Code to insert caller-saves moved here from SparcRegInfo: it is now

machine-independent.
Fix problem with using branch operand reg. as temp. reg. when
spilling values used by an instruction in the delay slot of the branch
(which will eventually be moved before the branch).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@7385 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 22 insertions, 9 deletions

diff --git a/lib/Target/SparcV9/RegAlloc/PhyRegAlloc.h b/lib/Target/SparcV9/RegAlloc/PhyRegAlloc.h
index dc7772e..6790acd 100644
--- a/lib/Target/SparcV9/RegAlloc/PhyRegAlloc.h
+++ b/lib/Target/SparcV9/RegAlloc/PhyRegAlloc.h
@@ -20,6 +20,7 @@
 #define PHY_REG_ALLOC_H
 
 #include "llvm/CodeGen/LiveRangeInfo.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
 #include "Support/NonCopyable.h"
 #include <map>
 
@@ -81,7 +82,6 @@ public:
   //
   void allocateRegisters();           
 
-
   // access to register classes by class ID
   // 
   const RegClass*  getRegClassByID(unsigned int id) const {
@@ -90,7 +90,7 @@ public:
   RegClass*  getRegClassByID(unsigned int id) {
     return RegClassList[id];
   }
-  
+
 private:
   void addInterference(const Value *Def, const ValueSet *LVSet, 
 		       bool isCallInst);
@@ -109,32 +109,45 @@ private:
   void allocateStackSpace4SpilledLRs();
 
   void insertCode4SpilledLR     (const LiveRange *LR, 
-                                 MachineInstr *MInst,
-                                 const BasicBlock *BB,
+                                 MachineBasicBlock::iterator& MII,
+                                 MachineBasicBlock &MBB,
                                  const unsigned OpNum);
 
+  // Method for inserting caller saving code. The caller must save all the
+  // volatile registers live across a call.
+  void insertCallerSavingCode(std::vector<MachineInstr*>& instrnsBefore,
+                              std::vector<MachineInstr*>& instrnsAfter,
+                              MachineInstr *CallMI,
+                              const BasicBlock *BB);
+
   inline void constructLiveRanges() { LRI.constructLiveRanges(); }      
 
   void colorIncomingArgs();
   void colorCallRetArgs();
   void updateMachineCode();
-  void updateInstruction(MachineInstr* MInst, BasicBlock* BB);
+  void updateInstruction(MachineBasicBlock::iterator& MII,
+                         MachineBasicBlock &MBB);
 
   void printLabel(const Value *const Val);
   void printMachineCode();
 
 
-  friend class UltraSparcRegInfo;  // FIXME: remove this
-
   int getUsableUniRegAtMI(int RegType, 
 			  const ValueSet *LVSetBef,
 			  MachineInstr *MInst,
                           std::vector<MachineInstr*>& MIBef,
                           std::vector<MachineInstr*>& MIAft);
   
+  // Callback method used to find unused registers. 
+  // LVSetBef is the live variable set to search for an unused register.
+  // If it is not specified, the LV set before the current MInst is used.
+  // This is sufficient as long as no new copy instructions are generated
+  // to copy the free register to memory.
+  // 
   int getUnusedUniRegAtMI(RegClass *RC, const int RegType,
-                          const MachineInstr *MInst, const ValueSet *LVSetBef);
-
+                          const MachineInstr *MInst,
+                          const ValueSet *LVSetBef = 0);
+  
   void setRelRegsUsedByThisInst(RegClass *RC, const int RegType,
                                 const MachineInstr *MInst );