From e152fbbef19f5169b075779c4cd3c34e913d7315 Mon Sep 17 00:00:00 2001
From: hneemann <helmut.neemann@arcor.de>
Date: Sat, 13 Jul 2019 09:28:22 +0200
Subject: [PATCH] improved the barrel shifter

---
 src/main/dig/generic/barrelShifter/Test.dig   | 140 +++++++++++++++---
 .../generic/barrelShifter/barrelShifter.dig   |  12 +-
 .../shift-fixed-arith-right-inc.dig           |   8 +-
 .../barrelShifter/shift-fixed-left-inc.dig    |   8 +-
 .../barrelShifter/shift-fixed-right-inc.dig   |   8 +-
 .../dig/generic/barrelShifter/shift-inc.dig   |  12 +-
 .../test/vhdl/barrelShifter/TestLeft32.dig    |   2 +-
 .../dig/test/vhdl/barrelShifter/TestLeft8.dig |   2 +-
 .../test/vhdl/barrelShifter/TestRight8.dig    |   2 +-
 .../vhdl/barrelShifter/TestRightArith16.dig   |   2 +-
 .../test/vhdl/barrelShifter/barrelShifter.dig |  41 +++--
 .../shift-fixed-arith-right-inc.dig           |   8 +-
 .../barrelShifter/shift-fixed-left-inc.dig    |   8 +-
 .../barrelShifter/shift-fixed-right-inc.dig   |   8 +-
 .../dig/test/vhdl/barrelShifter/shift-inc.dig |  68 +++------
 15 files changed, 189 insertions(+), 140 deletions(-)

diff --git a/src/main/dig/generic/barrelShifter/Test.dig b/src/main/dig/generic/barrelShifter/Test.dig
index 9e9c29f7f..cec54c916 100644
--- a/src/main/dig/generic/barrelShifter/Test.dig
+++ b/src/main/dig/generic/barrelShifter/Test.dig
@@ -371,12 +371,100 @@ end loop</dataString>
       </elementAttributes>
       <pos x="580" y="1020"/>
     </visualElement>
+    <visualElement>
+      <elementName>Out</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>D^64</string>
+        </entry>
+        <entry>
+          <string>Bits</string>
+          <int>64</int>
+        </entry>
+        <entry>
+          <string>intFormat</string>
+          <intFormat>bin</intFormat>
+        </entry>
+      </elementAttributes>
+      <pos x="740" y="-120"/>
+    </visualElement>
+    <visualElement>
+      <elementName>In</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>D^64_in</string>
+        </entry>
+        <entry>
+          <string>Bits</string>
+          <int>64</int>
+        </entry>
+        <entry>
+          <string>intFormat</string>
+          <intFormat>bin</intFormat>
+        </entry>
+        <entry>
+          <string>InDefault</string>
+          <value v="1" z="false"/>
+        </entry>
+      </elementAttributes>
+      <pos x="160" y="-140"/>
+    </visualElement>
+    <visualElement>
+      <elementName>In</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>sh^64</string>
+        </entry>
+        <entry>
+          <string>Bits</string>
+          <int>6</int>
+        </entry>
+      </elementAttributes>
+      <pos x="380" y="-100"/>
+    </visualElement>
+    <visualElement>
+      <elementName>barrelShifter.dig</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>64 bit, left</string>
+        </entry>
+        <entry>
+          <string>generic</string>
+          <string>dataBits := 64;
+direction := &quot;left&quot;;</string>
+        </entry>
+      </elementAttributes>
+      <pos x="420" y="-140"/>
+    </visualElement>
+    <visualElement>
+      <elementName>Testcase</elementName>
+      <elementAttributes>
+        <entry>
+          <string>Label</string>
+          <string>64 bit, left</string>
+        </entry>
+        <entry>
+          <string>Testdata</string>
+          <testData>
+            <dataString>D^64_in sh^64 D^64
+loop(n,64) 
+   1     (n)  (1&lt;&lt;n)
