problem where it inline the map insertion call too aggressively. Before this
change it was producing a frame size of 24k for Select_store(), now it's down
to 10k (by calling this method rather than calling the map insertion operator).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@26094 91177308-0d34-0410-b5e6-96231b3b80d8