[NFC] use bitwise or instead of addition

as the bits are all distinct, these two operations have the same result,
but the bitwise operation is more explicit about what's happening.

Reviewed By: hctim

Differential Revision: https://reviews.llvm.org/D140346

Author: fmayer

llvm/lib/Transforms/Instrumentation/HWAddressSanitizer.cpp

@@ -818,11 +818,11 @@ Value *HWAddressSanitizer::memToShadow(Value *Mem, IRBuilder<> &IRB) {
 
 int64_t HWAddressSanitizer::getAccessInfo(bool IsWrite,
                                           unsigned AccessSizeIndex) {
-  return (CompileKernel << HWASanAccessInfo::CompileKernelShift) +
-         (HasMatchAllTag << HWASanAccessInfo::HasMatchAllShift) +
-         (MatchAllTag << HWASanAccessInfo::MatchAllShift) +
-         (Recover << HWASanAccessInfo::RecoverShift) +
-         (IsWrite << HWASanAccessInfo::IsWriteShift) +
+  return (CompileKernel << HWASanAccessInfo::CompileKernelShift) |
+         (HasMatchAllTag << HWASanAccessInfo::HasMatchAllShift) |
+         (MatchAllTag << HWASanAccessInfo::MatchAllShift) |
+         (Recover << HWASanAccessInfo::RecoverShift) |
+         (IsWrite << HWASanAccessInfo::IsWriteShift) |
          (AccessSizeIndex << HWASanAccessInfo::AccessSizeShift);
 }