Recommit r129383. PreRA scheduler heuristic fixes: VRegCycle, TokenFactor latency.

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

diff --git a/lib/CodeGen/LiveIntervalUnion.h b/lib/CodeGen/LiveIntervalUnion.h
index ff23cf61a3338c16a5d47d5acf54bf1ea569f5d2..c83578e99c6ca5f611e9bcc4c68a192ae4f2b265 100644 (file)
--- a/lib/CodeGen/LiveIntervalUnion.h
+++ b/lib/CodeGen/LiveIntervalUnion.h
@@ -64,10 +64,12 @@ public:
 
 private:
   const unsigned RepReg;  // representative register number
+  unsigned Tag;           // unique tag for current contents.
   LiveSegments Segments;  // union of virtual reg segments
 
 public:
-  LiveIntervalUnion(unsigned r, Allocator &a) : RepReg(r), Segments(a) {}
+  LiveIntervalUnion(unsigned r, Allocator &a) : RepReg(r), Tag(0), Segments(a)
+    {}
 
   // Iterate over all segments in the union of live virtual registers ordered
   // by their starting position.
@@ -81,12 +83,21 @@ public:
   typedef LiveSegments Map;
   const Map &getMap() { return Segments; }
 
+  /// getTag - Return an opaque tag representing the current state of the union.
+  unsigned getTag() const { return Tag; }
+
+  /// changedSince - Return true if the union change since getTag returned tag.
+  bool changedSince(unsigned tag) const { return tag != Tag; }
+
   // Add a live virtual register to this union and merge its segments.
   void unify(LiveInterval &VirtReg);
 
   // Remove a live virtual register's segments from this union.
   void extract(LiveInterval &VirtReg);
 
+  // Remove all inserted virtual registers.
+  void clear() { Segments.clear(); ++Tag; }
+
   // Print union, using TRI to translate register names
   void print(raw_ostream &OS, const TargetRegisterInfo *TRI) const;
 
@@ -155,9 +166,10 @@ public:
     bool CheckedFirstInterference;
     bool SeenAllInterferences;
     bool SeenUnspillableVReg;
+    unsigned Tag, UserTag;
 
   public:
-    Query(): LiveUnion(), VirtReg() {}
+    Query(): LiveUnion(), VirtReg(), Tag(0), UserTag(0) {}
 
     Query(LiveInterval *VReg, LiveIntervalUnion *LIU):
       LiveUnion(LIU), VirtReg(VReg), CheckedFirstInterference(false),
@@ -171,17 +183,22 @@ public:
       CheckedFirstInterference = false;
       SeenAllInterferences = false;
       SeenUnspillableVReg = false;
+      Tag = 0;
+      UserTag = 0;
     }
 
-    void init(LiveInterval *VReg, LiveIntervalUnion *LIU) {
+    void init(unsigned UTag, LiveInterval *VReg, LiveIntervalUnion *LIU) {
       assert(VReg && LIU && "Invalid arguments");
-      if (VirtReg == VReg && LiveUnion == LIU) {
+      if (UserTag == UTag && VirtReg == VReg &&
+          LiveUnion == LIU && !LIU->changedSince(Tag)) {
         // Retain cached results, e.g. firstInterference.
         return;
       }
       clear();
       LiveUnion = LIU;
       VirtReg = VReg;
+      Tag = LIU->getTag();
+      UserTag = UTag;
     }
 
     LiveInterval &virtReg() const {
@@ -212,7 +229,8 @@ public:
 
     // Count the virtual registers in this union that interfere with this
     // query's live virtual register, up to maxInterferingRegs.
-    unsigned collectInterferingVRegs(unsigned MaxInterferingRegs = UINT_MAX);
+    unsigned collectInterferingVRegs(unsigned MaxInterferingRegs = UINT_MAX,
+                                     float MaxWeight = HUGE_VALF);
 
     // Was this virtual register visited during collectInterferingVRegs?
     bool isSeenInterference(LiveInterval *VReg) const;