<!DOCTYPE html><!-- webkit-test-runner [ IPCTestingAPIEnabled=true ] -->
<p>This test passes if an FEComponentTransfer with an empty Table/Discrete tableValues sent over IPC with FilterRenderingMode::Accelerated does not cause the CoreImage Metal kernel to read past the bounds of its table buffer.</p>
<pre id="log"></pre>
<script>
testRunner?.dumpAsText();
testRunner?.waitUntilDone();

let finished = false;
function done(s) {
    if (finished)
        return;
    finished = true;
    document.getElementById('log').textContent = s;
    testRunner?.notifyDone();
}
let nextID = 100000; function genID() { return nextID++; }

setTimeout(async () => {
    if (!window.IPC)
        return done('PASS');
    try {
        const { CoreIPC } = await import('./coreipc.js');

        // std::optional<CoreIPCCGColorSpace> needs its bool discriminator exposed.
        CoreIPC.typeInfo['WebCore::PlatformColorSpace'] = [
            { type: 'std::optional<WebKit::CoreIPCCGColorSpace>', name: 'alias' }
        ];
        // Look the ColorSpace value up by name rather than hardcoding an ordinal.
        const CS = {};
        for (const e of IPC.serializedEnumInfo['WebCore::ColorSpace'].valueMap) CS[e.name] = e.value;
        const sRGB = { serializableColorSpace: { alias: { optionalValue: {
            m_cgColorSpace: { alias: { variantType: 'WebCore::ColorSpace', variant: CS.SRGB } } } } } };

        const sc = CoreIPC.newStreamConnection();
        const RBID = genID();
        CoreIPC.GPU.GPUConnectionToWebProcess.CreateRenderingBackend(0, {
            renderingBackendIdentifier: RBID,
            connectionHandle: sc
        });
        const rrb = sc.newInterface('RemoteRenderingBackend', RBID);

        function createImageBuffer(id, ctx) {
            rrb.CreateImageBuffer({
                logicalSize: { width: 32, height: 32 }, renderingMode: 1, renderingPurpose: 0,
                resolutionScale: 1.0, colorSpace: sRGB,
                bufferFormat: { pixelFormat: 2, useLosslessCompression: 0 },
                identifier: id, contextIdentifier: ctx,
            });
            // Drain the unsolicited DidCreateBackend in-turn; otherwise it reaches the stream
            // connection's dummy receiver, which ASSERT_NOT_REACHED()s in debug builds.
            sc.connection.waitForMessage(id, IPC.messages.RemoteImageBufferProxy_DidCreateBackend.name);
        }

        // Source buffer, filled opaque white.
        const SRC = genID(), SRCCTX = genID();
        createImageBuffer(SRC, SRCCTX);
        sc.newInterface('RemoteGraphicsContext', SRCCTX).FillRectWithColor({
            rect: { location: { x: 0, y: 0 }, size: { width: 32, height: 32 } },
            color: { data: { optionalValue: { isSemantic: false, usesFunctionSerialization: false,
                data: { variantType: 'WebCore::PackedColor::RGBA', variant: { value: 0xFFFFFFFF } } } } }
        });
        sc.newInterface('RemoteImageBuffer', SRC).FlushContext({});

        function ctf(type, table) {
            return { type: type, slope: 0, intercept: 0, amplitude: 0, exponent: 0, offset: 0, tableValues: table };
        }
        const sourceGraphic = { subclasses: { variantType: 'WebCore::SourceGraphic', variant: { operatingColorSpace: sRGB } } };
        const identity = ctf(1, []);
        const sentinel = 0.37;

        // Destination buffer: draw SRC through an FEComponentTransfer whose red channel has a
        // one-entry DISCRETE table (the sentinel) and whose green channel has an *empty* DISCRETE
        // table. Before the fix the CoreImage kernel indexed tableStart[-1] for the empty channel,
        // leaking the adjacent (red) table entry into green.
        const DST = genID(), DSTCTX = genID();
        createImageBuffer(DST, DSTCTX);
        sc.newInterface('RemoteGraphicsContext', DSTCTX).DrawFilteredImageBuffer({
            sourceImageIdentifier: { optionalValue: SRC },
            sourceImageRect: { location: { x: 0, y: 0 }, size: { width: 32, height: 32 } },
            filter: { subclasses: { variantType: 'WebCore::SVGFilterRenderer', variant: {
                primitiveUnits: 1,
                expression: { alias: [{ index: 0, level: 1, geometry: {} }, { index: 1, level: 0, geometry: {} }] },
                effects: [sourceGraphic,
                    { subclasses: { variantType: 'WebCore::FEComponentTransfer', variant: {
                        redFunction: ctf(3, [sentinel]), greenFunction: ctf(3, []),
                        blueFunction: identity, alphaFunction: identity,
                        operatingColorSpace: sRGB } } }],
                geometry: { referenceBox: { location: { x: 0, y: 0 }, size: { width: 32, height: 32 } },
                    filterRegion: { location: { x: 0, y: 0 }, size: { width: 32, height: 32 } },
                    scale: { width: 1, height: 1 } },
                filterRenderingModes: 3, renderingOptions: 0,
                renderingResourceIdentifierIfExists: {},
            } } },
        });
        sc.newInterface('RemoteImageBuffer', DST).FlushContext({});

        // Read the filtered result back synchronously into shared memory.
        const N = 32 * 32 * 4;
        const shm = IPC.createSharedMemory(N);
        shm.writeBytes(new Uint8Array(N).fill(0xAA));
        sc.newInterface('RemoteImageBuffer', DST).GetPixelBufferWithNewMemory({
            handle: { protection: 'ReadWrite', handle: shm },
            outputFormat: { alphaFormat: 0, pixelFormat: 0, colorSpace: sRGB },
            srcPoint: { x: 0, y: 0 }, srcSize: { width: 32, height: 32 },
        });
        const px = new Uint8Array(shm.readBytes(0, N));
        const green = px[(8 * 32 + 8) * 4 + 1];

        const sentinelByte = Math.round(sentinel * 255);
        sc.connection.invalidate();
        if (Math.abs(green - sentinelByte) <= 4)
            done('FAIL: empty-table DISCRETE channel returned the adjacent table entry (green=' + green + '); kernel indexed tableStart[-1]');
        else
            done('PASS');
    } catch (e) {
        done('PASS');
    }
}, 0);

setTimeout(() => done('PASS'), 25000);
</script>