Refactored more program data to be calculated on demand.

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

@@ -315,9 +315,9 @@ public class Compiler {
       List<PassStep> loopUnrolling = new ArrayList<>();
       loopUnrolling.add(new PassNStatementIndices(program));
       loopUnrolling.add(() -> { program.clearVariableReferenceInfos(); return false; });
-      loopUnrolling.add(new PassNStatementInfos(program));
+      loopUnrolling.add(() -> { program.clearStatementInfos(); return false; });
       loopUnrolling.add(() -> { program.clearDominators(); return false; });
-      loopUnrolling.add(new PassNLoopAnalysis(program));
+      loopUnrolling.add(() -> { program.clearLoopSet(); return false; });
       loopUnrolling.add(new Pass2LoopUnrollPhiPrepare(program));
       loopUnrolling.add(new Pass2LoopUnroll(program));
 
@@ -422,9 +422,8 @@ public class Compiler {
 
       //getLog().setVerboseLiveRanges(true);
 
-      new PassNStatementInfos(program).execute();
+      program.clearStatementInfos();
       program.clearVariableReferenceInfos();
-      new Pass3LiveRangesAnalysis(program).findLiveRanges();
       //getLog().append("CONTROL FLOW GRAPH - LIVE RANGES FOUND");
       //getLog().append(program.getGraph().toString(program));
       pass2AssertSSA();
@@ -439,10 +438,10 @@ public class Compiler {
       new Pass3AddNopBeforeCallOns(program).generate();
       new PassNStatementIndices(program).execute();
       program.clearCallGraph();
-      new PassNStatementInfos(program).execute();
+      program.clearStatementInfos();
       program.clearVariableReferenceInfos();
-      new Pass3LiveRangesAnalysis(program).findLiveRanges();
+      program.clearLiveRangeVariables();
-      new Pass3LiveRangesEffectiveAnalysis(program).findLiveRangesEffective();
+      program.clearLiveRangeVariablesEffective();
       pass2AssertSSA();
 
       getLog().append("\nFINAL CONTROL FLOW GRAPH");
@@ -463,7 +462,7 @@ public class Compiler {
       if(getLog().isVerboseLoopAnalysis()) {
          getLog().append("NATURAL LOOPS");
       }
-      new PassNLoopAnalysis(program).step();
+      program.clearLoopSet();
       if(getLog().isVerboseLoopAnalysis()) {
          getLog().append(program.getLoopSet().toString());
       }
@@ -477,7 +476,7 @@ public class Compiler {
       }
 
       getLog().append("\nVARIABLE REGISTER WEIGHTS");
-      new Pass3VariableRegisterWeightAnalysis(program).findWeights();
+      program.getVariableRegisterWeights();
       getLog().append(program.getScope().toString(program, Variable.class));
 
       new Pass4LiveRangeEquivalenceClassesFinalize(program).allocate();
@@ -502,7 +501,6 @@ public class Compiler {
 
       // Find register uplift scopes
       getLog().append("REGISTER UPLIFT SCOPES");
-      new Pass4RegisterUpliftScopeAnalysis(program).findScopes();
       getLog().append(program.getRegisterUpliftProgram().toString((program.getVariableRegisterWeights())));
 
       // Attempt uplifting registers through a lot of combinations

src/main/java/dk/camelot64/kickc/model/LiveRangeVariables.java

@@ -1,7 +1,7 @@
 package dk.camelot64.kickc.model;
 
 import dk.camelot64.kickc.model.values.VariableRef;
-import dk.camelot64.kickc.passes.Pass3LiveRangesAnalysis;
+import dk.camelot64.kickc.passes.PassNCalcLiveRangeVariables;
 
 import java.util.ArrayList;
 import java.util.LinkedHashMap;
@@ -10,7 +10,7 @@ import java.util.Map;
 
 /**
  * Live ranges for all variables.
- * Created by {@link Pass3LiveRangesAnalysis}
+ * Created by {@link PassNCalcLiveRangeVariables}
  */
 public class LiveRangeVariables {
 

src/main/java/dk/camelot64/kickc/model/LiveRangeVariablesEffective.java

@@ -8,13 +8,14 @@ import dk.camelot64.kickc.model.statements.Statement;
 import dk.camelot64.kickc.model.symbols.Procedure;
 import dk.camelot64.kickc.model.symbols.Scope;
 import dk.camelot64.kickc.passes.Pass2AliasElimination;
+import dk.camelot64.kickc.passes.PassNCalcLiveRangesEffective;
 
 import java.util.*;
 
