forked from OSchip/llvm-project
				
			
		
			
				
	
	
		
			697 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			697 lines
		
	
	
		
			23 KiB
		
	
	
	
		
			C++
		
	
	
	
//===- StackSafetyAnalysis.cpp - Stack memory safety analysis -------------===//
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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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//===----------------------------------------------------------------------===//
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#include "llvm/Analysis/StackSafetyAnalysis.h"
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#include "llvm/Analysis/ScalarEvolutionExpressions.h"
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#include "llvm/IR/CallSite.h"
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#include "llvm/IR/InstIterator.h"
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#include "llvm/IR/IntrinsicInst.h"
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#include "llvm/InitializePasses.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/raw_ostream.h"
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using namespace llvm;
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#define DEBUG_TYPE "stack-safety"
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static cl::opt<int> StackSafetyMaxIterations("stack-safety-max-iterations",
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                                             cl::init(20), cl::Hidden);
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namespace {
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/// Rewrite an SCEV expression for a memory access address to an expression that
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/// represents offset from the given alloca.
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class AllocaOffsetRewriter : public SCEVRewriteVisitor<AllocaOffsetRewriter> {
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  const Value *AllocaPtr;
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public:
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  AllocaOffsetRewriter(ScalarEvolution &SE, const Value *AllocaPtr)
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      : SCEVRewriteVisitor(SE), AllocaPtr(AllocaPtr) {}
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  const SCEV *visit(const SCEV *Expr) {
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    // Only re-write the expression if the alloca is used in an addition
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    // expression (it can be used in other types of expressions if it's cast to
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    // an int and passed as an argument.)
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    if (!isa<SCEVAddRecExpr>(Expr) && !isa<SCEVAddExpr>(Expr) &&
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        !isa<SCEVUnknown>(Expr))
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      return Expr;
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    return SCEVRewriteVisitor<AllocaOffsetRewriter>::visit(Expr);
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  }
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  const SCEV *visitUnknown(const SCEVUnknown *Expr) {
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    // FIXME: look through one or several levels of definitions?
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    // This can be inttoptr(AllocaPtr) and SCEV would not unwrap
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    // it for us.
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    if (Expr->getValue() == AllocaPtr)
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      return SE.getZero(Expr->getType());
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    return Expr;
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  }
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};
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/// Describes use of address in as a function call argument.
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struct PassAsArgInfo {
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  /// Function being called.
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  const GlobalValue *Callee = nullptr;
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  /// Index of argument which pass address.
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  size_t ParamNo = 0;
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  // Offset range of address from base address (alloca or calling function
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  // argument).
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  // Range should never set to empty-set, that is an invalid access range
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  // that can cause empty-set to be propagated with ConstantRange::add
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  ConstantRange Offset;
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  PassAsArgInfo(const GlobalValue *Callee, size_t ParamNo, ConstantRange Offset)
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      : Callee(Callee), ParamNo(ParamNo), Offset(Offset) {}
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  StringRef getName() const { return Callee->getName(); }
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};
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raw_ostream &operator<<(raw_ostream &OS, const PassAsArgInfo &P) {
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  return OS << "@" << P.getName() << "(arg" << P.ParamNo << ", " << P.Offset
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            << ")";
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}
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/// Describe uses of address (alloca or parameter) inside of the function.
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struct UseInfo {
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  // Access range if the address (alloca or parameters).
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  // It is allowed to be empty-set when there are no known accesses.
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  ConstantRange Range;
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  // List of calls which pass address as an argument.
