sync: use mfence on windows-tcc (#6079)

vlib/sync/bench/channel_bench_go.go

@@ -0,0 +1,68 @@
+package main
+
+import "fmt"
+import "log"
+import "os"
+import "time"
+import "strconv"
+
+func assert_eq(a, b int64) {
+	if a != b {
+		log.Fatalf("assertion failed\nleft: %d, right: %d\n", a, b)
+	}
+}
+
+func do_rec(ch chan int32, resch chan int64, n int32) {
+	var sum int64
+	var i int32
+	for i = 0; i < n; i++ {
+		sum += int64(<- ch)
+	}
+	fmt.Println(sum)
+	resch <- sum
+}
+
+func do_send(ch chan int32, start, end int32) {
+	for i := start; i < end; i++ {
+		ch <- i
+	}
+}
+
+func main() {
+	if len(os.Args) != 5 {
+		log.Fatalf("usage:\n\t%s <nsend> <nrec> <buflen> <nobj>\n", os.Args[0])
+	}
+	nsend, _ := strconv.Atoi(os.Args[1])
+	nrec, _ := strconv.Atoi(os.Args[2])
+	buflen, _ := strconv.Atoi(os.Args[3])
+	nobj, _ := strconv.Atoi(os.Args[4])
+	stopwatch := time.Now()
+	ch := make(chan int32, buflen)
+	resch := make(chan int64, 0)
+	no := nobj
+	for i := 0; i < nrec; i++ {
+		n := no / (nrec - i)
+		go do_rec(ch, resch, int32(n))
+		no -= n
+	}
+	assert_eq(int64(no), 0)	
+	no = nobj
+	for i := 0; i < nsend; i++ {
+		n := no / (nsend - i)
+		end := no
+		no -= n
+		go do_send(ch, int32(no), int32(end))
+	}
+	assert_eq(int64(no), 0)	
+	var sum int64
+	for i := 0; i < nrec; i++ {
+		sum += <-resch
+	}
+	elapsed := time.Now().Sub(stopwatch)
+	rate := float64(nobj)/float64(elapsed.Nanoseconds())*1000.0
+	duration := 1.0e-09 * float64(elapsed.Nanoseconds())
+	fmt.Printf("%d objects in %g s (%.2f objs/µs)\n", nobj, duration, rate)
+	expected_sum := int64(nobj)*int64(nobj-1)/2
+	fmt.Printf("got: %d, expected: %d\n", sum, expected_sum)
+	assert_eq(sum, expected_sum)
+}