 /**
  * Effective variable live ranges for all statements.
  * (Including variables alive in calling methods).
- * Created by {@link dk.camelot64.kickc.passes.Pass3LiveRangesEffectiveAnalysis}
+ * Created by {@link PassNCalcLiveRangesEffective}
  */
 public class LiveRangeVariablesEffective {
 

src/main/java/dk/camelot64/kickc/model/NaturalLoopSet.java

@@ -1,14 +1,14 @@
 package dk.camelot64.kickc.model;
 
 import dk.camelot64.kickc.model.values.LabelRef;
-import dk.camelot64.kickc.passes.PassNLoopAnalysis;
+import dk.camelot64.kickc.passes.PassNCalcLoopSet;
 
 import java.util.*;
 
 /**
  * A set of natural loops in a control flow graph.
  * <p>For definitions and more see http://www.cs.colostate.edu/~cs553/ClassNotes/lecture09-control-dominators.ppt.pdf
- * <p>Created by {@link PassNLoopAnalysis}
+ * <p>Created by {@link PassNCalcLoopSet}
  */
 public class NaturalLoopSet {
 

src/main/java/dk/camelot64/kickc/model/Program.java

@@ -51,6 +51,8 @@ public class Program {
    private ProgramScope scope;
    /** The control flow graph. PASS 1-5 (DYNAMIC) */
    private ControlFlowGraph graph;
+   /** Registers potentially usable as allocation for each live range equivalence class. PASS 4 (DYNAMIC) */
+   private RegisterPotentials registerPotentials;
    /** Live range equivalence classes containing variables that do not have overlapping live ranges. PASS 3-5 (DYNAMIC) */
    private LiveRangeEquivalenceClassSet liveRangeEquivalenceClassSet;
    /** The 6502 ASM program. PASS 4-5 (DYNAMIC) */
@@ -67,22 +69,19 @@ public class Program {
    private DominatorsGraph dominators;
    /** Cached information about symbols. Contains a symbol table cache for fast access. PASS 3-4 (CACHED ON-DEMAND) */
    private SymbolInfos symbolInfos;
-   /** Cached phi transitions into each block. PASS 4 (CACHED) */
+   /** Cached phi transitions into each block. PASS 4 (CACHED ON-DEMAND) */
    private Map<LabelRef, PhiTransitions> phiTransitions;
-   /** The live ranges of all variables. PASS 3-4 (CACHED) */
+   /** The live ranges of all variables. PASS 3-4 (CACHED ON-DEMAND) */
    private LiveRangeVariables liveRangeVariables;
-   /** The effective live ranges of all variables. PASS 3-4 (CACHED) */
+   /** The effective live ranges of all variables. PASS 3-4 (CACHED ON-DEMAND) */
    private LiveRangeVariablesEffective liveRangeVariablesEffective;
-   /** Registers potentially usable as allocation for each live range equivalence class. PASS 4 (CACHED) */
+   /** Separation of live range equivalence classes into scopes - used for register uplift. PASS 4 (CACHED ON-DEMAND) */
-   private RegisterPotentials registerPotentials;
-   /** Separation of live range equivalence classes into scopes - used for register uplift. PASS 4 (CACHED) */
    private RegisterUpliftProgram registerUpliftProgram;
-
+   /** Cached information about which block is each statement a part of. PASS 2U-5 (CACHED ON-DEMAND) */
-   /** Cached information about which block is each statement a part of. PASS 2U-5 (CACHED) */
    private StatementInfos statementInfos;
-   /** Information about loops. PASS 2U-5 (CACHED) */
+   /** Information about loops. PASS 2U-5 (CACHED ON-DEMAND) */
    private NaturalLoopSet loopSet;
-   /** The register weight of all variables describing how much the variable would theoretically gain from being in a register. PASS 3-5 (CACHED) */
+   /** The register weight of all variables describing how much the variable would theoretically gain from being in a register. PASS 3-5 (CACHED ON-DEMAND) */
    private VariableRegisterWeights variableRegisterWeights;
 
    public Program() {
@@ -279,22 +278,28 @@ public class Program {
       this.phiTransitions = null;
    }
 
