From: lkcl <lkcl@web>
Date: Mon, 11 Dec 2023 02:54:03 +0000 (+0000)
Subject: (no commit message)
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=69fabd43b8993f74c91a855ff0043032be9c4c66;p=libreriscv.git

---

diff --git a/openpower/sv/cr_ops.mdwn b/openpower/sv/cr_ops.mdwn
index e9d0b45a3..bcfa95e70 100644
--- a/openpower/sv/cr_ops.mdwn
+++ b/openpower/sv/cr_ops.mdwn
@@ -162,6 +162,13 @@ Also exactly as with [[sv/normal]] fail-first, VL cannot, unlike
 [[sv/ldst]], be set to an arbitrary value.  Deterministic behaviour
 is *required*.
 
+Important also to note is that reduce mode is implied by Data-Dependent Fail-First.
+In other words where normally if the destination is Scalar, the looping
+terminates at the first result, Data-Dependent Fail-First *continues*
+just as it does in reduce mode. This allows effectively *conditional*
+reduction (one register is both a source and destination) where testing of
+each result gives an option to exit.
+
 **Apparent contradictory behaviour compared to Rc=1,VLi=0**
 
 In  [[openpower/sv/normal]] mode when Rc=1 and VLi=0 the Vector of