definitions/simd-loop/loop_113.json

{
  "name": "loop_113",
  "op_type": "loop_113",
  "description": "Sum adjacent uint32 pairs across an array (horizontal pairwise add)",
  "tags": [
    "simd-loop"
  ],
  "axes": {
    "N": {
      "type": "var",
      "description": "Array length"
    }
  },
  "inputs": {
    "a0": {
      "shape": [
        "N"
      ],
      "dtype": "int32"
    },
    "b0": {
      "shape": [
        "N"
      ],
      "dtype": "int32"
    }
  },
  "outputs": {
    "c0": {
      "shape": [
        "N"
      ],
      "dtype": "uint32",
      "description": "Output array"
    }
  },
  "reference": "import numpy as np\n\ndef run(a0, b0):\n    n = len(a0)\n    ap = np.concatenate([a0.astype(np.int32), np.zeros(2, np.int32)])\n    bp = np.concatenate([b0.astype(np.int32), np.zeros(2, np.int32)])\n    n_pairs = (n + 1) // 2\n    even = np.arange(n_pairs) * 2\n    c = np.zeros(n, dtype=np.int32)\n    # c[2k] = a[2k]+a[2k+1]\n    c_ev = (ap[even].astype(np.int64) + ap[even + 1].astype(np.int64)).astype(np.int32)\n    valid_ev = even[even < n]\n    c[valid_ev] = c_ev[:len(valid_ev)]\n    # c[2k+1] = b[2k]+b[2k+1]\n    c_od = (bp[even].astype(np.int64) + bp[even + 1].astype(np.int64)).astype(np.int32)\n    odd = even + 1\n    valid_od = odd[odd < n]\n    c[valid_od] = c_od[:len(valid_od)]\n    return c\n",
  "simd_loop_meta": {
    "output_inplace": false,
    "array_pad": 2,
    "scratch": []
  }
}