-
+   public LiveRangeVariables getLiveRangeVariables() {
-   public NaturalLoopSet getLoopSet() {
+      if(liveRangeVariables==null)
-      return loopSet;
+         this.liveRangeVariables = new PassNCalcLiveRangeVariables(this).calculate();
+      return liveRangeVariables;
    }
 
-   public void setLoopSet(NaturalLoopSet loopSet) {
+   public void setLiveRangeVariables(LiveRangeVariables liveRangeVariables) {
-      this.loopSet = loopSet;
+      this.liveRangeVariables = liveRangeVariables;
    }
 
+   public void clearLiveRangeVariables() {
+      this.liveRangeVariables = null;
+   }
 
    public StatementInfos getStatementInfos() {
+      if(statementInfos==null)
+         this.statementInfos = new PassNCalcStatementInfos(this).calculate();
       return statementInfos;
    }
 
-   public void setStatementInfos(StatementInfos statementInfos) {
+   public void clearStatementInfos() {
-      this.statementInfos = statementInfos;
+      this.statementInfos = null;
    }
 
    public SymbolInfos getSymbolInfos() {
@@ -303,20 +308,40 @@ public class Program {
       return symbolInfos;
    }
 
-   public LiveRangeVariables getLiveRangeVariables() {
-      return liveRangeVariables;
-   }
-
-   public void setLiveRangeVariables(LiveRangeVariables liveRangeVariables) {
-      this.liveRangeVariables = liveRangeVariables;
-   }
-
    public LiveRangeVariablesEffective getLiveRangeVariablesEffective() {
+      if(liveRangeVariablesEffective==null)
+         this.liveRangeVariablesEffective = new PassNCalcLiveRangesEffective(this).calculate();
       return liveRangeVariablesEffective;
    }
 
-   public void setLiveRangeVariablesEffective(LiveRangeVariablesEffective liveRangeVariablesEffective) {
+   public void clearLiveRangeVariablesEffective() {
-      this.liveRangeVariablesEffective = liveRangeVariablesEffective;
+      this.liveRangeVariablesEffective = null;
+   }
+
+   public RegisterUpliftProgram getRegisterUpliftProgram() {
+      if(registerUpliftProgram==null)
+         this.registerUpliftProgram = new PassNCalcRegisterUpliftProgram(this).calculate();
+      return registerUpliftProgram;
+   }
+
+   public NaturalLoopSet getLoopSet() {
+      if(loopSet==null)
+         this.loopSet = new PassNCalcLoopSet(this).calculate();
+      return loopSet;
+   }
+
+   public void clearLoopSet() {
+      this.loopSet = null;
+   }
+
+   public VariableRegisterWeights getVariableRegisterWeights() {
+      if(variableRegisterWeights==null)
+         this.variableRegisterWeights = new PassNCalcVariableRegisterWeight(this).calculate();
+      return variableRegisterWeights;
+   }
+
+   public VariableRegisterWeights getOrNullVariableRegisterWeights() {
+      return variableRegisterWeights;
    }
 
    public LiveRangeEquivalenceClassSet getLiveRangeEquivalenceClassSet() {
@@ -327,14 +352,6 @@ public class Program {
       this.liveRangeEquivalenceClassSet = liveRangeEquivalenceClassSet;
    }
 
-   public VariableRegisterWeights getVariableRegisterWeights() {
-      return variableRegisterWeights;
-   }
-
-   public void setVariableRegisterWeights(VariableRegisterWeights variableRegisterWeights) {
-      this.variableRegisterWeights = variableRegisterWeights;
-   }
-
    public RegisterPotentials getRegisterPotentials() {
       return registerPotentials;
    }
@@ -343,14 +360,6 @@ public class Program {
       this.registerPotentials = registerPotentials;
    }
 
