Examples with UnreachableBeginNode org.graalvm.compiler.nodes.UnreachableBeginNode used on opensource projects

Example 6 with UnreachableBeginNode

use of org.graalvm.compiler.nodes.UnreachableBeginNode in project graal by oracle.

the class PlaceholderLogicNode method assignNecessaryFrameStates.

private void assignNecessaryFrameStates(ValueNode replacee, UnmodifiableEconomicMap<Node, Node> duplicates, FixedNode replaceeGraphCFGPredecessor) {
    FrameState stateAfter = null;
    if (replacee instanceof StateSplit && ((StateSplit) replacee).hasSideEffect()) {
        stateAfter = ((StateSplit) replacee).stateAfter();
        GraalError.guarantee(stateAfter != null, "Statesplit with side-effect %s needs a framestate", replacee);
    } else {
        /*
             * We dont have a state split as a replacee, thus we take the prev state as the state
             * after for the node in the snippet.
             */
        stateAfter = GraphUtil.findLastFrameState(replaceeGraphCFGPredecessor);
    }
    final ExceptionObjectNode exceptionObject;
    if (replacee instanceof WithExceptionNode) {
        WithExceptionNode withExceptionNode = (WithExceptionNode) replacee;
        if (withExceptionNode.exceptionEdge() instanceof ExceptionObjectNode) {
            exceptionObject = (ExceptionObjectNode) withExceptionNode.exceptionEdge();
        } else {
            GraalError.guarantee(withExceptionNode.exceptionEdge() instanceof UnreachableBeginNode, "Unexpected exception edge %s", withExceptionNode.exceptionEdge());
            exceptionObject = null;
        }
    } else {
        exceptionObject = null;
    }
    NodeMap<NodeStateAssignment> assignedStateMappings = frameStateAssignment.getStateMapping();
    MapCursor<Node, NodeStateAssignment> stateAssignments = assignedStateMappings.getEntries();
    while (stateAssignments.advance()) {
        Node nodeRequiringState = stateAssignments.getKey();
        if (nodeRequiringState instanceof DeoptBciSupplier) {
            if (replacee instanceof DeoptBciSupplier) {
                ((DeoptBciSupplier) duplicates.get(nodeRequiringState)).setBci(((DeoptBciSupplier) replacee).bci());
            }
        }
        NodeStateAssignment assignment = stateAssignments.getValue();
        switch(assignment) {
            case AFTER_BCI:
                setReplaceeGraphStateAfter(nodeRequiringState, replacee, duplicates, stateAfter);
                break;
            case AFTER_EXCEPTION_BCI:
                if (nodeRequiringState instanceof ExceptionObjectNode) {
                    ExceptionObjectNode newExceptionObject = (ExceptionObjectNode) duplicates.get(nodeRequiringState);
                    rewireExceptionFrameState(exceptionObject, newExceptionObject, newExceptionObject);
                } else if (nodeRequiringState instanceof MergeNode) {
                    MergeNode mergeNode = (MergeNode) duplicates.get(nodeRequiringState);
                    rewireExceptionFrameState(exceptionObject, getExceptionValueFromMerge(mergeNode), mergeNode);
                } else {
                    GraalError.shouldNotReachHere("Unexpected exception state node: " + nodeRequiringState);
                }
                break;
            case BEFORE_BCI:
                FrameState stateBeforeSnippet = GraphUtil.findLastFrameState(replaceeGraphCFGPredecessor);
                ((StateSplit) duplicates.get(nodeRequiringState)).setStateAfter(stateBeforeSnippet.duplicate());
                break;
            case INVALID:
                /*
                     * We cannot assign a proper frame state for this snippet's node since there are
                     * effects which cannot be represented by a single state at the node
                     */
                throw GraalError.shouldNotReachHere("Invalid snippet replacing a node before frame state assignment with node " + nodeRequiringState + " for replacee " + replacee);
            default:
                throw GraalError.shouldNotReachHere("Unknown StateAssigment:" + assignment);
        }
        replacee.graph().getDebug().dump(DebugContext.VERY_DETAILED_LEVEL, replacee.graph(), "After duplicating after state for node %s in snippet", duplicates.get(nodeRequiringState));
    }
}

Example 7 with UnreachableBeginNode

use of org.graalvm.compiler.nodes.UnreachableBeginNode in project graal by oracle.

the class PlaceholderLogicNode method instantiate.