+end loop
+
+loop(n,64) 
+   7     (n)  (7&lt;&lt;n)
+end loop</dataString>
+          </testData>
+        </entry>
+      </elementAttributes>
+      <pos x="580" y="-60"/>
+    </visualElement>
   </visualElements>
   <wires>
-    <wire>
-      <p1 x="160" y="400"/>
-      <p2 x="420" y="400"/>
-    </wire>
     <wire>
       <p1 x="480" y="960"/>
       <p2 x="740" y="960"/>
@@ -386,13 +474,37 @@ end loop</dataString>
       <p2 x="740" y="160"/>
     </wire>
     <wire>
-      <p1 x="380" y="180"/>
-      <p2 x="420" y="180"/>
+      <p1 x="380" y="-100"/>
+      <p2 x="420" y="-100"/>
     </wire>
     <wire>
       <p1 x="480" y="420"/>
       <p2 x="740" y="420"/>
     </wire>
+    <wire>
+      <p1 x="480" y="680"/>
+      <p2 x="740" y="680"/>
+    </wire>
+    <wire>
+      <p1 x="160" y="-140"/>
+      <p2 x="420" y="-140"/>
+    </wire>
+    <wire>
+      <p1 x="160" y="140"/>
+      <p2 x="420" y="140"/>
+    </wire>
+    <wire>
+      <p1 x="160" y="940"/>
+      <p2 x="420" y="940"/>
+    </wire>
+    <wire>
+      <p1 x="160" y="400"/>
+      <p2 x="420" y="400"/>
+    </wire>
+    <wire>
+      <p1 x="380" y="180"/>
+      <p2 x="420" y="180"/>
+    </wire>
     <wire>
       <p1 x="160" y="660"/>
       <p2 x="420" y="660"/>
@@ -401,26 +513,18 @@ end loop</dataString>
       <p1 x="380" y="980"/>
       <p2 x="420" y="980"/>
     </wire>
+    <wire>
+      <p1 x="480" y="-120"/>
+      <p2 x="740" y="-120"/>
+    </wire>
     <wire>
       <p1 x="380" y="440"/>
       <p2 x="420" y="440"/>
     </wire>
-    <wire>
-      <p1 x="480" y="680"/>
-      <p2 x="740" y="680"/>
-    </wire>
-    <wire>
-      <p1 x="160" y="140"/>
-      <p2 x="420" y="140"/>
-    </wire>
     <wire>
       <p1 x="380" y="700"/>
       <p2 x="420" y="700"/>
     </wire>
-    <wire>
-      <p1 x="160" y="940"/>
-      <p2 x="420" y="940"/>
-    </wire>
   </wires>
   <measurementOrdering/>
 </circuit>
\ No newline at end of file
diff --git a/src/main/dig/generic/barrelShifter/barrelShifter.dig b/src/main/dig/generic/barrelShifter/barrelShifter.dig
index 8f26a207d..510601e58 100644
--- a/src/main/dig/generic/barrelShifter/barrelShifter.dig
+++ b/src/main/dig/generic/barrelShifter/barrelShifter.dig
@@ -30,9 +30,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="500" y="140"/>
@@ -54,9 +52,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="400" y="120"/>
@@ -74,9 +70,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=bitsNeededFor(args.dataBits-1);
-}</string>
+          <string>this.Bits=bitsNeededFor(args.dataBits-1);</string>
         </entry>
       </elementAttributes>
       <pos x="400" y="160"/>
diff --git a/src/main/dig/generic/barrelShifter/shift-fixed-arith-right-inc.dig b/src/main/dig/generic/barrelShifter/shift-fixed-arith-right-inc.dig
index 73e80f1b8..aa65cf86c 100644
--- a/src/main/dig/generic/barrelShifter/shift-fixed-arith-right-inc.dig
+++ b/src/main/dig/generic/barrelShifter/shift-fixed-arith-right-inc.dig
@@ -35,9 +35,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="600" y="140"/>
@@ -55,9 +53,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="280" y="120"/>
diff --git a/src/main/dig/generic/barrelShifter/shift-fixed-left-inc.dig b/src/main/dig/generic/barrelShifter/shift-fixed-left-inc.dig
index 4539fdd39..edff6777c 100644
--- a/src/main/dig/generic/barrelShifter/shift-fixed-left-inc.dig
+++ b/src/main/dig/generic/barrelShifter/shift-fixed-left-inc.dig