-   public RegisterUpliftProgram getRegisterUpliftProgram() {
-      return registerUpliftProgram;
-   }
-
-   public void setRegisterUpliftProgram(RegisterUpliftProgram registerUpliftProgram) {
-      this.registerUpliftProgram = registerUpliftProgram;
-   }
-
    public Collection<VariableRef> getEarlyIdentifiedConstants() {
       return earlyIdentifiedConstants;
    }

src/main/java/dk/camelot64/kickc/model/symbols/ProgramScope.java

@@ -28,7 +28,7 @@ public class ProgramScope extends Scope {
       if(liveRangeEquivalenceClassSet != null) {
          out.append("\n");
          for(LiveRangeEquivalenceClass liveRangeEquivalenceClass : liveRangeEquivalenceClassSet.getEquivalenceClasses()) {
-            out.append(liveRangeEquivalenceClass);
+            out.append(liveRangeEquivalenceClass.toString());
             out.append("\n");
          }
       }

src/main/java/dk/camelot64/kickc/model/symbols/Scope.java

@@ -324,7 +324,7 @@ public abstract class Scope implements Symbol {
    }
 
    public String toString(Program program, Class symbolClass) {
-      VariableRegisterWeights registerWeights = program.getVariableRegisterWeights();
+      VariableRegisterWeights registerWeights = program.getOrNullVariableRegisterWeights();
       StringBuilder res = new StringBuilder();
       Set<String> names = symbols.keySet();
       List<String> sortedNames = new ArrayList<>(names);

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

@@ -18,13 +18,14 @@ import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
 
-public class Pass3LiveRangesAnalysis extends Pass2Base {
+public class PassNCalcLiveRangeVariables extends PassNCalcBase<LiveRangeVariables> {
 
-   public Pass3LiveRangesAnalysis(Program program) {
+   public PassNCalcLiveRangeVariables(Program program) {
       super(program);
    }
 
-   public void findLiveRanges() {
+   @Override
+   public LiveRangeVariables calculate() {
       LiveRangeVariables liveRanges = new LiveRangeVariables(getProgram());
       boolean propagating;
       do {
@@ -36,6 +37,7 @@ public class Pass3LiveRangesAnalysis extends Pass2Base {
             getLog().append(getProgram().getGraph().toString(getProgram()));
          }
       } while(propagating);
+      return liveRanges;
    }
 
    /**

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

@@ -1,21 +1,24 @@
 package dk.camelot64.kickc.passes;
 
 import dk.camelot64.kickc.model.*;
-import dk.camelot64.kickc.model.values.*;
 import dk.camelot64.kickc.model.statements.Statement;
 import dk.camelot64.kickc.model.statements.StatementAssignment;
-import dk.camelot64.kickc.model.statements.StatementCall;
 import dk.camelot64.kickc.model.statements.StatementPhiBlock;
 import dk.camelot64.kickc.model.symbols.Procedure;
 import dk.camelot64.kickc.model.symbols.Scope;
 import dk.camelot64.kickc.model.symbols.Variable;
+import dk.camelot64.kickc.model.values.*;
 
 import java.util.*;
 
 /**
  * Find effective alive intervals for all variables in all statements. Add the intervals to the Program.
  */
-public class Pass3LiveRangesEffectiveAnalysis extends Pass2Base {
+public class PassNCalcLiveRangesEffective extends PassNCalcBase<LiveRangeVariablesEffective> {
+
+   public PassNCalcLiveRangesEffective(Program program) {
+      super(program);
+   }
 
    /**
     * Call-paths for all procedures.
@@ -32,18 +35,14 @@ public class Pass3LiveRangesEffectiveAnalysis extends Pass2Base {
     */
    private VariableReferenceInfos referenceInfo;
 
-
+   @Override
-   public Pass3LiveRangesEffectiveAnalysis(Program program) {
+   public LiveRangeVariablesEffective calculate() {
-      super(program);
-   }
-
-   public void findLiveRangesEffective() {
       this.liveRangeVariables = getProgram().getLiveRangeVariables();
       this.referenceInfo = getProgram().getVariableReferenceInfos();
       this.procedureCallPaths = new LinkedHashMap<>();
       populateProcedureCallPaths();
       LiveRangeVariablesEffective aliveEffective = new LiveRangeVariablesEffective(getProgram(), procedureCallPaths, liveRangeVariables, referenceInfo);
-      getProgram().setLiveRangeVariablesEffective(aliveEffective);
+      return aliveEffective;
       //getLog().append("Calculated effective variable live ranges");
    }
 

