move the factor divan bench into the actual directory

Author: sylvestre

Cargo.lock

@@ -280,7 +280,6 @@ members = [
   "src/uu/stdbuf/src/libstdbuf",
   "src/uucore",
   "src/uucore_procs",
-  "tests/benches/factor",
   "tests/uutests",
   # "fuzz",  # TODO
 ]

Cargo.toml

@@ -31,6 +31,7 @@ path = "src/main.rs"
 
 [dev-dependencies]
 divan = { workspace = true }
+rand = { workspace = true }
 uucore = { workspace = true, features = ["benchmark"] }
 
 [lib]

src/uu/factor/Cargo.toml

@@ -3,6 +3,8 @@
 // For the full copyright and license information, please view the LICENSE
 // file that was distributed with this source code.
 
+// spell-checker:ignore funcs
+
 use divan::{Bencher, black_box};
 use uu_factor::uumain;
 use uucore::benchmark::run_util_function;
@@ -55,6 +57,60 @@ fn factor_multiple_big_uint(bencher: Bencher) {
 }
 */
 
+#[divan::bench()]
+fn factor_table(bencher: Bencher) {
+    #[cfg(target_os = "linux")]
+    check_personality();
+
+    const INPUT_SIZE: usize = 128;
+
+    let inputs = {
+        // Deterministic RNG; use an explicitly-named RNG to guarantee stability
+        use rand::{RngCore, SeedableRng};
+        const SEED: u64 = 0xdead_bebe_ea75_cafe; // spell-checker:disable-line
+        let mut rng = rand::rngs::StdRng::seed_from_u64(SEED);
+
+        std::iter::repeat_with(move || {
+            let mut array = [0u64; INPUT_SIZE];
+            for item in &mut array {
+                *item = rng.next_u64();
+            }
+            array
+        })
+        .take(10)
+        .collect::<Vec<_>>()
+    };
+
+    bencher.bench(|| {
+        for a in &inputs {
+            for n in a {
+                divan::black_box(num_prime::nt_funcs::factors(*n, None));
+            }
+        }
+    });
+}
+
+#[cfg(target_os = "linux")]
+fn check_personality() {
+    use std::fs;
+    const ADDR_NO_RANDOMIZE: u64 = 0x0040000;
+    const PERSONALITY_PATH: &str = "/proc/self/personality";
+
+    let p_string = fs::read_to_string(PERSONALITY_PATH)
+        .unwrap_or_else(|_| panic!("Couldn't read '{PERSONALITY_PATH}'"))
+        .strip_suffix('\n')
+        .unwrap()
+        .to_owned();
+
+    let personality = u64::from_str_radix(&p_string, 16)
+        .unwrap_or_else(|_| panic!("Expected a hex value for personality, got '{p_string:?}'"));
+    if personality & ADDR_NO_RANDOMIZE == 0 {
+        eprintln!(
+            "WARNING: Benchmarking with ASLR enabled (personality is {personality:x}), results might not be reproducible."
+        );
+    }
+}
+
 fn main() {
     divan::main();
 }