LoopingConditionFactory.java

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package jdk.test.lib.jittester.factories;

import jdk.test.lib.jittester.BinaryOperator;
import jdk.test.lib.jittester.IRNode;
import jdk.test.lib.jittester.Literal;
import jdk.test.lib.jittester.LocalVariable;
import jdk.test.lib.jittester.OperatorKind;
import jdk.test.lib.jittester.ProductionFailedException;
import jdk.test.lib.jittester.TypeList;
import jdk.test.lib.jittester.loops.LoopingCondition;
import jdk.test.lib.jittester.types.TypeKlass;
import jdk.test.lib.jittester.utils.PseudoRandom;

class LoopingConditionFactory extends Factory<LoopingCondition> {
    private final LocalVariable counter;
    private final Literal limiter;
    private final int operatorLimit;
    private final long complexityLimit;
    private final TypeKlass ownerClass;

    LoopingConditionFactory(long complexityLimit, int operatorLimit, TypeKlass ownerClass,
            LocalVariable counter, Literal limiter) {
        this.complexityLimit = complexityLimit;
        this.operatorLimit = operatorLimit;
        this.counter = counter;
        this.limiter = limiter;
        this.ownerClass = ownerClass;
    }

    @Override
    public LoopingCondition produce() throws ProductionFailedException {
        IRNode leftExpression = null;
        IRNode rightExpression = null;
        Factory<IRNode> exprFactory = new IRNodeBuilder()
                .setResultType(TypeList.BOOLEAN)
                .setComplexityLimit((complexityLimit - 1) / 2)
                .setOperatorLimit((operatorLimit - 1) / 2)
                .setOwnerKlass(ownerClass)
                .setExceptionSafe(false)
                .setNoConsts(false)
                .getLimitedExpressionFactory();
        if (PseudoRandom.randomBoolean()) {
            leftExpression = exprFactory.produce();
        }
        if (PseudoRandom.randomBoolean()) {
            rightExpression = exprFactory.produce();
        }
        // Depending on loop counter direction, we should synthesize limiting condition.
        // Example: If the counter is counting forward. Then the looping condition can be:
        // counter < n, counter <= n, n > counter, n >= counter, n - counter > 0, etc..

        // Just as a temporary solution we'll assume that the counter is monotonically increasing.
        // And use counter < n condition to limit the loop.
        // In future we may introduce other equivalent relations as well.
        BinaryOperator condition = new BinaryOperator(OperatorKind.LT, TypeList.BOOLEAN, counter, limiter);
        condition = (rightExpression != null) ? new BinaryOperator(OperatorKind.AND, TypeList.BOOLEAN, condition,
                rightExpression) : condition;
        condition = (leftExpression != null) ? new BinaryOperator(OperatorKind.AND, TypeList.BOOLEAN, leftExpression,
                condition) : condition;
        return new LoopingCondition(condition);
    }
}