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  SmallVector<PassAsArgInfo, 4> Calls;
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  explicit UseInfo(unsigned PointerSize) : Range{PointerSize, false} {}
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  void updateRange(ConstantRange R) { Range = Range.unionWith(R); }
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};
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raw_ostream &operator<<(raw_ostream &OS, const UseInfo &U) {
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  OS << U.Range;
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  for (auto &Call : U.Calls)
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    OS << ", " << Call;
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  return OS;
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}
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struct AllocaInfo {
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  const AllocaInst *AI = nullptr;
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  uint64_t Size = 0;
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  UseInfo Use;
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  AllocaInfo(unsigned PointerSize, const AllocaInst *AI, uint64_t Size)
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      : AI(AI), Size(Size), Use(PointerSize) {}
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  StringRef getName() const { return AI->getName(); }
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};
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raw_ostream &operator<<(raw_ostream &OS, const AllocaInfo &A) {
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  return OS << A.getName() << "[" << A.Size << "]: " << A.Use;
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}
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struct ParamInfo {
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  const Argument *Arg = nullptr;
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  UseInfo Use;
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  explicit ParamInfo(unsigned PointerSize, const Argument *Arg)
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      : Arg(Arg), Use(PointerSize) {}
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  StringRef getName() const { return Arg ? Arg->getName() : "<N/A>"; }
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};
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raw_ostream &operator<<(raw_ostream &OS, const ParamInfo &P) {
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  return OS << P.getName() << "[]: " << P.Use;
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}
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/// Calculate the allocation size of a given alloca. Returns 0 if the
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/// size can not be statically determined.
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uint64_t getStaticAllocaAllocationSize(const AllocaInst *AI) {
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  const DataLayout &DL = AI->getModule()->getDataLayout();
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  TypeSize TS = DL.getTypeAllocSize(AI->getAllocatedType());
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  if (TS.isScalable())
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    return 0;
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  uint64_t Size = TS.getFixedSize();
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  if (AI->isArrayAllocation()) {
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    auto C = dyn_cast<ConstantInt>(AI->getArraySize());
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    if (!C)
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      return 0;
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    Size *= C->getZExtValue();
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  }
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  return Size;
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}
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} // end anonymous namespace
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/// Describes uses of allocas and parameters inside of a single function.
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struct StackSafetyInfo::FunctionInfo {
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  // May be a Function or a GlobalAlias
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  const GlobalValue *GV = nullptr;
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  // Informations about allocas uses.
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  SmallVector<AllocaInfo, 4> Allocas;
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  // Informations about parameters uses.
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  SmallVector<ParamInfo, 4> Params;
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  // TODO: describe return value as depending on one or more of its arguments.
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  // StackSafetyDataFlowAnalysis counter stored here for faster access.
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  int UpdateCount = 0;
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  FunctionInfo(const StackSafetyInfo &SSI) : FunctionInfo(*SSI.Info) {}
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  explicit FunctionInfo(const Function *F) : GV(F){};
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  // Creates FunctionInfo that forwards all the parameters to the aliasee.
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  explicit FunctionInfo(const GlobalAlias *A);
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  FunctionInfo(FunctionInfo &&) = default;
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  bool IsDSOLocal() const { return GV->isDSOLocal(); };
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  bool IsInterposable() const { return GV->isInterposable(); };
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  StringRef getName() const { return GV->getName(); }
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  void print(raw_ostream &O) const {
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    // TODO: Consider different printout format after
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    // StackSafetyDataFlowAnalysis. Calls and parameters are irrelevant then.
