-rw-r--r-- 2790 cryptattacktester-20230614/ram_cost.cpp raw
#include <map>
#include "bit_cost.h"
#include "ram_cost.h"

using namespace std;

static map<tuple<bigint,bigint,bigint>,bigint> ram_read_cost_cache;
static map<tuple<bigint,bigint,bigint,bool>,bigint> ram_write_cost_cache;
static map<tuple<bigint,bigint,bigint,bool>,bigint> ram_read_write_cost_cache;

bigint ram_read_cost(bigint N,bigint ibits,bigint length)
{
  if (N <= 1) return 0;

  tuple<bigint,bigint,bigint> key = make_tuple(N,ibits,length);
  if (ram_read_cost_cache.count(key))
    return ram_read_cost_cache[key];

  bigint splitpos = 0;
  bigint split = 1;
  while (2*split < N) {
    ++splitpos;
    split *= 2;
  }
  if (ibits <= splitpos)
    return ram_read_cost(split,ibits,length);
  
  bigint result = 0;
  result += ram_read_cost(split,splitpos,length);
  result += ram_read_cost(N-split,splitpos,length);
  result += length*bit_mux_cost; // result.push_back(isplit.mux(x0,x1));

  ram_read_cost_cache[key] = result;
  return result;
}

bigint ram_write_cost(bigint N,bigint ibits,bigint length,bool top)
{
  if (N <= 0) return 0;
  if (N == 1) {
    if (top)
      return 0;
    else
      return length*bit_mux_cost; // b.mux(data.at(r), x.at(L).at(r));
  }

  tuple<bigint,bigint,bigint,bool> key = make_tuple(N,ibits,length,top);
  if (ram_write_cost_cache.count(key))
    return ram_write_cost_cache[key];

  bigint splitpos = 0;
  bigint split = 1;
  while (2*split < N) {
    ++splitpos;
    split *= 2;
  }
  if (ibits <= splitpos)
    return ram_write_cost(split,ibits,length,top);
  
  bigint result = 0;
  if (top)
    result += 1; // ~isplit // XXX: suppress ~
  else
    result += 2; // b|isplit ... b.orn(isplit)
  result += ram_write_cost(split,splitpos,length,0);
  result += ram_write_cost(N-split,splitpos,length,0);

  ram_write_cost_cache[key] = result;
  return result;
}

bigint ram_read_write_cost(bigint N,bigint ibits,bigint length,bool top)
{
  if (N <= 0) return 0;
  if (N == 1) {
    if (top)
      return 0;
    else
      return length*bit_mux_cost; // bit_vector_mux(x.at(L), data, x.at(L), b);
  }

  tuple<bigint,bigint,bigint,bool> key = make_tuple(N,ibits,length,top);
  if (ram_read_write_cost_cache.count(key))
    return ram_read_write_cost_cache[key];

  bigint splitpos = 0;
  bigint split = 1;
  while (2*split < N) {
    ++splitpos;
    split *= 2;
  }
  if (ibits <= splitpos)
    return ram_read_write_cost(split,ibits,length,top);
  
  bigint result = 0;
  if (top)
    result += 1; // ~isplit // XXX: suppress ~
  else
    result += 2; // b|isplit ... b.orn(isplit)
  result += ram_read_write_cost(split,splitpos,length,0);
  result += ram_read_write_cost(N-split,splitpos,length,0);
  result += length*bit_mux_cost; // result.push_back(isplit.mux(x0,x1));

  ram_read_write_cost_cache[key] = result;
  return result;
}