[PATCH] D107713: [NFC] Fix the formula for reciprocal calculation.

[LuoYuanke via Phabricator via llvm-commits]

LuoYuanke created this revision.
Herald added subscribers: ecnelises, hiraditya.
LuoYuanke requested review of this revision.
Herald added a project: LLVM.
Herald added a subscriber: llvm-commits.

Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D107713

Files:
  llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp


Index: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
===================================================================
--- llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -22877,7 +22877,7 @@
 
 /// 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:
-///   F(X) = A X - 1 [which has a zero at X = 1/A]
+///   F(X) = 1/X - A [which has a zero at X = 1/A]
 ///     =>
 ///   X_{i+1} = X_i (2 - A X_i) = X_i + X_i (1 - A X_i) [this second form
 ///     does not require additional intermediate precision]


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D107713.365015.patch
Type: text/x-patch
Size: 643 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20210808/b1aa8f47/attachment.bin>