third_party/skia/resources/sksl/folding/ArrayFolding.sksl

uniform half4 colorRed, colorGreen;

int globalValue = 0;

noinline int side_effecting(int value) {
    globalValue++;
    return value;
}

bool test() {
    const int x [3] = int[3](1, 2, 3);
    const int xx[3] = int[3](1, 2, 3);
    const int y [3] = int[3](1, 2, 4);

    const int z = x[0] - y[0];
    const int a [x[z]]       = int[1](1);
    const int b [x[x[z]]]    = int[2](1, 2);
    const int c [x[x[x[z]]]] = int[3](1, 2, 3);

    // Arrays with elements lacking side-effects can be optimized.
    int two = 2;
    int flatten0 = (int[3](x[0], two, 3))[0];
    int flatten1 = (int[3](x[0], two, 3))[1];
    int flatten2 = (int[3](x[0], two, 3))[2];

    // Arrays with elements that have side-effects are not eligible for optimization.
    int noFlatten0 = (int[3](--two, side_effecting(2), 3))[0];
    int noFlatten1 = (int[3](side_effecting(1), 2, 3))[1];
    int noFlatten2 = (int[3](1, ++two, 3))[2];

    return (x == xx) && !(x != xx) && (x != y) && !(x == y) &&
           (x[0] == y[0]) && (c == x) &&
           (flatten0 == noFlatten0) && (flatten1 == noFlatten1) && (flatten2 == noFlatten2);
}

half4 main(float2 coords) {
    return test() ? colorGreen : colorRed;
}