/**
 * Replaces a given fixed node with this specialized snippet.
 *
 * @param metaAccess
 * @param replacee the node that will be replaced
 * @param replacer object that replaces the usages of {@code replacee}
 * @param args the arguments to be bound to the flattened positional parameters of the snippet
 * @param killReplacee is true, the replacee node is deleted
 * @return the map of duplicated nodes (original -> duplicate)
 */
@SuppressWarnings("try")
public UnmodifiableEconomicMap<Node, Node> instantiate(MetaAccessProvider metaAccess, FixedNode replacee, UsageReplacer replacer, Arguments args, boolean killReplacee) {
    if (!(replacee instanceof ControlSinkNode)) {
        /*
             * For all use cases of this, the replacee is killed sooner ({@code killReplacee ==
             * true}) or later (by the caller of this method). However, we cannot do that if the
             * snippet does not have a return node we because that means we kill the {@code
             * replacee.next()} which might be connected to a merge whose next node has not yet been
             * lowered [GR-33909].
             */
        GraalError.guarantee(this.returnNode != null, "Cannot kill %s because snippet %s does not have a return node", replacee, this);
    }
    DebugContext debug = replacee.getDebug();
    assert assertSnippetKills(replacee);
    try (DebugCloseable a = args.info.instantiationTimer.start(debug)) {
        args.info.instantiationCounter.increment(debug);
        // Inline the snippet nodes, replacing parameters with the given args in the process
        final FixedNode replaceeGraphPredecessor = (FixedNode) replacee.predecessor();
        StartNode entryPointNode = snippet.start();
        FixedNode firstCFGNode = entryPointNode.next();
        StructuredGraph replaceeGraph = replacee.graph();
        EconomicMap<Node, Node> replacements = bind(replaceeGraph, metaAccess, args);
        replacements.put(entryPointNode, AbstractBeginNode.prevBegin(replacee));
        EconomicMap<Node, Node> duplicates = inlineSnippet(replacee, debug, replaceeGraph, replacements);
        // Re-wire the control flow graph around the replacee
        FixedNode firstCFGNodeDuplicate = (FixedNode) duplicates.get(firstCFGNode);
        replacee.replaceAtPredecessor(firstCFGNodeDuplicate);
        if (replacee.graph().getGuardsStage().areFrameStatesAtSideEffects()) {
            boolean replaceeHasSideEffect = replacee instanceof StateSplit && ((StateSplit) replacee).hasSideEffect();
            boolean replacementHasSideEffect = !sideEffectNodes.isEmpty();
            if (replacementHasSideEffect) {
                GraalError.guarantee(replaceeHasSideEffect, "Lowering node %s without side-effect to snippet %s with sideeffects=%s", replacee, info, this.sideEffectNodes);
            }
        }
        updateStamps(replacee, duplicates);
        rewireMemoryGraph(replacee, duplicates);
        rewireFrameStates(replacee, duplicates, replaceeGraphPredecessor);
        // Replace all usages of the replacee with the value returned by the snippet
        ValueNode returnValue = null;
        AbstractBeginNode originalWithExceptionNextNode = null;
        if (returnNode != null && !(replacee instanceof ControlSinkNode)) {
            ReturnNode returnDuplicate = (ReturnNode) duplicates.get(returnNode);
            returnValue = returnDuplicate.result();
            if (returnValue == null && replacee.usages().isNotEmpty() && replacee instanceof MemoryKill) {
                replacer.replace(replacee, null);
            } else {
                assert returnValue != null || replacee.hasNoUsages();
                replacer.replace(replacee, returnValue);
            }
            if (returnDuplicate.isAlive()) {
                FixedNode next = null;
                if (replacee instanceof FixedWithNextNode) {
                    FixedWithNextNode fwn = (FixedWithNextNode) replacee;
                    next = fwn.next();
                    fwn.setNext(null);
                } else if (replacee instanceof WithExceptionNode) {
                    WithExceptionNode withExceptionNode = (WithExceptionNode) replacee;
                    next = originalWithExceptionNextNode = withExceptionNode.next();
                    withExceptionNode.setNext(null);
                }
                returnDuplicate.replaceAndDelete(next);
            }
        }
        if (unwindPath != null && unwindPath.isAlive()) {
            GraalError.guarantee(replacee.graph().isBeforeStage(StageFlag.FLOATING_READS) || replacee instanceof WithExceptionNode, "Using a snippet with an UnwindNode after floating reads would require support for the memory graph (unless the replacee has an exception edge)");
            GraalError.guarantee(replacee instanceof WithExceptionNode, "Snippet has an UnwindNode, but replacee is not a node with an exception handler");
            // snippet exception handler
            UnwindNode snippetUnwindDuplicate = (UnwindNode) duplicates.get(unwindPath);
