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

Example 1 with LoopExitNode

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

the class GraphUtil method fixSurvivingAffectedMerges.

private static void fixSurvivingAffectedMerges(EconomicSet<Node> markedNodes, EconomicMap<AbstractMergeNode, List<AbstractEndNode>> unmarkedMerges) {
    MapCursor<AbstractMergeNode, List<AbstractEndNode>> cursor = unmarkedMerges.getEntries();
    while (cursor.advance()) {
        AbstractMergeNode merge = cursor.getKey();
        for (AbstractEndNode end : cursor.getValue()) {
            merge.removeEnd(end);
        }
        if (merge.phiPredecessorCount() == 1) {
            if (merge instanceof LoopBeginNode) {
                LoopBeginNode loopBegin = (LoopBeginNode) merge;
                assert merge.forwardEndCount() == 1;
                for (LoopExitNode loopExit : loopBegin.loopExits().snapshot()) {
                    if (markedNodes.contains(loopExit)) {
                        /*
                             * disconnect from loop begin so that reduceDegenerateLoopBegin doesn't
                             * transform it into a new beginNode
                             */
                        loopExit.replaceFirstInput(loopBegin, null);
                    }
                }
                merge.graph().reduceDegenerateLoopBegin(loopBegin);
            } else {
                merge.graph().reduceTrivialMerge(merge);
            }
        } else {
            assert merge.phiPredecessorCount() > 1 : merge;
        }
    }
}

Example 2 with LoopExitNode

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

the class BytecodeParser method parseAndInlineCallee.

protected void parseAndInlineCallee(ResolvedJavaMethod targetMethod, ValueNode[] args, IntrinsicContext calleeIntrinsicContext) {
    FixedWithNextNode calleeBeforeUnwindNode = null;
    ValueNode calleeUnwindValue = null;
    try (IntrinsicScope s = calleeIntrinsicContext != null && !parsingIntrinsic() ? new IntrinsicScope(this, targetMethod.getSignature().toParameterKinds(!targetMethod.isStatic()), args) : null) {
        BytecodeParser parser = graphBuilderInstance.createBytecodeParser(graph, this, targetMethod, INVOCATION_ENTRY_BCI, calleeIntrinsicContext);
        FrameStateBuilder startFrameState = new FrameStateBuilder(parser, parser.code, graph);
        if (!targetMethod.isStatic()) {
            args[0] = nullCheckedValue(args[0]);
        }
        startFrameState.initializeFromArgumentsArray(args);
        parser.build(this.lastInstr, startFrameState);
        if (parser.returnDataList == null) {
            /* Callee does not return. */
            lastInstr = null;
        } else {
            ValueNode calleeReturnValue;
            MergeNode returnMergeNode = null;
            if (s != null) {
                s.returnDataList = parser.returnDataList;
            }
            if (parser.returnDataList.size() == 1) {
                /* Callee has a single return, we can continue parsing at that point. */
                ReturnToCallerData singleReturnData = parser.returnDataList.get(0);
                lastInstr = singleReturnData.beforeReturnNode;
                calleeReturnValue = singleReturnData.returnValue;
            } else {
                assert parser.returnDataList.size() > 1;
                /* Callee has multiple returns, we need to insert a control flow merge. */
                returnMergeNode = graph.add(new MergeNode());
                calleeReturnValue = ValueMergeUtil.mergeValueProducers(returnMergeNode, parser.returnDataList, returnData -> returnData.beforeReturnNode, returnData -> returnData.returnValue);
            }
            if (calleeReturnValue != null) {
                frameState.push(targetMethod.getSignature().getReturnKind().getStackKind(), calleeReturnValue);
            }
            if (returnMergeNode != null) {
                returnMergeNode.setStateAfter(createFrameState(stream.nextBCI(), returnMergeNode));
                lastInstr = finishInstruction(returnMergeNode, frameState);
            }
        }
        /*
             * Propagate any side effects into the caller when parsing intrinsics.
             */
        if (parser.frameState.isAfterSideEffect() && parsingIntrinsic()) {
            for (StateSplit sideEffect : parser.frameState.sideEffects()) {
                frameState.addSideEffect(sideEffect);
            }
        }
        calleeBeforeUnwindNode = parser.getBeforeUnwindNode();
        if (calleeBeforeUnwindNode != null) {
            calleeUnwindValue = parser.getUnwindValue();
            assert calleeUnwindValue != null;
        }
    }
    /*
         * Method handleException will call createTarget, which wires this exception edge to the
         * corresponding exception dispatch block in the caller. In the case where it wires to the
         * caller's unwind block, any FrameState created meanwhile, e.g., FrameState for
         * LoopExitNode, would be instantiated with AFTER_EXCEPTION_BCI. Such frame states should
         * not be fixed by IntrinsicScope.close, as they denote the states of the caller. Thus, the
         * following code should be placed outside the IntrinsicScope, so that correctly created
         * FrameStates are not replaced.
         */
    if (calleeBeforeUnwindNode != null) {
        calleeBeforeUnwindNode.setNext(handleException(calleeUnwindValue, bci(), false));
    }
}

