Imported Upstream version 5.18.0.167

Former-commit-id: 289509151e0fee68a1b591a20c9f109c3c789d3a

external/llvm/lib/CodeGen/AntiDepBreaker.h

@@ -1,88 +0,0 @@
-//===- llvm/CodeGen/AntiDepBreaker.h - Anti-Dependence Breaking -*- 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 AntiDepBreaker class, which implements
-// anti-dependence breaking heuristics for post-register-allocation scheduling.
-//
-//===----------------------------------------------------------------------===//
-
-#ifndef LLVM_LIB_CODEGEN_ANTIDEPBREAKER_H
-#define LLVM_LIB_CODEGEN_ANTIDEPBREAKER_H
-
-#include "llvm/ADT/iterator_range.h"
-#include "llvm/CodeGen/MachineBasicBlock.h"
-#include "llvm/CodeGen/MachineInstr.h"
-#include "llvm/CodeGen/MachineOperand.h"
-#include "llvm/CodeGen/ScheduleDAG.h"
-#include "llvm/Support/Compiler.h"
-#include <cassert>
-#include <utility>
-#include <vector>
-
-namespace llvm {
-
-/// This class works in conjunction with the post-RA scheduler to rename
-/// registers to break register anti-dependencies (WAR hazards).
-class LLVM_LIBRARY_VISIBILITY AntiDepBreaker {
-public:
-  using DbgValueVector =
-      std::vector<std::pair<MachineInstr *, MachineInstr *>>;
-
-  virtual ~AntiDepBreaker();
-
-  /// Initialize anti-dep breaking for a new basic block.
-  virtual void StartBlock(MachineBasicBlock *BB) = 0;
-
-  /// Identifiy anti-dependencies within a basic-block region and break them by
-  /// renaming registers. Return the number of anti-dependencies broken.
-  virtual unsigned BreakAntiDependencies(const std::vector<SUnit> &SUnits,
-                                         MachineBasicBlock::iterator Begin,
-                                         MachineBasicBlock::iterator End,
-                                         unsigned InsertPosIndex,
-                                         DbgValueVector &DbgValues) = 0;
-  
-  /// Update liveness information to account for the current
-  /// instruction, which will not be scheduled.
-  virtual void Observe(MachineInstr &MI, unsigned Count,
-                       unsigned InsertPosIndex) = 0;
-
-  /// Finish anti-dep breaking for a basic block.
-  virtual void FinishBlock() = 0;
-
-  /// Update DBG_VALUE if dependency breaker is updating
-  /// other machine instruction to use NewReg.
-  void UpdateDbgValue(MachineInstr &MI, unsigned OldReg, unsigned NewReg) {
-    assert(MI.isDebugValue() && "MI is not DBG_VALUE!");
-    if (MI.getOperand(0).isReg() && MI.getOperand(0).getReg() == OldReg)
-      MI.getOperand(0).setReg(NewReg);
-  }
-
-  /// Update all DBG_VALUE instructions that may be affected by the dependency
-  /// breaker's update of ParentMI to use NewReg.
-  void UpdateDbgValues(const DbgValueVector &DbgValues, MachineInstr *ParentMI,
-                       unsigned OldReg, unsigned NewReg) {
-    // The following code is dependent on the order in which the DbgValues are
-    // constructed in ScheduleDAGInstrs::buildSchedGraph.
-    MachineInstr *PrevDbgMI = nullptr;
-    for (const auto &DV : make_range(DbgValues.crbegin(), DbgValues.crend())) {
-      MachineInstr *PrevMI = DV.second;
-      if ((PrevMI == ParentMI) || (PrevMI == PrevDbgMI)) {
-        MachineInstr *DbgMI = DV.first;
-        UpdateDbgValue(*DbgMI, OldReg, NewReg);
-        PrevDbgMI = DbgMI;
-      } else if (PrevDbgMI) {
-        break; // If no match and already found a DBG_VALUE, we're done.
-      }
-    }
-  }
-};
-
-} // end namespace llvm
-
-#endif // LLVM_LIB_CODEGEN_ANTIDEPBREAKER_H