[PATCH] D45336: Apply accumulator to fadd/fmul experimental vector reductions (PR36734)

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added a comment.

In https://reviews.llvm.org/D45336#1060080, @aemerson wrote:

> The other issue is that while these intrinsics were experimental (it was on my todo list for later this year to change that), AArch64 has been using them with their original intended semantics for a while now. If we change that, IR generated from a released compiler will be miscompiled since it now becomes legal to fold away undef accumulator reductions to undef, unless we do some IR auto-upgrading based on the bitcode version.


If they are flagged as experimental surely we can't be held resposible for changes in behaviour?


Repository:
  rL LLVM

https://reviews.llvm.org/D45336