{
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    {
      "cell_type": "markdown",
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      "source": [
        "# The circuit inliner plugin\n",
        "\n",
        "By default, circuits constructed by the pyAQASM library have a somewhat compressed structure.\n",
        "\n",
        "Circuits consists in a main body, and each gate might have a subcircuit implementation that recursively describes the flow of the circuit.\n",
        "\n",
        "Lets consider, for instance, a QFT adder:\n"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {},
      "outputs": [],
      "source": [
        "# we define a simple function that prints the instructions in the main body of a circuit:\n",
        "def print_main(circuit):\n",
        "    from qat.core.util import extract_syntax\n",
        "    for op in circuit.ops:\n",
        "        print(extract_syntax(circuit.gateDic[op.gate], circuit.gateDic), op.qbits)\n",
        "        \n",
        "from qat.lang.AQASM import *\n",
        "from qat.lang.AQASM.qftarith import add\n",
        "\n",
        "prog = Program()\n",
        "qbits = prog.qalloc(4)\n",
        "prog.apply(add(2, 2), qbits)\n",
        "circuit = prog.to_circ()\n",
        "\n",
        "print_main(circuit)"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "This is not very explicit.\n",
        "In fact, if one iterates over the circuit, we can see that the circuit contains many more instructions:"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {
        "scrolled": true
      },
      "outputs": [],
      "source": [
        "for op in circuit.iterate_simple():\n",
        "    print(op)"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "What happened here is that the iterator `iterate_simple` emulated an execution stack when iterating over the circuit and unfolded the full circuit.\n",
        "\n",
        "Equivalently, one could simply ask the `to_circ` method to unfold all the circuit:"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {},
      "outputs": [],
      "source": [
        "circuit_full = prog.to_circ(inline=True)\n",
        "print_main(circuit)"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "`CircuitInliner` is a plugin that performs this inlining process in the stack. It should be used in case some other plugins requires an inlined circuit to run properly."
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {},
      "outputs": [],
      "source": [
        "from qat.plugins import CircuitInliner\n",
        "from qat.core import Batch\n",
        "plugin = CircuitInliner()\n",
        "print(\"==== Before 'compile'\")\n",
        "print_main(circuit)\n",
        "batch = Batch(jobs=[circuit.to_job()])\n",
        "batch = plugin.compile(batch, None)\n",
        "print(\"==== After 'compile'\")\n",
        "print_main(circuit)"
      ]
    },
    {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
        "As you can see, the circuit was modified in place. This behavior can be changed via the 'inplace' parameter:"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {},
      "outputs": [],
      "source": [
        "circuit = prog.to_circ()\n",
        "plugin = CircuitInliner(inplace=False)\n",
        "print(\"==== Before 'compile'\")\n",
        "print_main(circuit)\n",
        "batch = Batch(jobs=[circuit.to_job()])\n",
        "batch = plugin.compile(batch, None)\n",
        "print(\"==== After 'compile'\")\n",
        "print_main(circuit)\n",
        "print(\"==== output:\")\n",
        "print_main(batch.jobs[0].circuit)"
      ]
    },
    {
      "cell_type": "code",
      "execution_count": null,
      "metadata": {},
      "outputs": [],
      "source": []
    }
  ],
  "metadata": {
    "authors": [
      "Simon Martiel"
    ],
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      "language": "python",
      "name": "python3"
    },
    "language_info": {
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      "nbconvert_exporter": "python",
      "pygments_lexer": "ipython3",
      "version": "3.12.11"
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