Break anti-dependence breaking out into its own class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85127 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CriticalAntiDepBreaker.h b/lib/CodeGen/CriticalAntiDepBreaker.h
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+++ b/lib/CodeGen/CriticalAntiDepBreaker.h
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+//=- llvm/CodeGen/CriticalAntiDepBreaker.h - Anti-Dep Support -*- C++ -*-=//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the CriticalAntiDepBreaker class, which
+// implements register anti-dependence breaking along a blocks
+// critical path during post-RA scheduler.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_CRITICALANTIDEPBREAKER_H
+#define LLVM_CODEGEN_CRITICALANTIDEPBREAKER_H
+
+#include "llvm/CodeGen/AntiDepBreaker.h"
+#include "llvm/CodeGen/MachineBasicBlock.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
+#include "llvm/CodeGen/MachineFunction.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/ScheduleDAG.h"
+#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/ADT/BitVector.h"
+#include "llvm/ADT/SmallSet.h"
+
+namespace llvm {
+ class CriticalAntiDepBreaker : public AntiDepBreaker {
+ MachineFunction& MF;
+ MachineRegisterInfo &MRI;
+ const TargetRegisterInfo *TRI;
+
+ /// AllocatableSet - The set of allocatable registers.
+ /// We'll be ignoring anti-dependencies on non-allocatable registers,
+ /// because they may not be safe to break.
+ const BitVector AllocatableSet;
+
+ /// Classes - For live regs that are only used in one register class in a
+ /// live range, the register class. If the register is not live, the
+ /// corresponding value is null. If the register is live but used in
+ /// multiple register classes, the corresponding value is -1 casted to a
+ /// pointer.
+ const TargetRegisterClass *
+ Classes[TargetRegisterInfo::FirstVirtualRegister];
+
+ /// RegRegs - Map registers to all their references within a live range.
+ std::multimap<unsigned, MachineOperand *> RegRefs;
+
+ /// KillIndices - The index of the most recent kill (proceding bottom-up),
+ /// or ~0u if the register is not live.
+ unsigned KillIndices[TargetRegisterInfo::FirstVirtualRegister];
+
+ /// DefIndices - The index of the most recent complete def (proceding bottom
+ /// up), or ~0u if the register is live.
+ unsigned DefIndices[TargetRegisterInfo::FirstVirtualRegister];
+
+ /// KeepRegs - A set of registers which are live and cannot be changed to
+ /// break anti-dependencies.
+ SmallSet<unsigned, 4> KeepRegs;
+
+ public:
+ CriticalAntiDepBreaker(MachineFunction& MFi);
+ ~CriticalAntiDepBreaker();
+
+ /// Start - Initialize anti-dep breaking for a new basic block.
+ void StartBlock(MachineBasicBlock *BB);
+
+ /// BreakAntiDependencies - Identifiy anti-dependencies along the critical path
+ /// of the ScheduleDAG and break them by renaming registers.
+ ///
+ unsigned BreakAntiDependencies(std::vector<SUnit>& SUnits,
+ MachineBasicBlock::iterator& Begin,
+ MachineBasicBlock::iterator& End,
+ unsigned InsertPosIndex);
+
+ /// Observe - Update liveness information to account for the current
+ /// instruction, which will not be scheduled.
+ ///
+ void Observe(MachineInstr *MI, unsigned Count, unsigned InsertPosIndex);
+
+ /// Finish - Finish anti-dep breaking for a basic block.
+ void FinishBlock();
+
+ private:
+ void PrescanInstruction(MachineInstr *MI);
+ void ScanInstruction(MachineInstr *MI, unsigned Count);
+ unsigned findSuitableFreeRegister(unsigned AntiDepReg,
+ unsigned LastNewReg,
+ const TargetRegisterClass *);
+ };
+}
+
+#endif