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    O << "  @" << getName() << (IsDSOLocal() ? "" : " dso_preemptable")
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      << (IsInterposable() ? " interposable" : "") << "\n";
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    O << "    args uses:\n";
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    for (auto &P : Params)
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      O << "      " << P << "\n";
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    O << "    allocas uses:\n";
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    for (auto &AS : Allocas)
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      O << "      " << AS << "\n";
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  }
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private:
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  FunctionInfo(const FunctionInfo &) = default;
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};
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StackSafetyInfo::FunctionInfo::FunctionInfo(const GlobalAlias *A) : GV(A) {
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  unsigned PointerSize = A->getParent()->getDataLayout().getPointerSizeInBits();
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  const GlobalObject *Aliasee = A->getBaseObject();
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  const FunctionType *Type = cast<FunctionType>(Aliasee->getValueType());
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  // 'Forward' all parameters to this alias to the aliasee
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  for (unsigned ArgNo = 0; ArgNo < Type->getNumParams(); ArgNo++) {
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    Params.emplace_back(PointerSize, nullptr);
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    UseInfo &US = Params.back().Use;
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    US.Calls.emplace_back(Aliasee, ArgNo, ConstantRange(APInt(PointerSize, 0)));
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  }
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}
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namespace {
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class StackSafetyLocalAnalysis {
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  const Function &F;
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  const DataLayout &DL;
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  ScalarEvolution &SE;
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  unsigned PointerSize = 0;
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  const ConstantRange UnknownRange;
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  ConstantRange offsetFromAlloca(Value *Addr, const Value *AllocaPtr);
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  ConstantRange getAccessRange(Value *Addr, const Value *AllocaPtr,
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                               ConstantRange SizeRange);
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  ConstantRange getAccessRange(Value *Addr, const Value *AllocaPtr,
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                               TypeSize Size);
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  ConstantRange getMemIntrinsicAccessRange(const MemIntrinsic *MI, const Use &U,
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                                           const Value *AllocaPtr);
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  bool analyzeAllUses(const Value *Ptr, UseInfo &AS);
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  ConstantRange getRange(uint64_t Lower, uint64_t Upper) const {
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    return ConstantRange(APInt(PointerSize, Lower), APInt(PointerSize, Upper));
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  }
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public:
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  StackSafetyLocalAnalysis(const Function &F, ScalarEvolution &SE)
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      : F(F), DL(F.getParent()->getDataLayout()), SE(SE),
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        PointerSize(DL.getPointerSizeInBits()),
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        UnknownRange(PointerSize, true) {}
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  // Run the transformation on the associated function.
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  StackSafetyInfo run();
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};
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ConstantRange
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StackSafetyLocalAnalysis::offsetFromAlloca(Value *Addr,
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                                           const Value *AllocaPtr) {
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  if (!SE.isSCEVable(Addr->getType()))
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    return UnknownRange;
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  AllocaOffsetRewriter Rewriter(SE, AllocaPtr);
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  const SCEV *Expr = Rewriter.visit(SE.getSCEV(Addr));
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  ConstantRange Offset = SE.getUnsignedRange(Expr).zextOrTrunc(PointerSize);
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  assert(!Offset.isEmptySet());
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  return Offset;
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}
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ConstantRange
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StackSafetyLocalAnalysis::getAccessRange(Value *Addr, const Value *AllocaPtr,
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                                         ConstantRange SizeRange) {
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  // Zero-size loads and stores do not access memory.
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  if (SizeRange.isEmptySet())
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    return ConstantRange::getEmpty(PointerSize);
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  if (!SE.isSCEVable(Addr->getType()))
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    return UnknownRange;
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  AllocaOffsetRewriter Rewriter(SE, AllocaPtr);
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  const SCEV *Expr = Rewriter.visit(SE.getSCEV(Addr));
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  ConstantRange AccessStartRange =
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      SE.getUnsignedRange(Expr).zextOrTrunc(PointerSize);
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  ConstantRange AccessRange = AccessStartRange.add(SizeRange);
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  assert(!AccessRange.isEmptySet());
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  return AccessRange;
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}
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ConstantRange StackSafetyLocalAnalysis::getAccessRange(Value *Addr,
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                                                       const Value *AllocaPtr,
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                                                       TypeSize Size) {
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  ConstantRange SizeRange = Size.isScalable()
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                                ? ConstantRange::getFull(PointerSize)
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                                : getRange(0, Size.getFixedSize());
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  return getAccessRange(Addr, AllocaPtr, SizeRange);
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}
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ConstantRange StackSafetyLocalAnalysis::getMemIntrinsicAccessRange(
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    const MemIntrinsic *MI, const Use &U, const Value *AllocaPtr) {
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  if (auto MTI = dyn_cast<MemTransferInst>(MI)) {
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    if (MTI->getRawSource() != U && MTI->getRawDest() != U)
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      return getRange(0, 1);
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  } else {
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    if (MI->getRawDest() != U)
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      return getRange(0, 1);
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  }
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  const auto *Len = dyn_cast<ConstantInt>(MI->getLength());
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  // Non-constant size => unsafe. FIXME: try SCEV getRange.
