TRANDOM

Tile Operation Diagram

Introduction

Generates random numbers in the destination tile using a counter-based cryptographic algorithm.

Mathematical Semantics

This instruction implements a counter-based random number generator. For each element in the valid region, it generates a pseudo-random value based on the key and counter state, using a cipher-like transformation with a configurable number of rounds.

The algorithm uses:

• A 128-bit state (4 × 32-bit counters)
• A 64-bit key (2 × 32-bit words)
• ChaCha-like quarter-round operations using vector instructions

Assembly Syntax

Synchronous form:

trandom %dst, %key, %counter : !pto.tile<...>

AS Level 1 (SSA)

%dst = pto.trandom %key, %counter : (!pto.tile<...>, !pto.tile<...>) -> !pto.tile<...>

AS Level 2 (DPS)

pto.trandom ins(%key, %counter : !pto.tile_buf<...>, !pto.tile_buf<...>) outs(%dst : !pto.tile_buf<...>)

C++ Built-in Functions

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

The public include header is <pto/pto-inst.hpp>, and the internal declaration is located in pto/common/pto_instr.hpp.

template <uint16_t Rounds = 10, typename DstTile, typename... WaitEvents>
PTO_INST RecordEvent TRANDOM(DstTile &dst, TRandomKey &key, TRandomCounter &counter, WaitEvents &... events);

Constraints

• Implementation check (Ascend 950PR/Ascend 950DT):
  • DstTile::DType must be one of the following types: int32_t, uint32_t.
  • The tile layout must be row-major (DstTile::isRowMajor).
  • Rounds must be 7 or 10 (defaults to 10).
  • key and counter cannot be empty.
• Valid region:
  • This operation uses dst.GetValidRow()/dst.GetValidCol() as the iteration domain.

Examples

Automatic Mode

#include <pto/pto-inst.hpp>

using namespace pto;

void example_auto() {
  using TileT = Tile<TileType::Vec, uint32_t, 16, 16>;
  TileT dst;
  TRandomKey key = {0x01234, 0x56789};
  TRandomCounter counter = {0, 0, 0, 0};
  TRANDOM(dst, key, counter);
}

Manual Mode

#include <pto/pto-inst.hpp>

using namespace pto;

void example_manual() {
  using TileT = Tile<TileType::Vec, uint32_t, 16, 16>;
  TileT dst;
  TRandomKey key = {0x01234, 0x56789};
  TRandomCounter counter = {0, 0, 0, 0};
  TASSIGN(dst, 0x0);
  TRANDOM<10>(dst, key, counter);
}

ASM Examples

Automatic Mode

# Automatic mode: compiler/runtime-managed layout and scheduling.
%dst = pto.trandom %key, %counter : (!pto.tile<...>, !pto.tile<...>) -> !pto.tile<...>

Manual Mode

# Manual mode: explicitly bind resources before issuing the instruction.
# Tile operands are optional:
# pto.tassign %arg0, @tile(0x3000)
%dst = pto.trandom %key, %counter : (!pto.tile<...>, !pto.tile<...>) -> !pto.tile<...>

PTO Assembly Form

trandom %dst, %key, %counter : !pto.tile<...>
# AS Level 2 (DPS)
pto.trandom ins(%key, %counter : !pto.tile_buf<...>, !pto.tile_buf<...>) outs(%dst : !pto.tile_buf<...>)