TGEMV_MX

Tile Operation Diagram

Introduction

GEMV with scaling tiles for mixed-precision / quantized matrix-vector compute on supported targets.

This instruction family extends TGEMV with additional scale operands (mx path). Accumulator and scale handling are target-dependent.

Math Interpretation

Conceptually (base GEMV path):

$${\mathrm{C}}_{0,j}=\sum _{k=0}^{K-1}{\mathrm{A}}_{0,k}\cdot {\mathrm{B}}_{k,j}$$

For TGEMV_MX, scale tiles participate in implementation-defined mixed-precision reconstruction / scaling. The architectural contract is that output corresponds to the target-defined mx GEMV semantics.

Assembly Syntax

Schematic form:

%acc = tgemv.mx %a, %a_scale, %b, %b_scale : (!pto.tile<...>, !pto.tile<...>, !pto.tile<...>, !pto.tile<...>) -> !pto.tile<...>

AS Level 1 (SSA)

%acc = pto.tgemv.mx %a, %a_scale, %b, %b_scale : (!pto.tile<...>, !pto.tile<...>, !pto.tile<...>, !pto.tile<...>) -> !pto.tile<...>

AS Level 2 (DPS)

pto.tgemv.mx ins(%a, %a_scale, %b, %b_scale : (!pto.tile_buf<...>, !pto.tile_buf<...>, !pto.tile_buf<...>, !pto.tile_buf<...>)) outs(%acc : !pto.tile_buf<...>)

C++ Intrinsic

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

template <typename TileRes, typename TileLeft, typename TileLeftScale, typename TileRight, typename TileRightScale,
          typename... WaitEvents>
PTO_INST RecordEvent TGEMV_MX(TileRes &cMatrix, TileLeft &aMatrix, TileLeftScale &aScaleMatrix, TileRight &bMatrix, TileRightScale &bScaleMatrix, WaitEvents &... events);

template <AccPhase Phase, typename TileRes, typename TileLeft, typename TileLeftScale, typename TileRight,
          typename TileRightScale, typename... WaitEvents>
PTO_INST RecordEvent TGEMV_MX(TileRes &cMatrix, TileLeft &aMatrix, TileLeftScale &aScaleMatrix, TileRight &bMatrix, TileRightScale &bScaleMatrix, WaitEvents &... events);

template <typename TileRes, typename TileLeft, typename TileLeftScale, typename TileRight, typename TileRightScale,
          typename... WaitEvents>
PTO_INST RecordEvent TGEMV_MX(TileRes &cOutMatrix, TileRes &cInMatrix, TileLeft &aMatrix, TileLeftScale &aScaleMatrix, TileRight &bMatrix, TileRightScale &bScaleMatrix, WaitEvents &... events);

template <AccPhase Phase, typename TileRes, typename TileLeft, typename TileLeftScale, typename TileRight,
          typename TileRightScale, typename... WaitEvents>
PTO_INST RecordEvent TGEMV_MX(TileRes &cOutMatrix, TileRes &cInMatrix, TileLeft &aMatrix, TileLeftScale &aScaleMatrix, TileRight &bMatrix, TileRightScale &bScaleMatrix, WaitEvents &... events);

template <typename TileRes, typename TileLeft, typename TileLeftScale, typename TileRight, typename TileRightScale,
          typename TileBias, typename... WaitEvents>
PTO_INST RecordEvent TGEMV_MX(TileRes &cMatrix, TileLeft &aMatrix, TileLeftScale &aScaleMatrix, TileRight &bMatrix, TileRightScale &bScaleMatrix, TileBias &biasData, WaitEvents &... events);

template <AccPhase Phase, typename TileRes, typename TileLeft, typename TileLeftScale, typename TileRight,
          typename TileRightScale, typename TileBias, typename... WaitEvents>
PTO_INST RecordEvent TGEMV_MX(TileRes &cMatrix, TileLeft &aMatrix, TileLeftScale &aScaleMatrix, TileRight &bMatrix, TileRightScale &bScaleMatrix, TileBias &biasData, WaitEvents &... events);

Additional overloads support accumulation/bias variants and AccPhase selection.

Constraints

• Uses backend-specific mx legality checks for data types, tile locations, fractal/layout combinations, and scaling formats.
• Scale tile compatibility and accumulator promotion are implementation-defined by target backend.
• For portability, validate the exact (A, B, scaleA, scaleB, C) type tuple and tile layout against target implementation constraints.

Examples

For practical usage patterns, see:

• docs/isa/TMATMUL_MX.md
• docs/isa/TGEMV.md

ASM Form Examples

Auto Mode

# Auto mode: compiler/runtime-managed placement and scheduling.
%acc = pto.tgemv.mx %a, %a_scale, %b, %b_scale : (!pto.tile<...>, !pto.tile<...>, !pto.tile<...>, !pto.tile<...>) -> !pto.tile<...>

Manual Mode

# Manual mode: resources must be bound explicitly before issuing the instruction.
# Optional for tile operands:
# pto.tassign %arg0, @tile(0x1000)
# pto.tassign %arg1, @tile(0x2000)
%acc = pto.tgemv.mx %a, %a_scale, %b, %b_scale : (!pto.tile<...>, !pto.tile<...>, !pto.tile<...>, !pto.tile<...>) -> !pto.tile<...>

PTO Assembly Form

%acc = pto.tgemv.mx %a, %a_scale, %b, %b_scale : (!pto.tile<...>, !pto.tile<...>, !pto.tile<...>, !pto.tile<...>) -> !pto.tile<...>
# AS Level 2 (DPS)
pto.tgemv.mx ins(%a, %a_scale, %b, %b_scale : (!pto.tile_buf<...>, !pto.tile_buf<...>, !pto.tile_buf<...>, !pto.tile_buf<...>)) outs(%acc : !pto.tile_buf<...>)