Switch most getReservedRegs() clients to the MRI equivalent.

Using the cached bit vector in MRI avoids comstantly allocating and
recomputing the reserved register bit vector.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165983 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 3 insertions, 12 deletions

diff --git a/include/llvm/CodeGen/LiveVariables.h b/include/llvm/CodeGen/LiveVariables.h
index d4bb409e060..3bb134b8fb2 100644
--- a/include/llvm/CodeGen/LiveVariables.h
+++ b/include/llvm/CodeGen/LiveVariables.h
@@ -126,12 +126,6 @@ private:
   /// building live intervals.
   SparseBitVector<> PHIJoins;
 
-  /// ReservedRegisters - This vector keeps track of which registers
-  /// are reserved register which are not allocatable by the target machine.
-  /// We can not track liveness for values that are in this set.
-  ///
-  BitVector ReservedRegisters;
-
 private:   // Intermediate data structures
   MachineFunction *MF;
 
diff --git a/include/llvm/CodeGen/RegisterScavenging.h b/include/llvm/CodeGen/RegisterScavenging.h
index 3986a8dd7da..08d316992ec 100644
--- a/include/llvm/CodeGen/RegisterScavenging.h
+++ b/include/llvm/CodeGen/RegisterScavenging.h
@@ -18,6 +18,7 @@
 #define LLVM_CODEGEN_REGISTER_SCAVENGING_H
 
 #include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
 #include "llvm/ADT/BitVector.h"
 
 namespace llvm {
@@ -59,10 +60,6 @@ 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.
@@ -130,12 +127,12 @@ 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.
   ///
   bool isUsed(unsigned Reg) const   {
-    return !RegsAvailable.test(Reg) || ReservedRegs.test(Reg);
+    return !RegsAvailable.test(Reg) || isReserved(Reg);
   }
 
   /// isAliasUsed - Is Reg or an alias currently in use?