import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
@Override
public <T extends LexicalContextNode> T pop(final T node) {
    final T popped = super.pop(node);
    if (isWithBoundary(node)) {
        dynamicScopeCount--;
        assert dynamicScopeCount >= 0;
    } else if (node instanceof FunctionNode) {
        if (((FunctionNode)node).inDynamicContext()) {
            dynamicScopeCount--;
            assert dynamicScopeCount >= 0;
        }
        assert splitNodes.peek() == 0;
        splitNodes.pop();
    }
    return popped;
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
private Map<Symbol, LvarType> getBreakTargetTypes(final BreakableNode target) {
    // Remove symbols defined in the the blocks that are being broken out of.
    Map<Symbol, LvarType> types = localVariableTypes;
    for(final Iterator<LexicalContextNode> it = lc.getAllNodes(); it.hasNext();) {
        final LexicalContextNode node = it.next();
        if(node instanceof Block) {
            for(final Symbol symbol: ((Block)node).getSymbols()) {
                if(localVariableTypes.containsKey(symbol)) {
                    if(types == localVariableTypes) {
                        types = cloneMap(localVariableTypes);
                    }
                    types.remove(symbol);
                }
            }
        }
        if(node == target) {
            break;
        }
    }
    return types;
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
private Map<Symbol, LvarType> getBreakTargetTypes(final LexicalContextNode target) {
    // Remove symbols defined in the the blocks that are being broken out of.
    Map<Symbol, LvarType> types = localVariableTypes;
    for(final Iterator<LexicalContextNode> it = lc.getAllNodes(); it.hasNext();) {
        final LexicalContextNode node = it.next();
        if(node instanceof Block) {
            for(final Symbol symbol: ((Block)node).getSymbols()) {
                if(localVariableTypes.containsKey(symbol)) {
                    if(types == localVariableTypes) {
                        types = cloneMap(localVariableTypes);
                    }
                    types.remove(symbol);
                }
            }
        }
        if(node == target) {
            break;
        }
    }
    return types;
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
/**
 * Determines if the symbol has to be a scope symbol. In general terms, it has to be a scope symbol if it can only
 * be reached from the current block by traversing a function node, a split node, or a with node.
 * @param symbol the symbol checked for needing to be a scope symbol
 * @return true if the symbol has to be a scope symbol.
 */
private boolean symbolNeedsToBeScope(final Symbol symbol) {
    if (symbol.isThis() || symbol.isInternal()) {
        return false;
    }

    final FunctionNode func = lc.getCurrentFunction();
    if ( func.allVarsInScope() || (!symbol.isBlockScoped() && func.isProgram())) {
        return true;
    }

    boolean previousWasBlock = false;
    for (final Iterator<LexicalContextNode> it = lc.getAllNodes(); it.hasNext();) {
        final LexicalContextNode node = it.next();
        if (node instanceof FunctionNode || isSplitArray(node)) {
            // We reached the function boundary or a splitting boundary without seeing a definition for the symbol.
            // It needs to be in scope.
            return true;
        } else if (node instanceof WithNode) {
            if (previousWasBlock) {
                // We reached a WithNode; the symbol must be scoped. Note that if the WithNode was not immediately
                // preceded by a block, this means we're currently processing its expression, not its body,
                // therefore it doesn't count.
                return true;
            }
            previousWasBlock = false;
        } else if (node instanceof Block) {
            if (((Block)node).getExistingSymbol(symbol.getName()) == symbol) {
                // We reached the block that defines the symbol without reaching either the function boundary, or a
                // WithNode. The symbol need not be scoped.
                return false;
            }
            previousWasBlock = true;
        } else {
            previousWasBlock = false;
        }
    }
    throw new AssertionError();
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
private static boolean isSplitArray(final LexicalContextNode expr) {
    if(!(expr instanceof ArrayLiteralNode)) {
        return false;
    }
    final List<ArrayUnit> units = ((ArrayLiteralNode)expr).getUnits();
    return !(units == null || units.isEmpty());
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
@Override
public <T extends LexicalContextNode> T push(final T node) {
    if (isWithBoundary(node)) {
        dynamicScopeCount++;
    } else if (node instanceof FunctionNode) {
        if (((FunctionNode)node).inDynamicContext()) {
            dynamicScopeCount++;
        }
        splitNodes.push(0);
    }
    return super.push(node);
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
/**
 * Determines if the symbol has to be a scope symbol. In general terms, it has to be a scope symbol if it can only
 * be reached from the current block by traversing a function node, a split node, or a with node.
 * @param symbol the symbol checked for needing to be a scope symbol
 * @return true if the symbol has to be a scope symbol.
 */
private boolean symbolNeedsToBeScope(final Symbol symbol) {
    if (symbol.isThis() || symbol.isInternal()) {
        return false;
    }

    final FunctionNode func = lc.getCurrentFunction();
    if ( func.allVarsInScope() || (!symbol.isBlockScoped() && func.isProgram())) {
        return true;
    }

