[PATCH] D38378: [ARM] Optimize {s,u}{add,sub}.with.overflow.

[Renato Golin via Phabricator via llvm-commits]

rengolin added a comment.

The change itself looks good, I only have one question to clarify a part of the code, but otherwise seems fine.

I agree with Kristof that this could span across more than just overflow, but it can be done in later patches.

The benefits are clear, even from the few tests that changed, but it would be good to have a simple test-suite run in benchmark mode, just to make sure we're not creating any new pathological case on random programs.

cheers,
--renato



================
Comment at: lib/Target/ARM/ARMBaseInstrInfo.cpp:2731
+    // Allow MI to be SubAdd.
+    --E;
   }
----------------
Can you elaborate on this change?


https://reviews.llvm.org/D38378