Method buildUnboundedLoop

src/strands/strands_for.js:178–305

(cfg, branchBlock, mergeBlock, initialVar, phiNode, conditionNode, updateResult)

  }

  buildUnboundedLoop(cfg, branchBlock, mergeBlock, initialVar, phiNode, conditionNode, updateResult) {
    // For unbounded loops, create FOR block with infinite loop and break condition
    const forBlock = CFG.createBasicBlock(cfg, BlockType.FOR);
    CFG.addEdge(cfg, branchBlock, forBlock);

    // Create FOR block with three empty statements for for(;;) syntax
    CFG.pushBlock(cfg, forBlock);

    // 1. Init statement - initialize loop variable or empty
    if (initialVar) {
      const initAssignmentNode = DAG.createNodeData({
        nodeType: NodeType.ASSIGNMENT,
        dependsOn: [phiNode.id, initialVar.id],
        phiBlocks: []
      });
      const initAssignmentID = DAG.getOrCreateNode(this.strandsContext.dag, initAssignmentNode);
      CFG.recordInBasicBlock(cfg, forBlock, initAssignmentID);
    } else {
      // Create empty statement for init
      const emptyInitNode = DAG.createNodeData({
        nodeType: NodeType.STATEMENT,
        statementType: StatementType.EMPTY,
        dependsOn: [],
        phiBlocks: []
      });
      const emptyInitID = DAG.getOrCreateNode(this.strandsContext.dag, emptyInitNode);
      CFG.recordInBasicBlock(cfg, forBlock, emptyInitID);
    }

    // 2. Condition statement - empty for infinite loop
    const emptyConditionNode = DAG.createNodeData({
      nodeType: NodeType.STATEMENT,
      statementType: StatementType.EMPTY,
      dependsOn: [],
      phiBlocks: []
    });
    const emptyConditionID = DAG.getOrCreateNode(this.strandsContext.dag, emptyConditionNode);
    CFG.recordInBasicBlock(cfg, forBlock, emptyConditionID);

    // 3. Update statement - empty for infinite loop
    const emptyUpdateNode = DAG.createNodeData({
      nodeType: NodeType.STATEMENT,
      statementType: StatementType.EMPTY,
      dependsOn: [],
      phiBlocks: []
    });
    const emptyUpdateID = DAG.getOrCreateNode(this.strandsContext.dag, emptyUpdateNode);
    CFG.recordInBasicBlock(cfg, forBlock, emptyUpdateID);

    CFG.popBlock(cfg);

    const scopeStartBlock = CFG.createBasicBlock(cfg, BlockType.SCOPE_START);
    CFG.addEdge(cfg, forBlock, scopeStartBlock);

    // Add break condition check right after scope start
    const breakCheckBlock = CFG.createBasicBlock(cfg, BlockType.DEFAULT);
    CFG.addEdge(cfg, scopeStartBlock, breakCheckBlock);