@@ -35,9 +35,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="600" y="140"/>
@@ -55,9 +53,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="300" y="120"/>
diff --git a/src/main/dig/generic/barrelShifter/shift-fixed-right-inc.dig b/src/main/dig/generic/barrelShifter/shift-fixed-right-inc.dig
index 7d7a63232..ed307c078 100644
--- a/src/main/dig/generic/barrelShifter/shift-fixed-right-inc.dig
+++ b/src/main/dig/generic/barrelShifter/shift-fixed-right-inc.dig
@@ -35,9 +35,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="600" y="140"/>
@@ -55,9 +53,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="300" y="120"/>
diff --git a/src/main/dig/generic/barrelShifter/shift-inc.dig b/src/main/dig/generic/barrelShifter/shift-inc.dig
index 11263a654..393b19585 100644
--- a/src/main/dig/generic/barrelShifter/shift-inc.dig
+++ b/src/main/dig/generic/barrelShifter/shift-inc.dig
@@ -42,9 +42,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="540" y="140"/>
@@ -66,9 +64,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="180" y="100"/>
@@ -86,9 +82,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.shiftBits);
-}</string>
+          <string>this.Bits=int(args.shiftBits);</string>
         </entry>
       </elementAttributes>
       <pos x="180" y="140"/>
diff --git a/src/test/resources/dig/test/vhdl/barrelShifter/TestLeft32.dig b/src/test/resources/dig/test/vhdl/barrelShifter/TestLeft32.dig
index c98c4c43c..e148cf7ce 100644
--- a/src/test/resources/dig/test/vhdl/barrelShifter/TestLeft32.dig
+++ b/src/test/resources/dig/test/vhdl/barrelShifter/TestLeft32.dig
@@ -67,7 +67,7 @@
         <entry>
           <string>generic</string>
           <string>dataBits := 32;
-dir := &quot;left&quot;;</string>
+direction := &quot;left&quot;;</string>
         </entry>
       </elementAttributes>
       <pos x="420" y="120"/>
diff --git a/src/test/resources/dig/test/vhdl/barrelShifter/TestLeft8.dig b/src/test/resources/dig/test/vhdl/barrelShifter/TestLeft8.dig
index 4c1045fd2..713136700 100644
--- a/src/test/resources/dig/test/vhdl/barrelShifter/TestLeft8.dig
+++ b/src/test/resources/dig/test/vhdl/barrelShifter/TestLeft8.dig
@@ -67,7 +67,7 @@
         <entry>
           <string>generic</string>
           <string>dataBits := 8;
-dir := &quot;left&quot;;</string>
+direction := &quot;left&quot;;</string>
         </entry>
       </elementAttributes>
       <pos x="420" y="400"/>
diff --git a/src/test/resources/dig/test/vhdl/barrelShifter/TestRight8.dig b/src/test/resources/dig/test/vhdl/barrelShifter/TestRight8.dig
index e28480ab9..f640d78c4 100644
--- a/src/test/resources/dig/test/vhdl/barrelShifter/TestRight8.dig
+++ b/src/test/resources/dig/test/vhdl/barrelShifter/TestRight8.dig
@@ -67,7 +67,7 @@
         <entry>
           <string>generic</string>
           <string>dataBits := 8;
-dir := &quot;right&quot;;</string>
+direction := &quot;right&quot;;</string>
         </entry>
       </elementAttributes>
       <pos x="420" y="660"/>
diff --git a/src/test/resources/dig/test/vhdl/barrelShifter/TestRightArith16.dig b/src/test/resources/dig/test/vhdl/barrelShifter/TestRightArith16.dig
index 8fff8154f..76d5c78ac 100644
--- a/src/test/resources/dig/test/vhdl/barrelShifter/TestRightArith16.dig
+++ b/src/test/resources/dig/test/vhdl/barrelShifter/TestRightArith16.dig
@@ -67,7 +67,7 @@
         <entry>
           <string>generic</string>
           <string>dataBits := 16;
-dir := &quot;arith&quot;;</string>
+direction := &quot;arith&quot;;</string>
