zig-dimal/src/benchmark.zig
2026-04-22 00:00:18 +02:00

473 lines
22 KiB
Zig

const std = @import("std");
const tracy = @import("ztracy");
const Io = std.Io;
const Scalar = @import("Scalar.zig").Scalar;
const Vector = @import("Vector.zig").Vector;
var io: Io = undefined;
pub fn main(init: std.process.Init) !void {
var stdout_buf: [4096]u8 = undefined;
var stdout_writer: std.Io.File.Writer = .init(.stdout(), init.io, &stdout_buf);
try stdout_writer.interface.print("Starting Benchmarks...", .{});
io = init.io;
try bench_Scalar(&stdout_writer.interface);
try stdout_writer.flush();
try bench_vsNative(&stdout_writer.interface);
try stdout_writer.flush();
try bench_crossTypeVsNative(&stdout_writer.interface);
try stdout_writer.flush();
try bench_Vector(&stdout_writer.interface);
try stdout_writer.flush();
}
fn getTime() Io.Timestamp {
return Io.Clock.awake.now(io);
}
fn fold(comptime TT: type, s: *f64, v: TT) void {
s.* += if (comptime @typeInfo(TT) == .float)
@as(f64, @floatCast(v))
else
@as(f64, @floatFromInt(v));
}
fn bench_Scalar(writer: *std.Io.Writer) !void {
const ITERS: usize = 100_000;
const SAMPLES: usize = 10;
var gsink: f64 = 0;
const getVal = struct {
fn f(comptime TT: type, i: usize, comptime mask: u7) TT {
const v: u8 = @as(u8, @truncate(i & @as(usize, mask))) + 1;
return if (comptime @typeInfo(TT) == .float) @floatFromInt(v) else @intCast(v);
}
}.f;
const Stats = struct {
median: f64,
delta: f64,
ops_per_sec: f64,
};
const computeStats = struct {
fn f(samples: []f64, iters: usize) Stats {
std.mem.sort(f64, samples, {}, std.sort.asc(f64));
const mid = samples.len / 2;
const median_ns = if (samples.len % 2 == 0) (samples[mid - 1] + samples[mid]) / 2.0 else samples[mid];
const low = samples[0];
const high = samples[samples.len - 1];
const delta_ns = (high - low) / 2.0;
const ns_per_op = median_ns / @as(f64, @floatFromInt(iters));
return .{
.median = ns_per_op,
.delta = (delta_ns / @as(f64, @floatFromInt(iters))),
.ops_per_sec = 1_000_000_000.0 / ns_per_op,
};
}
}.f;
try writer.print(
\\
\\ Scalar<T> benchmark — {d} iterations, {d} samples/cell
\\
\\┌───────────────────┬──────┬─────────────────────┬─────────────────────┐
\\│ Operation │ Type │ ns / op (± delta) │ Throughput (ops/s) │
\\├───────────────────┼──────┼─────────────────────┼─────────────────────┤
\\
, .{ ITERS, SAMPLES });
const Types = .{ i16, i32, i64, i128, i256, f32, f64, f128 };
const TNames = .{ "i16", "i32", "i64", "i128", "i256", "f32", "f64", "f128" };
const Ops = .{ "add", "sub", "mulBy", "divBy", "scale", "to" };
var results_matrix: [Ops.len][Types.len]f64 = undefined;
comptime var tidx: usize = 0;
inline for (Types, TNames) |T, tname| {
const M = Scalar(T, .init(.{ .L = 1 }), .init(.{}));
const KM = Scalar(T, .init(.{ .L = 1 }), .init(.{ .L = .k }));
const S = Scalar(T, .init(.{ .T = 1 }), .init(.{}));
inline for (Ops, 0..) |op_name, oidx| {
var samples: [SAMPLES]f64 = undefined;
for (0..SAMPLES) |s_idx| {
