159,26 @@ public:
 
   /// markRematerialized - explicitly mark a value as rematerialized after doing
   /// it manually.
-  void markRematerialized(VNInfo *ParentVNI) {
+  void markRematerialized(const VNInfo *ParentVNI) {
     rematted_.insert(ParentVNI);
   }
 
   /// didRematerialize - Return true if ParentVNI was rematerialized anywhere.
-  bool didRematerialize(VNInfo *ParentVNI) const {
+  bool didRematerialize(const VNInfo *ParentVNI) const {
     return rematted_.count(ParentVNI);
   }
+
+  /// eraseVirtReg - Notify the delegate that Reg is no longer in use, and try
+  /// to erase it from LIS.
+  void eraseVirtReg(unsigned Reg, LiveIntervals &LIS);
+
+  /// eliminateDeadDefs - Try to delete machine instructions that are now dead
+  /// (allDefsAreDead returns true). This may cause live intervals to be trimmed
+  /// and further dead efs to be eliminated.
+  void eliminateDeadDefs(SmallVectorImpl<MachineInstr*> &Dead,
+                         LiveIntervals&, VirtRegMap&,
+                         const TargetInstrInfo&);
+
 };
 
 }