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 * 1. Redistributions of source code must retain the above copyright notice, this list of
 * conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other materials provided
 * with the distribution.
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 * 3. Neither the name of the copyright holder nor the names of its contributors may be used to
 * endorse or promote products derived from this software without specific prior written
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package com.oracle.truffle.llvm.nodes.control;

import com.oracle.truffle.api.CompilerAsserts;
import com.oracle.truffle.api.frame.VirtualFrame;
import com.oracle.truffle.api.nodes.ExplodeLoop;
import com.oracle.truffle.api.source.SourceSection;
import com.oracle.truffle.llvm.runtime.nodes.api.LLVMControlFlowNode;
import com.oracle.truffle.llvm.runtime.nodes.api.LLVMExpressionNode;

public class LLVMConditionalBranchNode extends LLVMControlFlowNode {

    @Child private LLVMExpressionNode condition;
    @Children final LLVMExpressionNode[] truePhiWriteNodes;
    @Children final LLVMExpressionNode[] falsePhiWriteNodes;
    private final int trueSuccessor;
    private final int falseSuccessor;

    public static final int TRUE_SUCCESSOR = 0;
    public static final int FALSE_SUCCESSOR = 1;

    public LLVMConditionalBranchNode(int trueSuccessor, int falseSuccessor, LLVMExpressionNode[] truePhiWriteNodes, LLVMExpressionNode[] falsePhiWriteNodes, LLVMExpressionNode condition,
                    SourceSection sourceSection) {
        super(sourceSection);
        this.trueSuccessor = trueSuccessor;
        this.falseSuccessor = falseSuccessor;
        this.truePhiWriteNodes = truePhiWriteNodes;
        this.falsePhiWriteNodes = falsePhiWriteNodes;
        this.condition = condition;
    }

    @Override
    public int getSuccessorCount() {
        return 2;
    }

    public void writePhis(VirtualFrame frame, int successorIndex) {
        CompilerAsserts.partialEvaluationConstant(successorIndex);
        if (successorIndex == TRUE_SUCCESSOR) {
            runTruePhis(frame);
        } else {
            assert successorIndex == FALSE_SUCCESSOR;
            runFalsePhis(frame);
        }
    }

    @ExplodeLoop
    private void runFalsePhis(VirtualFrame frame) {
        for (int i = 0; i < falsePhiWriteNodes.length; i++) {
            falsePhiWriteNodes[i].executeGeneric(frame);
        }
    }

    @ExplodeLoop
    private void runTruePhis(VirtualFrame frame) {
        for (int i = 0; i < truePhiWriteNodes.length; i++) {
            truePhiWriteNodes[i].executeGeneric(frame);
        }
    }

    public boolean executeCondition(VirtualFrame frame) {
        return condition.executeI1(frame);
    }

    public int getTrueSuccessor() {
        return trueSuccessor;
    }

    public int getFalseSuccessor() {
        return falseSuccessor;
    }
}