[Model] Optimize CosyVoice3 packed streaming with bounded HiFT graphs (#8420)

Signed-off-by: Sy03 <1370724210@qq.com>

tests/model_executor/models/cosyvoice3/test_cosyvoice3_hift_graph.py

@@ -0,0 +1,41 @@
+# SPDX-License-Identifier: Apache-2.0
+# SPDX-FileCopyrightText: Copyright contributors to the vLLM-Omni project
+"""HiFT graphs consume live inputs and return independently owned waveforms."""
+
+import pytest
+import torch
+
+from tests.helpers.mark import hardware_test
+from tests.model_executor.models.cosyvoice3.test_cosyvoice3_incremental_hift import _make_hift
+
+pytestmark = [pytest.mark.core_model]
+
+
+@hardware_test(res={"cuda": "L4"}, num_cards=1)
+@pytest.mark.parametrize("finalize", [False, True])
+@torch.inference_mode()
+def test_hift_graph_preserves_current_and_previous_request(finalize):
+    hift = _make_hift().cuda().eval()
+    hift.remove_weight_norm()
+    hift.f0_predictor.remove_weight_norm()
+    hift.enable_decode_graphs()
+    generator = torch.Generator(device="cuda").manual_seed(17)
+    saved: list[tuple[torch.Tensor, torch.Tensor]] = []
+    for _ in range(5):
+        mel = torch.randn(1, 80, 30, device="cuda", generator=generator)
+        source = torch.randn(1, 1, 30 * 480, device="cuda", generator=generator)
+        expected = hift._decode_eager(mel, source, finalize=finalize)
+        actual = hift.decode(mel, source, finalize=finalize)
+        torch.testing.assert_close(actual, expected, rtol=1e-5, atol=1e-6)
+        for previous, snapshot in saved:
+            assert torch.equal(previous, snapshot)
+        if hift._decode_graphs.graphs:
+            saved.append((actual, actual.clone()))
+    assert len(hift._decode_graphs.graphs) == 1
+    hift._decode_graphs.max_graphs = 1
+    mel = torch.randn(1, 80, 31, device="cuda", generator=generator)
+    source = torch.randn(1, 1, 31 * 480, device="cuda", generator=generator)
+    actual = hift.decode(mel, source, finalize=finalize)
+    expected = hift._decode_eager(mel, source, finalize=finalize)
+    assert torch.equal(actual, expected)
+    assert len(hift._decode_graphs.graphs) == 1