Quartus multi out with stream fix

[calad0i]

A# Description

Quartus writer writes uncompilable programs when there are multiple outputs with io_stream. This PR fixes that.

Type of change

• Bug fix (non-breaking change that fixes an issue)

Tests

test/pytest/test_multiout_network.py

Test Configuration:

Checklist

• I have read the guidelines for contributing.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• I have installed and run pre-commit on the files I edited or added.
• I have added tests that prove my fix is effective or that my feature works.

[jmitrevs]

Does this work correctly if the multiple outputs have a different type? I am worried that they get forced to result_t, though I didn't check.

[jmitrevs]

It is these lines that make me concerned about the output types when there are multiple outputs:
https://github.com/fastmachinelearning/hls4ml/blob/main/hls4ml/model/graph.py#L472-L477
https://github.com/fastmachinelearning/hls4ml/blob/main/hls4ml/model/graph.py#L610-L613

[vloncar]

@jmitrevs Those lines were also problematic in our attempts to split the writing into multiple IPs. There's no practical reason for this feature to exist, it is merely to be human readable from the very ancient times, and in my (limited) tests everything still works if they are removed

[jmitrevs]

I just tried:

def test_multi_clone(model, data, backend: str, io_type: str):
    output_dir = str(test_root_path / f'hls4mlprj_multiout_network_{backend}_{io_type}')
    hls_config = config_from_keras_model(model, "name", default_precision='fixed<32,5>')
    hls_config["LayerName"]["dense_linear"]["Precision"]["result"] = 'fixed<35,5>'
    hls_config["LayerName"]["dense_1_linear"]["Precision"]["result"] = 'fixed<40,5>'
    hls_config["LayerName"]["dense"]["Precision"]["result"] = 'fixed<35,5>'
    hls_config["LayerName"]["dense_1"]["Precision"]["result"] = 'fixed<40,5>'
    model_hls = convert_from_keras_model(
        model, backend=backend, output_dir=output_dir, hls_config=hls_config, io_type=io_type
    )
    model_hls.compile()
    r_hls = model_hls.predict(data)
    r_keras = [x.numpy() for x in model(data)]

    assert np.allclose(r_hls[0], r_keras[0], atol=1e-5, rtol=0)
    assert np.allclose(r_hls[1], r_keras[1], atol=1e-5, rtol=0)

and both outputs are result_t of fixed<35,5>. I could have made a mistake in the test code (and I am not sure why I had to define the linear result like that, too), but the behavior doesn't seem quire right.

[calad0i]

I changed the two places in graph.py, and now the output variables are not overwriting each other. It does not seem to affect other tests in my tests. Though, maybe this should go into a separate PR.

[jmitrevs]

There is still some manual seeding left, if I looked at the code correctly.

[jmitrevs]

@calad0i, can you remove the remaining seed setting?

Actually, let me run pytests first again. So hold off on the merge.

[jmitrevs]

Generally other that the test_root_path issue, I think this is good. After that is fixed we can merge it.