[QST] [CuTeDSL] Alignment dropped by partition_S.

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Here is the code of my vectorized transposed kernel, it fails to compile with the error:

cutlass.base_dsl.common.DSLRuntimeError: DSLRuntimeError: 🧊🧊🧊 ICE IR Verification Failed 🧊🧊🧊
  Caused exception: Verification failed:
error: "cute.copy("("/home/brain_l/flashtree/base/cutedsl_kernel/src/transpose.py":41:4): 'cute.copy' op '!cute_nvgpu.atom.universal_copy<f32, 128 b>' ptr alignment does not meet requirement
 note: "cute.copy("("/home/brain_l/flashtree/base/cutedsl_kernel/src/transpose.py":41:4): see current operation: "cute.copy"(%arg3, %149, %161) : (!cute.tiled_copy<!cute_nvgpu.atom.universal_copy<f32, 128 b>, layout_copy_tv = <"((8,32),4):((128,1),32)">, tiler_mn = <"[32:1;32:1]">>, !cute.memref<f32, gmem, "((4,1),(1,1)):((1,0),(0,0))">, !cute.memref<f32, smem, align<16>, "((4,1),(1,1)):((1,0),(0,0))">) -> ()

I tried to print the iterator with cute.printf(g2s_thr_src.iterator), it shows align to 4 bytes. But the raw ptr value is aligned to 16 bytes. My guess is the alignment is not propogated correctly and is dropped by partition_S, how should I do this correctly?

raw_ptr(0x00007fbeac604c00: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604c10: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604c20: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604c30: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604c40: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604c50: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604c60: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604c70: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604d00: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604d10: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604d20: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604d30: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604d40: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604d50: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604d60: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604d70: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604e00: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604e10: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604e20: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604e30: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604e40: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604e50: f32, gmem, align<4>)
raw_ptr(0x00007fbeac604e60: f32, gmem, align<4>)

Start with the linked gist and the transpose.py:41:4 cute.copy call, then trace how g2s_thr_src.iterator is produced through partition_S. Compare the iterator's reported align<4> metadata with the raw pointer addresses and the 128-bit copy requirement. Done means determining whether partition_S drops valid alignment information and documenting or correcting the propagation path.