From: Jacob Lifshay <programmerjake@gmail.com>
Date: Fri, 23 Sep 2022 03:36:39 +0000 (-0700)
Subject: link to pseudo-code in openpower-isa.git
X-Git-Tag: opf_rfc_ls005_v1~323
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=56e8cbd65cc4c37f29c9816d73fba59fad39db9c;p=libreriscv.git

link to pseudo-code in openpower-isa.git
---

diff --git a/openpower/prefix_codes.mdwn b/openpower/prefix_codes.mdwn
index f09760179..9bd0e0eb9 100644
--- a/openpower/prefix_codes.mdwn
+++ b/openpower/prefix_codes.mdwn
@@ -50,42 +50,7 @@ and so on for t[16..]
 
 Decoding a code word works by walking on the tree from the root to the children, matching each passed 0 or 1 to the next read input bit in RB in LSB to MSB order. When `t[i]` is set, then a valid code word was read and `i` is written to the next byte of output in RT in LSB to MSB order. When no set `t[i]` is encountered, and there are still input bits left, then the code word is >6-bits, so SO/OV/OV32 are set, and decoding stops.
 
-# [DRAFT] Prefix-code decode
-
-sorta-VA-Form
-
-* pcdec RT,RA,RB,RC,imm
-
-Pseudo-code:
-
-    tree[0:63] <- (RA)
-    in_bits[0:63] <- (RB)
-    in_pos <- (RC)
-    decoded_in_pos <- in_pos
-    output <- [0] * 64
-    out_byte <- 0
-    decoded[0:7] <- 1
-    overflow <- 0
-    do while in_pos <u 64
-        # walk the binary tree in `tree` from parent to the selected child
-        decoded <- decoded * 2 + in_bits[63 - in_pos]
-        in_pos <- in_pos + 1
-        if decoded >=u 64 then
-            overflow <- 1
-            break
-        if tree[63 - decoded] then
-            decoded_in_pos <- in_pos
-            output[56 - 8 * out_byte:63 - 8 * out_byte] <- decoded
-            decoded <- 1
-            out_byte <- out_byte + 1
-            if imm | (out_byte >=u 8) then
-                break
-    RT <- output
-    RS <- decoded_in_pos
-
-Special Registers Altered:
-
-    SO OV OV32
+[[!inline pages="openpower/isa/prefix_codes" quick="yes" raw="yes" ]]
 
 # [DRAFT] Prefix-code encode