TRESHAPE

Tile Operation Diagram

Introduction

Reinterpret a tile as another tile type/shape while preserving the underlying bytes.

This is a bitwise reshape: it does not change values, it only changes how the same byte buffer is viewed.

Assembly Syntax

%dst = treshape %src : !pto.tile<...>

AS Level 1 (SSA)

%dst = pto.treshape %src : !pto.tile<...> -> !pto.tile<...>

AS Level 2 (DPS)

pto.treshape ins(%src : !pto.tile_buf<...>) outs(%dst : !pto.tile_buf<...>)

C++ Intrinsic

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

template <typename TileDataOut, typename TileDataIn, typename... WaitEvents>
PTO_INST RecordEvent TRESHAPE(TileDataOut &dst, TileDataIn &src, WaitEvents &... events);

Constraints

Enforced by TRESHAPE_IMPL:

• Tile type must match: TileDataIn::Loc == TileDataOut::Loc.
• Total byte size must match: sizeof(InElem) * InNumel == sizeof(OutElem) * OutNumel.
• No boxed/non-boxed conversion:
  • cannot reshape between SLayout::NoneBox and boxed layouts.

Notes

• CPU simulation: implemented as a byte-for-byte copy into dst.
• A2/A3: implemented as an alias (TASSIGN_IMPL(dst, src.data())), so dst and src refer to the same underlying storage.

Examples

#include <pto/pto-inst.hpp>

using namespace pto;

void example() {
  using Src = Tile<TileType::Vec, float, 16, 16>;
  using Dst = Tile<TileType::Vec, float, 8, 32>;
  static_assert(Src::Numel == Dst::Numel);

  Src src;
  Dst dst;
  TRESHAPE(dst, src);
}

Math Interpretation

Unless otherwise specified, semantics are defined over the valid region and target-dependent behavior is marked as implementation-defined.

ASM Form Examples

Auto Mode

# Auto mode: compiler/runtime-managed placement and scheduling.
%dst = pto.treshape %src : !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)
%dst = pto.treshape %src : !pto.tile<...> -> !pto.tile<...>

PTO Assembly Form

%dst = pto.treshape %src : !pto.tile<...> -> !pto.tile<...>
# AS Level 2 (DPS)
pto.treshape ins(%src : !pto.tile_buf<...>) outs(%dst : !pto.tile_buf<...>)