tests/benchmark: Add RNG benchmarks

Author: Yawning

tests/benchmark/all.odin

@@ -3,5 +3,6 @@ package benchmarks
 @(require) import "bytes"
 @(require) import "crypto"
 @(require) import "hash"
+@(require) import "math"
 @(require) import "text/regex"
 @(require) import "strings"

tests/benchmark/math/benchmark_rand.odin

@@ -0,0 +1,130 @@
+package benchmark_core_math
+
+import "base:runtime"
+
+import "core:fmt"
+import "core:math/rand"
+import "core:log"
+import "core:strings"
+import "core:testing"
+import "core:text/table"
+import "core:time"
+
+@(private = "file")
+ITERS :: 10000000
+@(private = "file")
+ITERS_BULK :: 1000
+
+@(private = "file")
+SAMPLE_SEED : string : "ABCDEFGHIJKLMNOPQRSTUVWXYZ123456"
+
+@(test)
+benchmark_rng :: proc(t: ^testing.T) {
+	runtime.DEFAULT_TEMP_ALLOCATOR_TEMP_GUARD()
+
+	tbl: table.Table
+	table.init(&tbl)
+	defer table.destroy(&tbl)
+
+	table.caption(&tbl, "RNG")
+	table.aligned_header_of_values(&tbl, .Right, "Algorithm", "Size", "Time", "Throughput")
+
+	context.random_generator = rand.default_random_generator()
+	rand.reset_bytes(transmute([]byte)(SAMPLE_SEED))
+	_benchmark_u64(t, &tbl, "chacha8rand")
+	_benchmark_large(t, &tbl, "chacha8rand")
+
+	table.row(&tbl)
+
+	context.random_generator = rand.pcg_random_generator()
+	_benchmark_u64(t, &tbl, "pcg64")
+	_benchmark_large(t, &tbl, "pcg64")
+	
+	table.row(&tbl)
+
+	context.random_generator = rand.xoshiro256_random_generator()
+	_benchmark_u64(t, &tbl, "xorshiro256**")
+	_benchmark_large(t, &tbl, "xorshiro256**")
+
+	log_table(&tbl)
+}
+
+@(private = "file")
+_benchmark_u64 :: proc(t: ^testing.T, tbl: ^table.Table, algo_name: string) {
+	options := &time.Benchmark_Options{
+		rounds = ITERS,
+		bytes = 8,
+		setup = nil,
+		bench = proc(options: ^time.Benchmark_Options, allocator: runtime.Allocator) -> (err: time.Benchmark_Error){
+			sum: u64
+			for _ in 0 ..= options.rounds {
+				sum += rand.uint64()
+			}
+			options.hash = u128(sum)
+			options.count = options.rounds
+			options.processed = options.rounds * options.bytes
+			return
+		},
+		teardown = nil,
+	}
+
+	err := time.benchmark(options, context.allocator)
+	testing.expect(t, err == nil)
+
+	time_per_iter := options.duration / ITERS
+	table.aligned_row_of_values(
+		tbl,
+		.Right,
+		algo_name,
+		table.format(tbl, "uint64"),
+		table.format(tbl, "%8M", time_per_iter),
+		table.format(tbl, "%5.3f MiB/s", options.megabytes_per_second),
+	)
+}
+
+@(private = "file")
+_benchmark_large :: proc(t: ^testing.T, tbl: ^table.Table, algo_name: string) {
+	options := &time.Benchmark_Options{
+		rounds = ITERS_BULK,
+		bytes = 1024768,
+		setup = nil,
+		bench = proc(options: ^time.Benchmark_Options, allocator: runtime.Allocator) -> (err: time.Benchmark_Error){
+			n: int
+			for _ in 0 ..= options.rounds {
+				n += rand.read(options.output)
+			}
+			options.hash = u128(n)
+			options.count = options.rounds
+			options.processed = options.rounds * options.bytes
+			return
+		},
+		output = make([]byte, 1024768, context.temp_allocator),
+		teardown = nil,
+	}
+
+	err := time.benchmark(options, context.allocator)
+	testing.expect(t, err == nil)
+
+	time_per_iter := options.duration / ITERS_BULK
+	table.aligned_row_of_values(
+		tbl,
+		.Right,
+		algo_name,
+		table.format(tbl, "1 MiB"),
+		table.format(tbl, "%8M", time_per_iter),
+		table.format(tbl, "%5.3f MiB/s", options.megabytes_per_second),
+	)
+}
+
+@(private)
+log_table :: proc(tbl: ^table.Table) {
+	sb := strings.builder_make()
+	defer strings.builder_destroy(&sb)
+
+	wr := strings.to_writer(&sb)
+
+	fmt.sbprintln(&sb)
+	table.write_plain_table(wr, tbl)
+
+	log.info(strings.to_string(sb))
+}