Implemented usage counting in sub-constant elimination. Added some more fragments

src/dk/camelot64/kickc/asm/fragment/aby=zpby1_plus_coby1.asm

@@ -0,0 +1,3 @@
+lda {zpby1}
+clc
+adc #{coby1}

src/dk/camelot64/kickc/asm/fragment/aby=zpby1_plus_zpby2.asm

@@ -0,0 +1,3 @@
+lda {zpby1}
+clc
+adc {zpby2}

src/dk/camelot64/kickc/asm/fragment/zpby1=aby.asm

@@ -0,0 +1 @@
+sta {zpby1}

src/dk/camelot64/kickc/asm/fragment/zpby1=aby_plus_coby1.asm

@@ -0,0 +1,3 @@
+clc
+adc #{coby1}
+sta {zpby1}

src/dk/camelot64/kickc/icl/ControlFlowGraphBaseVisitor.java

@@ -32,7 +32,7 @@ public class ControlFlowGraphBaseVisitor<T> {
       } else if(statement instanceof StatementPhi) {
          return visitPhi((StatementPhi) statement);
       } else if(statement instanceof StatementCall) {
-         return visitCallLValue((StatementCall) statement);
+         return visitCall((StatementCall) statement);
       } else if(statement instanceof StatementReturn) {
          return visitReturn((StatementReturn) statement);
       } else if(statement instanceof StatementProcedureBegin) {
@@ -76,7 +76,7 @@ public class ControlFlowGraphBaseVisitor<T> {
       return null;
    }
 
-   public T visitCallLValue(StatementCall callLValue) {
+   public T visitCall(StatementCall callLValue) {
       return null;
    }
 

src/dk/camelot64/kickc/icl/ControlFlowGraphCopyVisitor.java

@@ -156,7 +156,7 @@ public class ControlFlowGraphCopyVisitor extends ControlFlowGraphBaseVisitor<Obj
    }
 
    @Override
-   public StatementCall visitCallLValue(StatementCall callLValue) {
+   public StatementCall visitCall(StatementCall callLValue) {
       LValue lValue = callLValue.getLValue();
       String procedureName = callLValue.getProcedureName();
       List<RValue> parameters = callLValue.getParameters();

src/dk/camelot64/kickc/icl/Pass1ProcedureCallParameters.java

@@ -19,7 +19,7 @@ public class Pass1ProcedureCallParameters extends ControlFlowGraphCopyVisitor {
    }
 
    @Override
-   public StatementCall visitCallLValue(StatementCall origCall) {
+   public StatementCall visitCall(StatementCall origCall) {
       // Procedure strategy implemented is currently variable-based transfer of parameters/return values
       // Generate parameter passing assignments
       Procedure procedure = origCall.getProcedure();

src/dk/camelot64/kickc/icl/Pass1ProcedureCallsReturnValue.java

@@ -17,7 +17,7 @@ public class Pass1ProcedureCallsReturnValue extends ControlFlowGraphCopyVisitor
    }
 
    @Override
-   public StatementCall visitCallLValue(StatementCall origCall) {
+   public StatementCall visitCall(StatementCall origCall) {
       // Procedure strategy implemented is currently variable-based transfer of parameters/return values
       // Generate return value assignment
       Procedure procedure = origCall.getProcedure();

src/dk/camelot64/kickc/icl/Pass2ConstantAdditionElimination.java

@@ -1,5 +1,8 @@
 package dk.camelot64.kickc.icl;
 
+import java.util.HashMap;
+import java.util.Map;
+
 /**
  * Compiler Pass eliminating several additions of constants by consolidating them to a single (compile time) constant c1+v+c2 => (c1+c2)+v
  *
@@ -12,6 +15,8 @@ package dk.camelot64.kickc.icl;
  */
 public class Pass2ConstantAdditionElimination extends Pass2SsaOptimization {
 
+   private Map<Variable, Integer> usages;
+
    public Pass2ConstantAdditionElimination(ControlFlowGraph graph, Scope scope) {
       super(graph, scope);
    }
@@ -24,6 +29,9 @@ public class Pass2ConstantAdditionElimination extends Pass2SsaOptimization {
    @Override
    public boolean optimize() {
       boolean optimized = false;
+
+      this.usages = countVarUsages();
+
       // Examine all assigments - performing constant consolidation
       for (ControlFlowBlock block : getGraph().getAllBlocks()) {
          for (Statement statement : block.getStatements()) {
@@ -116,6 +124,10 @@ public class Pass2ConstantAdditionElimination extends Pass2SsaOptimization {
     * @return The consolidated constant. Null if no sub-constants were found.
     */
    private ConstantInteger consolidateSubConstants(Variable variable) {
+      if(usages.get(variable)>1) {
+         System.out.println("Multiple usages for variable. Not optimizing sub-constant "+variable);
+         return null;
+      }
       StatementAssignment assignment = getGraph().getAssignment(variable);
       if (assignment != null && assignment.getOperator() != null && "+".equals(assignment.getOperator().getOperator())) {
          if (assignment.getRValue1() instanceof ConstantInteger) {

