[asan] Add const into few methods

[vitalybuka]

Summary

No functional changes

[vitalybuka]

small undo

lib/Transforms/Instrumentation/AddressSanitizer.cpp

struct AddressSanitizer : public FunctionPass {
   }
   const char *getPassName() const override {
     return "AddressSanitizerFunctionPass";
   }
   void getAnalysisUsage(AnalysisUsage &AU) const override {
     AU.addRequired<DominatorTreeWrapperPass>();
     AU.addRequired<TargetLibraryInfoWrapperPass>();
   }
-  uint64_t getAllocaSizeInBytes(AllocaInst *AI) const {
+  uint64_t getAllocaSizeInBytes(const AllocaInst &AI) const {
     uint64_t ArraySize = 1;
-    if (AI->isArrayAllocation()) {
-      ConstantInt *CI = dyn_cast<ConstantInt>(AI->getArraySize());
+    if (AI.isArrayAllocation()) {
+      const ConstantInt *CI = dyn_cast<ConstantInt>(AI.getArraySize());
       assert(CI && "non-constant array size");
       ArraySize = CI->getZExtValue();
     }
-    Type *Ty = AI->getAllocatedType();
+    Type *Ty = AI.getAllocatedType();
     uint64_t SizeInBytes =
-        AI->getModule()->getDataLayout().getTypeAllocSize(Ty);
+        AI.getModule()->getDataLayout().getTypeAllocSize(Ty);
     return SizeInBytes * ArraySize;
   }
   /// Check if we want (and can) handle this alloca.
-  bool isInterestingAlloca(AllocaInst &AI);
+  bool isInterestingAlloca(const AllocaInst &AI);
 
   /// If it is an interesting memory access, return the PointerOperand
   /// and set IsWrite/Alignment. Otherwise return nullptr.
   Value *isInterestingMemoryAccess(Instruction *I, bool *IsWrite,
                                    uint64_t *TypeSize, unsigned *Alignment);
   void instrumentMop(ObjectSizeOffsetVisitor &ObjSizeVis, Instruction *I,
                      bool UseCalls, const DataLayout &DL);
   void instrumentPointerComparisonOrSubtraction(Instruction *I);
private:
   Function *AsanErrorCallback[2][2][kNumberOfAccessSizes];
   Function *AsanMemoryAccessCallback[2][2][kNumberOfAccessSizes];
   // This array is indexed by AccessIsWrite and Experiment.
   Function *AsanErrorCallbackSized[2][2];
   Function *AsanMemoryAccessCallbackSized[2][2];
   Function *AsanMemmove, *AsanMemcpy, *AsanMemset;
   InlineAsm *EmptyAsm;
   GlobalsMetadata GlobalsMD;
-  DenseMap<AllocaInst *, bool> ProcessedAllocas;
+  DenseMap<const AllocaInst *, bool> ProcessedAllocas;
 
   friend struct FunctionStackPoisoner;
 };
 
 class AddressSanitizerModule : public ModulePass {
  public:
   explicit AddressSanitizerModule(bool CompileKernel = false,
                                   bool Recover = false)
IRB.CreateCall(
         {IRB.CreatePointerCast(MI->getOperand(0), IRB.getInt8PtrTy()),
          IRB.CreateIntCast(MI->getOperand(1), IRB.getInt32Ty(), false),
          IRB.CreateIntCast(MI->getOperand(2), IntptrTy, false)});
   }
   MI->eraseFromParent();
 }
 
 /// Check if we want (and can) handle this alloca.
-bool AddressSanitizer::isInterestingAlloca(AllocaInst &AI) {
+bool AddressSanitizer::isInterestingAlloca(const AllocaInst &AI) {
   auto PreviouslySeenAllocaInfo = ProcessedAllocas.find(&AI);
 
   if (PreviouslySeenAllocaInfo != ProcessedAllocas.end())
     return PreviouslySeenAllocaInfo->getSecond();
 
   bool IsInteresting =
       (AI.getAllocatedType()->isSized() &&
        // alloca() may be called with 0 size, ignore it.
-       ((!AI.isStaticAlloca()) || getAllocaSizeInBytes(&AI) > 0) &&
+       ((!AI.isStaticAlloca()) || getAllocaSizeInBytes(AI) > 0) &&
        // We are only interested in allocas not promotable to registers.
        // Promotable allocas are common under -O0.
        (!ClSkipPromotableAllocas || !isAllocaPromotable(&AI)) &&
        // inalloca allocas are not treated as static, and we don't want
        // dynamic alloca instrumentation for them as well.
        !AI.isUsedWithInAlloca());
 
   ProcessedAllocas[&AI] = IsInteresting;
void FunctionStackPoisoner::poisonStack() {
 
   // If we have a call to llvm.localescape, keep it in the entry block.
   if (LocalEscapeCall) LocalEscapeCall->moveBefore(InsBefore);
 
   SmallVector<ASanStackVariableDescription, 16> SVD;
   SVD.reserve(AllocaVec.size());
   for (AllocaInst *AI : AllocaVec) {
     ASanStackVariableDescription D = {AI->getName().data(),
-                                      ASan.getAllocaSizeInBytes(AI),
+                                      ASan.getAllocaSizeInBytes(*AI),
                                       AI->getAlignment(), AI, 0};
     SVD.push_back(D);
   }
   // Minimal header size (left redzone) is 4 pointers,
   // i.e. 32 bytes on 64-bit platforms and 16 bytes in 32-bit platforms.
   size_t MinHeaderSize = ASan.LongSize / 2;
   ASanStackFrameLayout L;
   ComputeASanStackFrameLayout(SVD, 1ULL << Mapping.Scale, MinHeaderSize, &L);