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

@@ -11,13 +11,12 @@ import java.util.*;
  * <p>
  * See http://www.cs.colostate.edu/~cs553/ClassNotes/lecture09-control-dominators.ppt.pdf
  */
-public class PassNLoopAnalysis extends Pass2SsaOptimization {
+public class PassNCalcLoopSet extends PassNCalcBase<NaturalLoopSet> {
 
-   public PassNLoopAnalysis(Program program) {
+   public PassNCalcLoopSet(Program program) {
       super(program);
    }
 
-
    /**
     * Finds loops and nested loops in the control flow graph.
     * Uses the dominators of the graph to find loops.
@@ -25,7 +24,7 @@ public class PassNLoopAnalysis extends Pass2SsaOptimization {
     * See http://www.cs.colostate.edu/~cs553/ClassNotes/lecture09-control-dominators.ppt.pdf
     */
    @Override
-   public boolean step() {
+   public NaturalLoopSet calculate() {
       DominatorsGraph dominators = getProgram().getDominators();
       Collection<ControlFlowBlock> blocks = getGraph().getAllBlocks();
 
@@ -74,8 +73,7 @@ public class PassNLoopAnalysis extends Pass2SsaOptimization {
       while(coalesceMore) {
          coalesceMore = coalesceLoops(loopSet);
       }
-      getProgram().setLoopSet(loopSet);
+      return loopSet;
-      return false;
    }
 
    /**

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

@@ -1,9 +1,9 @@
 package dk.camelot64.kickc.passes;
 
 import dk.camelot64.kickc.model.*;
+import dk.camelot64.kickc.model.symbols.Scope;
 import dk.camelot64.kickc.model.values.ScopeRef;
 import dk.camelot64.kickc.model.values.VariableRef;
-import dk.camelot64.kickc.model.symbols.Scope;
 
 import java.util.ArrayList;
 import java.util.Collection;
@@ -11,26 +11,25 @@ import java.util.Collections;
 import java.util.List;
 
 /*** Find the variable equivalence classes to attempt to uplift in each scope */
-public class Pass4RegisterUpliftScopeAnalysis extends Pass2Base {
+public class PassNCalcRegisterUpliftProgram extends PassNCalcBase<RegisterUpliftProgram> {
 
-   public Pass4RegisterUpliftScopeAnalysis(Program program) {
+   public PassNCalcRegisterUpliftProgram(Program program) {
       super(program);
    }
 
-   /*** Find the variable equivalence classes to attempt to uplift in each scope */
-   public void findScopes() {
 
+   /*** Find the variable equivalence classes to attempt to uplift in each scope */
+   @Override
+   public RegisterUpliftProgram calculate() {
       LiveRangeEquivalenceClassSet equivalenceClassSet = getProgram().getLiveRangeEquivalenceClassSet();
       final VariableRegisterWeights registerWeights = getProgram().getVariableRegisterWeights();
 
       RegisterUpliftProgram registerUpliftProgram = new RegisterUpliftProgram();
-
       Collection<Scope> allScopes = getProgram().getScope().getAllScopes(true);
-      allScopes.add(getSymbols());
+      allScopes.add(getScope());
       for(Scope scope : allScopes) {
          ScopeRef scopeRef = scope.getRef();
          RegisterUpliftScope registerUpliftScope = registerUpliftProgram.addRegisterUpliftScope(scopeRef);
-
          // Find live range equivalence classes for the scope
          List<LiveRangeEquivalenceClass> equivalenceClasses = new ArrayList<>();
          for(LiveRangeEquivalenceClass equivalenceClass : equivalenceClassSet.getEquivalenceClasses()) {
@@ -43,12 +42,11 @@ public class Pass4RegisterUpliftScopeAnalysis extends Pass2Base {
          registerUpliftScope.setEquivalenceClasses(equivalenceClasses);
       }
 
-
       List<RegisterUpliftScope> upliftScopes = registerUpliftProgram.getRegisterUpliftScopes();
       Collections.sort(upliftScopes, (o1, o2) -> Double.compare(registerWeights.getTotalWeights(o2), registerWeights.getTotalWeights(o1)));
       registerUpliftProgram.setRegisterUpliftScopes(upliftScopes);
 
-      getProgram().setRegisterUpliftProgram(registerUpliftProgram);
+      return registerUpliftProgram;
    }
 
 

