From: lkcl <lkcl@web>
Date: Fri, 7 Apr 2023 20:36:23 +0000 (+0100)
Subject: (no commit message)
X-Git-Tag: opf_rfc_ls012_v1~88
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=306bbdafc2cf77af8a160ec7ff915a79ba74aecf;p=libreriscv.git

---

diff --git a/openpower/sv/rfc/ls012.mdwn b/openpower/sv/rfc/ls012.mdwn
index b3315f451..1ee99d542 100644
--- a/openpower/sv/rfc/ls012.mdwn
+++ b/openpower/sv/rfc/ls012.mdwn
@@ -14,5 +14,26 @@ of a borderline Vectoriseable Defined Word is `mv.swizzle` which
 only really becomes high-priority for Vector GPU and HPC Workloads,
 but has less merit as a Scalar-only operation.
 
+Instruction count guide and approximate priority order:
+
+* 6 - SVP64 Management [[ls008]] [[ls009]] [[ls010]]
+* 5 - CR weirds
+* 4 - INT<->FP mv [[ls006]]
+* 19 - GPR LD/ST-PostIncrement-Update (saves hugely in hot-loops) [[ls011]]
+* ~12 - FPR LD/ST-PostIncrement-Update (ditto) [[ls011]]
+* 2 - Float-Load-Immediate (always saves one LD L1/2/3 D-Cache op) [[ls002]]
+* 5 - Big-Integer Chained 3-in 2-out (64-bit Carry)
+* 6 - Bitmanip LUT2/3 operations. high cost high reward
+* 1 - fclass (Scalar variant of xvtstdcsp)
+* 5 - Audio-Video
+* 2 - Shift-and-Add (mitigates LD-ST-Shift; Cryptography e.g. twofish)
+* 2 - BMI group
+* 2 - GPU swizzle
+* 9 - FP DCT/FFT Butterfly (2/3-in 2-out)
+* ~9 Integer DCT/FFT Butterfly
+* 18 - Trigonometric (1-arg)
+* 15 - Transcendentals (1-arg)
+* 25 - Transcendentals (2-arg)
+
 [[!inline pages="openpower/sv/rfc/ls012/areas.mdwn" raw=yes ]]