Java DeoptimizationReason.UnreachedCode方法代码示例

import jdk.vm.ci.meta.DeoptimizationReason; //导入方法依赖的package包/类
private static void tryUseTrappingNullCheck(AbstractDeoptimizeNode deopt, Node predecessor, DeoptimizationReason deoptimizationReason, JavaConstant speculation, long implicitNullCheckLimit) {
    if (deoptimizationReason != DeoptimizationReason.NullCheckException && deoptimizationReason != DeoptimizationReason.UnreachedCode) {
        return;
    }
    if (speculation != null && !speculation.equals(JavaConstant.NULL_POINTER)) {
        return;
    }
    if (predecessor instanceof AbstractMergeNode) {
        AbstractMergeNode merge = (AbstractMergeNode) predecessor;
        if (merge.phis().isEmpty()) {
            for (AbstractEndNode end : merge.cfgPredecessors().snapshot()) {
                checkPredecessor(deopt, end.predecessor(), deoptimizationReason, implicitNullCheckLimit);
            }
        }
    } else if (predecessor instanceof AbstractBeginNode) {
        checkPredecessor(deopt, predecessor, deoptimizationReason, implicitNullCheckLimit);
    }
}
 

import jdk.vm.ci.meta.DeoptimizationReason; //导入方法依赖的package包/类
private static void replaceWithTrappingNullCheck(AbstractDeoptimizeNode deopt, IfNode ifNode, LogicNode condition, DeoptimizationReason deoptimizationReason, long implicitNullCheckLimit) {
    DebugContext debug = deopt.getDebug();
    counterTrappingNullCheck.increment(debug);
    if (deopt instanceof DynamicDeoptimizeNode) {
        counterTrappingNullCheckDynamicDeoptimize.increment(debug);
    }
    if (deoptimizationReason == DeoptimizationReason.UnreachedCode) {
        counterTrappingNullCheckUnreached.increment(debug);
    }
    IsNullNode isNullNode = (IsNullNode) condition;
    AbstractBeginNode nonTrappingContinuation = ifNode.falseSuccessor();
    AbstractBeginNode trappingContinuation = ifNode.trueSuccessor();

    DeoptimizingFixedWithNextNode trappingNullCheck = null;
    FixedNode nextNonTrapping = nonTrappingContinuation.next();
    ValueNode value = isNullNode.getValue();
    if (OptImplicitNullChecks.getValue(ifNode.graph().getOptions()) && implicitNullCheckLimit > 0) {
        if (nextNonTrapping instanceof FixedAccessNode) {
            FixedAccessNode fixedAccessNode = (FixedAccessNode) nextNonTrapping;
            if (fixedAccessNode.canNullCheck()) {
                AddressNode address = fixedAccessNode.getAddress();
                ValueNode base = address.getBase();
                ValueNode index = address.getIndex();
                // allow for architectures which cannot fold an
                // intervening uncompress out of the address chain
                if (base != null && base instanceof CompressionNode) {
                    base = ((CompressionNode) base).getValue();
                }
                if (index != null && index instanceof CompressionNode) {
                    index = ((CompressionNode) index).getValue();
                }
                if (((base == value && index == null) || (base == null && index == value)) && address.getMaxConstantDisplacement() < implicitNullCheckLimit) {
                    // Opportunity for implicit null check as part of an existing read found!
                    fixedAccessNode.setStateBefore(deopt.stateBefore());
                    fixedAccessNode.setNullCheck(true);
                    deopt.graph().removeSplit(ifNode, nonTrappingContinuation);
                    trappingNullCheck = fixedAccessNode;
                    counterTrappingNullCheckExistingRead.increment(debug);
                }
            }
        }
    }

    if (trappingNullCheck == null) {
        // Need to add a null check node.
        trappingNullCheck = deopt.graph().add(new NullCheckNode(value));
        deopt.graph().replaceSplit(ifNode, trappingNullCheck, nonTrappingContinuation);
    }

    trappingNullCheck.setStateBefore(deopt.stateBefore());

    /*
     * We now have the pattern NullCheck/BeginNode/... It's possible some node is using the
     * BeginNode as a guard input, so replace guard users of the Begin with the NullCheck and
     * then remove the Begin from the graph.
     */
    nonTrappingContinuation.replaceAtUsages(InputType.Guard, trappingNullCheck);

    if (nonTrappingContinuation instanceof BeginNode) {
        GraphUtil.unlinkFixedNode(nonTrappingContinuation);
        nonTrappingContinuation.safeDelete();
    }

