Coverage Report

Created: 2019-02-15 18:59

/Users/buildslave/jenkins/workspace/clang-stage2-coverage-R/llvm/include/llvm/Analysis/PHITransAddr.h
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//===- PHITransAddr.h - PHI Translation for Addresses -----------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// This file declares the PHITransAddr class.
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_ANALYSIS_PHITRANSADDR_H
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#define LLVM_ANALYSIS_PHITRANSADDR_H
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#include "llvm/ADT/SmallVector.h"
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#include "llvm/IR/Instruction.h"
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namespace llvm {
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  class AssumptionCache;
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  class DominatorTree;
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  class DataLayout;
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  class TargetLibraryInfo;
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/// PHITransAddr - An address value which tracks and handles phi translation.
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/// As we walk "up" the CFG through predecessors, we need to ensure that the
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/// address we're tracking is kept up to date.  For example, if we're analyzing
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/// an address of "&A[i]" and walk through the definition of 'i' which is a PHI
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/// node, we *must* phi translate i to get "&A[j]" or else we will analyze an
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/// incorrect pointer in the predecessor block.
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///
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/// This is designed to be a relatively small object that lives on the stack and
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/// is copyable.
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///
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class PHITransAddr {
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  /// Addr - The actual address we're analyzing.
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  Value *Addr;
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  /// The DataLayout we are playing with.
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  const DataLayout &DL;
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  /// TLI - The target library info if known, otherwise null.
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  const TargetLibraryInfo *TLI;
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  /// A cache of \@llvm.assume calls used by SimplifyInstruction.
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  AssumptionCache *AC;
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  /// InstInputs - The inputs for our symbolic address.
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  SmallVector<Instruction*, 4> InstInputs;
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public:
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  PHITransAddr(Value *addr, const DataLayout &DL, AssumptionCache *AC)
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8.53M
      : Addr(addr), DL(DL), TLI(nullptr), AC(AC) {
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    // If the address is an instruction, the whole thing is considered an input.
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    if (Instruction *I = dyn_cast<Instruction>(Addr))
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      InstInputs.push_back(I);
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  }
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  Value *getAddr() const { return Addr; }
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  /// NeedsPHITranslationFromBlock - Return true if moving from the specified
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  /// BasicBlock to its predecessors requires PHI translation.
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  bool NeedsPHITranslationFromBlock(BasicBlock *BB) const {
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    // We do need translation if one of our input instructions is defined in
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    // this block.
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    for (unsigned i = 0, e = InstInputs.size(); i != e; 
++i5.61M
)
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      if (InstInputs[i]->getParent() == BB)
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        return true;
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11.8M
    
return false9.94M
;
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  }
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  /// IsPotentiallyPHITranslatable - If this needs PHI translation, return true
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  /// if we have some hope of doing it.  This should be used as a filter to
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  /// avoid calling PHITranslateValue in hopeless situations.
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  bool IsPotentiallyPHITranslatable() const;
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  /// PHITranslateValue - PHI translate the current address up the CFG from
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  /// CurBB to Pred, updating our state to reflect any needed changes.  If
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  /// 'MustDominate' is true, the translated value must dominate
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  /// PredBB.  This returns true on failure and sets Addr to null.
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  bool PHITranslateValue(BasicBlock *CurBB, BasicBlock *PredBB,
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                         const DominatorTree *DT, bool MustDominate);
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  /// PHITranslateWithInsertion - PHI translate this value into the specified
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  /// predecessor block, inserting a computation of the value if it is
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  /// unavailable.
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  ///
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  /// All newly created instructions are added to the NewInsts list.  This
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  /// returns null on failure.
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  ///
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  Value *PHITranslateWithInsertion(BasicBlock *CurBB, BasicBlock *PredBB,
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                                   const DominatorTree &DT,
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                                   SmallVectorImpl<Instruction *> &NewInsts);
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  void dump() const;
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  /// Verify - Check internal consistency of this data structure.  If the
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  /// structure is valid, it returns true.  If invalid, it prints errors and
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  /// returns false.
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  bool Verify() const;
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private:
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  Value *PHITranslateSubExpr(Value *V, BasicBlock *CurBB, BasicBlock *PredBB,
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                             const DominatorTree *DT);
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  /// InsertPHITranslatedSubExpr - Insert a computation of the PHI translated
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  /// version of 'V' for the edge PredBB->CurBB into the end of the PredBB
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  /// block.  All newly created instructions are added to the NewInsts list.
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  /// This returns null on failure.
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  ///
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  Value *InsertPHITranslatedSubExpr(Value *InVal, BasicBlock *CurBB,
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                                    BasicBlock *PredBB, const DominatorTree &DT,
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                                    SmallVectorImpl<Instruction *> &NewInsts);
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  /// AddAsInput - If the specified value is an instruction, add it as an input.
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  Value *AddAsInput(Value *V) {
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    // If V is an instruction, it is now an input.
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    if (Instruction *VI = dyn_cast<Instruction>(V))
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      InstInputs.push_back(VI);
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    return V;
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  }
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};
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} // end namespace llvm
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#endif