This syntax is now preferred: def : Pat<(subc i32:$b, i32:$c), (SUBCCrr $b, $c)>; There is no reason to repeat the types in the output pattern. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@177844 91177308-0d34-0410-b5e6-96231b3b80d8