    boolean previousWasBlock = false;
    for (final Iterator<LexicalContextNode> it = lc.getAllNodes(); it.hasNext();) {
        final LexicalContextNode node = it.next();
        if (node instanceof FunctionNode || isSplitLiteral(node)) {
            // We reached the function boundary or a splitting boundary without seeing a definition for the symbol.
            // It needs to be in scope.
            return true;
        } else if (node instanceof WithNode) {
            if (previousWasBlock) {
                // We reached a WithNode; the symbol must be scoped. Note that if the WithNode was not immediately
                // preceded by a block, this means we're currently processing its expression, not its body,
                // therefore it doesn't count.
                return true;
            }
            previousWasBlock = false;
        } else if (node instanceof Block) {
            if (((Block)node).getExistingSymbol(symbol.getName()) == symbol) {
                // We reached the block that defines the symbol without reaching either the function boundary, or a
                // WithNode. The symbol need not be scoped.
                return false;
            }
            previousWasBlock = true;
        } else {
            previousWasBlock = false;
        }
    }
    throw new AssertionError();
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
/**
 * Determines if the symbol has to be a scope symbol. In general terms, it
 * has to be a scope symbol if it can only be reached from the current block
 * by traversing a function node, a split node, or a with node.
 *
 * @param symbol the symbol checked for needing to be a scope symbol
 * @return true if the symbol has to be a scope symbol.
 */
private boolean symbolNeedsToBeScope(final Symbol symbol) {
    if (symbol.isThis() || symbol.isInternal()) {
        return false;
    }

    final FunctionNode func = lc.getCurrentFunction();
    if (func.allVarsInScope() || (!symbol.isBlockScoped() && func.isProgram())) {
        return true;
    }

    boolean previousWasBlock = false;
    for (final Iterator<LexicalContextNode> it = lc.getAllNodes(); it.hasNext();) {
        final LexicalContextNode node = it.next();
        if (node instanceof FunctionNode || isSplitLiteral(node)) {
            // We reached the function boundary or a splitting boundary without seeing a definition for the symbol.
            // It needs to be in scope.
            return true;
        } else if (node instanceof WithNode) {
            if (previousWasBlock) {
                // We reached a WithNode; the symbol must be scoped. Note that if the WithNode was not immediately
                // preceded by a block, this means we're currently processing its expression, not its body,
                // therefore it doesn't count.
                return true;
            }
            previousWasBlock = false;
        } else if (node instanceof Block) {
            if (((Block) node).getExistingSymbol(symbol.getName()) == symbol) {
                // We reached the block that defines the symbol without reaching either the function boundary, or a
                // WithNode. The symbol need not be scoped.
                return false;
            }
            previousWasBlock = true;
        } else {
            previousWasBlock = false;
        }
    }
    throw new AssertionError();
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
private boolean symbolNeedsToBeScope(Symbol symbol) {
    if (symbol.isThis() || symbol.isInternal()) {
        return false;
    }
    boolean previousWasBlock = false;
    for (final Iterator<LexicalContextNode> it = lc.getAllNodes(); it.hasNext();) {
        final LexicalContextNode node = it.next();
        if (node instanceof FunctionNode) {
            // We reached the function boundary without seeing a definition for the symbol - it needs to be in
            // scope.
            return true;
        } else if (node instanceof WithNode) {
            if (previousWasBlock) {
                // We reached a WithNode; the symbol must be scoped. Note that if the WithNode was not immediately
                // preceded by a block, this means we're currently processing its expression, not its body,
                // therefore it doesn't count.
                return true;
            }
            previousWasBlock = false;
        } else if (node instanceof Block) {
            if (((Block)node).getExistingSymbol(symbol.getName()) == symbol) {
                // We reached the block that defines the symbol without reaching either the function boundary, or a
                // WithNode. The symbol need not be scoped.
                return false;
            }
            previousWasBlock = true;
        } else {
            previousWasBlock = false;
        }
    }
    throw new AssertionError();
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
@Override
public <T extends LexicalContextNode> T push(final T node) {
    if (isDynamicScopeBoundary(node)) {
        ++dynamicScopeCount;
    }
    return super.push(node);
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
@Override
public <T extends LexicalContextNode> T pop(final T node) {
    final T popped = super.pop(node);
    if (isDynamicScopeBoundary(popped)) {
        --dynamicScopeCount;
    }
    if (node instanceof Block) {
        --nextFreeSlotsSize;
    }
    return popped;
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
private boolean isDynamicScopeBoundary(final LexicalContextNode node) {
    if (node instanceof Block) {
        // Block's immediate parent is a with node. Note we aren't testing for a WithNode, as that'd capture
        // processing of WithNode.expression too, but it should be unaffected.
        return !isEmpty() && peek() instanceof WithNode;
    } else if (node instanceof FunctionNode) {
        // Function has a direct eval in it (so a top-level "var ..." in the eval code can introduce a new
        // variable into the function's scope), and it isn't strict (as evals in strict functions get an
        // isolated scope).
        return isFunctionDynamicScope((FunctionNode)node);
    }
    return false;
}
 

import jdk.nashorn.internal.ir.LexicalContextNode; //导入依赖的package包/类
private boolean isWithBoundary(final LexicalContextNode node) {
    return node instanceof Block && !isEmpty() && peek() instanceof WithNode;
}