From: lkcl Date: Mon, 21 Dec 2020 03:44:10 +0000 (+0000) Subject: (no commit message) X-Git-Tag: convert-csv-opcode-to-binary~1112 X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=a15444d510f34e0c79fb7afb76f91df29698e6d7;p=libreriscv.git --- diff --git a/openpower/sv/svp_rewrite/svp64.mdwn b/openpower/sv/svp_rewrite/svp64.mdwn index e2b893642..3bbdfabfc 100644 --- a/openpower/sv/svp_rewrite/svp64.mdwn +++ b/openpower/sv/svp_rewrite/svp64.mdwn @@ -624,7 +624,9 @@ Additional unusual capabilities of Twin Predication include a back-to-back version of VCOMPRESS-VEXPAND which is effectively the ability to do an ordered multiple VINSERT. -# CR Operations +# Appendix + +## CR Operations CRs are slightly more involved than INT or FP registers due to the possibility for indexing individual bits (crops BA/BB/BT). Again however @@ -632,7 +634,7 @@ the access pattern needs to be understandable in relation to v3.0B / v3.1B numbering, with a clear linear relationship and mapping existing when SV is applied. -## CR EXTRA mapping table and algorithm +### CR EXTRA mapping table and algorithm Numbering relationships for CR fields are already complex due to being in BE format (*the relationship is not clearly explained in the v3.0B @@ -690,7 +692,7 @@ batches of aligned 32-bit chunks (CR0-7, CR7-15). This is to greatly simplify internal design. If instructions are issued where CR Vectors do not start on a 32-bit aligned boundary, performance may be affected. -## CR fields as inputs/outputs of vector operations +### CR fields as inputs/outputs of vector operations CRs (or, the arithmetic operations associated with them) may be marked as Vectorised or Scalar. When Rc=1 in arithmetic operations that have no explicit EXTRA to cover the CR, the CR is Vectorised if the destination is Vectorised. Likewise if the destination is scalar then so is the CR. @@ -746,7 +748,7 @@ hindrance, regardless of the length of VL. (see [[discussion]]. some alternative schemes are described there) -## Table of CR fields +### Table of CR fields CR[i] is the notation used by the OpenPower spec to refer to CR field #i, so FP instructions with Rc=1 write to CR[1] aka SVCR1_000. @@ -762,7 +764,7 @@ overwhelm this one). [[svp64/cr_names]] -# Register Profiles +## Register Profiles **NOTE THIS TABLE SHOULD NO LONGER BE HAND EDITED** see for details.