Revert "[AMDGPU] performAddCombine should run after DAG is legalized."

This reverts commit 6b97d2995566b4dddd6bf0d75579ff44501d4494.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@331371 91177308-0d34-0410-b5e6-96231b3b80d8
2 files changed