documentation changes; added bench/stagediv.fs

Author: AntonErtl

bench/stagediv.fs

@@ -0,0 +1,52 @@
+\ measure the two words given in the manual
+
+\ invoke with gforth-fast -e "1 7" bench/stagediv.fs
+\ where 1 (or 2) is the number of stages, and 7 is the u for array/
+
+\ for j in 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 100 2000; do echo $j; for i in 1 2; do perf stat -e cycles:u gforth-fast -e "$i $j" bench/stagediv.fs |& grep cycles:u; done; done
+
+
+constant u
+constant stages
+
+
+stages 1 = [if]
+: array/ ( addr u n -- )
+  -rot cells bounds u+do
+    i @ over / i !
+  1 cells +loop
+  drop ;
+[then]
+stages 2 = [if]
+: array/ ( addr u n -- )
+  {: | reci[ staged/-size ] :}
+  reci[ /f-stage1m
+  cells bounds u+do
+    i @ reci[ /f-stage2m i !
+  1 cells +loop ;
+[then]
+
+#2000 constant #elems
+create orig #elems cells allot
+create working #elems cells allot
+
+: init ( -- )
+    1000000 #elems 0 do
+        dup orig i th ! 10 +
+    loop ;
+
+init
+
+: bench ( -- )
+    10000000 #elems / 0 ?do
+        orig working #elems cells move
+        working #elems u / 0 ?do
+            dup u 3 array/
+            u cells +
+        loop
+        drop
+    loop ;
+bench
+bye
+        
+