[llvm] c82cb5d - [AddressSanitizer] Avoid pointer element type accesses

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2022-01-26T10:16:15+01:00
New Revision: c82cb5d0006ea486446b22cafd72f9a0923f5b5a

URL: https://github.com/llvm/llvm-project/commit/c82cb5d0006ea486446b22cafd72f9a0923f5b5a
DIFF: https://github.com/llvm/llvm-project/commit/c82cb5d0006ea486446b22cafd72f9a0923f5b5a.diff

LOG: [AddressSanitizer] Avoid pointer element type accesses

Determine masked load/store type based on the value operand and
result types, rather than pointer element type.

Added: 
    

Modified: 
    llvm/include/llvm/Transforms/Instrumentation/AddressSanitizerCommon.h
    llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp

Removed: 
    


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diff  --git a/llvm/include/llvm/Transforms/Instrumentation/AddressSanitizerCommon.h b/llvm/include/llvm/Transforms/Instrumentation/AddressSanitizerCommon.h
index 6c351e3f8e1ff..5a0fb835606a1 100644
--- a/llvm/include/llvm/Transforms/Instrumentation/AddressSanitizerCommon.h
+++ b/llvm/include/llvm/Transforms/Instrumentation/AddressSanitizerCommon.h
@@ -26,6 +26,7 @@ class InterestingMemoryOperand {
 public:
   Use *PtrUse;
   bool IsWrite;
+  Type *OpType;
   uint64_t TypeSize;
   MaybeAlign Alignment;
   // The mask Value, if we're looking at a masked load/store.
@@ -34,7 +35,8 @@ class InterestingMemoryOperand {
   InterestingMemoryOperand(Instruction *I, unsigned OperandNo, bool IsWrite,
                            class Type *OpType, MaybeAlign Alignment,
                            Value *MaybeMask = nullptr)
-      : IsWrite(IsWrite), Alignment(Alignment), MaybeMask(MaybeMask) {
+      : IsWrite(IsWrite), OpType(OpType), Alignment(Alignment),
+        MaybeMask(MaybeMask) {
     const DataLayout &DL = I->getModule()->getDataLayout();
     TypeSize = DL.getTypeStoreSizeInBits(OpType);
     PtrUse = &I->getOperandUse(OperandNo);

diff  --git a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
index 3bf2d16e7d209..6e72255e51ae0 100644
--- a/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
+++ b/llvm/lib/Transforms/Instrumentation/AddressSanitizer.cpp
@@ -1547,10 +1547,9 @@ void AddressSanitizer::getInterestingMemoryOperands(
     Interesting.emplace_back(I, XCHG->getPointerOperandIndex(), true,
                              XCHG->getCompareOperand()->getType(), None);
   } else if (auto CI = dyn_cast<CallInst>(I)) {
-    auto *F = CI->getCalledFunction();
-    if (F && (F->getName().startswith("llvm.masked.load.") ||
-              F->getName().startswith("llvm.masked.store."))) {
-      bool IsWrite = F->getName().startswith("llvm.masked.store.");
+    if (CI->getIntrinsicID() == Intrinsic::masked_load ||
+        CI->getIntrinsicID() == Intrinsic::masked_store) {
+      bool IsWrite = CI->getIntrinsicID() == Intrinsic::masked_store;
       // Masked store has an initial operand for the value.
       unsigned OpOffset = IsWrite ? 1 : 0;
       if (IsWrite ? !ClInstrumentWrites : !ClInstrumentReads)
@@ -1559,7 +1558,7 @@ void AddressSanitizer::getInterestingMemoryOperands(
       auto BasePtr = CI->getOperand(OpOffset);
       if (ignoreAccess(LI, BasePtr))
         return;
-      auto Ty = BasePtr->getType()->getPointerElementType();
+      Type *Ty = IsWrite ? CI->getArgOperand(0)->getType() : CI->getType();
       MaybeAlign Alignment = Align(1);
       // Otherwise no alignment guarantees. We probably got Undef.
       if (auto *Op = dyn_cast<ConstantInt>(CI->getOperand(1 + OpOffset)))
@@ -1653,10 +1652,10 @@ static void instrumentMaskedLoadOrStore(AddressSanitizer *Pass,
                                         const DataLayout &DL, Type *IntptrTy,
                                         Value *Mask, Instruction *I,
                                         Value *Addr, MaybeAlign Alignment,
-                                        unsigned Granularity, uint32_t TypeSize,
+                                        unsigned Granularity, Type *OpType,
                                         bool IsWrite, Value *SizeArgument,
                                         bool UseCalls, uint32_t Exp) {
-  auto *VTy = cast<FixedVectorType>(Addr->getType()->getPointerElementType());
+  auto *VTy = cast<FixedVectorType>(OpType);
   uint64_t ElemTypeSize = DL.getTypeStoreSizeInBits(VTy->getScalarType());
   unsigned Num = VTy->getNumElements();
   auto Zero = ConstantInt::get(IntptrTy, 0);
@@ -1734,7 +1733,7 @@ void AddressSanitizer::instrumentMop(ObjectSizeOffsetVisitor &ObjSizeVis,
   unsigned Granularity = 1 << Mapping.Scale;
   if (O.MaybeMask) {
     instrumentMaskedLoadOrStore(this, DL, IntptrTy, O.MaybeMask, O.getInsn(),
-                                Addr, O.Alignment, Granularity, O.TypeSize,
+                                Addr, O.Alignment, Granularity, O.OpType,
                                 O.IsWrite, nullptr, UseCalls, Exp);
   } else {
     doInstrumentAddress(this, O.getInsn(), O.getInsn(), Addr, O.Alignment,