[PATCH] D35035: [InstCombine] Prevent memcpy generation for small data size

[Sanjay Patel via Phabricator via llvm-commits]

spatel added inline comments.


================
Comment at: lib/Transforms/InstCombine/InstCombineCalls.cpp:185-186
 
   // If MemCpyInst length is 1/2/4/8 bytes then replace memcpy with
   // load/store.
   ConstantInt *MemOpLength = dyn_cast<ConstantInt>(MI->getArgOperand(2));
----------------
This comment is wrong now? I'm still confused about the current behavior and what this patch is changing. 

Did you see my earlier comment to check in minimal tests to trunk before this patch so we have a baseline view of the current behavior? Do the tests really need loops, attributes, globals, etc?

If there are no legal types in the DL, why wouldn't we just bail out rather than assuming that 32-bit and smaller is safe/desirable to transform?


https://reviews.llvm.org/D35035