Polymorphic AST eval

Interface / virtual-method dispatch through nine AST node types under heavy traversal load.

Runtime Compile time

Runtime · median per inner-loop window

median of 10 runs

Native Gocompiled

2.11 ms0.04×

Piko interpbytecode VM

54.9 msbaseline

CPython 3.13bytecode VM

55.7 ms1.01×

PyPy 7.3tracing JIT

80.1 ms1.46×

Ttengobytecode VM

120 ms2.18×

Sscriggobytecode VM

unsupported in scriggo

n/a

Mmvmbytecode VM

246 ms4.49×

YyaegiAST walker

1.40 s25.5×

Full statistics

Runner	N	Compile	Runtime	P95	Stddev	RSS	vs piko	Status
Native Gocompiled	10	181 ms	2.11 ms	2.13 ms	12.0 µs	69 MiB	0.04×	OK
Piko interpbytecode VM	10	2.03 ms	54.9 ms	55.4 ms	309 µs	131 MiB	1.00×	OK
CPython 3.13bytecode VM	10	620 µs	55.7 ms	57.5 ms	1.25 ms	n/a	1.01×	OK
PyPy 7.3tracing JIT	10	482 µs	80.1 ms	83.5 ms	1.19 ms	n/a	1.46×	OK
tengobytecode VM	10	373 µs	120 ms	123 ms	1.19 ms	200 MiB	2.18×	OK
scriggobytecode VM	0	n/a	n/a	n/a	n/a	n/a	n/a	unsupported
mvmbytecode VM	10	687 µs	246 ms	275 ms	20.0 ms	67 MiB	4.49×	OK
yaegiAST walker	10	702 µs	1.40 s	1.53 s	49.4 ms	71 MiB	25.5×	OK

Workload & symmetry rules

Workload

Build an expression tree from a deterministic LCG that mixes nine node kinds (Add, Sub, Mul, Mod, Const, Var, IfPos, Min, Max), each as a distinct struct/class satisfying a single-method contract: Node.Eval(env) uint32. Walk the tree repeatedly and accumulate the fold.

Symmetry rules

Real interface dispatch in Go (Eval(env) method on a Node interface) and class-based duck typing in Python.
No tagged-union switch shortcut; every Eval call must go through dynamic dispatch.

Why this benchmark exists

A direct measurement of the interpreter's interface / virtual-method dispatch path. Bench 05 is similar but uses a tagged-int switch; this one forces real virtual dispatch.

Source code

piko / Go
piko_source.go
native Go
native_main.go
CPython / PyPy
cpython.py
tengo
script.tengo