            ValueNode snippetExceptionValue = snippetUnwindDuplicate.exception();
            FixedWithNextNode snippetUnwindPath = (FixedWithNextNode) snippetUnwindDuplicate.predecessor();
            GraalError.guarantee(!(snippetExceptionValue instanceof ExceptionObjectNode) || snippetUnwindPath == snippetExceptionValue, "Snippet unwind predecessor must be the exception object %s: %s", snippetUnwindPath, snippetExceptionValue);
            GraalError.guarantee(!(snippetUnwindPath instanceof MergeNode) || snippetExceptionValue instanceof PhiNode, "If the snippet unwind predecessor is a merge node, the exception object must be a phi %s: %s", snippetUnwindPath, snippetExceptionValue);
            // replacee exception handler
            WithExceptionNode replaceeWithExceptionNode = (WithExceptionNode) replacee;
            AbstractBeginNode exceptionEdge = replaceeWithExceptionNode.exceptionEdge();
            if (exceptionEdge instanceof ExceptionObjectNode) {
                /*
                     * The exception object node is a begin node, i.e., it can be used as an anchor
                     * for other nodes, thus we need to re-route them to a valid anchor, i.e. the
                     * begin node of the unwind block.
                     */
                GraalError.guarantee(exceptionEdge.usages().filter(x -> x instanceof GuardedNode && ((GuardedNode) x).getGuard() == exceptionEdge).count() == 0, "Must not have guards attached to exception object node %s", exceptionEdge);
                replaceeWithExceptionNode.setExceptionEdge(null);
                // replace the old exception object with the one
                exceptionEdge.replaceAtUsages(snippetExceptionValue);
                GraalError.guarantee(originalWithExceptionNextNode != null, "Need to have next node to link placeholder to: %s", replacee);
                // replace exceptionEdge with snippetUnwindPath
                replaceExceptionObjectNode(exceptionEdge, snippetUnwindPath);
                GraphUtil.killCFG(snippetUnwindDuplicate);
            } else {
                GraalError.guarantee(exceptionEdge instanceof UnreachableBeginNode, "Unexpected exception edge: %s", exceptionEdge);
                markExceptionsUnreachable(unwindPath.exception(), duplicates);
            }
        } else {
            /*
                 * Since the snippet unwindPath is null or has been deleted, a placeholder
                 * WithExceptionNode needs to be added for any WithExceptionNode replacee. This
                 * placeholder WithExceptionNode temporarily preserves the replacee's original
                 * exception edge and is needed because lowering should not remove edges from the
                 * original CFG.
                 */
            if (replacee instanceof WithExceptionNode) {
                GraalError.guarantee(originalWithExceptionNextNode != null, "Need to have next node to link placeholder to: %s", replacee);
                WithExceptionNode newExceptionNode = replacee.graph().add(new PlaceholderWithExceptionNode());
                /*
                     * First attaching placeholder as predecessor of original WithExceptionNode next
                     * edge.
                     */
                ((FixedWithNextNode) originalWithExceptionNextNode.predecessor()).setNext(newExceptionNode);
                newExceptionNode.setNext(originalWithExceptionNextNode);
                /* Now connecting exception edge. */
                WithExceptionNode oldExceptionNode = (WithExceptionNode) replacee;
                AbstractBeginNode exceptionEdge = oldExceptionNode.exceptionEdge();
                oldExceptionNode.setExceptionEdge(null);
                newExceptionNode.setExceptionEdge(exceptionEdge);
            }
        }
        if (artificialReturnCondition != null) {
            ((PlaceholderLogicNode) duplicates.get(artificialReturnCondition)).markForDeletion();
        }
        if (fallbackInvoke != null) {
            GraalError.guarantee(replacee instanceof MacroWithExceptionNode, "%s can only be used in snippets replacing %s", FallbackInvokeWithExceptionNode.class.getSimpleName(), MacroWithExceptionNode.class.getSimpleName());
            WithExceptionNode fallbackInvokeNode = (WithExceptionNode) duplicates.get(fallbackInvoke);
            MacroWithExceptionNode macroNode = (MacroWithExceptionNode) replacee;
            // create fallback invoke
            InvokeWithExceptionNode invoke = macroNode.createInvoke(returnValue);
            // replace placeholder
            replaceeGraph.replaceWithExceptionSplit(fallbackInvokeNode, invoke);
            // register the invoke as the replacement for the fallback invoke
            duplicates.put(fallbackInvoke, invoke);
        }
        if (killReplacee) {
            // Remove the replacee from its graph
            GraphUtil.killCFG(replacee);
        }
        debug.dump(DebugContext.DETAILED_LEVEL, replaceeGraph, "After lowering %s with %s", replacee, this);
        return duplicates;
    }
}