#include <bits/stdc++.h>
#define rep(x, l, r) for(int x = l; x <= r; x++)
#define repd(x, r, l) for(int x = r; x >= l; x--)
#define clr(x, y) memset(x, y, sizeof(x))
using namespace std;
typedef long long ll;
const int INF = 0x3f3f3f3f;

const int MAXN = 1e6 + 5;
const int MAXM = 25;
const int mod = 1e9 + 7;

int dp[MAXN], sum[MAXN][MAXM], l[MAXN], r[MAXN];

int judge(int x, int y){
    int res = x ^ y;
    // printf("%d  %d  %d\n", x, y, res);
    repd(i, 20, 0){
        if((1 << i) & res) return i;
    }
    return -1;
}

int main(){
    int t;
    scanf("%d", &t);
    while(t--){
        int n, m;
        scanf("%d%d", &m, &n);
        int M = (1 << m) - 1;
        rep(i, 1, M) dp[i] = 0;
        rep(i, 1, n){
            rep(j, 1, m - 1) sum[i][j] = 0;
        }
        rep(i, 1, n){
            scanf("%d%d", &l[i], &r[i]);
        }
        rep(i, l[1], r[1]){
            dp[i] = i;
            int w = judge(i, r[1] + 1);
            sum[1][w] = (sum[1][w] + dp[i]) % mod;
            // printf("%d 1 : %d       %d\n", i, w, sum[1][w]);
        }
        int j = 1;
        rep(i, r[1] + 1, M){
            while(j < n && r[j] < i) j++;
            int v = judge(i, l[j]);
            // printf("%d %d : %d %d\n", i, j, v, dp[i]);
            rep(k, v + 1, 19) dp[i] = (dp[i] + sum[j - 1][k]) % mod;
            // printf("%d %d : %d %d\n", i, j, v, dp[i]);
            dp[i] = 1ll * dp[i] * i% mod;
        }
        int ans = 0;
        rep(i, l[n], r[n]) ans = (ans + dp[i]) % mod;
        printf("%d\n", ans);
    }
    return 0;
}