From: lkcl <lkcl@web>
Date: Thu, 2 Sep 2021 19:56:20 +0000 (+0100)
Subject: (no commit message)
X-Git-Tag: DRAFT_SVP64_0_1~246
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=5cbd23c4a44726cdc8e4e29fe6f530401af84542;p=libreriscv.git

---

diff --git a/openpower/sv/ldst.mdwn b/openpower/sv/ldst.mdwn
index cc2161fc8..ff6159487 100644
--- a/openpower/sv/ldst.mdwn
+++ b/openpower/sv/ldst.mdwn
@@ -231,7 +231,10 @@ cache-inhibited LD should be performed, followed by a VSPLAT-augmented mv.
 
 ## LD/ST ffirst
 
-ffirst LD/ST to multiple pages via a Vectorised base is considered a security risk due to the abuse of probing multiple pages in rapid succession and getting feedback on which pages would fail.  Therefore in these special circumstances requesting ffirst with a vector base is instead interpreted as element-strided LD/ST.  See <https://bugs.libre-soc.org/show_bug.cgi?id=561>
+ffirst LD/ST to multiple pages via a Vectorised Index base is considered a security risk due to the abuse of probing multiple pages in rapid succession and getting feedback on which pages would fail.  Therefore in these special circumstances requesting ffirst on Indexed LD/ST is instead interpreted as element-strided LD/ST.  See <https://bugs.libre-soc.org/show_bug.cgi?id=561>
+
+    for(i = 0; i < VL; i++)
+        reg[rt + i] = mem[reg[ra] + i * reg[rb]];
 
 High security implementations where any kind of speculative probing
 of memory pages is considered a risk should take advantage of the fact that