Example 3 with LoopExitNode

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

the class BytecodeParser method checkLoopExit.

private Target checkLoopExit(FixedNode target, BciBlock targetBlock, FrameStateBuilder state) {
    if (currentBlock != null) {
        long exits = currentBlock.loops & ~targetBlock.loops;
        if (exits != 0) {
            LoopExitNode firstLoopExit = null;
            LoopExitNode lastLoopExit = null;
            int pos = 0;
            ArrayList<BciBlock> exitLoops = new ArrayList<>(Long.bitCount(exits));
            do {
                long lMask = 1L << pos;
                if ((exits & lMask) != 0) {
                    exitLoops.add(blockMap.getLoopHeader(pos));
                    exits &= ~lMask;
                }
                pos++;
            } while (exits != 0);
            Collections.sort(exitLoops, new Comparator<BciBlock>() {

                @Override
                public int compare(BciBlock o1, BciBlock o2) {
                    return Long.bitCount(o2.loops) - Long.bitCount(o1.loops);
                }
            });
            int bci = targetBlock.startBci;
            if (targetBlock instanceof ExceptionDispatchBlock) {
                bci = ((ExceptionDispatchBlock) targetBlock).deoptBci;
            }
            FrameStateBuilder newState = state.copy();
            for (BciBlock loop : exitLoops) {
                LoopBeginNode loopBegin = (LoopBeginNode) getFirstInstruction(loop);
                LoopExitNode loopExit = graph.add(new LoopExitNode(loopBegin));
                if (lastLoopExit != null) {
                    lastLoopExit.setNext(loopExit);
                }
                if (firstLoopExit == null) {
                    firstLoopExit = loopExit;
                }
                lastLoopExit = loopExit;
                debug.log("Target %s Exits %s, scanning framestates...", targetBlock, loop);
                newState.clearNonLiveLocals(targetBlock, liveness, true);
                newState.insertLoopProxies(loopExit, getEntryState(loop));
                loopExit.setStateAfter(newState.create(bci, loopExit));
            }
            lastLoopExit.setNext(target);
            return new Target(firstLoopExit, newState);
        }
    }
    return new Target(target, state);
}

Example 4 with LoopExitNode

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

the class LoopTransformations method insertPrePostLoops.

