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Mojo module

smem_types

Shared memory type aliases for LayoutTensor-based GPU kernels.

This module defines the core SMEM type aliases used across SM90, SM100, and other GPU kernel implementations. They depend only on layout and stdlib, making them safe to import without pulling in higher-level kernel packages.

Types:

• SMemTile: Shared memory tile (LayoutTensor alias)
• RegTile: Register tile (LayoutTensor alias)
• SMemBarrier: Pointer to shared memory barrier
• PipelineBarrier: Array of pipeline barriers
• SMemTileIter: Iterator over shared memory tiles
• SMemTileArray: Array of shared memory tiles
• SMemArray: Generic shared memory array
• SMemPtr: Typed pointer into shared memory
• eval: Compile-time expression evaluator

comptime values

eval

comptime eval[T: AnyType, //, val: T] = val

Helper alias to force evaluation of expressions at compile time.

Parameters

• ​T (AnyType):
• ​val (T):

PipelineBarrier

comptime PipelineBarrier[num_pipeline_stages: Int] = SMemArray[SharedMemBarrier, num_pipeline_stages]

Type alias for shared memory pipeline barrier array.

Parameters

• ​num_pipeline_stages (Int):

RegTile

comptime RegTile[_dtype: DType, layout: Layout, /, *, element_layout: Layout = Layout(IntTuple(Int(1)), IntTuple(Int(1))), layout_int_type: DType = _get_layout_type(layout, AddressSpace.LOCAL), linear_idx_type: DType = _get_index_type(layout, AddressSpace.LOCAL), masked: Bool = False, alignment: Int = align_of[_dtype]()] = LayoutTensor[_dtype, layout, MutAnyOrigin, address_space=AddressSpace.LOCAL, element_layout=element_layout, layout_int_type=layout_int_type, linear_idx_type=linear_idx_type, masked=masked, alignment=alignment]

Type alias for register (local memory) tile tensors.

Parameters

• ​_dtype (DType):
• ​layout (Layout):
• ​element_layout (Layout):
• ​layout_int_type (DType):
• ​linear_idx_type (DType):
• ​masked (Bool):
• ​alignment (Int):

SMemBarrier

comptime SMemBarrier[origin: MutOrigin] = Pointer[SharedMemBarrier, origin, address_space=AddressSpace.SHARED]

Type alias for shared memory barrier pointer.

Parameters

• ​origin (MutOrigin):

SMemPtr

comptime SMemPtr[type: AnyType] = Pointer[type, MutUntrackedOrigin, address_space=AddressSpace.SHARED]

Parameters

• ​type (AnyType):

SMemTile

comptime SMemTile[_dtype: DType, layout: Layout, /, *, element_layout: Layout = Layout(IntTuple(Int(1)), IntTuple(Int(1))), layout_int_type: DType = _get_layout_type(layout, AddressSpace.SHARED), linear_idx_type: DType = _get_index_type(layout, AddressSpace.SHARED), masked: Bool = False, alignment: Int = align_of[_dtype]()] = LayoutTensor[_dtype, layout, MutAnyOrigin, address_space=AddressSpace.SHARED, element_layout=element_layout, layout_int_type=layout_int_type, linear_idx_type=linear_idx_type, masked=masked, alignment=alignment]

Type alias for shared memory tile tensors.

Parameters

• ​_dtype (DType):
• ​layout (Layout):
• ​element_layout (Layout):
• ​layout_int_type (DType):
• ​linear_idx_type (DType):
• ​masked (Bool):
• ​alignment (Int):

SMemTileIter

comptime SMemTileIter[dtype: DType, layout: Layout] = LayoutTensorIter[dtype, layout, MutAnyOrigin, address_space=AddressSpace.SHARED, alignment=Int(128)]

Parameters

• ​dtype (DType):
• ​layout (Layout):

Structs

• ​SMemArray: Shared memory array of fixed size.
• ​SMemTileArray: Array of tiles in shared memory.

Functions

• ​reg_tile_to_tile_tensor: Return a TileTensor view of a register tile.