From: lkcl <lkcl@web>
Date: Sun, 16 Apr 2023 13:04:06 +0000 (+0100)
Subject: (no commit message)
X-Git-Tag: opf_rfc_ls009_v1~10
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=a963b619a40b002a7f3a63686b954ddc2fdf5a9e;p=libreriscv.git

---

diff --git a/openpower/sv/remap.mdwn b/openpower/sv/remap.mdwn
index bed7cdf6f..fe2055661 100644
--- a/openpower/sv/remap.mdwn
+++ b/openpower/sv/remap.mdwn
@@ -338,7 +338,8 @@ Vector Reduce Mode issues a deterministic tree-reduction schedule to the underly
 
 In Horizontal-First Mode, Vector-result reduction **requires**
 the destination to be a Vector, which will be used to store
-intermediary results.
+intermediary results, in order to achieve a correct final
+result.
 
 Given that the tree-reduction schedule is deterministic,
 Interrupts and exceptions
@@ -409,7 +410,9 @@ It may be better to perform a pre-copy
 of the values, compressing them (VREDUCE-style) into a contiguous block,
 which will guarantee that the result goes into the very first element
 of the destination vector, in which case clearly no follow-up
-predicated vector-to-scalar MV operation is needed.
+predicated vector-to-scalar MV operation is needed. A VREDUCE effect
+is achieved by setting just a source predicate mask on Twin-Predicated
+operations.
 
 **Usage conditions**