    GraphUtil.killCFG(trappingContinuation);
    GraphUtil.tryKillUnused(isNullNode);
}
 

import jdk.vm.ci.meta.DeoptimizationReason; //导入方法依赖的package包/类
public DeoptimizationReason convertDeoptReason(int reason) {
    HotSpotVMConfig config = runtime.getConfig();
    if (reason == config.deoptReasonNone) {
        return DeoptimizationReason.None;
    }
    if (reason == config.deoptReasonNullCheck) {
        return DeoptimizationReason.NullCheckException;
    }
    if (reason == config.deoptReasonRangeCheck) {
        return DeoptimizationReason.BoundsCheckException;
    }
    if (reason == config.deoptReasonClassCheck) {
        return DeoptimizationReason.ClassCastException;
    }
    if (reason == config.deoptReasonArrayCheck) {
        return DeoptimizationReason.ArrayStoreException;
    }
    if (reason == config.deoptReasonUnreached0) {
        return DeoptimizationReason.UnreachedCode;
    }
    if (reason == config.deoptReasonTypeCheckInlining) {
        return DeoptimizationReason.TypeCheckedInliningViolated;
    }
    if (reason == config.deoptReasonOptimizedTypeCheck) {
        return DeoptimizationReason.OptimizedTypeCheckViolated;
    }
    if (reason == config.deoptReasonNotCompiledExceptionHandler) {
        return DeoptimizationReason.NotCompiledExceptionHandler;
    }
    if (reason == config.deoptReasonUnresolved) {
        return DeoptimizationReason.Unresolved;
    }
    if (reason == config.deoptReasonJsrMismatch) {
        return DeoptimizationReason.JavaSubroutineMismatch;
    }
    if (reason == config.deoptReasonDiv0Check) {
        return DeoptimizationReason.ArithmeticException;
    }
    if (reason == config.deoptReasonConstraint) {
        return DeoptimizationReason.RuntimeConstraint;
    }
    if (reason == config.deoptReasonLoopLimitCheck) {
        return DeoptimizationReason.LoopLimitCheck;
    }
    if (reason == config.deoptReasonAliasing) {
        return DeoptimizationReason.Aliasing;
    }
    if (reason == config.deoptReasonTransferToInterpreter) {
        return DeoptimizationReason.TransferToInterpreter;
    }
    throw new JVMCIError("%x", reason);
}
 

import jdk.vm.ci.meta.DeoptimizationReason; //导入方法依赖的package包/类
private static void replaceWithTrappingNullCheck(AbstractDeoptimizeNode deopt, IfNode ifNode, LogicNode condition, DeoptimizationReason deoptimizationReason, long implicitNullCheckLimit) {
    counterTrappingNullCheck.increment();
    if (deopt instanceof DynamicDeoptimizeNode) {
        counterTrappingNullCheckDynamicDeoptimize.increment();
    }
    if (deoptimizationReason == DeoptimizationReason.UnreachedCode) {
        counterTrappingNullCheckUnreached.increment();
    }
    IsNullNode isNullNode = (IsNullNode) condition;
    AbstractBeginNode nonTrappingContinuation = ifNode.falseSuccessor();
    AbstractBeginNode trappingContinuation = ifNode.trueSuccessor();

    DeoptimizingFixedWithNextNode trappingNullCheck = null;
    FixedNode nextNonTrapping = nonTrappingContinuation.next();
    ValueNode value = isNullNode.getValue();
    if (OptImplicitNullChecks.getValue(ifNode.graph().getOptions()) && implicitNullCheckLimit > 0) {
        if (nextNonTrapping instanceof FixedAccessNode) {
            FixedAccessNode fixedAccessNode = (FixedAccessNode) nextNonTrapping;
            if (fixedAccessNode.canNullCheck()) {
                AddressNode address = fixedAccessNode.getAddress();
                ValueNode base = address.getBase();
                ValueNode index = address.getIndex();
                if (((base == value && index == null) || (base == null && index == value)) && address.getMaxConstantDisplacement() < implicitNullCheckLimit) {
                    // Opportunity for implicit null check as part of an existing read found!
                    fixedAccessNode.setStateBefore(deopt.stateBefore());
                    fixedAccessNode.setNullCheck(true);
                    deopt.graph().removeSplit(ifNode, nonTrappingContinuation);
                    trappingNullCheck = fixedAccessNode;
                    counterTrappingNullCheckExistingRead.increment();
                }
            }
        }
    }

    if (trappingNullCheck == null) {
        // Need to add a null check node.
        trappingNullCheck = deopt.graph().add(new NullCheckNode(value));
        deopt.graph().replaceSplit(ifNode, trappingNullCheck, nonTrappingContinuation);
    }

    trappingNullCheck.setStateBefore(deopt.stateBefore());

    /*
     * We now have the pattern NullCheck/BeginNode/... It's possible some node is using the
     * BeginNode as a guard input, so replace guard users of the Begin with the NullCheck and
     * then remove the Begin from the graph.
     */
    nonTrappingContinuation.replaceAtUsages(InputType.Guard, trappingNullCheck);

    if (nonTrappingContinuation instanceof BeginNode) {
        GraphUtil.unlinkFixedNode(nonTrappingContinuation);
        nonTrappingContinuation.safeDelete();
    }

    GraphUtil.killCFG(trappingContinuation);
    GraphUtil.tryKillUnused(isNullNode);
}