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--- intro_example:loops [2022/05/13 13:20] – rajit
+++ intro_example:loops [2025/08/24 16:48] (current) – [Array, loops and selection] rajit
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 ====== Array, loops and selection ======
 Complex datapath designs are often designed with array of simpler cells. The following example show how to create array of simple cells and connect them using loop constructs in ACT.
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   ( i : 8 : fa[i](a[i], b[i], c[i], s[i], c[i+1]);)
 }
+</code>
+In this example we assume that ''adder.act'' has a full adder definition with a prototype that looks like this:
+<code act>
+defproc fulladder (bool? a, b, ci; bool! s, co)
+{ ... }
 </code>
@@ Line 85: / Line 93: @@
 Depending on the value of index ''i'', input ''x0''/''x1'' are connected to output ''y'' or ''z''. If ''i'' is even, ''x0'' is connected to ''y'' and ''x1'' is connected to ''z''. If ''i'' is odd, ''x0'' is connected to ''z'' and ''x1'' is connected to ''y''.
+====== General loops ======
+The parenthesis-based syntax is a compact way to describe simple loop-based replication. If a more complex approach is needed, then a generalized while loop syntax is also available. The selection example earlier could also be re-written as follows:
+<code act>
+import "gates.act";
+defproc select (bool x0[8], x1[8]; bool y[8], z[8])
+{
+    pint i;
+    i = 0;
+    *[ i < 8 -> x0[i] = y[i]; x1[i] = z[i];
+                x0[i+1] = z[i+1]; x1[i+1] = y[i+1];
+                i = i + 2;
+    ]
+}
+</code>