the variable actually tracks.
N.B., several back-ends are using "HasCalls" as being synonymous for something
that adjusts the stack. This isn't 100% correct and should be looked into.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103802 91177308-0d34-0410-b5e6-96231b3b80d8