# bitcompare

> **Tool `tools/verify/bitcompare.py`** (program, Verify). Compare two raw dumps value by value, bit for bit: ground truth against a port's output.

Run it with `./gameframe run bitcompare ARGS` or `python3 tools/verify/bitcompare.py`. [Source on GitHub](https://github.com/tanepiper/game-frame/blob/main/tools/verify/bitcompare.py).

## Its own help

This is the help text in the tool itself, as `./gameframe tool bitcompare` prints it.

```text
Compare two raw dumps value by value, bit for bit: ground truth against a port's output.

Usage: bitcompare.py TYPE EXPECTED.bin ACTUAL.bin [--show N]

TYPE is f32, f64, i32, u32, i16, u16 or u8. Floats are compared by their bits, so 0.0 and -0.0
differ and NaNs compare equal only when identical, which is what bit-exact means. Prints the
match count, the first N mismatches with their index (default 10) and, for floats, the largest
difference in units in the last place (ULP): 1 ULP usually means one operation in a different
order or precision; large differences mean a wrong formula or a wrong input. Exit status 1 on
any mismatch.
```

## Named by

Skills: [re-emulate](/skills/re-emulate), [re-verify](/skills/re-verify).

Agents: [re-verifier](/agents/re-verifier), [re-matcher](/agents/re-matcher).