src/dk/camelot64/kickc/icl/Pass2SsaOptimization.java

@@ -110,7 +110,7 @@ public abstract class Pass2SsaOptimization {
          }
 
          @Override
-         public Void visitCallLValue(StatementCall call) {
+         public Void visitCall(StatementCall call) {
             if(call.getParameters()!=null) {
                List<RValue> newParams = new ArrayList<>();
                for (RValue parameter : call.getParameters()) {
@@ -309,4 +309,57 @@ public abstract class Pass2SsaOptimization {
 
       return usages;
    }
+
+   protected Map<Variable, Integer> countVarUsages() {
+      final HashMap<Variable, Integer> usages = new HashMap<>();
+      ControlFlowGraphBaseVisitor usageVisitor = new ControlFlowGraphBaseVisitor() {
+         private void addUsage(RValue rVal) {
+            if(rVal instanceof Variable) {
+               Variable var = (Variable) rVal;
+               Integer usage = usages.get(var);
+               if (usage == null) {
+                  usage = 0;
+               }
+               usage = usage + 1;
+               usages.put(var, usage);
+            } else if(rVal instanceof PointerDereference) {
+               throw new RuntimeException("Unexpected pointer dereference!");
+            }
+         }
+
+
+         @Override
+         public Object visitAssignment(StatementAssignment assignment) {
+            addUsage(assignment.getRValue1());
+            addUsage(assignment.getRValue2());
+            return null;
+         }
+
+         @Override
+         public Object visitReturn(StatementReturn aReturn) {
+            addUsage(aReturn.getValue());
+            return null;
+         }
+
+         @Override
+         public Object visitCall(StatementCall call) {
+            if(call.getParameters()!=null) {
+               for (RValue param : call.getParameters()) {
+                  addUsage(param);
+               }
+            }
+            return null;
+         }
+
+         @Override
+         public Object visitPhi(StatementPhi phi) {
+            for (StatementPhi.PreviousSymbol previousSymbol : phi.getPreviousVersions()) {
+               addUsage(previousSymbol.getRValue());
+            }
+            return null;
+         }
+      };
+      usageVisitor.visitGraph(getGraph());
+      return usages;
+   }
 }

src/dk/camelot64/kickc/icl/Pass3RegisterAllocation.java

@@ -53,13 +53,16 @@ public class Pass3RegisterAllocation {
       //allocation.allocate(symbols.getVariable("$0"), new RegisterAllocation.RegisterAByte());
       //allocation.allocate(symbols.getVariable("$2"), new RegisterAllocation.RegisterAByte());
       //allocation.allocate(symbols.getVariable("$3"), new RegisterAllocation.RegisterAByte());
-      allocation.allocate(symbols.getVariable("$1"), new RegisterAllocation.RegisterAByte());
+      //allocation.allocate(symbols.getVariable("$1"), new RegisterAllocation.RegisterAByte());
-      allocation.allocate(symbols.getVariable("$3"), new RegisterAllocation.RegisterALUByte());
+      //allocation.allocate(symbols.getVariable("$3"), new RegisterAllocation.RegisterALUByte());
-      allocation.allocate(symbols.getVariable("$4"), new RegisterAllocation.RegisterAByte());
+      //allocation.allocate(symbols.getVariable("$4"), new RegisterAllocation.RegisterAByte());
-      allocation.allocate(symbols.getVariable("$6"), new RegisterAllocation.RegisterALUByte());
+      //allocation.allocate(symbols.getVariable("$6"), new RegisterAllocation.RegisterALUByte());
-      allocation.allocate(symbols.getVariable("$7"), new RegisterAllocation.RegisterAByte());
+      //allocation.allocate(symbols.getVariable("$7"), new RegisterAllocation.RegisterAByte());
       //allocation.allocate(symbols.getVariable("inc::a#2"), new RegisterAllocation.RegisterAByte());
       //allocation.allocate(symbols.getVariable("bv#0"), new RegisterAllocation.RegisterAByte());
+      allocation.allocate(symbols.getVariable("sum::b#0"), new RegisterAllocation.RegisterAByte());
+      allocation.allocate(symbols.getVariable("inc::b#1"), new RegisterAllocation.RegisterAByte());
+      allocation.allocate(symbols.getVariable("a#0"), new RegisterAllocation.RegisterAByte());
       symbols.setAllocation(allocation);
 
    }

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

@@ -64,7 +64,7 @@ public class Main {
       List<Pass2SsaOptimization> optimizations = new ArrayList<>();
       optimizations.add(new Pass2CullEmptyBlocks(controlFlowGraph, programScope));
       optimizations.add(new Pass2ConstantPropagation(controlFlowGraph, programScope));
-      //optimizations.add(new Pass2ConstantAdditionElimination(controlFlowGraph, programScope));
+      optimizations.add(new Pass2ConstantAdditionElimination(controlFlowGraph, programScope));
       optimizations.add(new Pass2AliasElimination(controlFlowGraph, programScope));
       optimizations.add(new Pass2RedundantPhiElimination(controlFlowGraph, programScope));
       optimizations.add(new Pass2SelfPhiElimination(controlFlowGraph, programScope));

src/dk/camelot64/kickc/test/callsum.kc

@@ -1,6 +1,6 @@
 byte a = 12;
 byte s = sum(5,a);
-a = a+s;
+a = a+s+4;
 a = sum(s, a);
 
 byte sum(byte b1, byte b2) {