#define LLVM_CODEGEN_SIMPLE_REGISTER_COALESCING_H
#include "llvm/CodeGen/MachineFunctionPass.h"
-#include "llvm/CodeGen/LiveInterval.h"
#include "llvm/CodeGen/LiveIntervalAnalysis.h"
#include "llvm/CodeGen/RegisterCoalescer.h"
#include "llvm/ADT/BitVector.h"
-#include "llvm/ADT/IndexedMap.h"
#include <queue>
namespace llvm {
///
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) {}
if (!li_->hasInterval(Reg))
return 0;
return li_->getApproximateInstructionCount(li_->getInterval(Reg)) *
- LiveIntervals::InstrSlots::NUM;
+ LiveInterval::InstrSlots::NUM;
}
/// print - Implement the dump method.
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. 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;
+ /// classes. The registers may be either phys or virt regs.
+ bool differingRegisterClasses(unsigned RegA, unsigned RegB) const;
/// AdjustCopiesBackFrom - We found a non-trivially-coalescable copy. If
bool RemoveCopyByCommutingDef(LiveInterval &IntA, LiveInterval &IntB,
MachineInstr *CopyMI);
- bool ReMaterializeTrivialDef(LiveInterval &SrcInt, unsigned DstReg,
- MachineInstr *CopyMI);
+ /// TrimLiveIntervalToLastUse - If there is a last use in the same basic
+ /// block as the copy instruction, trim the ive interval to the last use
+ /// and return true.
+ bool TrimLiveIntervalToLastUse(unsigned CopyIdx,
+ MachineBasicBlock *CopyMBB,
+ LiveInterval &li, const LiveRange *LR);
- /// TurnCopyIntoImpDef - If source of the specified copy is an implicit def,
- /// turn the copy into an implicit def.
- bool TurnCopyIntoImpDef(MachineBasicBlock::iterator &I,
- MachineBasicBlock *MBB,
- unsigned DstReg, unsigned SrcReg);
+ /// ReMaterializeTrivialDef - If the source of a copy is defined by a trivial
+ /// computation, replace the copy by rematerialize the definition.
+ bool ReMaterializeTrivialDef(LiveInterval &SrcInt, unsigned DstReg,
+ unsigned DstSubIdx, MachineInstr *CopyMI);
/// CanCoalesceWithImpDef - Returns true if the specified copy instruction
/// from an implicit def to another register can be coalesced away.
bool CanCoalesceWithImpDef(MachineInstr *CopyMI,
LiveInterval &li, LiveInterval &ImpLi) const;
- /// RemoveCopiesFromValNo - The specified value# is defined by an implicit
- /// def and it is being removed. Turn all copies from this value# into
- /// identity copies so they will be removed.
- void RemoveCopiesFromValNo(LiveInterval &li, VNInfo *VNI);
+ /// TurnCopiesFromValNoToImpDefs - The specified value# is defined by an
+ /// implicit_def and it is being removed. Turn all copies from this value#
+ /// into implicit_defs.
+ void TurnCopiesFromValNoToImpDefs(LiveInterval &li, VNInfo *VNI);
+
+ /// isWinToJoinVRWithSrcPhysReg - Return true if it's worth while to join a
+ /// a virtual destination register with physical source register.
+ bool isWinToJoinVRWithSrcPhysReg(MachineInstr *CopyMI,
+ MachineBasicBlock *CopyMBB,
+ LiveInterval &DstInt, LiveInterval &SrcInt);
+
+ /// isWinToJoinVRWithDstPhysReg - Return true if it's worth while to join a
+ /// copy from a virtual source register to a physical destination register.
+ bool isWinToJoinVRWithDstPhysReg(MachineInstr *CopyMI,
+ MachineBasicBlock *CopyMBB,
+ LiveInterval &DstInt, LiveInterval &SrcInt);
- /// 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);
+ /// isWinToJoinCrossClass - Return true if it's profitable to coalesce
+ /// two virtual registers from different register classes.
+ bool isWinToJoinCrossClass(unsigned LargeReg, unsigned SmallReg,
+ unsigned Threshold);
/// HasIncompatibleSubRegDefUse - If we are trying to coalesce a virtual
/// register with a physical register, check if any of the virtual register
bool HasIncompatibleSubRegDefUse(MachineInstr *CopyMI,
unsigned VirtReg, unsigned PhysReg);
+ /// CanJoinExtractSubRegToPhysReg - Return true if it's possible to coalesce
+ /// an extract_subreg where dst is a physical register, e.g.
+ /// cl = EXTRACT_SUBREG reg1024, 1
+ bool CanJoinExtractSubRegToPhysReg(unsigned DstReg, unsigned SrcReg,
+ unsigned SubIdx, unsigned &RealDstReg);
+
+ /// CanJoinInsertSubRegToPhysReg - Return true if it's possible to coalesce
+ /// an insert_subreg where src is a physical register, e.g.
+ /// reg1024 = INSERT_SUBREG reg1024, c1, 0
+ bool CanJoinInsertSubRegToPhysReg(unsigned DstReg, unsigned SrcReg,
+ unsigned SubIdx, unsigned &RealDstReg);
+
/// RangeIsDefinedByCopyFromReg - Return true if the specified live range of
/// the specified live interval is defined by a copy from the specified
/// register.
/// subregister.
void UpdateRegDefsUses(unsigned SrcReg, unsigned DstReg, unsigned SubIdx);
- /// RemoveDeadImpDef - Remove implicit_def instructions which are
- /// "re-defining" registers due to insert_subreg coalescing. e.g.
- void RemoveDeadImpDef(unsigned Reg, LiveInterval &LI);
-
/// RemoveUnnecessaryKills - Remove kill markers that are no longer accurate
/// due to live range lengthening as the result of coalescing.
void RemoveUnnecessaryKills(unsigned Reg, LiveInterval &LI);
/// live range is dead. Return true if live interval is removed.
bool ShortenDeadCopySrcLiveRange(LiveInterval &li, MachineInstr *CopyMI);
+ /// 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);
+
/// lastRegisterUse - Returns the last use of the specific register between
/// cycles Start and End or NULL if there are no uses.
MachineOperand *lastRegisterUse(unsigned Start, unsigned End, unsigned Reg,
projects / oota-llvm.git / blobdiff