From 44bec8dfc4112ff102f54d6bf1c67497ddc5bdd4 Mon Sep 17 00:00:00 2001
From: lkcl <lkcl@web>
Date: Sun, 10 Jan 2021 01:16:43 +0000
Subject: [PATCH]

---
 openpower/sv/bitmanip.mdwn | 63 +++++++++++++++++++-------------------
 1 file changed, 31 insertions(+), 32 deletions(-)

diff --git a/openpower/sv/bitmanip.mdwn b/openpower/sv/bitmanip.mdwn
index 86acf073d..ebee70ac9 100644
--- a/openpower/sv/bitmanip.mdwn
+++ b/openpower/sv/bitmanip.mdwn
@@ -9,7 +9,7 @@
 
 # vector bit deposit
 
-vpdepd VRT,VRA,VRB
+vpdepd VRT,VRA,VRB, identical to RV bitmamip bdep
 
     do while(m < 64)
        if VSR[VRB+32].dword[i].bit[63-m]=1 then do
@@ -18,10 +18,39 @@ vpdepd VRT,VRA,VRB
           k = k + 1
        m = m + 1
 
+```
+
+uint_xlen_t bdep(uint_xlen_t RA, uint_xlen_t RB)
+{
+    uint_xlen_t r = 0;
+    for (int i = 0, j = 0; i < XLEN; i++)
+        if ((RB >> i) & 1) {
+            if ((RA >> j) & 1)
+                r |= uint_xlen_t(1) << i;
+            j++;
+        }
+    return r;
+}
+
+```
+
 # vector bit extract
 
-other way round
+other way round: identical to RV bext
 
+```
+uint_xlen_t bext(uint_xlen_t RA, uint_xlen_t RB)
+{
+    uint_xlen_t r = 0;
+    for (int i = 0, j = 0; i < XLEN; i++)
+        if ((RB >> i) & 1) {
+            if ((RA >> i) & 1)
+                r |= uint_xlen_t(1) << j;
+            j++;
+        }
+    return r;
+}
+```
 # ternary bitops
 
 for every bit perform a lookup into a table using an 8bit immediate
@@ -260,36 +289,6 @@ uint_xlen_t cmix(uint_xlen_t RA, uint_xlen_t RB, uint_xlen_t RC) {
 }
 ```
 
-# bdep, bext
-
-based on RV bitmanip
-
-```
-uint_xlen_t bext(uint_xlen_t RA, uint_xlen_t RB)
-{
-    uint_xlen_t r = 0;
-    for (int i = 0, j = 0; i < XLEN; i++)
-        if ((RB >> i) & 1) {
-            if ((RA >> i) & 1)
-                r |= uint_xlen_t(1) << j;
-            j++;
-        }
-    return r;
-}
-uint_xlen_t bdep(uint_xlen_t RA, uint_xlen_t RB)
-{
-    uint_xlen_t r = 0;
-    for (int i = 0, j = 0; i < XLEN; i++)
-        if ((RB >> i) & 1) {
-            if ((RA >> j) & 1)
-                r |= uint_xlen_t(1) << i;
-            j++;
-        }
-    return r;
-}
-
-```
-
 # carryless mul
 
 based on RV bitmanip
-- 
2.30.2