var sink: T = 0;
const t_start = getTime();
for (0..ITERS) |i| {
const r = if (comptime std.mem.eql(u8, op_name, "add"))
(M{ .value = getVal(T, i, 63) }).add(M{ .value = getVal(T, i +% 7, 63) })
else if (comptime std.mem.eql(u8, op_name, "sub"))
(M{ .value = getVal(T, i +% 10, 63) }).sub(M{ .value = getVal(T, i, 63) })
else if (comptime std.mem.eql(u8, op_name, "mulBy"))
(M{ .value = getVal(T, i, 63) }).mulBy(M{ .value = getVal(T, i +% 1, 63) })
else if (comptime std.mem.eql(u8, op_name, "divBy"))
(M{ .value = getVal(T, i +% 10, 63) }).divBy(S{ .value = getVal(T, i, 63) })
else if (comptime std.mem.eql(u8, op_name, "scale"))
(M{ .value = getVal(T, i, 63) }).scale(getVal(T, i +% 2, 63))
else
(KM{ .value = getVal(T, i, 15) }).to(M);
if (comptime @typeInfo(T) == .float) sink += r.value else sink ^= r.value;
}
const t_end = getTime();
samples[s_idx] = @as(f64, @floatFromInt(t_start.durationTo(t_end).toNanoseconds()));
fold(T, &gsink, sink);
}
const stats = computeStats(&samples, ITERS);
results_matrix[oidx][tidx] = stats.median;
try writer.print("│ {s:<17} │ {s:<4} │ {d:>8.2} ns ±{d:<6.2} │ {d:>19.0} │\n", .{ op_name, tname, stats.median, stats.delta, stats.ops_per_sec });
}
if (comptime tidx < Types.len - 1) {
try writer.print("├───────────────────┼──────┼─────────────────────┼─────────────────────┤\n", .{});
}
tidx += 1;
}
// Median Summary Table
try writer.print("└───────────────────┴──────┴─────────────────────┴─────────────────────┘\n\n", .{});
try writer.print("Median Summary (ns/op):\n", .{});
try writer.print("┌──────────────┬───────┬───────┬───────┬───────┬───────┬───────┬───────┬───────┐\n", .{});
try writer.print("│ Operation │ i16 │ i32 │ i64 │ i128 │ i256 │ f32 │ f64 │ f128 │\n", .{});
try writer.print("├──────────────┼───────┼───────┼───────┼───────┼───────┼───────┼───────┼───────┤\n", .{});
inline for (Ops, 0..) |op_name, oidx| {
try writer.print("│ {s:<11} │", .{op_name});
var i: usize = 0;
while (i < Types.len) : (i += 1)
try writer.print("{d:>6.1} │", .{results_matrix[oidx][i]});
try writer.print("\n", .{});
}
try writer.print("└──────────────┴───────┴───────┴───────┴───────┴───────┴───────┴───────┴───────┘\n", .{});
try writer.print("\nAnti-optimisation sink: {d:.4}\n", .{gsink});
try std.testing.expect(gsink != 0);
}
fn bench_vsNative(writer: *std.Io.Writer) !void {
const ITERS: usize = 100_000;
const SAMPLES: usize = 5;
// Helper to safely get a value of type T from a loop index
const getValT = struct {
fn f(comptime TT: type, i: usize) TT {
const v = (i % 100) + 1;
return if (comptime @typeInfo(TT) == .float) @floatFromInt(v) else @intCast(v);
}
}.f;
const Types = .{ i32, i64, i128, f32, f64 };
const TNames = .{ "i32", "i64", "i128", "f32", "f64" };
const Ops = .{ "add", "mulBy", "divBy" };
var gsink: f64 = 0;
try writer.print(
\\
\\ Scalar vs Native Overhead Analysis
\\
\\┌───────────┬──────┬───────────┬───────────┬───────────┐
\\│ Operation │ Type │ Native │ Scalar │ Slowdown │