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  if (!Len)
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    return UnknownRange;
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  ConstantRange AccessRange =
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      getAccessRange(U, AllocaPtr, getRange(0, Len->getZExtValue()));
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  return AccessRange;
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}
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/// The function analyzes all local uses of Ptr (alloca or argument) and
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/// calculates local access range and all function calls where it was used.
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bool StackSafetyLocalAnalysis::analyzeAllUses(const Value *Ptr, UseInfo &US) {
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  SmallPtrSet<const Value *, 16> Visited;
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  SmallVector<const Value *, 8> WorkList;
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  WorkList.push_back(Ptr);
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  // A DFS search through all uses of the alloca in bitcasts/PHI/GEPs/etc.
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  while (!WorkList.empty()) {
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    const Value *V = WorkList.pop_back_val();
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    for (const Use &UI : V->uses()) {
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      auto I = cast<const Instruction>(UI.getUser());
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      assert(V == UI.get());
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      switch (I->getOpcode()) {
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      case Instruction::Load: {
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        US.updateRange(
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            getAccessRange(UI, Ptr, DL.getTypeStoreSize(I->getType())));
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        break;
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      }
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      case Instruction::VAArg:
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        // "va-arg" from a pointer is safe.
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        break;
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      case Instruction::Store: {
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        if (V == I->getOperand(0)) {
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          // Stored the pointer - conservatively assume it may be unsafe.
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          US.updateRange(UnknownRange);
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          return false;
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        }
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        US.updateRange(getAccessRange(
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            UI, Ptr, DL.getTypeStoreSize(I->getOperand(0)->getType())));
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        break;
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      }
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      case Instruction::Ret:
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        // Information leak.
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        // FIXME: Process parameters correctly. This is a leak only if we return
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        // alloca.
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        US.updateRange(UnknownRange);
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        return false;
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      case Instruction::Call:
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      case Instruction::Invoke: {
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        ImmutableCallSite CS(I);
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        if (I->isLifetimeStartOrEnd())
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          break;
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        if (const MemIntrinsic *MI = dyn_cast<MemIntrinsic>(I)) {
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          US.updateRange(getMemIntrinsicAccessRange(MI, UI, Ptr));
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          break;
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        }
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        // FIXME: consult devirt?
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        // Do not follow aliases, otherwise we could inadvertently follow
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        // dso_preemptable aliases or aliases with interposable linkage.
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        const GlobalValue *Callee =
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            dyn_cast<GlobalValue>(CS.getCalledValue()->stripPointerCasts());
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        if (!Callee) {
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          US.updateRange(UnknownRange);
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          return false;
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        }
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        assert(isa<Function>(Callee) || isa<GlobalAlias>(Callee));
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        ImmutableCallSite::arg_iterator B = CS.arg_begin(), E = CS.arg_end();
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        for (ImmutableCallSite::arg_iterator A = B; A != E; ++A) {
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          if (A->get() == V) {
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            ConstantRange Offset = offsetFromAlloca(UI, Ptr);
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            US.Calls.emplace_back(Callee, A - B, Offset);
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          }
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        }
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        break;
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      }
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      default:
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        if (Visited.insert(I).second)
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          WorkList.push_back(cast<const Instruction>(I));
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      }
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    }
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  }
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  return true;
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}
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StackSafetyInfo StackSafetyLocalAnalysis::run() {
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  StackSafetyInfo::FunctionInfo Info(&F);
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  assert(!F.isDeclaration() &&
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         "Can't run StackSafety on a function declaration");
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  LLVM_DEBUG(dbgs() << "[StackSafety] " << F.getName() << "\n");
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  for (auto &I : instructions(F)) {
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    if (auto AI = dyn_cast<AllocaInst>(&I)) {
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      Info.Allocas.emplace_back(PointerSize, AI,
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                                getStaticAllocaAllocationSize(AI));
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      AllocaInfo &AS = Info.Allocas.back();
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      analyzeAllUses(AI, AS.Use);
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    }
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  }
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  for (const Argument &A : make_range(F.arg_begin(), F.arg_end())) {
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    Info.Params.emplace_back(PointerSize, &A);
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    ParamInfo &PS = Info.Params.back();
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    analyzeAllUses(&A, PS.Use);
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  }
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  LLVM_DEBUG(dbgs() << "[StackSafety] done\n");
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  LLVM_DEBUG(Info.print(dbgs()));
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  return StackSafetyInfo(std::move(Info));
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}
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class StackSafetyDataFlowAnalysis {
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  using FunctionMap =
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      std::map<const GlobalValue *, StackSafetyInfo::FunctionInfo>;
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  FunctionMap Functions;
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  // Callee-to-Caller multimap.
