pto.tlrelu

pto.tlrelu is part of the Tile Scalar And Immediate instruction set.

Summary

Leaky ReLU with a scalar slope.

Mechanism

Leaky ReLU with a scalar slope. It operates on tile payloads rather than scalar control state, and its legality is constrained by tile shape, layout, valid-region, and target-profile support.

For each element (i, j) in the valid region:

\[ \mathrm{dst}_{i,j} = (\mathrm{src}_{i,j} > 0) ? \mathrm{src}_{i,j} : (\mathrm{src}_{i,j} \cdot \mathrm{slope}) \]

Syntax

Textual spelling is defined by the PTO ISA syntax-and-operands pages.

Synchronous form:

%dst = tlrelu %src, %slope : !pto.tile<...>, f32

AS Level 1 (SSA)

%dst = pto.tlrelu %src, %scalar : (!pto.tile<...>, dtype) -> !pto.tile<...>

AS Level 2 (DPS)

pto.tlrelu ins(%src, %scalar : !pto.tile_buf<...>, dtype) outs(%dst : !pto.tile_buf<...>)

C++ Intrinsic

Declared in include/pto/common/pto_instr.hpp:

template <typename TileDataDst, typename TileDataSrc, typename... WaitEvents>
PTO_INST RecordEvent TLRELU(TileDataDst& dst, TileDataSrc& src, typename TileDataSrc::DType scalar, WaitEvents&... events);

Inputs

  • src is the source tile.
  • slope is the scalar slope for negative values (broadcast to all lanes).
  • dst names the destination tile.
  • The operation iterates over dst's valid region.

Expected Outputs

dst carries the result tile or updated tile payload produced by the operation.

Side Effects

No architectural side effects beyond producing the destination tile. Does not implicitly fence unrelated traffic.

Constraints

Constraints

  • Common constraints:

    • Tile location must be vector (TileData::Loc == TileType::Vec).
    • Static valid bounds: TileData::ValidRow <= TileData::Rows and TileData::ValidCol <= TileData::Cols.
    • Runtime: dst and src must have the same valid row/col.
    • Slope scalar type must match the Tile data type.

  • Valid region:

    • The op uses dst.GetValidRow() / dst.GetValidCol() as the iteration domain.

Exceptions

Exceptions

  • Illegal operand tuples, unsupported types, invalid layout combinations, or unsupported target-profile modes are rejected by the verifier or by the selected backend instruction set.
  • Programs must not rely on behavior outside the documented legal domain of this operation, even if one backend currently accepts it.

Target-Profile Restrictions

Target-Profile Restrictions

  • Implementation checks (A2A3):

    • TileData::DType must be one of: half, float16_t, float, float32_t (floating-point types only).
    • Tile layout must be row-major (TileData::isRowMajor).

  • Implementation checks (A5):

    • TileData::DType must be one of: half, float (floating-point types only).
    • Tile layout must be row-major (TileData::isRowMajor).

Examples

#include <pto/pto-inst.hpp>

using namespace pto;

void example() {
  using TileT = Tile<TileType::Vec, float, 16, 16>;
  TileT x, out;
  TLRELU(out, x, 0.1f);
}

Auto Mode

# Auto mode: compiler/runtime-managed placement and scheduling.
%dst = pto.tlrelu %src, %scalar : (!pto.tile<...>, dtype) -> !pto.tile<...>

Manual Mode

# Manual mode: bind resources explicitly before issuing the instruction.
# Optional for tile operands:
# pto.tassign %arg0, @tile(0x1000)
# pto.tassign %arg1, @tile(0x2000)
%dst = pto.tlrelu %src, %scalar : (!pto.tile<...>, dtype) -> !pto.tile<...>

PTO Assembly Form

%dst = tlrelu %src, %slope : !pto.tile<...>, f32
# AS Level 2 (DPS)
pto.tlrelu ins(%src, %scalar : !pto.tile_buf<...>, dtype) outs(%dst : !pto.tile_buf<...>)