[InstCombine] X / (X * Y) --> 1.0 / Y

This is similar to the instsimplify fold added with D42385 
( rL323716 )
...but this can't be in instsimplify because we're creating/morphing
a different instruction.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@324927 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed