X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FCodeGen%2FRegisterScavenging.h;h=6604d4cddaae2e1cc2f37ab326974f9467fb324e;hb=69261a644298bff1497d46c8cd38d688670f307b;hp=246831c034d4c5f4781b735b9da6a6105d135eef;hpb=b113cf2fedaf290242939c8f8c6f7e1438d46024;p=oota-llvm.git

diff --git a/include/llvm/CodeGen/RegisterScavenging.h b/include/llvm/CodeGen/RegisterScavenging.h
index 246831c034d..6604d4cddaa 100644
--- a/include/llvm/CodeGen/RegisterScavenging.h
+++ b/include/llvm/CodeGen/RegisterScavenging.h
@@ -17,8 +17,9 @@
 #ifndef LLVM_CODEGEN_REGISTER_SCAVENGING_H
 #define LLVM_CODEGEN_REGISTER_SCAVENGING_H
 
-#include "llvm/CodeGen/MachineBasicBlock.h"
 #include "llvm/ADT/BitVector.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
 
 namespace llvm {
 
@@ -59,15 +60,15 @@ class RegScavenger {
   ///
   BitVector CalleeSavedRegs;
 
-  /// ReservedRegs - A bitvector of reserved registers.
-  ///
-  BitVector ReservedRegs;
-
   /// RegsAvailable - The current state of all the physical registers immediately
   /// before MBBI. One bit per physical register. If bit is set that means it's
   /// available, unset means the register is currently being used.
   BitVector RegsAvailable;
 
+  // These BitVectors are only used internally to forward(). They are members
+  // to avoid frequent reallocations.
+  BitVector KillRegs, DefRegs;
+
 public:
   RegScavenger()
     : MBB(NULL), NumPhysRegs(0), Tracking(false),
@@ -100,7 +101,7 @@ public:
 
   /// getRegsAvailable - Return all available registers in the register class
   /// in Mask.
-  void getRegsAvailable(const TargetRegisterClass *RC, BitVector &Mask);
+  BitVector getRegsAvailable(const TargetRegisterClass *RC);
 
   /// FindUnusedReg - Find a unused register of the specified register class.
   /// Return 0 if none is found.
@@ -126,12 +127,15 @@ public:
   void setUsed(unsigned Reg);
 private:
   /// isReserved - Returns true if a register is reserved. It is never "unused".
-  bool isReserved(unsigned Reg) const { return ReservedRegs.test(Reg); }
+  bool isReserved(unsigned Reg) const { return MRI->isReserved(Reg); }
 
-  /// isUsed / isUnused - Test if a register is currently being used.
+  /// isUsed - Test if a register is currently being used.  When called by the
+  /// isAliasUsed function, we only check isReserved if this is the original
+  /// register, not an alias register.
   ///
-  bool isUsed(unsigned Reg) const   { return !RegsAvailable.test(Reg); }
-  bool isUnused(unsigned Reg) const { return RegsAvailable.test(Reg); }
+  bool isUsed(unsigned Reg, bool CheckReserved = true) const   {
+    return !RegsAvailable.test(Reg) || (CheckReserved && isReserved(Reg));
+  }
 
   /// isAliasUsed - Is Reg or an alias currently in use?
   bool isAliasUsed(unsigned Reg) const;
@@ -139,7 +143,7 @@ private:
   /// setUsed / setUnused - Mark the state of one or a number of registers.
   ///
   void setUsed(BitVector &Regs) {
-    RegsAvailable &= ~Regs;
+    RegsAvailable.reset(Regs);
   }
   void setUnused(BitVector &Regs) {
     RegsAvailable |= Regs;
@@ -148,9 +152,6 @@ private:
   /// Add Reg and all its sub-registers to BV.
   void addRegWithSubRegs(BitVector &BV, unsigned Reg);
 
-  /// Add Reg and its aliases to BV.
-  void addRegWithAliases(BitVector &BV, unsigned Reg);
-
   /// findSurvivorReg - Return the candidate register that is unused for the
   /// longest after StartMI. UseMI is set to the instruction where the search
   /// stopped.