skia2/resources/sksl/shared/SwizzleByIndex.sksl

void non_constant_swizzle() {
    int4 i = int4(int(sqrt(1)));
    half4 v = half4(half(sqrt(1)));
    half x = v[i[0]];
    half y = v[i[1]];
    half z = v[i[2]];
    half w = v[i[3]];
    sk_FragColor = half4(x, y, z, w);
}

void constant_swizzle() {
    half4 v = half4(half(sqrt(1)));
    half x = v[0];
    half y = v[1];
    half z = v[2];
    half w = v[3];
    sk_FragColor = half4(x, y, z, w);
}

void foldable() {
    half4 v = half4(2);
    half x = v[0];
    half y = v[1];
    half z = v[2];
    half w = v[3];
    sk_FragColor = half4(x, y, z, w);
}

void main() {
    non_constant_swizzle();
    constant_swizzle();
    foldable();
}