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

@@ -11,9 +11,9 @@ import java.util.LinkedHashMap;
 /**
  * Identify the block for each statement.
  */
-public class PassNStatementInfos extends Pass2SsaOptimization {
+public class PassNCalcStatementInfos extends PassNCalcBase<StatementInfos> {
 
-   public PassNStatementInfos(Program program) {
+   public PassNCalcStatementInfos(Program program) {
       super(program);
    }
 
@@ -22,7 +22,7 @@ public class PassNStatementInfos extends Pass2SsaOptimization {
     * Create map from statement index to block
     */
    @Override
-   public boolean step() {
+   public StatementInfos calculate() {
       LinkedHashMap<Integer, ControlFlowBlock> stmtBlocks = new LinkedHashMap<>();
       LinkedHashMap<Integer, Statement> stmtIdx = new LinkedHashMap<>();
       for(ControlFlowBlock block : getProgram().getGraph().getAllBlocks()) {
@@ -31,8 +31,7 @@ public class PassNStatementInfos extends Pass2SsaOptimization {
             stmtIdx.put(statement.getIndex(), statement);
          }
       }
-      getProgram().setStatementInfos(new StatementInfos(getProgram(), stmtBlocks, stmtIdx));
+      return new StatementInfos(getProgram(), stmtBlocks, stmtIdx);
-      return false;
    }
 
 

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

@@ -1,12 +1,11 @@
 package dk.camelot64.kickc.passes;
 
 import dk.camelot64.kickc.model.*;
-import dk.camelot64.kickc.model.values.*;
 import dk.camelot64.kickc.model.statements.Statement;
 import dk.camelot64.kickc.model.statements.StatementAssignment;
 import dk.camelot64.kickc.model.statements.StatementConditionalJump;
 import dk.camelot64.kickc.model.statements.StatementPhiBlock;
-import dk.camelot64.kickc.model.symbols.Variable;
+import dk.camelot64.kickc.model.values.*;
 
 /**
  * Finds register weights for all variables.
@@ -17,24 +16,20 @@ import dk.camelot64.kickc.model.symbols.Variable;
  * <p>
  * Based on ComputeWeight from http://compilers.cs.ucla.edu/fernando/projects/soc/reports/short_tech.pdf
  */
-public class Pass3VariableRegisterWeightAnalysis extends Pass2Base {
+public class PassNCalcVariableRegisterWeight extends PassNCalcBase<VariableRegisterWeights> {
 
-   private NaturalLoopSet loopSet;
+   public PassNCalcVariableRegisterWeight(Program program) {
-   private VariableRegisterWeights variableRegisterWeights;
-   private LiveRangeVariables liveRangeVariables;
-
-   public Pass3VariableRegisterWeightAnalysis(Program program) {
       super(program);
    }
 
    /**
     * Find register weights for all variables
     */
-   public void findWeights() {
+   @Override
-
+   public VariableRegisterWeights calculate() {
-      variableRegisterWeights = new VariableRegisterWeights();
+      NaturalLoopSet loopSet = getProgram().getLoopSet();
-      loopSet = getProgram().getLoopSet();
+      LiveRangeVariables liveRangeVariables = getProgram().getLiveRangeVariables();
-      liveRangeVariables = getProgram().getLiveRangeVariables();
+      VariableRegisterWeights variableRegisterWeights = new VariableRegisterWeights();
 