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  DenseMap<const GlobalValue *, SmallVector<const GlobalValue *, 4>> Callers;
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  SetVector<const GlobalValue *> WorkList;
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  unsigned PointerSize = 0;
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  const ConstantRange UnknownRange;
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  ConstantRange getArgumentAccessRange(const GlobalValue *Callee,
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                                       unsigned ParamNo) const;
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  bool updateOneUse(UseInfo &US, bool UpdateToFullSet);
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  void updateOneNode(const GlobalValue *Callee,
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                     StackSafetyInfo::FunctionInfo &FS);
 | 
						|
  void updateOneNode(const GlobalValue *Callee) {
 | 
						|
    updateOneNode(Callee, Functions.find(Callee)->second);
 | 
						|
  }
 | 
						|
  void updateAllNodes() {
 | 
						|
    for (auto &F : Functions)
 | 
						|
      updateOneNode(F.first, F.second);
 | 
						|
  }
 | 
						|
  void runDataFlow();
 | 
						|
#ifndef NDEBUG
 | 
						|
  void verifyFixedPoint();
 | 
						|
#endif
 | 
						|
 | 
						|
public:
 | 
						|
  StackSafetyDataFlowAnalysis(
 | 
						|
      Module &M, std::function<const StackSafetyInfo &(Function &)> FI);
 | 
						|
  StackSafetyGlobalInfo run();
 | 
						|
};
 | 
						|
 | 
						|
StackSafetyDataFlowAnalysis::StackSafetyDataFlowAnalysis(
 | 
						|
    Module &M, std::function<const StackSafetyInfo &(Function &)> FI)
 | 
						|
    : PointerSize(M.getDataLayout().getPointerSizeInBits()),
 | 
						|
      UnknownRange(PointerSize, true) {
 | 
						|
  // Without ThinLTO, run the local analysis for every function in the TU and
 | 
						|
  // then run the DFA.
 | 
						|
  for (auto &F : M.functions())
 | 
						|
    if (!F.isDeclaration())
 | 
						|
      Functions.emplace(&F, FI(F));
 | 
						|
  for (auto &A : M.aliases())
 | 
						|
    if (isa<Function>(A.getBaseObject()))
 | 
						|
      Functions.emplace(&A, StackSafetyInfo::FunctionInfo(&A));
 | 
						|
}
 | 
						|
 | 
						|
ConstantRange
 | 
						|
StackSafetyDataFlowAnalysis::getArgumentAccessRange(const GlobalValue *Callee,
 | 
						|
                                                    unsigned ParamNo) const {
 | 
						|
  auto IT = Functions.find(Callee);
 | 
						|
  // Unknown callee (outside of LTO domain or an indirect call).
 | 
						|
  if (IT == Functions.end())
 | 
						|
    return UnknownRange;
 | 
						|
  const StackSafetyInfo::FunctionInfo &FS = IT->second;
 | 
						|
  // The definition of this symbol may not be the definition in this linkage
 | 
						|
  // unit.
