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package benchmark_runtime
import "base:runtime"
import "core:fmt"
import "core:log"
import "core:testing"
import "core:strings"
import "core:text/table"
import "core:time"
RUNS_PER_SIZE :: 2500
sizes := [?]int {
7, 8, 9,
15, 16, 17,
31, 32, 33,
63, 64, 65,
95, 96, 97,
128,
256,
512,
1024,
4096,
1024 * 1024,
}
// These are the normal, unoptimized algorithms.
plain_memory_equal :: proc "contextless" (x, y: rawptr, n: int) -> bool {
switch {
case n == 0: return true
case x == y: return true
}
a, b := ([^]byte)(x), ([^]byte)(y)
length := uint(n)
for i := uint(0); i < length; i += 1 {
if a[i] != b[i] {
return false
}
}
return true
}
plain_memory_compare :: proc "contextless" (a, b: rawptr, n: int) -> int #no_bounds_check {
switch {
case a == b: return 0
case a == nil: return -1
case b == nil: return +1
}
x := uintptr(a)
y := uintptr(b)
n := uintptr(n)
SU :: size_of(uintptr)
fast := n/SU + 1
offset := (fast-1)*SU
curr_block := uintptr(0)
if n < SU {
fast = 0
}
for /**/; curr_block < fast; curr_block += 1 {
va := (^uintptr)(x + curr_block * size_of(uintptr))^
vb := (^uintptr)(y + curr_block * size_of(uintptr))^
if va ~ vb != 0 {
for pos := curr_block*SU; pos < n; pos += 1 {
a := (^byte)(x+pos)^
b := (^byte)(y+pos)^
if a ~ b != 0 {
return -1 if (int(a) - int(b)) < 0 else +1
}
}
}
}
for /**/; offset < n; offset += 1 {
a := (^byte)(x+offset)^
b := (^byte)(y+offset)^
if a ~ b != 0 {
return -1 if (int(a) - int(b)) < 0 else +1
}
}
return 0
}
plain_memory_compare_zero :: proc "contextless" (a: rawptr, n: int) -> int #no_bounds_check {
x := uintptr(a)
n := uintptr(n)
SU :: size_of(uintptr)
fast := n/SU + 1
offset := (fast-1)*SU
curr_block := uintptr(0)
if n < SU {
fast = 0
}
for /**/; curr_block < fast; curr_block += 1 {
va := (^uintptr)(x + curr_block * size_of(uintptr))^
if va ~ 0 != 0 {
for pos := curr_block*SU; pos < n; pos += 1 {
a := (^byte)(x+pos)^
if a ~ 0 != 0 {
return -1 if int(a) < 0 else +1
}
}
}
}
for /**/; offset < n; offset += 1 {
a := (^byte)(x+offset)^
if a ~ 0 != 0 {
return -1 if int(a) < 0 else +1
}
}
return 0
}
run_trial_size_cmp :: proc(p: proc "contextless" (rawptr, rawptr, int) -> $R, size: int, idx: int, runs: int, loc := #caller_location) -> (timing: time.Duration) {
left := make([]u8, size)
right := make([]u8, size)
defer {
delete(left)
delete(right)
}
right[idx] = 0x01
accumulator: int
watch: time.Stopwatch
time.stopwatch_start(&watch)
for _ in 0..<runs {
result := p(&left[0], &right[0], size)
when R == bool {
assert(result == false, loc = loc)
accumulator += 1
} else when R == int {
assert(result == -1, loc = loc)
accumulator += result
}
}
time.stopwatch_stop(&watch)
timing = time.stopwatch_duration(watch)
log.debug(accumulator)
return
}
run_trial_size_zero :: proc(p: proc "contextless" (rawptr, int) -> int, size: int, idx: int, runs: int, loc := #caller_location) -> (timing: time.Duration) {
data := make([]u8, size)
defer delete(data)
data[idx] = 0x01
accumulator: int
watch: time.Stopwatch
time.stopwatch_start(&watch)
for _ in 0..<runs {
result := p(&data[0], size)
assert(result == 1, loc = loc)
accumulator += result
}
time.stopwatch_stop(&watch)
timing = time.stopwatch_duration(watch)
log.debug(accumulator)
return
}
run_trial_size :: proc {
run_trial_size_cmp,
run_trial_size_zero,
}
bench_table :: proc(algo_name: string, plain, simd: $P) {
string_buffer := strings.builder_make()
defer strings.builder_destroy(&string_buffer)
tbl: table.Table
table.init(&tbl)
defer table.destroy(&tbl)
table.aligned_header_of_values(&tbl, .Right, "Algorithm", "Size", "Iterations", "Scalar", "SIMD", "SIMD Relative (%)", "SIMD Relative (x)")
for size in sizes {
// Place the non-zero byte somewhere in the middle.
needle_index := size / 2
plain_timing := run_trial_size(plain, size, needle_index, RUNS_PER_SIZE)
simd_timing := run_trial_size(simd, size, needle_index, RUNS_PER_SIZE)
_plain := fmt.tprintf("%8M", plain_timing)
_simd := fmt.tprintf("%8M", simd_timing)
_relp := fmt.tprintf("%.3f %%", f64(simd_timing) / f64(plain_timing) * 100.0)
_relx := fmt.tprintf("%.3f x", 1 / (f64(simd_timing) / f64(plain_timing)))
table.aligned_row_of_values(
&tbl,
.Right,
algo_name,
size, RUNS_PER_SIZE, _plain, _simd, _relp, _relx)
}
builder_writer := strings.to_writer(&string_buffer)
fmt.sbprintln(&string_buffer)
table.write_plain_table(builder_writer, &tbl)
my_table_string := strings.to_string(string_buffer)
log.info(my_table_string)
}
@test
benchmark_memory_procs :: proc(t: ^testing.T) {
bench_table("memory_equal", plain_memory_equal, runtime.memory_equal)
bench_table("memory_compare", plain_memory_compare, runtime.memory_compare)
bench_table("memory_compare_zero", plain_memory_compare_zero, runtime.memory_compare_zero)
}
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