ghc_timings: Introduce it

README.md

@@ -43,6 +43,7 @@ the scripts are available using `nix-shell`.
    profiler.
  * `eventlog-sort`: A hack to dump the events from a GHC eventlog with relative
    timestamps (in milliseconds).
+ * `ghc_timings.py`: A small hack to turn `-ddump-timings` output into a Markdown table.
 
 
 ## Release engineering

ghc_timings.py

+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+
+import re
+import sys
+import typing
+from typing import Iterator
+
+class Timing(typing.NamedTuple):
+    phase: str
+    module: str
+    time: float
+    allocd: float
+
+def parse_timings(s: str) -> Iterator[Timing]:
+    for m in re.finditer(r'!!! ([\w \d]+) \[([\w\d_\.]+)\]: finished in (\d+\.\d+) milliseconds, allocated (\d+\.\d+) megabytes', s):
+        phase = m.group(1)
+        module = m.group(2)
+        time = float(m.group(3))
+        allocd = float(m.group(4))
+        yield Timing(phase, module, time, allocd)
+
+def main() -> None:
+    s = sys.stdin.read()
+    print('| module | phase | time (ms) | alloc (MB) |')
+    print('| ------ | ----- | --------- | ---------- |')
+    for t in parse_timings(s):
+        print('| {module} | {phase} | {time} | {allocd} |'.format(**t))
+
+if __name__ == '__main__':
+    main()