Add some comments explaining what MVT and EVT are, and how they differ.

[oota-llvm.git] / include / llvm / CodeGen / CalcSpillWeights.h

diff --git a/include/llvm/CodeGen/CalcSpillWeights.h b/include/llvm/CodeGen/CalcSpillWeights.h
index 2fc03bd41de8fd5c24a39cc887e6c4877d4ee478..24264d7f97f0e7177df61c911f3924e106c0ceb6 100644 (file)
--- a/include/llvm/CodeGen/CalcSpillWeights.h
+++ b/include/llvm/CodeGen/CalcSpillWeights.h
@@ -12,10 +12,35 @@
 #define LLVM_CODEGEN_CALCSPILLWEIGHTS_H
 
 #include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/ADT/DenseMap.h"
 
 namespace llvm {
 
   class LiveInterval;
+  class LiveIntervals;
+  class MachineLoopInfo;
+
+  /// VirtRegAuxInfo - Calculate auxiliary information for a virtual
+  /// register such as its spill weight and allocation hint.
+  class VirtRegAuxInfo {
+    MachineFunction &mf_;
+    LiveIntervals &lis_;
+    const MachineLoopInfo &loops_;
+    DenseMap<unsigned, float> hint_;
+  public:
+    VirtRegAuxInfo(MachineFunction &mf, LiveIntervals &lis,
+                   const MachineLoopInfo &loops) :
+      mf_(mf), lis_(lis), loops_(loops) {}
+
+    /// CalculateRegClass - recompute the register class for reg from its uses.
+    /// Since the register class can affect the allocation hint, this function
+    /// should be called before CalculateWeightAndHint if both are called.
+    void CalculateRegClass(unsigned reg);
+
+    /// CalculateWeightAndHint - (re)compute li's spill weight and allocation
+    /// hint.
+    void CalculateWeightAndHint(LiveInterval &li);
+  };
 
   /// CalculateSpillWeights - Compute spill weights for all virtual register
   /// live intervals.
@@ -23,11 +48,13 @@ namespace llvm {
   public:
     static char ID;
 
-    CalculateSpillWeights() : MachineFunctionPass(&ID) {}
+    CalculateSpillWeights() : MachineFunctionPass(ID) {
+      initializeCalculateSpillWeightsPass(*PassRegistry::getPassRegistry());
+    }
 
     virtual void getAnalysisUsage(AnalysisUsage &au) const;
 
-    virtual bool runOnMachineFunction(MachineFunction &fn);    
+    virtual bool runOnMachineFunction(MachineFunction &fn);
 
   private:
     /// Returns true if the given live interval is zero length.