pto.tpartmul

pto.tpartmul is part of the Irregular And Complex instruction set.

Summary

Partial elementwise multiply with handling of mismatched valid regions. On A2/A3 and A5, when only one input is valid at an element, the result copies that input value; on the CPU simulator, the same behavior applies.

Mechanism

Performs elementwise multiplication over the destination valid region. When both src0 and src1 are valid at an element, the result is their product; when only one input is valid there, the result copies that input value. On A2/A3 and A5, when neither input is valid at an element, the result is undefined; on the CPU simulator, the same behavior applies. It belongs to the tile instructions and carries architecture-visible behavior that is not reducible to a plain elementwise compute pattern.

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

\[ \mathrm{dst}_{i,j} = \begin{cases} \mathrm{src0}_{i,j} \cdot \mathrm{src1}_{i,j} & \text{if both inputs are defined at } (i,j) \\ \mathrm{src0}_{i,j} & \text{if only src0 is defined at } (i,j) \\ \mathrm{src1}_{i,j} & \text{if only src1 is defined at } (i,j) \end{cases} \]

Syntax

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

Synchronous form:

%dst = tpartmul %src0, %src1 : !pto.tile<...> -> !pto.tile<...>

AS Level 1 (SSA)

%dst = pto.tpartmul %src0, %src1 : !pto.tile<...> -> !pto.tile<...>

AS Level 2 (DPS)

pto.tpartmul ins(%src0, %src1 : !pto.tile_buf<...>) outs(%dst : !pto.tile_buf<...>)

IR Level 1 (SSA)

%dst = pto.tpartmul %src0, %src1 : !pto.tile<...> -> !pto.tile<...>

IR Level 2 (DPS)

pto.tpartmul ins(%src0, %src1 : !pto.tile_buf<...>) outs(%dst : !pto.tile_buf<...>)

C++ Intrinsic

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

template <typename TileDataDst, typename TileDataSrc0, typename TileDataSrc1, typename... WaitEvents>
PTO_INST RecordEvent TPARTMUL(TileDataDst &dst, TileDataSrc0 &src0, TileDataSrc1 &src1, WaitEvents &... events);

Inputs

  • src0 is the first source tile.
  • src1 is the second source tile.
  • dst names the destination tile. The operation iterates over dst's valid region.

Expected Outputs

dst holds the elementwise partial product: both valid gives product; one valid gives the valid value.

Side Effects

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

Constraints

Constraints

General constraints / checks

  • dst, src0, and src1 must use the same element type.

  • The destination valid region defines the result domain.

  • For each element in the destination valid region:

  • if both inputs are valid, the instruction applies its elementwise operator;

  • if only one input is valid, the result copies that input value.

  • If dst has a zero valid region, the instruction returns early.

  • Supported partial-validity patterns require at least one source tile to have a valid region exactly equal to dst, while the other source tile's valid region must not exceed dst in either dimension.

  • Supported element types: int32_t, int16_t, half, float.

  • Supported element types: uint8_t, int8_t, uint16_t, int16_t, uint32_t, int32_t, half, float, bfloat16_t.

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
  • On A2/A3 and A5, handling of validity patterns not explicitly listed above results in undefined behavior; on the CPU simulator, the same behavior applies.
  • dst, src0, and src1 must all be row-major (isRowMajor).

No additional restriction is documented for this target.

Examples

Auto

#include <pto/pto-inst.hpp>
using namespace pto;

void example_auto() {
  using TileT = Tile<TileType::Vec, float, 16, 16>;
  TileT src0, src1, dst;
  TPARTMUL(dst, src0, src1);
}

Manual

#include <pto/pto-inst.hpp>
using namespace pto;

void example_manual() {
  using TileT = Tile<TileType::Vec, float, 16, 16>;
  TileT src0, src1, dst;
  TASSIGN(src0, 0x1000);
  TASSIGN(src1, 0x2000);
  TASSIGN(dst,  0x3000);
  TPARTMUL(dst, src0, src1);
}

Auto Mode

# Auto mode: compiler/runtime-managed placement and scheduling.
%dst = pto.tpartmul %src0, %src1 : !pto.tile<...> -> !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.tpartmul %src0, %src1 : !pto.tile<...> -> !pto.tile<...>

PTO Assembly Form

%dst = tpartmul %src0, %src1 : !pto.tile<...> -> !pto.tile<...>
# AS Level 2 (DPS)
pto.tpartmul ins(%src0, %src1 : !pto.tile_buf<...>) outs(%dst : !pto.tile_buf<...>)