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1732ed7da3
Fixes https://github.com/NVIDIA/cutlass/issues/3268 A `@cute.struct` instance captured into an `scf.if` branch or `scf.while` body fails the DSL trace with: DSLRuntimeError: The 'if' statement encountered a user-defined Python object, which cannot be automatically converted into an dynamic expression. This blocks the natural warp-specialization pattern, where each `if warp_idx == <role>:` branch reads its tile from a shared storage struct. A struct instance is fully described by its `base` pointer (already DynamicExpression-aware via `_Pointer`); every field instance is re-derived from `base + static offsets` on construction. Implement the DynamicExpression protocol on each decorated class by forwarding `__get_mlir_types__` / `__extract_mlir_values__` to `base`, and `__new_from_mlir_values__` to a fresh decorator invocation that re-derives the fields from a rebuilt base pointer. Tested in Docker on cutlass-dsl 4.5.1 with six new unit tests in test/python/CuTeDSL/test_struct_in_if.py covering: * the original failing case (storage.get_tensor inside dynamic if), * regression: plain non-branched struct usage still works, * nested struct (struct-of-struct) inside a dynamic if, * if/else with both branches accessing the struct, * if/elif/elif/else (the actual warp-specialization shape), * scf.while body capturing the struct.