From: lkcl <lkcl@web>
Date: Thu, 30 Mar 2023 00:01:44 +0000 (+0100)
Subject: (no commit message)
X-Git-Tag: opf_rfc_ls012_v1~217
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=996ecc9a41faa198e8b6d50a9755ec20caad4328;p=libreriscv.git

---

diff --git a/openpower/sv/rfc/ls010.mdwn b/openpower/sv/rfc/ls010.mdwn
index 541fffb50..3ed1b9876 100644
--- a/openpower/sv/rfc/ls010.mdwn
+++ b/openpower/sv/rfc/ls010.mdwn
@@ -1019,6 +1019,11 @@ such as crand, cror or [[sv/cr_int_predication]] crweirder may be used,
 and ffirst applied to the crop instead of to the arithmetic vector. Note
 that crops are covered by the [[sv/cr_ops]] Mode format.
 
+Use of Fail-on-first with Vertical-First Mode is not prohibited but is
+not really recommended.  The effect of truncating VL
+may have unintended and unexpected consequences on subsequent instructions.
+VLi set will be fine: it is when VLi is clear that problems may be faced.
+
 *Programmer's note: `VLi` is only accessible in normal operations which in
 turn limits the CR field bit-testing to only `EQ/NE`.  [[sv/cr_ops]] are
 not so limited.  Thus it is possible to use for example `sv.cror/ff=gt/vli