[PATCH] D114765: [X86][FP16] Only generate approximate rsqrt when Reciprocal is true for half type

Phoebe Wang via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Mon Nov 29 18:49:53 PST 2021


pengfei added a comment.

In D114765#3160232 <https://reviews.llvm.org/D114765#3160232>, @craig.topper wrote:

> What's the correctness issue? It's fast math so the answer isn't required to be exact.

See https://godbolt.org/z/P4Y89hsj4
I guess we need at least `RefinementSteps = 1` for correntness when `Reciprocal == 0`.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D114765/new/

https://reviews.llvm.org/D114765



More information about the llvm-commits mailing list