X-Git-Url: https://git.saurik.com/apple/libdispatch.git/blobdiff_plain/d4e0f4aade4f18254fb326a5aa6c521fad1930d2..24954c793bca436d612851de3a460c72ef1f7b6d:/testing/float_parsing.c

diff --git a/testing/float_parsing.c b/testing/float_parsing.c
new file mode 100644
index 0000000..716bf50
--- /dev/null
+++ b/testing/float_parsing.c
@@ -0,0 +1,136 @@
+#include <dispatch/dispatch.h>
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <assert.h>
+#include <string.h>
+#include <math.h>
+
+#define MAXLAPS (512 * 1024)
+
+static void
+test(size_t LAPS, char *nums)
+{
+	uint64_t concurrent_cycles;
+	uint64_t serial_cycles;
+	char **result_strings;
+	char *nums_off;
+	double *results;
+	size_t i;
+
+	result_strings = calloc(1, sizeof(char *) * LAPS);
+	assert(result_strings);
+
+	results = calloc(1, sizeof(double) * LAPS);
+	assert(results);
+
+	printf("%zu random floats\n", LAPS);
+
+	i = 0;
+	nums_off = nums;
+	do {
+		result_strings[i] = nums_off;
+		do {
+			nums_off++;
+			assert(*nums_off);
+		} while (*nums_off != '\n');
+		i++;
+		nums_off++;
+	} while (i < LAPS);
+
+	for (i = 0; i < LAPS; i++) {
+		assert(result_strings[i]);
+	}
+
+	concurrent_cycles = dispatch_benchmark(10, ^{
+		dispatch_apply(LAPS, dispatch_get_concurrent_queue(0), ^(size_t idx) {
+			results[idx] = strtod(result_strings[idx], NULL);
+		});
+	});
+
+	for (i = 0; i < LAPS; i++) {
+		assert(results[i]);
+	}
+
+	serial_cycles = dispatch_benchmark(10, ^{
+		size_t k = 0;
+		do {
+			results[k] = strtod(result_strings[k], NULL);
+			k++;
+		} while (k < LAPS);
+	});
+
+	for (i = 0; i < LAPS; i++) {
+		assert(results[i]);
+	}
+
+	printf(	"\tserial cycles:\t%llu\n"
+			"\tapply() cycles:\t%llu\n"
+			"\tserial / concurrent: %.2Lf\n",
+		serial_cycles, concurrent_cycles,
+		(long double)serial_cycles / (long double)concurrent_cycles);
+
+	free(result_strings);
+	free(results);
+}
+
+int
+main(void)
+{
+	char path[PATH_MAX] = "/tmp/random_floats_XXXXXX";
+	struct stat sb;
+	double words[1000];
+	char buf[1024];
+	char *nums;
+	int fd, rfd;
+	size_t i, j;
+	ssize_t r;
+
+	rfd = open("/dev/random", O_RDONLY);
+	assert(rfd != -1);
+
+	fd = mkstemp(path);
+	assert(fd != -1);
+
+	r = unlink(path);
+	assert(r != -1);
+
+	i = 0;
+	do {
+		r = read(rfd, words, sizeof(words));
+		assert(r == sizeof(words));
+		for (j = 0; j < 1000; j++) {
+			if (isnormal(words[j])) {
+				r = write(fd, buf, snprintf(buf, sizeof(buf), "%.20e\n", words[j]));
+				assert(r != -1);
+				i++;
+			}
+		}
+	} while (i < MAXLAPS);
+
+	r = close(rfd);
+	assert(r != -1);
+
+	r = fstat(fd, &sb);
+	assert(r != -1);
+
+	nums = mmap(NULL, sb.st_size, PROT_READ, MAP_FILE|MAP_SHARED, fd, 0);
+	assert(nums != MAP_FAILED);
+
+	for (i = MAXLAPS; i > 0; i /= 2) {
+		test(i, nums);
+	}
+
+	r = munmap(nums, sb.st_size);
+	assert(r != -1);
+
+	r = close(fd);
+	assert(r != -1);
+
+	return 0;
+}