a

1 files changed, 51 insertions, 0 deletions

diff --git a/tests/bench/sieve.zc b/tests/bench/sieve.zc
new file mode 100644
index 0000000..1fb579b
--- /dev/null
+++ b/tests/bench/sieve.zc
@@ -0,0 +1,51 @@
+// primes below N. the same loops as tests/bench/sieve.c: one word per flag,
+// marks start at i*i. the count is 9592.
+//   a  fixed []int, bounds-checked, plain bytecode
+//   b  the same function lifted by o3
+//   c  o3 through a raw *int, no per-index check
+const int N = 100000;
+
+int sieve(fixed []int f) {
+	int n = len(f), c = 0;
+	for (int i = 2; i < n; i++) f[i] = 1;
+	for (int i = 2; i * i < n; i++)
+		if (f[i]) for (int j = i * i; j < n; j += i) f[j] = 0;
+	for (int i = 2; i < n; i++) c += f[i];
+	return c;
+}
+o3 int sieve3(fixed []int f) {
+	int n = len(f), c = 0;
+	for (int i = 2; i < n; i++) f[i] = 1;
+	for (int i = 2; i * i < n; i++)
+		if (f[i]) for (int j = i * i; j < n; j += i) f[j] = 0;
+	for (int i = 2; i < n; i++) c += f[i];
+	return c;
+}
+o3 int sieve_raw(int* f) {
+	int n = N, c = 0;
+	for (int i = 2; i < n; i++) f[i] = 1;
+	for (int i = 2; i * i < n; i++)
+		if (f[i]) for (int j = i * i; j < n; j += i) f[j] = 0;
+	for (int i = 2; i < n; i++) c += f[i];
+	return c;
+}
+int main() {
+	int which = get_c(), reps = 0, ch = get_c(), r = 0;
+	while (ch >= '0' && ch <= '9') { reps = reps * 10 + ch - '0'; ch = get_c(); }
+	if (which == 'c') {
+		int* raw = new(int, N);
+		while (reps > 0) { r = sieve_raw(raw); reps--; }
+		put_n(r); put_c(10);
+		free(d*raw);
+		return 0;
+	}
+	fixed []int f = new(fixed []int, N);
+	while (reps > 0) {
+		if (which == 'b') r = sieve3(f);
+		else r = sieve(f);
+		reps--;
+	}
+	put_n(r); put_c(10);
+	free(d*f);
+	return 0;
+}