TGATHERB¶

指令示意图¶

简介¶

使用字节偏移量收集元素。

数学语义¶

对每个元素 在有效区域内：

Exact bounds behavior is implementation-defined.

汇编语法¶

PTO-AS 形式：参见 PTO-AS Specification.

同步形式：

%dst = tgatherb %src, %offsets : !pto.tile<...> -> !pto.tile<...>

AS Level 1 (SSA)¶

%dst = pto.tgatherb %src, %offsets : (!pto.tile<...>, !pto.tile<...>) -> !pto.tile<...>

AS Level 2 (DPS)¶

pto.tgatherb ins(%src, %offsets : !pto.tile_buf<...>, !pto.tile_buf<...>) outs(%dst : !pto.tile_buf<...>)

AS Level 1（SSA）¶

%dst = pto.tgatherb %src, %offsets : (!pto.tile<...>, !pto.tile<...>) -> !pto.tile<...>

AS Level 2（DPS）¶

pto.tgatherb ins(%src, %offsets : !pto.tile_buf<...>, !pto.tile_buf<...>) outs(%dst : !pto.tile_buf<...>)

C++ 内建接口¶

声明于 include/pto/common/pto_instr.hpp:

template <typename TileDataDst, typename TileDataSrc, typename TileDataOffset, typename... WaitEvents>
PTO_INST RecordEvent TGATHERB(TileDataDst &dst, TileDataSrc &src, TileDataOffset &offset, WaitEvents &... events);

约束¶

• 实现检查 (A2A3):
  • Destination layout must be row-major (TileDataDst::isRowMajor).
  • Destination element size must be 1, 2, or 4 bytes (enforced via static_assert in the helper).
  • SrcTileData::DType/DstTileData::DType must be int8_t or uint8_t or int16_t or uint16_t or int32_t or uint32_t or half or bfloat16_t or float.
• 实现检查 (A5):
  • Destination element size must be 1, 2, or 4 bytes.
  • SrcTileData::DType/DstTileData::DType must be int8_t or uint8_t or int16_t or uint16_t or int32_t or uint32_t or half or bfloat16_t or float.
• Offset interpretation:
  • Offsets are interpreted as uint32_t values (byte offsets) by the implementation.
  • Offset bounds are not validated by explicit runtime assertions; out-of-range offsets are target-defined.

示例¶

自动（Auto）¶

#include <pto/pto-inst.hpp>

using namespace pto;

void example_auto() {
  using SrcT = Tile<TileType::Vec, uint8_t, 1, 256>;
  using OffT = Tile<TileType::Vec, uint32_t, 1, 256>;
  using DstT = Tile<TileType::Vec, uint8_t, 1, 256>;
  SrcT src;
  OffT off;
  DstT dst;
  TGATHERB(dst, src, off);
}

手动（Manual）¶

#include <pto/pto-inst.hpp>

using namespace pto;

void example_manual() {
  using SrcT = Tile<TileType::Vec, uint8_t, 1, 256>;
  using OffT = Tile<TileType::Vec, uint32_t, 1, 256>;
  using DstT = Tile<TileType::Vec, uint8_t, 1, 256>;
  SrcT src;
  OffT off;
  DstT dst;
  TASSIGN(src, 0x1000);
  TASSIGN(off, 0x2000);
  TASSIGN(dst, 0x3000);
  TGATHERB(dst, src, off);
}