//
//===----------------------------------------------------------------------===//
+#include "RegisterClassInfo.h"
#include "llvm/Support/IncludeFile.h"
#include "llvm/CodeGen/LiveInterval.h"
#include "llvm/ADT/SmallPtrSet.h"
class TargetRegisterInfo;
class TargetRegisterClass;
class TargetInstrInfo;
+ class SimpleRegisterCoalescing;
+ class LiveDebugVariables;
+ class VirtRegMap;
+ class MachineLoopInfo;
/// An abstract interface for register coalescers. Coalescers must
/// implement this interface to be part of the coalescer analysis
/// getNewRC - Return the register class of the coalesced register.
const TargetRegisterClass *getNewRC() const { return newRC_; }
};
-}
+
+ class SimpleRegisterCoalescing : public MachineFunctionPass,
+ public RegisterCoalescer {
+ MachineFunction* mf_;
+ MachineRegisterInfo* mri_;
+ const TargetMachine* tm_;
+ const TargetRegisterInfo* tri_;
+ const TargetInstrInfo* tii_;
+ LiveIntervals *li_;
+ LiveDebugVariables *ldv_;
+ const MachineLoopInfo* loopInfo;
+ AliasAnalysis *AA;
+ RegisterClassInfo RegClassInfo;
+
+ /// JoinedCopies - Keep track of copies eliminated due to coalescing.
+ ///
+ 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(ID) {
+ initializeSimpleRegisterCoalescingPass(*PassRegistry::getPassRegistry());
+ }
+
+ virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+ virtual void releaseMemory();
+
+ /// runOnMachineFunction - pass entry point
+ virtual bool runOnMachineFunction(MachineFunction&);
+
+ bool coalesceFunction(MachineFunction &mf, RegallocQuery &) {
+ // This runs as an independent pass, so don't do anything.
+ return false;
+ }
+
+ /// print - Implement the dump method.
+ virtual void print(raw_ostream &O, const Module* = 0) const;
+
+ private:
+ /// joinIntervals - join compatible live intervals
+ void joinIntervals();
+
+ /// CopyCoalesceInMBB - Coalesce copies in the specified MBB, putting
+ /// copies that cannot yet be coalesced into the "TryAgain" list.
+ void CopyCoalesceInMBB(MachineBasicBlock *MBB,
+ std::vector<MachineInstr*> &TryAgain);
+
+ /// JoinCopy - Attempt to join intervals corresponding to SrcReg/DstReg,
+ /// which are the src/dst of the copy instruction CopyMI. This returns true
+ /// if the copy was successfully coalesced away. If it is not currently
+ /// possible to coalesce this interval, but it may be possible if other
+ /// things get coalesced, then it returns true by reference in 'Again'.
+ bool JoinCopy(MachineInstr *TheCopy, bool &Again);
+
+ /// JoinIntervals - Attempt to join these two intervals. On failure, this
+ /// returns false. The output "SrcInt" will not have been modified, so we can
+ /// use this information below to update aliases.
+ bool JoinIntervals(CoalescerPair &CP);
+
+ /// AdjustCopiesBackFrom - We found a non-trivially-coalescable copy. If
+ /// the source value number is defined by a copy from the destination reg
+ /// see if we can merge these two destination reg valno# into a single
+ /// value number, eliminating a copy.
+ bool AdjustCopiesBackFrom(const CoalescerPair &CP, MachineInstr *CopyMI);
+
+ /// HasOtherReachingDefs - Return true if there are definitions of IntB
+ /// other than BValNo val# that can reach uses of AValno val# of IntA.
+ bool HasOtherReachingDefs(LiveInterval &IntA, LiveInterval &IntB,
+ VNInfo *AValNo, VNInfo *BValNo);
+
+ /// RemoveCopyByCommutingDef - We found a non-trivially-coalescable copy.
+ /// If the source value number is defined by a commutable instruction and
+ /// its other operand is coalesced to the copy dest register, see if we
+ /// can transform the copy into a noop by commuting the definition.
+ bool RemoveCopyByCommutingDef(const CoalescerPair &CP,MachineInstr *CopyMI);
+
+ /// ReMaterializeTrivialDef - If the source of a copy is defined by a trivial
+ /// computation, replace the copy by rematerialize the definition.
+ /// If PreserveSrcInt is true, make sure SrcInt is valid after the call.
+ bool ReMaterializeTrivialDef(LiveInterval &SrcInt, bool PreserveSrcInt,
+ unsigned DstReg, unsigned DstSubIdx,
+ MachineInstr *CopyMI);
+
+ /// shouldJoinPhys - Return true if a physreg copy should be joined.
+ bool shouldJoinPhys(CoalescerPair &CP);
+
+ /// isWinToJoinCrossClass - Return true if it's profitable to coalesce
+ /// two virtual registers from different register classes.
+ bool isWinToJoinCrossClass(unsigned SrcReg,
+ unsigned DstReg,
+ const TargetRegisterClass *SrcRC,
+ const TargetRegisterClass *DstRC,
+ const TargetRegisterClass *NewRC);
+
+ /// UpdateRegDefsUses - Replace all defs and uses of SrcReg to DstReg and
+ /// update the subregister number if it is not zero. If DstReg is a
+ /// physical register and the existing subregister number of the def / use
+ /// being updated is not zero, make sure to set it to the correct physical
+ /// subregister.
+ void UpdateRegDefsUses(const CoalescerPair &CP);
+
+ /// RemoveDeadDef - If a def of a live interval is now determined dead,
+ /// remove the val# it defines. If the live interval becomes empty, remove
+ /// it as well.
+ bool RemoveDeadDef(LiveInterval &li, MachineInstr *DefMI);
+
+ /// RemoveCopyFlag - If DstReg is no longer defined by CopyMI, clear the
+ /// VNInfo copy flag for DstReg and all aliases.
+ void RemoveCopyFlag(unsigned DstReg, const MachineInstr *CopyMI);
+
+ /// markAsJoined - Remember that CopyMI has already been joined.
+ void markAsJoined(MachineInstr *CopyMI);
+ };
+} // End llvm namespace
// Because of the way .a files work, we must force the SimpleRC
// implementation to be pulled in if the RegisterCoalescing header is
projects / oota-llvm.git / blobdiff