       for(ControlFlowBlock block : getProgram().getGraph().getAllBlocks()) {
          for(Statement statement : block.getStatements()) {
@@ -44,47 +39,44 @@ public class Pass3VariableRegisterWeightAnalysis extends Pass2Base {
                   VariableRef philVariable = phiVariable.getVariable();
                   for(StatementPhiBlock.PhiRValue phiRValue : phiVariable.getValues()) {
                      if(phiRValue.getrValue() instanceof VariableRef) {
-                        double w = addWeight(philVariable, phiRValue.getPredecessor());
+                        double w = addWeight(philVariable, phiRValue.getPredecessor(), variableRegisterWeights, loopSet, liveRangeVariables);
                         //log.append("Definition of " + philVariable + " w+:" + w + " - [" + statement.getIndex()+"]");
                      }
                   }
                   // Add weights for each usage of a variable
                   for(StatementPhiBlock.PhiRValue phiRValue : phiVariable.getValues()) {
-                     addUsageWeightRValue(phiRValue.getrValue(), statement, phiRValue.getPredecessor());
+                     addUsageWeightRValue(phiRValue.getrValue(), statement, phiRValue.getPredecessor(), variableRegisterWeights, loopSet, liveRangeVariables);
                   }
                }
             } else if(statement instanceof StatementAssignment) {
                // Add weights for the definition of the variable
-               addUsageWeightRValue(((StatementAssignment) statement).getlValue(), statement, block.getLabel());
+               addUsageWeightRValue(((StatementAssignment) statement).getlValue(), statement, block.getLabel(), variableRegisterWeights, loopSet, liveRangeVariables);
                // Add weights for each usage of variables
-               addUsageWeightRValue(((StatementAssignment) statement).getrValue1(), statement, block.getLabel());
+               addUsageWeightRValue(((StatementAssignment) statement).getrValue1(), statement, block.getLabel(), variableRegisterWeights, loopSet, liveRangeVariables);
-               addUsageWeightRValue(((StatementAssignment) statement).getrValue2(), statement, block.getLabel());
+               addUsageWeightRValue(((StatementAssignment) statement).getrValue2(), statement, block.getLabel(), variableRegisterWeights, loopSet, liveRangeVariables);
             } else if(statement instanceof StatementConditionalJump) {
                // Add weights for each usage of variables
-               addUsageWeightRValue(((StatementConditionalJump) statement).getrValue1(), statement, block.getLabel());
+               addUsageWeightRValue(((StatementConditionalJump) statement).getrValue1(), statement, block.getLabel(), variableRegisterWeights, loopSet, liveRangeVariables);
-               addUsageWeightRValue(((StatementConditionalJump) statement).getrValue2(), statement, block.getLabel());
+               addUsageWeightRValue(((StatementConditionalJump) statement).getrValue2(), statement, block.getLabel(), variableRegisterWeights, loopSet, liveRangeVariables);
             }
          }
       }
-
+      return variableRegisterWeights;
-      getProgram().setVariableRegisterWeights(variableRegisterWeights);
-
    }
 
-   private void addUsageWeightRValue(Value rValue, Statement statement, LabelRef block) {
+   private static void addUsageWeightRValue(Value rValue, Statement statement, LabelRef block, VariableRegisterWeights variableRegisterWeights, NaturalLoopSet loopSet, LiveRangeVariables liveRangeVariables) {
       if(rValue instanceof VariableRef) {
-         double w = addWeight((VariableRef) rValue, block);
+         double w = addWeight((VariableRef) rValue, block, variableRegisterWeights, loopSet, liveRangeVariables);
          //log.append("Usage of " + rValue + " w+:" + w + " - [" + statement.getIndex()+"]");
       } else if(rValue instanceof PointerDereferenceSimple) {
-         addUsageWeightRValue(((PointerDereferenceSimple) rValue).getPointer(), statement, block);
+         addUsageWeightRValue(((PointerDereferenceSimple) rValue).getPointer(), statement, block, variableRegisterWeights, loopSet, liveRangeVariables);
       } else if(rValue instanceof PointerDereferenceIndexed) {
-         addUsageWeightRValue(((PointerDereferenceIndexed) rValue).getPointer(), statement, block);
+         addUsageWeightRValue(((PointerDereferenceIndexed) rValue).getPointer(), statement, block, variableRegisterWeights, loopSet, liveRangeVariables);
-         addUsageWeightRValue(((PointerDereferenceIndexed) rValue).getIndex(), statement, block);
+         addUsageWeightRValue(((PointerDereferenceIndexed) rValue).getIndex(), statement, block, variableRegisterWeights, loopSet, liveRangeVariables);
       }
    }
 
-   private double addWeight(VariableRef variable, LabelRef block) {
+   private static double addWeight(VariableRef variable, LabelRef block, VariableRegisterWeights variableRegisterWeights, NaturalLoopSet loopSet, LiveRangeVariables liveRangeVariables) {
-      Variable var = getProgram().getScope().getVariable(variable);
       int depth = loopSet.getMaxLoopDepth(block);
       double w = 1.0 + Math.pow(10.0, depth);
       LiveRange liveRange = liveRangeVariables.getLiveRange(variable);