 | 
						|
  if (!FS.IsDSOLocal() || FS.IsInterposable())
 | 
						|
    return UnknownRange;
 | 
						|
  if (ParamNo >= FS.Params.size()) // possibly vararg
 | 
						|
    return UnknownRange;
 | 
						|
  return FS.Params[ParamNo].Use.Range;
 | 
						|
}
 | 
						|
 | 
						|
bool StackSafetyDataFlowAnalysis::updateOneUse(UseInfo &US,
 | 
						|
                                               bool UpdateToFullSet) {
 | 
						|
  bool Changed = false;
 | 
						|
  for (auto &CS : US.Calls) {
 | 
						|
    assert(!CS.Offset.isEmptySet() &&
 | 
						|
           "Param range can't be empty-set, invalid offset range");
 | 
						|
 | 
						|
    ConstantRange CalleeRange = getArgumentAccessRange(CS.Callee, CS.ParamNo);
 | 
						|
    CalleeRange = CalleeRange.add(CS.Offset);
 | 
						|
    if (!US.Range.contains(CalleeRange)) {
 | 
						|
      Changed = true;
 | 
						|
      if (UpdateToFullSet)
 | 
						|
        US.Range = UnknownRange;
 | 
						|
      else
 | 
						|
        US.Range = US.Range.unionWith(CalleeRange);
 | 
						|
    }
 | 
						|
  }
 | 
						|
  return Changed;
 | 
						|
}
 | 
						|
 | 
						|
void StackSafetyDataFlowAnalysis::updateOneNode(
 | 
						|
    const GlobalValue *Callee, StackSafetyInfo::FunctionInfo &FS) {
 | 
						|
  bool UpdateToFullSet = FS.UpdateCount > StackSafetyMaxIterations;
 | 
						|
  bool Changed = false;
 | 
						|
  for (auto &AS : FS.Allocas)
 | 
						|
    Changed |= updateOneUse(AS.Use, UpdateToFullSet);
 | 
						|
  for (auto &PS : FS.Params)
 | 
						|
    Changed |= updateOneUse(PS.Use, UpdateToFullSet);
 | 
						|
 | 
						|
  if (Changed) {
 | 
						|
    LLVM_DEBUG(dbgs() << "=== update [" << FS.UpdateCount
 | 
						|
                      << (UpdateToFullSet ? ", full-set" : "") << "] "
 | 
						|
                      << FS.getName() << "\n");
 | 
						|
    // Callers of this function may need updating.
 | 
						|
    for (auto &CallerID : Callers[Callee])
 | 
						|
      WorkList.insert(CallerID);
 | 
						|
 | 
						|
    ++FS.UpdateCount;
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
void StackSafetyDataFlowAnalysis::runDataFlow() {
 | 
						|
  Callers.clear();
 | 
						|
  WorkList.clear();
 | 
						|
 | 
						|
  SmallVector<const GlobalValue *, 16> Callees;
 | 
						|
  for (auto &F : Functions) {
 | 
						|
    Callees.clear();
 | 
						|
    StackSafetyInfo::FunctionInfo &FS = F.second;
 | 
						|
    for (auto &AS : FS.Allocas)
 | 
						|
      for (auto &CS : AS.Use.Calls)
 | 
						|
        Callees.push_back(CS.Callee);
 | 
						|
    for (auto &PS : FS.Params)
 | 
						|
      for (auto &CS : PS.Use.Calls)
 | 
						|
        Callees.push_back(CS.Callee);
 | 
						|
 | 
						|
    llvm::sort(Callees);
 | 
						|
    Callees.erase(std::unique(Callees.begin(), Callees.end()), Callees.end());
 | 
						|
 | 
						|
    for (auto &Callee : Callees)
 | 
						|
      Callers[Callee].push_back(F.first);
 | 
						|
  }
 | 
						|
 | 
						|
  updateAllNodes();
 | 
						|
 | 
						|
  while (!WorkList.empty()) {
 | 
						|
    const GlobalValue *Callee = WorkList.back();
 | 
						|
    WorkList.pop_back();
 | 
						|
    updateOneNode(Callee);
 | 
						|
  }
