From 3d16e8e035024028cac57572009f74d2159b3ed4 Mon Sep 17 00:00:00 2001 From: lkcl Date: Wed, 16 Dec 2020 17:15:18 +0000 Subject: [PATCH] --- openpower/sv/svp_rewrite/svp64.mdwn | 2 ++ 1 file changed, 2 insertions(+) diff --git a/openpower/sv/svp_rewrite/svp64.mdwn b/openpower/sv/svp_rewrite/svp64.mdwn index f36d6fb4c..775eae2ce 100644 --- a/openpower/sv/svp_rewrite/svp64.mdwn +++ b/openpower/sv/svp_rewrite/svp64.mdwn @@ -12,6 +12,8 @@ counting up as you move to the LSB end). All bit ranges are inclusive (so 64-bit instructions are split into two 32-bit words, the prefix and the suffix. The prefix always comes before the suffix in PC order. +SVP64 is designed so that when the prefix is all zeros, no effect or influence occurs (no augmentation) such that all standard OpenPOWER v3.B instructions may be active at that time, in full. The corollary is that when the SV prefix is nonzero, alternative meanings may be given to all and any instructions. + ## Definition of Reserved in this spec. For the new fields added in SVP64, instructions that have any of their fields set to a reserved value must cause an illegal instruction trap, to allow emulation of future instruction sets. -- 2.30.2