\\├───────────┼──────┼───────────┼───────────┼───────────┤
\\
, .{});
inline for (Ops, 0..) |op_name, j| {
inline for (Types, 0..) |T, tidx| {
var native_total_ns: f64 = 0;
var quantity_total_ns: f64 = 0;
const M = Scalar(T, .init(.{ .L = 1 }), .init(.{}));
const S = Scalar(T, .init(.{ .T = 1 }), .init(.{}));
for (0..SAMPLES) |_| {
// --- 1. Benchmark Native ---
var n_sink: T = 0;
const n_start = getTime();
for (0..ITERS) |i| {
const a = getValT(T, i);
const b = getValT(T, 2);
const r = if (comptime std.mem.eql(u8, op_name, "add"))
a + b
else if (comptime std.mem.eql(u8, op_name, "mulBy"))
a * b
else if (comptime @typeInfo(T) == .int) @divTrunc(a, b) else a / b;
if (comptime @typeInfo(T) == .float) n_sink += r else n_sink ^= r;
}
const n_end = getTime();
native_total_ns += @as(f64, @floatFromInt(n_start.durationTo(n_end).toNanoseconds()));
fold(T, &gsink, n_sink);
// --- 2. Benchmark Scalar ---
var q_sink: T = 0;
const q_start = getTime();
for (0..ITERS) |i| {
const qa = M{ .value = getValT(T, i) };
const qb = if (comptime std.mem.eql(u8, op_name, "divBy")) S{ .value = getValT(T, 2) } else M{ .value = getValT(T, 2) };
const r = if (comptime std.mem.eql(u8, op_name, "add"))
qa.add(qb)
else if (comptime std.mem.eql(u8, op_name, "mulBy"))
qa.mulBy(qb)
else
qa.divBy(qb);
if (comptime @typeInfo(T) == .float) q_sink += r.value else q_sink ^= r.value;
}
const q_end = getTime();
quantity_total_ns += @as(f64, @floatFromInt(q_start.durationTo(q_end).toNanoseconds()));
fold(T, &gsink, q_sink);
}
const avg_n = (native_total_ns / SAMPLES) / @as(f64, @floatFromInt(ITERS));
const avg_q = (quantity_total_ns / SAMPLES) / @as(f64, @floatFromInt(ITERS));
const slowdown = avg_q / avg_n;
try writer.print("│ {s:<9} │ {s:<4} │ {d:>7.2}ns │ {d:>7.2}ns │ {d:>8.2}x │\n", .{
op_name, TNames[tidx], avg_n, avg_q, slowdown,
});
}
if (j != Ops.len - 1) try writer.print("├───────────┼──────┼───────────┼───────────┼───────────┤\n", .{});
}
try writer.print("└───────────┴──────┴───────────┴───────────┴───────────┘\n", .{});
try writer.print("\nAnti-optimisation sink: {d:.4}\n", .{gsink});
try std.testing.expect(gsink != 0);
}
fn bench_crossTypeVsNative(writer: *std.Io.Writer) !void {
const ITERS: usize = 100_000;
const SAMPLES: usize = 5;
const getValT = struct {
fn f(comptime TT: type, i: usize) TT {
// Keep values safe and non-zero to avoid division by zero or overflows during cross-casting
const v = (i % 50) + 1;
return if (comptime @typeInfo(TT) == .float) @floatFromInt(v) else @intCast(v);
}
}.f;
// Helper for the Native baseline: explicitly casting T2 to T1 before the operation
const castTo = struct {
fn f(comptime DestT: type, comptime SrcT: type, val: SrcT) DestT {
if (comptime DestT == SrcT) return val;
const src_info = @typeInfo(SrcT);
const dest_info = @typeInfo(DestT);
if (dest_info == .int and src_info == .int) return @intCast(val);
if (dest_info == .float and src_info == .int) return @floatFromInt(val);
