Modified LinearFunctionTestReplace to push the condition on the dead
list instead of eagerly deleting it. This can cause unnecessary
IV rewrites, which should have no effect on codegen and will not be an
issue once we stop generating canonical IVs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@130340 91177308-0d34-0410-b5e6-96231b3b80d8
