X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FCodeGen%2FSimpleRegisterCoalescing.h;h=330c476dbf5a92bf1a301feac2718589706f15f3;hb=f9410141f703f4e8a6aba717617ef958249f6d13;hp=5b3d6b67a91b8291f3adb9eddaeadf30c3e009f4;hpb=9c1e06e18721206c736512f3448997b41145019c;p=oota-llvm.git

diff --git a/lib/CodeGen/SimpleRegisterCoalescing.h b/lib/CodeGen/SimpleRegisterCoalescing.h
index 5b3d6b67a91..330c476dbf5 100644
--- a/lib/CodeGen/SimpleRegisterCoalescing.h
+++ b/lib/CodeGen/SimpleRegisterCoalescing.h
@@ -83,7 +83,6 @@ namespace llvm {
     const TargetRegisterInfo* tri_;
     const TargetInstrInfo* tii_;
     LiveIntervals *li_;
-    LiveVariables *lv_;
     const MachineLoopInfo* loopInfo;
     
     BitVector allocatableRegs_;
@@ -97,9 +96,17 @@ namespace llvm {
     ///
     SmallPtrSet<MachineInstr*, 32> JoinedCopies;
 
+    /// ReMatCopies - Keep track of copies eliminated due to remat.
+    ///
+    SmallPtrSet<MachineInstr*, 32> ReMatCopies;
+
+    /// ReMatDefs - Keep track of definition instructions which have
+    /// been remat'ed.
+    SmallPtrSet<MachineInstr*, 8> ReMatDefs;
+
   public:
     static char ID; // Pass identifcation, replacement for typeid
-    SimpleRegisterCoalescing() : MachineFunctionPass((intptr_t)&ID) {}
+    SimpleRegisterCoalescing() : MachineFunctionPass(&ID) {}
 
     struct InstrSlots {
       enum {
@@ -127,7 +134,8 @@ namespace llvm {
     unsigned getRepIntervalSize(unsigned Reg) {
       if (!li_->hasInterval(Reg))
         return 0;
-      return li_->getInterval(Reg).getSize();
+      return li_->getApproximateInstructionCount(li_->getInterval(Reg)) *
+             LiveIntervals::InstrSlots::NUM;
     }
 
     /// print - Implement the dump method.
@@ -166,9 +174,13 @@ namespace llvm {
     /// joins them and returns true.
     bool SimpleJoin(LiveInterval &LHS, LiveInterval &RHS);
     
-    /// Return true if the two specified registers belong to different
-    /// register classes.  The registers may be either phys or virt regs.
-    bool differingRegisterClasses(unsigned RegA, unsigned RegB) const;
+    /// Return true if the two specified registers belong to different register
+    /// classes.  The registers may be either phys or virt regs. In the
+    /// case where both registers are virtual registers, it would also returns
+    /// true by reference the RegB register class in SubRC if it is a subset of
+    /// RegA's register class.
+    bool differingRegisterClasses(unsigned RegA, unsigned RegB,
+                                  const TargetRegisterClass *&SubRC) const;
 
 
     /// AdjustCopiesBackFrom - We found a non-trivially-coalescable copy. If
@@ -190,6 +202,9 @@ namespace llvm {
     bool RemoveCopyByCommutingDef(LiveInterval &IntA, LiveInterval &IntB,
                                   MachineInstr *CopyMI);
 
+    bool ReMaterializeTrivialDef(LiveInterval &SrcInt, unsigned DstReg,
+                                 MachineInstr *CopyMI);
+
     /// TurnCopyIntoImpDef - If source of the specified copy is an implicit def,
     /// turn the copy into an implicit def.
     bool TurnCopyIntoImpDef(MachineBasicBlock::iterator &I,
@@ -206,6 +221,19 @@ namespace llvm {
     /// identity copies so they will be removed.
     void RemoveCopiesFromValNo(LiveInterval &li, VNInfo *VNI);
 
+    /// isProfitableToCoalesceToSubRC - Given that register class of DstReg is
+    /// a subset of the register class of SrcReg, return true if it's profitable
+    /// to coalesce the two registers.
+    bool isProfitableToCoalesceToSubRC(unsigned SrcReg, unsigned DstReg,
+                                       MachineBasicBlock *MBB);
+
+    /// HasIncompatibleSubRegDefUse - If we are trying to coalesce a virtual
+    /// register with a physical register, check if any of the virtual register
+    /// operand is a sub-register use or def. If so, make sure it won't result
+    /// in an illegal extract_subreg or insert_subreg instruction.
+    bool HasIncompatibleSubRegDefUse(MachineInstr *CopyMI,
+                                     unsigned VirtReg, unsigned PhysReg);
+
     /// RangeIsDefinedByCopyFromReg - Return true if the specified live range of
     /// the specified live interval is defined by a copy from the specified
     /// register.