         </entry>
       </elementAttributes>
       <pos x="420" y="940"/>
diff --git a/src/test/resources/dig/test/vhdl/barrelShifter/barrelShifter.dig b/src/test/resources/dig/test/vhdl/barrelShifter/barrelShifter.dig
index 5f7d26772..510601e58 100644
--- a/src/test/resources/dig/test/vhdl/barrelShifter/barrelShifter.dig
+++ b/src/test/resources/dig/test/vhdl/barrelShifter/barrelShifter.dig
@@ -30,9 +30,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="500" y="140"/>
@@ -54,9 +52,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="400" y="120"/>
@@ -74,9 +70,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=bitsNeededFor(args.dataBits-1);
-}</string>
+          <string>this.Bits=bitsNeededFor(args.dataBits-1);</string>
         </entry>
       </elementAttributes>
       <pos x="400" y="160"/>
@@ -86,13 +80,28 @@
       <elementAttributes>
         <entry>
           <string>generic</string>
-          <string>dataBits:=16;
-shiftBits:=int(4);
-dir:=&quot;left&quot;;
-if (isPresent(args)) {
-  dir=args.dir;
-  dataBits=args.dataBits;
-  shiftBits=bitsNeededFor(args.dataBits-1);
+          <string>if (isPresent(args)) {
+
+    if (args.direction=&quot;right&quot;) {
+        export circuit:=&quot;shift-fixed-right-inc.dig&quot;;
+    } else {
+        if (args.direction=&quot;arith&quot;) {
+            export circuit:=&quot;shift-fixed-arith-right-inc.dig&quot;;
+        } else {
+            if (args.direction=&quot;left&quot;) {
+                export circuit:=&quot;shift-fixed-left-inc.dig&quot;;
+            } else {
+                panic(&quot;only \&quot;left\&quot;, \&quot;right\&quot; or \&quot;arith\&quot; is allowed as direction, not \&quot;&quot;+args.dir+&quot;\&quot;!&quot;);
+            }
+        }
+    }
+
+    export shiftBits:=bitsNeededFor(args.dataBits-1);
+} else {
+    // used if circuit is started as the main circuit
+    export circuit:=&quot;shift-fixed-left-inc.dig&quot;;
+    export dataBits:=16;
+    export shiftBits:=int(4);
 }</string>
         </entry>
       </elementAttributes>
diff --git a/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-arith-right-inc.dig b/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-arith-right-inc.dig
index 73e80f1b8..aa65cf86c 100644
--- a/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-arith-right-inc.dig
+++ b/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-arith-right-inc.dig
@@ -35,9 +35,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="600" y="140"/>
@@ -55,9 +53,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="280" y="120"/>
diff --git a/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-left-inc.dig b/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-left-inc.dig
index 4539fdd39..edff6777c 100644
--- a/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-left-inc.dig
+++ b/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-left-inc.dig
@@ -35,9 +35,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="600" y="140"/>
@@ -55,9 +53,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="300" y="120"/>
diff --git a/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-right-inc.dig b/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-right-inc.dig
index 7d7a63232..ed307c078 100644
--- a/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-right-inc.dig
+++ b/src/test/resources/dig/test/vhdl/barrelShifter/shift-fixed-right-inc.dig
@@ -35,9 +35,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="600" y="140"/>
