[PATCH] D20789: Consecutive memory access in Loop Vectorizer - fixed and simplified

Adam Nemet via llvm-commits llvm-commits at lists.llvm.org
Tue Aug 2 10:40:34 PDT 2016


anemet added a comment.

In https://reviews.llvm.org/D20789#503549, @delena wrote:

> No. It says " Total Dependences: 0" because it checks only pointers with the same leader, like A[i] and A[i+5].
>  IMO, this is a bug that should be fixed. In a separate patch, of course.


You may want to reread Silviu's comment.  'Total dependences' covers dependences that can be determined *statically* by the compiler (i.e. same underlying object).  For anything else that may alias we need to add run-time alias checks to ensure no-dependence.  This latter is what should have happened in this case.


Repository:
  rL LLVM

https://reviews.llvm.org/D20789





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