 | 
						|
}
 | 
						|
 | 
						|
#ifndef NDEBUG
 | 
						|
void StackSafetyDataFlowAnalysis::verifyFixedPoint() {
 | 
						|
  WorkList.clear();
 | 
						|
  updateAllNodes();
 | 
						|
  assert(WorkList.empty());
 | 
						|
}
 | 
						|
#endif
 | 
						|
 | 
						|
StackSafetyGlobalInfo StackSafetyDataFlowAnalysis::run() {
 | 
						|
  runDataFlow();
 | 
						|
  LLVM_DEBUG(verifyFixedPoint());
 | 
						|
 | 
						|
  StackSafetyGlobalInfo SSI;
 | 
						|
  for (auto &F : Functions)
 | 
						|
    SSI.emplace(F.first, std::move(F.second));
 | 
						|
  return SSI;
 | 
						|
}
 | 
						|
 | 
						|
void print(const StackSafetyGlobalInfo &SSI, raw_ostream &O, const Module &M) {
 | 
						|
  size_t Count = 0;
 | 
						|
  for (auto &F : M.functions())
 | 
						|
    if (!F.isDeclaration()) {
 | 
						|
      SSI.find(&F)->second.print(O);
 | 
						|
      O << "\n";
 | 
						|
      ++Count;
 | 
						|
    }
 | 
						|
  for (auto &A : M.aliases()) {
 | 
						|
    SSI.find(&A)->second.print(O);
 | 
						|
    O << "\n";
 | 
						|
    ++Count;
 | 
						|
  }
 | 
						|
  assert(Count == SSI.size() && "Unexpected functions in the result");
 | 
						|
}
 | 
						|
 | 
						|
} // end anonymous namespace
 | 
						|
 | 
						|
StackSafetyInfo::StackSafetyInfo() = default;
 | 
						|
StackSafetyInfo::StackSafetyInfo(StackSafetyInfo &&) = default;
 | 
						|
StackSafetyInfo &StackSafetyInfo::operator=(StackSafetyInfo &&) = default;
 | 
						|
 | 
						|
StackSafetyInfo::StackSafetyInfo(FunctionInfo &&Info)
 | 
						|
    : Info(new FunctionInfo(std::move(Info))) {}
 | 
						|
 | 
						|
StackSafetyInfo::~StackSafetyInfo() = default;
 | 
						|
 | 
						|
void StackSafetyInfo::print(raw_ostream &O) const { Info->print(O); }
 | 
						|
 | 
						|
AnalysisKey StackSafetyAnalysis::Key;
 | 
						|
 | 
						|
StackSafetyInfo StackSafetyAnalysis::run(Function &F,
 | 
						|
                                         FunctionAnalysisManager &AM) {
 | 
						|
  StackSafetyLocalAnalysis SSLA(F, AM.getResult<ScalarEvolutionAnalysis>(F));
 | 
						|
  return SSLA.run();
 | 
						|
}
 | 
						|
 | 
						|
PreservedAnalyses StackSafetyPrinterPass::run(Function &F,
 | 
						|
                                              FunctionAnalysisManager &AM) {
 | 
						|
  OS << "'Stack Safety Local Analysis' for function '" << F.getName() << "'\n";
 | 
						|
  AM.getResult<StackSafetyAnalysis>(F).print(OS);
 | 
						|
  return PreservedAnalyses::all();
 | 
						|
}
 | 
						|
 | 
						|
char StackSafetyInfoWrapperPass::ID = 0;
 | 
						|
 | 
						|
StackSafetyInfoWrapperPass::StackSafetyInfoWrapperPass() : FunctionPass(ID) {
 | 
						|
  initializeStackSafetyInfoWrapperPassPass(*PassRegistry::getPassRegistry());
 | 
						|
}
 | 
						|
 | 
						|
void StackSafetyInfoWrapperPass::getAnalysisUsage(AnalysisUsage &AU) const {
 | 
						|
  AU.addRequired<ScalarEvolutionWrapperPass>();
 | 
						|
  AU.setPreservesAll();
 | 
						|
}
 | 
						|
 | 
						|
void StackSafetyInfoWrapperPass::print(raw_ostream &O, const Module *M) const {
 | 
						|
  SSI.print(O);
 | 
						|
}
 | 
						|
 | 
						|
bool StackSafetyInfoWrapperPass::runOnFunction(Function &F) {
 | 
