From d0a2fff0966c6c28508bf06e417b215b9ee89e47 Mon Sep 17 00:00:00 2001
From: alexmadison <git@mdsn.co.uk>
Date: Thu, 3 Mar 2022 10:52:29 +0100
Subject: [PATCH] arbiter init with or2s

---
 dataflow_neuro/treegates.act | 112 +++++++++++++++++++++++++++++++++++
 1 file changed, 112 insertions(+)

diff --git a/dataflow_neuro/treegates.act b/dataflow_neuro/treegates.act
index 991d79d..c1e8294 100644
--- a/dataflow_neuro/treegates.act
+++ b/dataflow_neuro/treegates.act
@@ -416,5 +416,117 @@ defproc sigbuf (bool? in; bool! out[N]; power supply)
    ]
    (i:1..N-1:out[i]=out[0];)
 }
+
+
+
+
+/*
+ * Build a completion tree using a combination of 2-input and 3-input
+ * arbiters
+ */
+export template<pint N>
+defproc arbtree (bool? in[N]; bool! out; power supply)
+{
+  bool tout;
+
+  { N > 0 : "What?" };
+
+  pint i, end, j;
+  i = 0;
+  end = N-1;
+
+  pint arbCount;
+  arbCount = 0;
+  /* Pre"calculate" the number of C cells required, look below if confused */
+  *[ i != end ->
+     j = 0;
+     *[ i <= end ->
+        j = j + 1;
+        [i = end ->
+          i = end+1;
+        [] i+1 = end ->
+          i = end+1;
+          arbCount = arbCount +1;
+        [] else ->
+          i = i + 2;
+          arbCount = arbCount +1;
+        ]
+      ]
+      /*-- update range that has to be combined --*/
+      // i = end+1;
+      end = end+j;
+  ]
+
+  /* array that holds ALL the nodes in the completion tree */
+  bool tmp[end+1];
+
+  
+  // Connecting the first nodes to the input
+  (l:N:
+    tmp[l] = in[l];
+    )
+
+  /* array to hold the actual C-elments, either A2C or A3C */
+  [arbCount > 0 ->
+    OR2_X1 arbs[arbCount];
+  ]
+
+
+  (h:arbCount:arbs[h].vdd = supply.vdd;)
+  (h:arbCount:arbs[h].vss = supply.vss;)
+
+  /* Reset the variables we just stole lol */
+  i = 0;
+  end = N-1;
+  j = 0;
+  pint arbIndex = 0;
+
+  /* Invariant: i <= end */
+
+  *[ i != end ->
+     /* 
+      * Invariant: tmp[i..end] has the current signals that need to be
+      * combined together, and "isinv" specifies if they are the inverted
+      * sense or not
+      */
+   j = 0;
+   *[ i <= end ->
+        /*-- there are still signals that need to be combined --*/
+      j = j + 1;
+      [ i = end ->
+        /*-- last piece: pipe input through to next layer --*/
+        tmp[end+j] = tmp[i];
+        i = end+1;
+      [] i+1 = end ->
+        /*-- last piece: use either a 2 input C-element --*/
+        arbs[arbIndex].a = tmp[i];
+        arbs[arbIndex].b = tmp[i+1];
+        arbs[arbIndex].y = tmp[end+j];
+        arbIndex = arbIndex +1;
+        i = end+1;
+      [] else ->
+        /*-- more to come; so use a two input C-element --*/
+        arbs[arbIndex].a = tmp[i];
+        arbs[arbIndex].b = tmp[i+1];
+        arbs[arbIndex].y = tmp[end+j];
+        arbIndex = arbIndex +1;
+        i = i + 2;
+        ]
+      ]
+        /*-- update range that has to be combined --*/
+     i = end+1;
+     end = end+j;
+     j = 0;
+   ]
+  
+  out = tmp[end];
+  
+}
+
+
+
+
+
+
 }}