### Compilation failed:

error: 7: unknown identifier 'packHalf2x16'
    const uint constXY = packHalf2x16(constVal.xy);
                         ^^^^^^^^^^^^
error: 8: unknown identifier 'packHalf2x16'
    const uint constZW = packHalf2x16(constVal.zw);
                         ^^^^^^^^^^^^
error: 9: unknown identifier 'packHalf2x16'
    uint xy = packHalf2x16(testInputs.xy);
              ^^^^^^^^^^^^
error: 10: unknown identifier 'packHalf2x16'
    uint zw = packHalf2x16(testInputs.zw);
              ^^^^^^^^^^^^
error: 12: unknown identifier 'unpackHalf2x16'
    return (unpackHalf2x16(xy)      == float2(expected.xy) &&
            ^^^^^^^^^^^^^^
error: 12: unknown identifier 'xy'
    return (unpackHalf2x16(xy)      == float2(expected.xy) &&
                           ^^
error: 13: unknown identifier 'unpackHalf2x16'
            unpackHalf2x16(zw)      == float2(expected.zw) &&
            ^^^^^^^^^^^^^^
error: 13: unknown identifier 'zw'
            unpackHalf2x16(zw)      == float2(expected.zw) &&
                           ^^
error: 14: unknown identifier 'unpackHalf2x16'
            unpackHalf2x16(constXY) == float2(expected.xy) &&
            ^^^^^^^^^^^^^^
error: 14: unknown identifier 'constXY'
            unpackHalf2x16(constXY) == float2(expected.xy) &&
                           ^^^^^^^
error: 15: unknown identifier 'unpackHalf2x16'
            unpackHalf2x16(constZW) == float2(expected.zw))
            ^^^^^^^^^^^^^^
error: 15: unknown identifier 'constZW'
            unpackHalf2x16(constZW) == float2(expected.zw))
                           ^^^^^^^
12 errors