[Test, Tools] (tools/trace_replay): give the retrace harness a SPLIT variant whose output and artifact directories carry the variant too, and assert the transport resolved - a pull library under MOBILEGL_TRANSPORT=inproc replays OpenRA at ssim 1.000, so the picture cannot be the gate

tools/trace_replay/trace_cases.py

@@ -36,6 +36,23 @@ def load_trace_case_manifest(path=TRACE_CASES_JSON):
             raise ValueError(
                 f"{name} is marked verify but excluded from CI, so the verify matrix would drop it"
             )
+        # "split" opts a case into the MOBILEGL_TRANSPORT=inproc retrace subset, the same shape
+        # and the same reason as "verify" above: a typo has to be a loud manifest error in every
+        # consumer, not a subset that is quietly one case short. The split arm additionally runs
+        # DirectGLES ONLY - the server the arm exercises is Espryt's - so a case that excluded
+        # DirectGLES from CI would leave the split matrix with nothing to run.
+        split = merged.get("split", False)
+        if not isinstance(split, bool):
+            raise ValueError(f"split must be true or false for {name}")
+        if split and not merged.get("ci", True):
+            raise ValueError(
+                f"{name} is marked split but excluded from CI, so the split matrix would drop it"
+            )
+        if split and "DirectGLES" not in ci_backends(merged):
+            raise ValueError(
+                f"{name} is marked split but does not run DirectGLES in CI; the split arm is "
+                f"DirectGLES-only, so the entry would be registered with no backend"
+            )
         cases.append(merged)
     return {"defaults": defaults, "cases": cases}
 
@@ -92,6 +109,16 @@ def verify_trace_cases(cases):
     return [case for case in cases if case.get("verify", False)]
 
 
+def split_trace_cases(cases):
+    """The subset the split (MOBILEGL_TRANSPORT=inproc) CI mode retraces.
+
+    P5's phase gate names exactly one: OpenRA, at SSIM >= 0.99. It is also the only fixture that
+    is hydrated locally, so keeping the subset explicit in the manifest is what stops a later
+    phase from widening the arm into an LFS fetch by accident.
+    """
+    return [case for case in cases if case.get("split", False)]
+
+
 def ci_backends(case):
     backends = case.get("ci_backends")
     if backends is None:
@@ -122,6 +149,16 @@ def github_verify_matrix(cases):
     return github_test_matrix(verify_trace_cases(cases))
 
 
+def github_split_matrix(cases):
+    """{backend, case} for the split arm. DirectGLES only - see split_trace_cases."""
+    return {
+        "include": [
+            {"backend": "DirectGLES", "case": case["name"]}
+            for case in split_trace_cases(cases)
+        ]
+    }
+
+
 def github_apk_matrix(cases):
     backends = {
         "DirectGLES": {"name": "DirectGLES", "gpu": "software"},
@@ -158,8 +195,8 @@ def emit_cmake(cases, fixture_root):
         ("CROP_HEIGHT", "crop_height", False),
         ("COHERENT_AS_FLUSH", "coherent_as_flush", False),
     ]
-    for case in cases:
-        lines.append(f"add_trace_replay_test_for_backends({cmake_quote(case['name'])}")
+    def emit_one(function, case):
+        lines.append(f"{function}({cmake_quote(case['name'])}")
         for cmake_key, json_key, fixture_path in keys:
             value = case.get(json_key)
             if value is None or value == "":
@@ -169,6 +206,14 @@ def emit_cmake(cases, fixture_root):
             lines.append(f"        {cmake_key} {cmake_quote(value)}")
         lines.append(")")
         lines.append("")
+
+    for case in cases:
+        emit_one("add_trace_replay_test_for_backends", case)
+        # P5's split arm, emitted beside the monolith pair rather than in a block of its own so
+        # that a case and its variant always carry identical parameters. The CMake side is a
+        # no-op unless MOBILEGL_BUILD_DISAGGREGATED is ON.
+        if case.get("split", False):
+            emit_one("add_trace_replay_split_test", case)
     return "\n".join(lines)
 
 
@@ -183,6 +228,7 @@ def parse_args():
             "names",
             "github-test-matrix",
             "github-verify-matrix",
+            "github-split-matrix",
             "github-apk",
             "github-apk-matrix",
             "fixture-files",
@@ -204,6 +250,8 @@ def main():
         print(json.dumps(github_test_matrix(cases), separators=(",", ":")))
     elif args.format == "github-verify-matrix":
         print(json.dumps(github_verify_matrix(cases), separators=(",", ":")))
+    elif args.format == "github-split-matrix":
+        print(json.dumps(github_split_matrix(cases), separators=(",", ":")))
     elif args.format == "github-apk":
         print(json.dumps([github_apk_case(case) for case in cases], separators=(",", ":")))
     elif args.format == "github-apk-matrix":