[ArgPromotion] Consider InvokeInst in Caller alias analysis

Check that all users of a Function are CallBase rather than CallInst
when performing alias analysis using actual arguments in the calling
function, as this check is also valid for Invoke instructions.

This allows replacing the existing check with an assert, as the Function
only being used by CallBase derived instructions is a precondition of
the transform.

This addresses post-commit review on llvm#106216.

Author: hazzlim

llvm/lib/Transforms/IPO/ArgumentPromotion.cpp

@@ -491,10 +491,8 @@ static bool isArgUnmodifiedByAllCalls(Argument *Arg,
                                       FunctionAnalysisManager &FAM) {
   for (User *U : Arg->getParent()->users()) {
 
-    // Bail if we find an unexpected (non CallInst) use of the function.
-    auto *Call = dyn_cast<CallInst>(U);
-    if (!Call)
-      return false;
+    assert(isa<CallBase>(U) && "Expected all users of Function to be CallBase");
+    CallBase *Call = cast<CallBase>(U);
 
     MemoryLocation Loc =
         MemoryLocation::getForArgument(Call, Arg->getArgNo(), nullptr);