diff options
Diffstat (limited to 'llvm/lib/CodeGen/StackProtector.cpp')
-rw-r--r-- | llvm/lib/CodeGen/StackProtector.cpp | 39 |
1 files changed, 35 insertions, 4 deletions
diff --git a/llvm/lib/CodeGen/StackProtector.cpp b/llvm/lib/CodeGen/StackProtector.cpp index 809960c..dc215a0 100644 --- a/llvm/lib/CodeGen/StackProtector.cpp +++ b/llvm/lib/CodeGen/StackProtector.cpp @@ -17,7 +17,6 @@ #include "llvm/ADT/SmallPtrSet.h" #include "llvm/ADT/Statistic.h" #include "llvm/Analysis/BranchProbabilityInfo.h" -#include "llvm/Analysis/CaptureTracking.h" #include "llvm/Analysis/EHPersonalities.h" #include "llvm/Analysis/OptimizationRemarkEmitter.h" #include "llvm/CodeGen/Passes.h" @@ -157,6 +156,40 @@ bool StackProtector::ContainsProtectableArray(Type *Ty, bool &IsLarge, return NeedsProtector; } +bool StackProtector::HasAddressTaken(const Instruction *AI) { + for (const User *U : AI->users()) { + if (const StoreInst *SI = dyn_cast<StoreInst>(U)) { + if (AI == SI->getValueOperand()) + return true; + } else if (const PtrToIntInst *SI = dyn_cast<PtrToIntInst>(U)) { + if (AI == SI->getOperand(0)) + return true; + } else if (const CallInst *CI = dyn_cast<CallInst>(U)) { + // Ignore intrinsics that are not calls. TODO: Use isLoweredToCall(). + if (!isa<DbgInfoIntrinsic>(CI) && !CI->isLifetimeStartOrEnd()) + return true; + } else if (isa<InvokeInst>(U)) { + return true; + } else if (const SelectInst *SI = dyn_cast<SelectInst>(U)) { + if (HasAddressTaken(SI)) + return true; + } else if (const PHINode *PN = dyn_cast<PHINode>(U)) { + // Keep track of what PHI nodes we have already visited to ensure + // they are only visited once. + if (VisitedPHIs.insert(PN).second) + if (HasAddressTaken(PN)) + return true; + } else if (const GetElementPtrInst *GEP = dyn_cast<GetElementPtrInst>(U)) { + if (HasAddressTaken(GEP)) + return true; + } else if (const BitCastInst *BI = dyn_cast<BitCastInst>(U)) { + if (HasAddressTaken(BI)) + return true; + } + } + return false; +} + /// Search for the first call to the llvm.stackprotector intrinsic and return it /// if present. static const CallInst *findStackProtectorIntrinsic(Function &F) { @@ -264,9 +297,7 @@ bool StackProtector::RequiresStackProtector() { continue; } - if (Strong && PointerMayBeCaptured(AI, - /* ReturnCaptures */ false, - /* StoreCaptures */ true)) { + if (Strong && HasAddressTaken(AI)) { ++NumAddrTaken; Layout.insert(std::make_pair(AI, MachineFrameInfo::SSPLK_AddrOf)); ORE.emit([&]() { |