diff options
Diffstat (limited to 'llvm/lib/CodeGen/StackProtector.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/StackProtector.cpp | 21 |
1 files changed, 14 insertions, 7 deletions
diff --git a/llvm/lib/CodeGen/StackProtector.cpp b/llvm/lib/CodeGen/StackProtector.cpp index 7445f77..6765fd2 100644 --- a/llvm/lib/CodeGen/StackProtector.cpp +++ b/llvm/lib/CodeGen/StackProtector.cpp @@ -162,7 +162,7 @@ bool StackProtector::ContainsProtectableArray(Type *Ty, bool &IsLarge, } bool StackProtector::HasAddressTaken(const Instruction *AI, - uint64_t AllocSize) { + TypeSize AllocSize) { const DataLayout &DL = M->getDataLayout(); for (const User *U : AI->users()) { const auto *I = cast<Instruction>(U); @@ -170,7 +170,8 @@ bool StackProtector::HasAddressTaken(const Instruction *AI, // the bounds of the allocated object. Optional<MemoryLocation> MemLoc = MemoryLocation::getOrNone(I); if (MemLoc.hasValue() && MemLoc->Size.hasValue() && - MemLoc->Size.getValue() > AllocSize) + !TypeSize::isKnownGE(AllocSize, + TypeSize::getFixed(MemLoc->Size.getValue()))) return true; switch (I->getOpcode()) { case Instruction::Store: @@ -203,13 +204,19 @@ bool StackProtector::HasAddressTaken(const Instruction *AI, // would use it could also be out-of-bounds meaning stack protection is // required. const GetElementPtrInst *GEP = cast<GetElementPtrInst>(I); - unsigned TypeSize = DL.getIndexTypeSizeInBits(I->getType()); - APInt Offset(TypeSize, 0); - APInt MaxOffset(TypeSize, AllocSize); - if (!GEP->accumulateConstantOffset(DL, Offset) || Offset.ugt(MaxOffset)) + unsigned IndexSize = DL.getIndexTypeSizeInBits(I->getType()); + APInt Offset(IndexSize, 0); + if (!GEP->accumulateConstantOffset(DL, Offset)) + return true; + TypeSize OffsetSize = TypeSize::Fixed(Offset.getLimitedValue()); + if (!TypeSize::isKnownGT(AllocSize, OffsetSize)) return true; // Adjust AllocSize to be the space remaining after this offset. - if (HasAddressTaken(I, AllocSize - Offset.getLimitedValue())) + // We can't subtract a fixed size from a scalable one, so in that case + // assume the scalable value is of minimum size. + TypeSize NewAllocSize = + TypeSize::Fixed(AllocSize.getKnownMinValue()) - OffsetSize; + if (HasAddressTaken(I, NewAllocSize)) return true; break; } |