Added missing fragments for rolling unsigned words. Added test demonstrating Unroller problem.

src/main/fragment/vwuz1=vwuz1_rol_5.asm

@@ -0,0 +1,10 @@
+asl {z1}
+rol {z1}+1
+asl {z1}
+rol {z1}+1
+asl {z1}
+rol {z1}+1
+asl {z1}
+rol {z1}+1
+asl {z1}
+rol {z1}+1

src/main/fragment/vwuz1=vwuz1_rol_7.asm

@@ -0,0 +1,14 @@
+asl {z1}
+rol {z1}+1
+asl {z1}
+rol {z1}+1
+asl {z1}
+rol {z1}+1
+asl {z1}
+rol {z1}+1
+asl {z1}
+rol {z1}+1
+asl {z1}
+rol {z1}+1
+asl {z1}
+rol {z1}+1

src/main/java/dk/camelot64/kickc/Compiler.java

@@ -344,19 +344,10 @@ public class Compiler {
       optimizations.add(new Pass2EliminateUnusedBlocks(program));
       if(!disableLoopHeadConstant) {
          optimizations.add(new PassNStatementIndices(program));
-         optimizations.add(() -> {
-            program.clearDominators();
-            return false;
-         });
-         optimizations.add(() -> {
-            program.clearLoopSet();
-            return false;
-         });
+         optimizations.add(() -> { program.clearDominators(); return false; });
+         optimizations.add(() -> { program.clearLoopSet(); return false; });
          optimizations.add(new Pass2LoopHeadConstantIdentification(program));
-         optimizations.add(() -> {
-            program.clearStatementIndices();
-            return false;
-         });
+         optimizations.add(() -> { program.clearStatementIndices(); return false; });
       }
       return optimizations;
    }

src/main/java/dk/camelot64/kickc/passes/Pass2LoopHeadConstantIdentification.java

@@ -104,6 +104,8 @@ public class Pass2LoopHeadConstantIdentification extends Pass2SsaOptimization {
                return blocks;
             };
 
+            //getLog().append("Unrolling Constant Loop Head " +loopHeadBlock.getLabel());
+
             // Copy the block and all statements - enter through the copy - finish through the original
             Unroller.UnrollStrategy unrollStrategy = new Unroller.UnrollStrategy() {
                @Override

src/main/java/dk/camelot64/kickc/passes/utils/Unroller.java

@@ -75,6 +75,7 @@ public class Unroller {
     * Ensure that variables defined inside and used outside the blocks to be copied has different versions in different successors blocks.
     */
    private void prepare() {
+      // TODO Handle variables modified inside called functions!
       for(VariableRef origVarRef : getVarsDefinedIn(unrollBlocks, program)) {
          // Find out if the variable is ever referenced outside the loop
          if(isReferencedOutside(origVarRef, unrollBlocks, program)) {
@@ -204,6 +205,7 @@ public class Unroller {
                   // Variable has no version in the predecessor block - add a new PHI and populate later!
                   VariableRef newVarRef = createNewVersion(doingVarRef);
                   predecessor.getPhiBlock().addPhiVariable(newVarRef);
+                  //program.getLog().append("Adding PHI for "+newVarRef+" to "+predecessor.getLabel());
                   varVersions.put(predecessor.getLabel(), newVarRef);
                   todo.put(predecessor.getLabel(), newVarRef);
                   predecessorVarRef = newVarRef;
@@ -211,6 +213,8 @@ public class Unroller {
                doingPhiVariable.setrValue(predecessor.getLabel(), predecessorVarRef);
             }
          }
+         //program.getLog().append("Completing PHI-functions...");
+         //program.getLog().append(program.getGraph().toString(program));
       }
    }
 

src/test/java/dk/camelot64/kickc/test/TestPrograms.java

@@ -36,6 +36,11 @@ public class TestPrograms {
    public TestPrograms() {
    }
 
+   //@Test
+   //public void testLoopheadProblem() throws IOException, URISyntaxException {
+   //   compileAndCompare("loophead-problem");
+   //}
+
    @Test
    public void testSwitch0() throws IOException, URISyntaxException {
       compileAndCompare("switch-0");
@@ -1638,7 +1643,7 @@ public class TestPrograms {
 
    //@Test
    //public void testRobozzle64() throws IOException, URISyntaxException {
-   //   compileAndCompare("complex/robozzle_c64/robozzle64", log());
+   //   compileAndCompare("complex/robozzle_c64/robozzle64", log().verboseSSAOptimize().verboseLoopUnroll());
    //}
 
    //@Test

src/test/kc/loophead-problem.kc

@@ -0,0 +1,23 @@
+// Demonstrates a problem where constant loophead unrolling results in an error
+// The result is a NullPointerException
+// The cause is that the Unroller does not handle the variable opcode correctly.
+// The Unroller gets the verwions for opcode wrong because it misses the fact that it is modified inside call to popup_selector()
+
+const byte* screen = $0400;
+
+byte opcode = 'a'; // Offending unroll variable
+
+void main() {
+    screen[40] = opcode;
+    popup_selector();
+    screen[41] = opcode;
+}
+
+void popup_selector() {
+	for (byte k = 0; k <= 2; k++) {
+		opcode = 'b';
+		screen[k] = opcode;
+	}
+}
+
+