@@ -55,9 +53,7 @@
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="300" y="120"/>
diff --git a/src/test/resources/dig/test/vhdl/barrelShifter/shift-inc.dig b/src/test/resources/dig/test/vhdl/barrelShifter/shift-inc.dig
index 6b5d45a4f..393b19585 100644
--- a/src/test/resources/dig/test/vhdl/barrelShifter/shift-inc.dig
+++ b/src/test/resources/dig/test/vhdl/barrelShifter/shift-inc.dig
@@ -13,22 +13,13 @@
       <elementAttributes>
         <entry>
           <string>generic</string>
-          <string>dataBits:=16;
-shift:=8;
-if (isPresent(args)) {
-    dataBits = args.dataBits;
-    shift = 1&lt;&lt;(args.shiftBits-1);
-    if (args.dir=&quot;right&quot;) {
-        setCircuit(&quot;shift-fixed-right-inc.dig&quot;);
-    } else {
-        if (args.dir=&quot;arith&quot;) {
-            setCircuit(&quot;shift-fixed-arith-right-inc.dig&quot;);
-        } else {
-            if (args.dir!=&quot;left&quot;) {
-                panic(&quot;only \&quot;left\&quot;, \&quot;right\&quot; or \&quot;arith\&quot; is allowed as direction, not \&quot;&quot;+args.dir+&quot;\&quot;!&quot;);
-            }
-        }
-    }
+          <string>if (isPresent(args)) {
+    export shift := 1&lt;&lt;(args.shiftBits-1);
+    setCircuit(args.circuit);
+} else {
+    // used if circuit is started as the main circuit
+    export dataBits:=16;
+    export shift:=8;
 }</string>
         </entry>
       </elementAttributes>
@@ -51,9 +42,7 @@ if (isPresent(args)) {
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="540" y="140"/>
@@ -75,9 +64,7 @@ if (isPresent(args)) {
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.dataBits);
-}</string>
+          <string>this.Bits=int(args.dataBits);</string>
         </entry>
       </elementAttributes>
       <pos x="180" y="100"/>
@@ -95,9 +82,7 @@ if (isPresent(args)) {
         </entry>
         <entry>
           <string>generic</string>
-          <string>if (isPresent(args)) {
-  this.Bits=int(args.shiftBits);
-}</string>
+          <string>this.Bits=int(args.shiftBits);</string>
         </entry>
       </elementAttributes>
       <pos x="180" y="140"/>
@@ -107,31 +92,18 @@ if (isPresent(args)) {
       <elementAttributes>
         <entry>
           <string>generic</string>
-          <string>dataBits:=16;
-shiftBits:=3;
-dir:=&quot;left&quot;;
-if (isPresent(args)) {
-  dataBits = args.dataBits;
-  shiftBits = args.shiftBits-1;
-  dir=args.dir;
-  if (args.shiftBits=2) {
-
-    export shift := 1;
-    if (args.dir=&quot;right&quot;) {
-        setCircuit(&quot;shift-fixed-right-inc.dig&quot;);
+          <string>if (isPresent(args)) {
+    if (args.shiftBits=2) {
+       export shift := 1;
+       setCircuit(args.circuit);
     } else {
-        if (args.dir=&quot;arith&quot;) {
-            setCircuit(&quot;shift-fixed-arith-right-inc.dig&quot;);
-        } else {
-            if (args.dir!=&quot;left&quot;) {
-                panic(&quot;only \&quot;left\&quot;, \&quot;right\&quot; or \&quot;arith\&quot; is allowed as direction, not \&quot;&quot;+args.dir+&quot;\&quot;!&quot;);
-            }
-            setCircuit(&quot;shift-fixed-left-inc.dig&quot;);
-        }
+        export shiftBits := args.shiftBits-1;
     }
-
-
-  }
+} else {
+    // used if circuit is started as the main circuit
+    export dataBits:=16;
+    export shiftBits:=3;
+    export circuit:=&quot;shift-fixed-left-inc.dig&quot;;
 }</string>
         </entry>
       </elementAttributes>