[PATCH] D37879: [TargetTransformInfo] Instruction alloca has 0 cost

[Hal Finkel via Phabricator via llvm-commits]

hfinkel added inline comments.


================
Comment at: include/llvm/Analysis/TargetTransformInfoImpl.h:743
 
+    if (isa<AllocaInst>(U))
+      return TTI::TCC_Free;
----------------
This needs a comment. Also, I think this is only true for static allocas. Dynamic ones will still have a cost. Maybe this should be:

  if (auto *A = dyn_cast<AllocaInst>(U))
    if (A->isStaticAlloca())
      return TTI::TTC_Free;



https://reviews.llvm.org/D37879