[PATCH] D22975: Compute the Newton series natively

[Tim Northover via llvm-commits]

t.p.northover added inline comments.

================
Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:14500
@@ -14499,2 +14499,3 @@
 
-SDValue DAGCombiner::BuildReciprocalEstimate(SDValue Op, SDNodeFlags *Flags) {
+/// Newton iteration for a function: F(X) is X_{i+1} = X_i - F(X_i)/F'(X_i)
+/// For the reciprocal, we need to find the zero of the function:
----------------
OK, I see that change now. But what about the block of 0-handling code moved from buildSqrtEstimate to buildSqrtEstimateImpl? I still don't see how that's an improvement.


Repository:
  rL LLVM

https://reviews.llvm.org/D22975