// This function splits candidate loops into pre, main and post loops,
// dividing the iteration space to facilitate the majority of iterations
// being executed in a main loop, which will have RCE implemented upon it.
// The initial loop form is constrained to single entry/exit, but can have
// flow. The translation looks like:
// 
// @formatter:off
// 
// (Simple Loop entry)                   (Pre Loop Entry)
// |                                  |
// (LoopBeginNode)                    (LoopBeginNode)
// |                                  |
// (Loop Control Test)<------   ==>  (Loop control Test)<------
// /               \       \         /               \       \
// (Loop Exit)      (Loop Body) |    (Loop Exit)      (Loop Body) |
// |                |       |        |                |       |
// (continue code)     (Loop End)  |  if (M < length)*   (Loop End)  |
// \       /       /      \           \      /
// ----->        /       |            ----->
// /  if ( ... )*
// /     /       \
// /     /         \
// /     /           \
// |     /     (Main Loop Entry)
// |    |             |
// |    |      (LoopBeginNode)
// |    |             |
// |    |     (Loop Control Test)<------
// |    |      /               \        \
// |    |  (Loop Exit)      (Loop Body) |
// \   \      |                |       |
// \   \     |            (Loop End)  |
// \   \    |                \       /
// \   \   |                 ------>
// \   \  |
// (Main Loop Merge)*
// |
// (Post Loop Entry)
// |
// (LoopBeginNode)
// |
// (Loop Control Test)<-----
// /               \       \
// (Loop Exit)     (Loop Body) |
// |               |       |
// (continue code)    (Loop End)  |
// \      /
// ----->
// 
// Key: "*" = optional.
// @formatter:on
// 
// The value "M" is the maximal value of the loop trip for the original
// loop. The value of "length" is applicable to the number of arrays found
// in the loop but is reduced if some or all of the arrays are known to be
// the same length as "M". The maximum number of tests can be equal to the
// number of arrays in the loop, where multiple instances of an array are
// subsumed into a single test for that arrays length.
// 
// If the optional main loop entry tests are absent, the Pre Loop exit
// connects to the Main loops entry and there is no merge hanging off the
// main loops exit to converge flow from said tests. All split use data
// flow is mitigated through phi(s) in the main merge if present and
// passed through the main and post loop phi(s) from the originating pre
// loop with final phi(s) and data flow patched to the "continue code".
// The pre loop is constrained to one iteration for now and will likely
// be updated to produce vector alignment if applicable.
public static LoopBeginNode insertPrePostLoops(LoopEx loop) {
    StructuredGraph graph = loop.loopBegin().graph();
    graph.getDebug().log("LoopTransformations.insertPrePostLoops %s", loop);
    LoopFragmentWhole preLoop = loop.whole();
    CountedLoopInfo preCounted = loop.counted();
    IfNode preLimit = preCounted.getLimitTest();
    assert preLimit != null;
    LoopBeginNode preLoopBegin = loop.loopBegin();
    InductionVariable preIv = preCounted.getCounter();
    LoopExitNode preLoopExitNode = preLoopBegin.getSingleLoopExit();
    FixedNode continuationNode = preLoopExitNode.next();
    // Each duplication is inserted after the original, ergo create the post loop first
    LoopFragmentWhole mainLoop = preLoop.duplicate();
    LoopFragmentWhole postLoop = preLoop.duplicate();
    preLoopBegin.incrementSplits();
    preLoopBegin.incrementSplits();
    preLoopBegin.setPreLoop();
    graph.getDebug().dump(DebugContext.VERBOSE_LEVEL, graph, "After duplication");
    LoopBeginNode mainLoopBegin = mainLoop.getDuplicatedNode(preLoopBegin);
    mainLoopBegin.setMainLoop();
    LoopBeginNode postLoopBegin = postLoop.getDuplicatedNode(preLoopBegin);
    postLoopBegin.setPostLoop();
    EndNode postEndNode = getBlockEndAfterLoopExit(postLoopBegin);
    AbstractMergeNode postMergeNode = postEndNode.merge();
    LoopExitNode postLoopExitNode = postLoopBegin.getSingleLoopExit();
    // Update the main loop phi initialization to carry from the pre loop
    for (PhiNode prePhiNode : preLoopBegin.phis()) {
        PhiNode mainPhiNode = mainLoop.getDuplicatedNode(prePhiNode);
        mainPhiNode.setValueAt(0, prePhiNode);
    }
    EndNode mainEndNode = getBlockEndAfterLoopExit(mainLoopBegin);
    AbstractMergeNode mainMergeNode = mainEndNode.merge();
    AbstractEndNode postEntryNode = postLoopBegin.forwardEnd();
    // In the case of no Bounds tests, we just flow right into the main loop
    AbstractBeginNode mainLandingNode = BeginNode.begin(postEntryNode);
    LoopExitNode mainLoopExitNode = mainLoopBegin.getSingleLoopExit();
    mainLoopExitNode.setNext(mainLandingNode);
    preLoopExitNode.setNext(mainLoopBegin.forwardEnd());
    // Add and update any phi edges as per merge usage as needed and update usages
    processPreLoopPhis(loop, mainLoop, postLoop);
    continuationNode.predecessor().clearSuccessors();
    postLoopExitNode.setNext(continuationNode);
    cleanupMerge(postMergeNode, postLoopExitNode);
    cleanupMerge(mainMergeNode, mainLandingNode);
    // Change the preLoop to execute one iteration for now
    updateMainLoopLimit(preLimit, preIv, mainLoop);
    updatePreLoopLimit(preLimit, preIv, preCounted);
    preLoopBegin.setLoopFrequency(1);
    mainLoopBegin.setLoopFrequency(Math.max(0.0, mainLoopBegin.loopFrequency() - 2));
    postLoopBegin.setLoopFrequency(Math.max(0.0, postLoopBegin.loopFrequency() - 1));
    // The pre and post loops don't require safepoints at all
    for (SafepointNode safepoint : preLoop.nodes().filter(SafepointNode.class)) {
        graph.removeFixed(safepoint);
    }
    for (SafepointNode safepoint : postLoop.nodes().filter(SafepointNode.class)) {
        graph.removeFixed(safepoint);
    }
    graph.getDebug().dump(DebugContext.DETAILED_LEVEL, graph, "InsertPrePostLoops %s", loop);
    return mainLoopBegin;
}

