kickc/src/main/java/dk/camelot64/kickc/passes/Pass1UnwindStructPrepare.java

package dk.camelot64.kickc.passes;

import dk.camelot64.kickc.model.Initializers;
import dk.camelot64.kickc.model.Program;
import dk.camelot64.kickc.model.statements.StatementAssignment;
import dk.camelot64.kickc.model.statements.StatementCall;
import dk.camelot64.kickc.model.symbols.Procedure;
import dk.camelot64.kickc.model.symbols.Variable;
import dk.camelot64.kickc.model.types.SymbolType;
import dk.camelot64.kickc.model.types.SymbolTypeInference;
import dk.camelot64.kickc.model.types.SymbolTypeStruct;
import dk.camelot64.kickc.model.values.CastValue;
import dk.camelot64.kickc.model.values.ConstantValue;
import dk.camelot64.kickc.model.values.RValue;
import dk.camelot64.kickc.model.values.ValueList;
import java.util.List;

/**
 * Prepare structs for unwinding.
 * - Constantify all assignment RValues that are structs
 * - Add casts to struct parameter values in calls
 */
public class Pass1UnwindStructPrepare extends Pass2SsaOptimization {

   public Pass1UnwindStructPrepare(Program program) {
      super(program);
   }

   @Override
   public boolean step() {
      for(var statement : getGraph().getAllStatements()) {
         if(statement instanceof StatementAssignment assignment) {
            if(assignment.getOperator()==null) {
               SymbolType lValueType = SymbolTypeInference.inferType(getProgram().getScope(), assignment.getlValue());
               RValue rValue = assignment.getrValue2();
               if(!(rValue instanceof ConstantValue) && lValueType instanceof SymbolTypeStruct) {
                  // TODO: Constantify all R-Values?
                  Initializers.ValueTypeSpec lValueTypeSpec = new Initializers.ValueTypeSpec(lValueType);
                  RValue rValueConstantified = Initializers.constantify(rValue, lValueTypeSpec, getProgram(), assignment.getSource());
                  if(!rValue.equals(rValueConstantified)) {
                     assignment.setrValue2(rValueConstantified);
                     getLog().append("Constantified RValue "+assignment.toString(getProgram(), false));
                  }
               }

            }
         }
         if(statement instanceof final StatementCall call) {
            final Procedure procedure = getProgramScope().getProcedure(call.getProcedure());
            final List<Variable> paramDefs = procedure.getParameters();
            final List<RValue> paramVals = call.getParameters();
            for(int i=0;i<paramDefs.size();i++) {
               final Variable paramDef = paramDefs.get(i);
               final RValue paramVal = paramVals.get(i);
               if(paramDef.getType() instanceof SymbolTypeStruct && paramVal instanceof ValueList) {
                  // Add a cast to the parameter value list
                  paramVals.set(i, new CastValue(paramDef.getType(), paramVal));
                  getLog().append("Added struct type cast to parameter value list "+call.toString(getProgram(), false));
               }
            }
         }
      }
      return false;
   }


}