TTRI

Instruction Diagram

Introduction

Generates a triangular (lower/upper) mask tile.

Mathematical Semantics

Assume R = dst.GetValidRow(), C = dst.GetValidCol(), and d = diagonal.

The lower triangular (isUpperOrLower=0) conceptually produces:

The upper triangular (isUpperOrLower=1) conceptually produces:

Assembly Syntax

AS Level 1 (SSA)

%dst = pto.ttri %diag : i32 -> !pto.tile<...>

AS Level 2 (DPS)

pto.ttri ins(%diag : i32) outs(%dst : !pto.tile_buf<...>)

C++ Built-in APIs

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 <typename TileData, int isUpperOrLower, typename... WaitEvents>
PTO_INST RecordEvent TTRI(TileData &dst, int diagonal, WaitEvents &... events);

Constraints

• isUpperOrLower must be 0 (lower triangular) or 1 (upper triangular).
• Implementation check (Atlas A2/A3 training products/Atlas A2/A3 inference products):
  • The destination tile must be row-major (isRowMajor), enforced by static_assert.
  • Supported element types: int32_t, int, int16_t, uint32_t, uint16_t, half, float16_t, float, float32_t.
• Implementation check (Ascend 950PR/Ascend 950DT):
  • Supported element types: int32_t, int16_t, int8_t, uint32_t, uint16_t, uint8_t, half, float16_t, float32_t, bfloat16_t.
  • The lower triangular (upperOrLower == 0) and upper triangular (upperOrLower == 1) cases are distinguished by if constexpr branches.
• The valid region is obtained through dst.GetValidRow()/dst.GetValidCol().

Examples

#include <pto/pto-inst.hpp>

using namespace pto;

void example_lower() {
  using TileT = Tile<TileType::Vec, float, 16, 16>;
  TileT dst;
  TASSIGN(dst, 0x1000);
  TTRI<0>(dst, /*diagonal=*/0);   // Lower triangular
}

void example_upper() {
  using TileT = Tile<TileType::Vec, float, 16, 16>;
  TileT dst;
  TASSIGN(dst, 0x1000);
  TTRI<1>(dst, /*diagonal=*/-1);  // Upper triangular
}

ASM Examples

Automatic Mode

# Automatic mode: the compiler/runtime handles resource placement and scheduling.
%dst = pto.ttri {isUpperOrLower = 0} : i32 -> !pto.tile<...>

Manual Mode

# Manual mode: explicitly bind resources first, then issue the instruction.
# pto.tassign %arg0, @tile(0x1000)
%dst = pto.ttri %diag : i32 -> !pto.tile<...>

PTO Assembly Form

%dst = pto.ttri %diag : i32 -> !pto.tile<...>
# AS Level 2 (DPS)
pto.ttri ins(%diag : i32) outs(%dst : !pto.tile_buf<...>)