Add note about future optimization noted in the ppc compiler writer's guide

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23245 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/PowerPC/README.txt b/lib/Target/PowerPC/README.txt
index ffc4d0b4bcee1dfd83b27cd5e0efcb4070ae4c42..c6c59560eb941c0ed84fa9fe85f04b1e3df27683 100644 (file)
--- a/lib/Target/PowerPC/README.txt
+++ b/lib/Target/PowerPC/README.txt
@@ -101,3 +101,7 @@ off of the register to avoid the lis's.  This is even more important in PIC
 mode.
 
 ===-------------------------------------------------------------------------===
+
+Implement Newton-Rhapson method for improving estimate instructions to the
+correct accuracy, and implementing divide as multiply by reciprocal when it has
+more than one use.  Itanium will want this too.