if (dest_info == .int and src_info == .float) return @intFromFloat(val);
if (dest_info == .float and src_info == .float) return @floatCast(val);
unreachable;
}
}.f;
const Types = .{ i16, i64, i128, f32, f64 };
const TNames = .{ "i16", "i64", "i128", "f32", "f64" };
const Ops = .{ "add", "mulBy", "divBy" };
var gsink: f64 = 0;
try writer.print(
\\
\\ Cross-Type Overhead Analysis: Scalar vs Native
\\
\\┌─────────┬──────┬──────┬───────────┬───────────┬───────────┐
\\│ Op │ T1 │ T2 │ Native │ Scalar │ Slowdown │
\\├─────────┼──────┼──────┼───────────┼───────────┼───────────┤
\\
, .{});
inline for (Ops, 0..) |op_name, j| {
inline for (Types, 0..) |T1, t1_idx| {
inline for (Types, 0..) |T2, t2_idx| {
var native_total_ns: f64 = 0;
var quantity_total_ns: f64 = 0;
const M1 = Scalar(T1, .init(.{ .L = 1 }), .init(.{}));
const M2 = Scalar(T2, .init(.{ .L = 1 }), .init(.{}));
const S2 = Scalar(T2, .init(.{ .T = 1 }), .init(.{}));
for (0..SAMPLES) |_| {
// --- 1. Benchmark Native (Cast T2 to T1, then math) ---
var n_sink: T1 = 0;
const n_start = getTime();
for (0..ITERS) |i| {
const a = getValT(T1, i);
const b_raw = getValT(T2, 2);
const b = castTo(T1, T2, b_raw);
const r = if (comptime std.mem.eql(u8, op_name, "add"))
a + b
else if (comptime std.mem.eql(u8, op_name, "mulBy"))
a * b
else if (comptime @typeInfo(T1) == .int)
@divTrunc(a, b)
else
a / b;
if (comptime @typeInfo(T1) == .float) n_sink += r else n_sink ^= r;
}
const n_end = getTime();
native_total_ns += @as(f64, @floatFromInt(n_start.durationTo(n_end).toNanoseconds()));
fold(T1, &gsink, n_sink);
// --- 2. Benchmark Scalar ---
var q_sink: T1 = 0;
const q_start = getTime();
for (0..ITERS) |i| {
const qa = M1{ .value = getValT(T1, i) };
const qb = if (comptime std.mem.eql(u8, op_name, "divBy"))
S2{ .value = getValT(T2, 2) }
else
M2{ .value = getValT(T2, 2) };
const r = if (comptime std.mem.eql(u8, op_name, "add"))
qa.add(qb)
else if (comptime std.mem.eql(u8, op_name, "mulBy"))
qa.mulBy(qb)
else
qa.divBy(qb);
if (comptime @typeInfo(T1) == .float) q_sink += r.value else q_sink ^= r.value;
}
const q_end = getTime();
quantity_total_ns += @as(f64, @floatFromInt(q_start.durationTo(q_end).toNanoseconds()));
fold(T1, &gsink, q_sink);
}
const avg_n = (native_total_ns / SAMPLES) / @as(f64, @floatFromInt(ITERS));
const avg_q = (quantity_total_ns / SAMPLES) / @as(f64, @floatFromInt(ITERS));
const slowdown = avg_q / avg_n;
try writer.print("│ {s:<7} │ {s:<4} │ {s:<4} │ {d:>7.2}ns │ {d:>7.2}ns │ {d:>8.2}x │\n", .{
op_name, TNames[t1_idx], TNames[t2_idx], avg_n, avg_q, slowdown,
});
}
}
if (j != Ops.len - 1) {
try writer.print("├─────────┼──────┼──────┼───────────┼───────────┼───────────┤\n", .{});
}
}
try writer.print("└─────────┴──────┴──────┴───────────┴───────────┴───────────┘\n", .{});
try writer.print("\nAnti-optimisation sink: {d:.4}\n", .{gsink});
try std.testing.expect(gsink != 0);
}
fn bench_Vector(writer: *std.Io.Writer) !void {
const ITERS: usize = 10_000;
