From: Shriya Sharma <shriya@redsemiconductor.com>
Date: Mon, 8 Jan 2024 13:49:05 +0000 (+0000)
Subject: addedd code for pospopcount
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=1b57b8363cf2a468dd4c33814e336097861fbbbe;p=libreriscv.git

addedd code for pospopcount
---

diff --git a/conferences/fosdem2024/fosdem2024_ddffirst/fosdem2024_ddffirst.tex b/conferences/fosdem2024/fosdem2024_ddffirst/fosdem2024_ddffirst.tex
index dcbd7886a..ef907759b 100644
--- a/conferences/fosdem2024/fosdem2024_ddffirst/fosdem2024_ddffirst.tex
+++ b/conferences/fosdem2024/fosdem2024_ddffirst/fosdem2024_ddffirst.tex
@@ -181,34 +181,17 @@ function op\_cmpi(BA, RA, SI) # cmpi not vector-cmpi!
 		\item "TODO
   \end{itemize}
 }
-\frame{\frametitle{Pospopcount}
-	\begin{semiverbatim}
-	 // Copyright (c) 2020 Robert Clausecker <fuz@fuz.su>
-	// count8 reference implementation for tests.  Do not alter.
-	func count8safe(counts *[8]int, buf []uint8) {
-		for i := range buf {
-			for j := 0; j < 8; j++ {
-				counts[j] += int(buf[i] >> j & 1)
-			}
-		}
-	}
+\frame{\frametitle{Pospopcount.s}
 
-   A simple but still hardware-paralleliseable SVP64 assembler for 8-bit input values (count8safe) is as follows:
-
-	mtspr 9, 3                 # move r3 to CTR
-	setvl 3,0,8,0,1,1          # set MVL=8, VL=r3=MIN(MVL,CTR)
-	# load VL bytes (update r4 addr) but compressed (dw=8)
-	addi 6, 0, 0               # initialise all 64-bits of r6 to zero
-	sv.lbzu/pi/dw=8 *6, 1(4)   # should be /lf here as well
-	# gather performs the transpose (which gets us to positional..)
-	gbbd 8,6
-	# now those bits have been turned around, popcount and sum them
-	setvl 0,0,8,0,1,1          # set MVL=VL=8
-	sv.popcntd/sw=8 *24,*8     # do the (now transposed) popcount
-	sv.add *16,*16,*24         # and accumulate in results
-	# branch back if CTR still non-zero. works even though VL=8
-	sv.bc/all 16, *0, -0x28   # reduce CTR by VL and stop if -ve
-	\end{semiverbatim}
+\lstinputlisting[language={}]{pospopcount.s}
+
+}
+
+}
+
+\frame{\frametitle{Pospopcount.c}
+
+\lstinputlisting[language={}]{pospopcount.c}
 
 }
 
@@ -221,7 +204,7 @@ function op\_cmpi(BA, RA, SI) # cmpi not vector-cmpi!
 
 \frame{\frametitle{strncpy assembler}
 
-\lstinputlisting[language={}]{\strncpy.s}
+\lstinputlisting[language={}]{strncpy.s}
 
 }