Store (priority,regnum) pairs in the priority queue instead of providing an

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

diff --git a/lib/CodeGen/RegAllocBase.h b/lib/CodeGen/RegAllocBase.h
index 7f38c9b95a974ff6b744941aa2b18d3458ae8889..65bec06c712ab54645c7f332b8859eaa2d23609d 100644 (file)
--- a/lib/CodeGen/RegAllocBase.h
+++ b/lib/CodeGen/RegAllocBase.h
@@ -39,6 +39,7 @@
 
 #include "llvm/ADT/OwningPtr.h"
 #include "LiveIntervalUnion.h"
+#include <queue>
 
 namespace llvm {
 
@@ -48,16 +49,6 @@ class VirtRegMap;
 class LiveIntervals;
 class Spiller;
 
-// Heuristic that determines the priority of assigning virtual to physical
-// registers. The main impact of the heuristic is expected to be compile time.
-// The default is to simply compare spill weights.
-struct LessSpillWeightPriority
-  : public std::binary_function<LiveInterval,LiveInterval, bool> {
-  bool operator()(const LiveInterval *Left, const LiveInterval *Right) const {
-    return Left->weight < Right->weight;
-  }
-};
-
 // Forward declare a priority queue of live virtual registers. If an
 // implementation needs to prioritize by anything other than spill weight, then
 // this will become an abstract base class with virtual calls to push/get.
@@ -128,6 +119,10 @@ protected:
   // Get a temporary reference to a Spiller instance.
   virtual Spiller &spiller() = 0;
 
+  // getPriority - Calculate the allocation priority for VirtReg.
+  // Virtual registers with higher priorities are allocated first.
+  virtual float getPriority(LiveInterval *LI) = 0;
+
   // A RegAlloc pass should override this to provide the allocation heuristics.
   // Each call must guarantee forward progess by returning an available PhysReg
   // or new set of split live virtual registers. It is up to the splitter to
@@ -158,7 +153,7 @@ protected:
 #endif
 
 private:
-  void seedLiveVirtRegs(LiveVirtRegQueue &VirtRegQ);
+  void seedLiveVirtRegs(std::priority_queue<std::pair<float, unsigned> >&);
 
   void spillReg(LiveInterval &VirtReg, unsigned PhysReg,
                 SmallVectorImpl<LiveInterval*> &SplitVRegs);