						|
  StackSafetyLocalAnalysis SSLA(
 | 
						|
      F, getAnalysis<ScalarEvolutionWrapperPass>().getSE());
 | 
						|
  SSI = StackSafetyInfo(SSLA.run());
 | 
						|
  return false;
 | 
						|
}
 | 
						|
 | 
						|
AnalysisKey StackSafetyGlobalAnalysis::Key;
 | 
						|
 | 
						|
StackSafetyGlobalInfo
 | 
						|
StackSafetyGlobalAnalysis::run(Module &M, ModuleAnalysisManager &AM) {
 | 
						|
  FunctionAnalysisManager &FAM =
 | 
						|
      AM.getResult<FunctionAnalysisManagerModuleProxy>(M).getManager();
 | 
						|
 | 
						|
  StackSafetyDataFlowAnalysis SSDFA(
 | 
						|
      M, [&FAM](Function &F) -> const StackSafetyInfo & {
 | 
						|
        return FAM.getResult<StackSafetyAnalysis>(F);
 | 
						|
      });
 | 
						|
  return SSDFA.run();
 | 
						|
}
 | 
						|
 | 
						|
PreservedAnalyses StackSafetyGlobalPrinterPass::run(Module &M,
 | 
						|
                                                    ModuleAnalysisManager &AM) {
 | 
						|
  OS << "'Stack Safety Analysis' for module '" << M.getName() << "'\n";
 | 
						|
  print(AM.getResult<StackSafetyGlobalAnalysis>(M), OS, M);
 | 
						|
  return PreservedAnalyses::all();
 | 
						|
}
 | 
						|
 | 
						|
char StackSafetyGlobalInfoWrapperPass::ID = 0;
 | 
						|
 | 
						|
StackSafetyGlobalInfoWrapperPass::StackSafetyGlobalInfoWrapperPass()
 | 
						|
    : ModulePass(ID) {
 | 
						|
  initializeStackSafetyGlobalInfoWrapperPassPass(
 | 
						|
      *PassRegistry::getPassRegistry());
 | 
						|
}
 | 
						|
 | 
						|
void StackSafetyGlobalInfoWrapperPass::print(raw_ostream &O,
 | 
						|
                                             const Module *M) const {
 | 
						|
  ::print(SSI, O, *M);
 | 
						|
}
 | 
						|
 | 
						|
void StackSafetyGlobalInfoWrapperPass::getAnalysisUsage(
 | 
						|
    AnalysisUsage &AU) const {
 | 
						|
  AU.addRequired<StackSafetyInfoWrapperPass>();
 | 
						|
}
 | 
						|
 | 
						|
bool StackSafetyGlobalInfoWrapperPass::runOnModule(Module &M) {
 | 
						|
  StackSafetyDataFlowAnalysis SSDFA(
 | 
						|
      M, [this](Function &F) -> const StackSafetyInfo & {
 | 
						|
        return getAnalysis<StackSafetyInfoWrapperPass>(F).getResult();
 | 
						|
      });
 | 
						|
  SSI = SSDFA.run();
 | 
						|
  return false;
 | 
						|
}
 | 
						|
 | 
						|
static const char LocalPassArg[] = "stack-safety-local";
 | 
						|
static const char LocalPassName[] = "Stack Safety Local Analysis";
 | 
						|
INITIALIZE_PASS_BEGIN(StackSafetyInfoWrapperPass, LocalPassArg, LocalPassName,
 | 
						|
                      false, true)
 | 
						|
INITIALIZE_PASS_DEPENDENCY(ScalarEvolutionWrapperPass)
 | 
						|
INITIALIZE_PASS_END(StackSafetyInfoWrapperPass, LocalPassArg, LocalPassName,
 | 
						|
                    false, true)
 | 
						|
 | 
						|
static const char GlobalPassName[] = "Stack Safety Analysis";
 | 
						|
INITIALIZE_PASS_BEGIN(StackSafetyGlobalInfoWrapperPass, DEBUG_TYPE,
 | 
						|
                      GlobalPassName, false, false)
 | 
						|
INITIALIZE_PASS_DEPENDENCY(StackSafetyInfoWrapperPass)
 | 
						|
INITIALIZE_PASS_END(StackSafetyGlobalInfoWrapperPass, DEBUG_TYPE,
 | 
						|
                    GlobalPassName, false, false)
 |