test: make wide int benchmark more stable

Author: KRRT7

Tools/scripts/bench_wide_int_pyperf.py

@@ -1,37 +1,70 @@
 """Microbenchmark compact vs wide int add/sub with pyperf.
 
-Use this with PYTHON_JIT=0 and -S if you want a stable interpreter-only run:
+Use this with PYTHON_JIT=0 for a stable interpreter-only run:
 
-    PYTHON_JIT=0 ./python.exe -S Tools/scripts/bench_wide_int_pyperf.py
+    PYTHON_JIT=0 ./python.exe Tools/scripts/bench_wide_int_pyperf.py
 """
 
 from __future__ import annotations
 
 import pyperf
 
+_BATCH = 10_000
+_sink = 0
 
-def bench_add_compact() -> int:
-    a = 1
-    b = 2
-    return a + b
 
+def _bench_add(a: int, b: int) -> None:
+    global _sink
+    x = 0
+    for _ in range(_BATCH):
+        x = a + b
+    _sink = x
 
-def bench_add_wide() -> int:
-    a = 10_000_000_000
-    b = 1
-    return a + b
 
+def _bench_sub(a: int, b: int) -> None:
+    global _sink
+    x = 0
+    for _ in range(_BATCH):
+        x = a - b
+    _sink = x
 
-def bench_sub_compact() -> int:
-    a = 1
-    b = 2
-    return a - b
 
+def bench_add_compact() -> None:
+    _bench_add(1, 2)
 
-def bench_sub_wide() -> int:
-    a = 10_000_000_000
-    b = 1
-    return a - b
+
+def bench_add_wide() -> None:
+    _bench_add(1 << 40, 1)
+
+
+def bench_sub_compact() -> None:
+    _bench_sub(1, 2)
+
+
+def bench_sub_wide() -> None:
+    _bench_sub(1 << 40, 1)
+
+
+def bench_chain_compact() -> None:
+    global _sink
+    total = 0
+    a = 2000
+    b = 3
+    c = 4000
+    for _ in range(_BATCH):
+        total += a * b + c
+    _sink = total
+
+
+def bench_chain_wide() -> None:
+    global _sink
+    total = 0
+    a = 1 << 40
+    b = 3
+    c = 1 << 20
+    for _ in range(_BATCH):
+        total += a * b + c
+    _sink = total
 
 
 def main() -> None:
@@ -40,6 +73,8 @@ def main() -> None:
     runner.bench_func("add_wide", bench_add_wide)
     runner.bench_func("sub_compact", bench_sub_compact)
     runner.bench_func("sub_wide", bench_sub_wide)
+    runner.bench_func("chain_compact", bench_chain_compact)
+    runner.bench_func("chain_wide", bench_chain_wide)
 
 
 if __name__ == "__main__":