const SAMPLES: usize = 10;
var gsink: f64 = 0;
const getVal = struct {
fn f(comptime TT: type, i: usize, comptime mask: u7) TT {
const v: u8 = @as(u8, @truncate(i & @as(usize, mask))) + 1;
return if (comptime @typeInfo(TT) == .float) @floatFromInt(v) else @intCast(v);
}
}.f;
const computeStats = struct {
fn f(samples: []f64, iters: usize) f64 {
std.mem.sort(f64, samples, {}, std.sort.asc(f64));
const mid = samples.len / 2;
const median_ns = if (samples.len % 2 == 0)
(samples[mid - 1] + samples[mid]) / 2.0
else
samples[mid];
return median_ns / @as(f64, @floatFromInt(iters));
}
}.f;
try writer.print(
\\
\\ Vector<N, T> benchmark — {d} iterations, {d} samples/cell
\\ (Results in ns/op)
\\
\\┌─────────────┬──────┬─────────┬─────────┬─────────┐
\\│ Operation │ Type │ Len=3 │ Len=4 │ Len=16 │
\\├─────────────┼──────┼─────────┼─────────┼─────────┤
\\
, .{ ITERS, SAMPLES });
const Types = .{ i32, i64, i128, f32, f64 };
const TNames = .{ "i32", "i64", "i128", "f32", "f64" };
const Lengths = .{ 3, 4, 16 };
const Ops = .{ "add", "scale", "mulByScalar", "length" };
inline for (Ops, 0..) |op_name, o_idx| {
inline for (Types, TNames) |T, tname| {
try writer.print("│ {s:<11} │ {s:<4} │", .{ op_name, tname });
inline for (Lengths) |len| {
const Q_base = Scalar(T, .init(.{ .L = 1 }), .init(.{}));
const Q_time = Scalar(T, .init(.{ .T = 1 }), .init(.{}));
const V = Vector(len, Q_base);
var samples: [SAMPLES]f64 = undefined;
for (0..SAMPLES) |s_idx| {
var sink: T = 0;
const t_start = getTime();
for (0..ITERS) |i| {
const v1 = V.initDefault(getVal(T, i, 63));
if (comptime std.mem.eql(u8, op_name, "add")) {
const v2 = V.initDefault(getVal(T, i +% 7, 63));
const res = v1.add(v2);
for (res.data) |val| {
if (comptime @typeInfo(T) == .float) sink += val else sink ^= val;
}
} else if (comptime std.mem.eql(u8, op_name, "scale")) {
const sc = getVal(T, i +% 2, 63);
const res = v1.scale(sc);
for (res.data) |val| {
if (comptime @typeInfo(T) == .float) sink += val else sink ^= val;
}
} else if (comptime std.mem.eql(u8, op_name, "mulByScalar")) {
const s_val = Q_time{ .value = getVal(T, i +% 2, 63) };
const res = v1.mulByScalar(s_val);
for (res.data) |val| {
if (comptime @typeInfo(T) == .float) sink += val else sink ^= val;
}
} else if (comptime std.mem.eql(u8, op_name, "length")) {
const r = v1.length();
if (comptime @typeInfo(T) == .float) sink += r else sink ^= r;
}
}
const t_end = getTime();
samples[s_idx] = @as(f64, @floatFromInt(t_start.durationTo(t_end).toNanoseconds()));
fold(T, &gsink, sink);
}
const median_ns_per_op = computeStats(&samples, ITERS);
try writer.print(" {d:>7.1} │", .{median_ns_per_op});
}
try writer.print("\n", .{});
}
if (o_idx < Ops.len - 1) {
try writer.print("├─────────────┼──────┼─────────┼─────────┼─────────┤\n", .{});
}
}
try writer.print("└─────────────┴──────┴─────────┴─────────┴─────────┘\n", .{});
try writer.print("\nAnti-optimisation sink: {d:.4}\n", .{gsink});
try std.testing.expect(gsink != 0);
}