{
 "cells": [
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "ExecuteTime": {
     "end_time": "2019-03-17T20:28:08.969898Z",
     "start_time": "2019-03-17T20:28:08.963947Z"
    }
   },
   "outputs": [],
   "source": [
    "def setidx(i):\n",
    "    ''' in: int\n",
    "    out: 5bit set index (str)'''\n",
    "    b = '{0:016b}'.format(i)\n",
    "    return(b[-10:-5])\n",
    "def tag(i):\n",
    "    ''' in: int\n",
    "    out: 6bit tag '''\n",
    "    b = '{0:016b}'.format(i)\n",
    "    return(b[-16:-10])"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "ExecuteTime": {
     "end_time": "2019-03-17T20:28:09.336349Z",
     "start_time": "2019-03-17T20:28:09.331364Z"
    }
   },
   "outputs": [],
   "source": [
    "def runs(arr):\n",
    "    hit_count = 0\n",
    "    for i in range(0, 512, 4):\n",
    "        st = [] # set index list\n",
    "        d2 = {} # hist of set idxs per start idx\n",
    "        for item in arr:\n",
    "            val = setidx(item + i)\n",
    "            st.append(val)\n",
    "            try:\n",
    "                d2[val] += 1\n",
    "            except:\n",
    "                d2[val] = 1\n",
    "        if min(d2.values()) == 1: # for some starting address, we get hits\n",
    "            hit_count += 1\n",
    "    print(hit_count / (512 / 4)) # ratio of starting addrs w/ hit"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "ExecuteTime": {
     "end_time": "2019-03-17T20:28:09.756222Z",
     "start_time": "2019-03-17T20:28:09.749208Z"
    }
   },
   "outputs": [],
   "source": [
    "runs([i * 256 * 4 for i in range(4)]) # stride = 256"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "ExecuteTime": {
     "end_time": "2019-03-17T20:28:10.608852Z",
     "start_time": "2019-03-17T20:28:10.604830Z"
    }
   },
   "outputs": [],
   "source": [
    "runs([i * 255 * 4 for i in range(5)]) # stride = 255"
   ]
  }
 ],
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