+/// \brief Test whether a given ConstantInt is in-range for a SequentialType.
+static bool isIndexInRangeOfSequentialType(const SequentialType *STy,
+ const ConstantInt *CI) {
+ if (const PointerType *PTy = dyn_cast<PointerType>(STy))
+ // Only handle pointers to sized types, not pointers to functions.
+ return PTy->getElementType()->isSized();
+
+ uint64_t NumElements = 0;
+ // Determine the number of elements in our sequential type.
+ if (const ArrayType *ATy = dyn_cast<ArrayType>(STy))
+ NumElements = ATy->getNumElements();
+ else if (const VectorType *VTy = dyn_cast<VectorType>(STy))
+ NumElements = VTy->getNumElements();
+
+ assert((isa<ArrayType>(STy) || NumElements > 0) &&
+ "didn't expect non-array type to have zero elements!");
+
+ // We cannot bounds check the index if it doesn't fit in an int64_t.
+ if (CI->getValue().getActiveBits() > 64)
+ return false;
+
+ // A negative index or an index past the end of our sequential type is
+ // considered out-of-range.
+ int64_t IndexVal = CI->getSExtValue();
+ if (IndexVal < 0 || (NumElements > 0 && (uint64_t)IndexVal >= NumElements))
+ return false;
+
+ // Otherwise, it is in-range.
+ return true;
+}
+