Example 5 with LoopExitNode

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

the class LoopFragmentInside method patchPeeling.

private void patchPeeling(LoopFragmentInside peel) {
    LoopBeginNode loopBegin = loop().loopBegin();
    StructuredGraph graph = loopBegin.graph();
    List<PhiNode> newPhis = new LinkedList<>();
    NodeBitMap usagesToPatch = nodes.copy();
    for (LoopExitNode exit : exits()) {
        markStateNodes(exit, usagesToPatch);
        for (ProxyNode proxy : exit.proxies()) {
            usagesToPatch.markAndGrow(proxy);
        }
    }
    markStateNodes(loopBegin, usagesToPatch);
    List<PhiNode> oldPhis = loopBegin.phis().snapshot();
    for (PhiNode phi : oldPhis) {
        if (phi.hasNoUsages()) {
            continue;
        }
        ValueNode first;
        if (loopBegin.loopEnds().count() == 1) {
            // back edge value
            ValueNode b = phi.valueAt(loopBegin.loopEnds().first());
            // corresponding value in the peel
            first = peel.prim(b);
        } else {
            first = peel.mergedInitializers.get(phi);
        }
        // create a new phi (we don't patch the old one since some usages of the old one may
        // still be valid)
        PhiNode newPhi = patchPhi(graph, phi, loopBegin);
        newPhi.addInput(first);
        for (LoopEndNode end : loopBegin.orderedLoopEnds()) {
            newPhi.addInput(phi.valueAt(end));
        }
        peel.putDuplicatedNode(phi, newPhi);
        newPhis.add(newPhi);
        for (Node usage : phi.usages().snapshot()) {
            // patch only usages that should use the new phi ie usages that were peeled
            if (usagesToPatch.isMarkedAndGrow(usage)) {
                usage.replaceFirstInput(phi, newPhi);
            }
        }
    }
    // new corresponding phis
    for (PhiNode phi : newPhis) {
        for (int i = 0; i < phi.valueCount(); i++) {
            ValueNode v = phi.valueAt(i);
            if (loopBegin.isPhiAtMerge(v)) {
                PhiNode newV = peel.getDuplicatedNode((ValuePhiNode) v);
                if (newV != null) {
                    phi.setValueAt(i, newV);
                }
            }
        }
    }
    boolean progress = true;
    while (progress) {
        progress = false;
        int i = 0;
        outer: while (i < oldPhis.size()) {
            PhiNode oldPhi = oldPhis.get(i);
            for (Node usage : oldPhi.usages()) {
                if (usage instanceof PhiNode && oldPhis.contains(usage)) {
                // Do not mark.
                } else {
                    // Mark alive by removing from delete set.
                    oldPhis.remove(i);
                    progress = true;
                    continue outer;
                }
            }
            i++;
        }
    }
    for (PhiNode deadPhi : oldPhis) {
        deadPhi.clearInputs();
    }
    for (PhiNode deadPhi : oldPhis) {
        if (deadPhi.isAlive()) {
            GraphUtil.killWithUnusedFloatingInputs(deadPhi);
        }
    }
}