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Mojo struct

SMemEpilogueWriter

@register_passable(trivial) struct SMemEpilogueWriter[c_type: DType, c_smem_layout: Layout, num_output_stages: Int, //, epilogue_dtype: DType, BM: Int, BN: Int, MMA_M: Int, MMA_N: Int, cta_group: Int, num_output_warps: Int, c_swizzle: TensorMapSwizzle, transpose_c: Bool, is_lower_frag_required: Bool, num_stages: Int, simd_size: Int, stage: Int, rep_frag_size: Int, compute_lambda_fn: elementwise_compute_lambda_type]

Write accumulator tile to SMEM and apply element-wise epilogue lambda.

This writer handles the SMEM-based epilogue path when register_based_epilogue=False. Inferred from c_tiles: c_type, c_smem_layout, num_output_stages. Derived from layout: stageN, stage_contiguous_size.

Fields

  • warp_id (UInt32):
  • c_tiles (SMemEpilogueWriter[epilogue_dtype, BM, BN, MMA_M, MMA_N, cta_group, num_output_warps, c_swizzle, transpose_c, is_lower_frag_required, num_stages, simd_size, stage, rep_frag_size, compute_lambda_fn].CTileArray):
  • M (UInt32):
  • N (UInt32):
  • c_row (UInt32):
  • c_col (UInt32):

Implemented traits

AnyType, Copyable, ImplicitlyCopyable, Movable, UnknownDestructibility

comptime members

__copyinit__is_trivial

comptime __copyinit__is_trivial = True

__del__is_trivial

comptime __del__is_trivial = True

__moveinit__is_trivial

comptime __moveinit__is_trivial = True

barrier_threads

comptime barrier_threads = (num_output_warps * WARP_SIZE)

CTileArray

comptime CTileArray = SMemTileArrayType[c_type, c_smem_layout, num_output_stages, 128]

data_paths

comptime data_paths = 16

N_dim

comptime N_dim = 0 if transpose_c else 1

stage_contiguous_size

comptime stage_contiguous_size = c_smem_layout.shape[1].value()

stageN

comptime stageN = c_smem_layout.shape[SMemEpilogueWriter[epilogue_dtype, BM, BN, MMA_M, MMA_N, cta_group, num_output_warps, c_swizzle, transpose_c, is_lower_frag_required, num_stages, simd_size, stage, rep_frag_size, compute_lambda_fn].N_dim].value()

swizzle

comptime swizzle = make_swizzle[c_type, c_swizzle]()

swizzle_width

comptime swizzle_width = (c_swizzle.bytes() // size_of[c_type]())

Tile

comptime Tile = AccumTile[epilogue_dtype, rep_frag_size]

Methods

__init__

__init__(warp_id: UInt32, c_tiles: SMemTileArrayType[c_type, c_smem_layout, num_output_stages, 128], c_shape: Tuple[UInt32, UInt32], c_coord: Tuple[UInt32, UInt32]) -> Self

Initialize the SMEM epilogue writer.

write_tile

write_tile(self, tile: AccumTile[epilogue_dtype, rep_frag_size])

Write accumulator tile to SMEM and apply epilogue lambda.

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