[AVR] Re-enable expansion of ADDE/ADDC/SUBE/SUBC in ISel

This was disabled in r333748, which broke four tests.

In the future, these need to be updated to UADDO/ADDCARRY or
USUBO/SUBCARRY.

llvm-svn: 338212
diff --git a/llvm/lib/Target/AVR/AVRISelLowering.cpp b/llvm/lib/Target/AVR/AVRISelLowering.cpp
index c151557..1b412a9 100644
--- a/llvm/lib/Target/AVR/AVRISelLowering.cpp
+++ b/llvm/lib/Target/AVR/AVRISelLowering.cpp
@@ -63,6 +63,13 @@
 
   setTruncStoreAction(MVT::i16, MVT::i8, Expand);
 
+  for (MVT VT : MVT::integer_valuetypes()) {
+    setOperationAction(ISD::ADDC, VT, Legal);
+    setOperationAction(ISD::SUBC, VT, Legal);
+    setOperationAction(ISD::ADDE, VT, Legal);
+    setOperationAction(ISD::SUBE, VT, Legal);
+  }
+
   // sub (x, imm) gets canonicalized to add (x, -imm), so for illegal types
   // revert into a sub since we don't have an add with immediate instruction.
   setOperationAction(ISD::ADD, MVT::i32, Custom);