From: Michal Nazarewicz on
This commit adds a test application for the put_dec() and
family of functions that are used by the previous two commits.

Signed-off-by: Michal Nazarewicz <mina86(a)mina86.com>
---
tools/put-dec/Makefile | 14 +
tools/put-dec/put-dec-test.c | 942 ++++++++++++++++++++++++++++++++++++++++++
2 files changed, 956 insertions(+), 0 deletions(-)
create mode 100644 tools/put-dec/Makefile
create mode 100644 tools/put-dec/put-dec-test.c

diff --git a/tools/put-dec/Makefile b/tools/put-dec/Makefile
new file mode 100644
index 0000000..77400c9
--- /dev/null
+++ b/tools/put-dec/Makefile
@@ -0,0 +1,14 @@
+put-dec-test: put-dec-test.c
+ exec $(CC) -Wall -Wextra -O2 -o $@ $<
+
+put-dec-test.s: put-dec-test.c
+ exec $(CC) -Wall -Wextra -O2 -S -o $@ $<
+
+put-dec-test-s: put-dec-test.c
+ exec $(CC) -Wall -Wextra -Os -o $@ $<
+
+put-dec-test-s.s: put-dec-test.c
+ exec $(CC) -Wall -Wextra -Os -S -o $@ $<
+
+clean:
+ rm -f -- put-dec-test
diff --git a/tools/put-dec/put-dec-test.c b/tools/put-dec/put-dec-test.c
new file mode 100644
index 0000000..1860ae3
--- /dev/null
+++ b/tools/put-dec/put-dec-test.c
@@ -0,0 +1,942 @@
+/*
+ * put-dec-test.c -- Variaus put_dec*() functions implementation
+ * testing and benchmarking tool
+ * Written by Michal Nazarewicz <mina86(a)mina86.com>
+ * with helpful suggestions by Denys Vlasenko <vda.linux(a)googlemail.com>
+ */
+#define _BSD_SOURCE
+
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+
+#if CHAR_BIT != 8
+# error This code assumes CHAR_BIT == 8
+#endif
+
+
+
+# define do_div(n, base) ({ \
+ uint32_t __base = (base); \
+ uint32_t __rem = (n) % __base; \
+ (n) /= __base; \
+ __rem; \
+ })
+
+
+/****************************** Original versian ******************************/
+
+static char *orig_put_dec_trunc(char *buf, unsigned q)
+{
+ unsigned d3, d2, d1, d0;
+ d1 = (q>>4) & 0xf;
+ d2 = (q>>8) & 0xf;
+ d3 = (q>>12);
+
+ d0 = 6*(d3 + d2 + d1) + (q & 0xf);
+ q = (d0 * 0xcd) >> 11;
+ d0 = d0 - 10*q;
+ *buf++ = d0 + '0'; /* least significant digit */
+ d1 = q + 9*d3 + 5*d2 + d1;
+ if (d1 != 0) {
+ q = (d1 * 0xcd) >> 11;
+ d1 = d1 - 10*q;
+ *buf++ = d1 + '0'; /* next digit */
+
+ d2 = q + 2*d2;
+ if ((d2 != 0) || (d3 != 0)) {
+ q = (d2 * 0xd) >> 7;
+ d2 = d2 - 10*q;
+ *buf++ = d2 + '0'; /* next digit */
+
+ d3 = q + 4*d3;
+ if (d3 != 0) {
+ q = (d3 * 0xcd) >> 11;
+ d3 = d3 - 10*q;
+ *buf++ = d3 + '0'; /* next digit */
+ if (q != 0)
+ *buf++ = q + '0'; /* most sign. digit */
+ }
+ }
+ }
+
+ return buf;
+}
+/* Same with if's removed. Always emits five digits */
+static char *orig_put_dec_full(char *buf, unsigned q)
+{
+ /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
+ /* but anyway, gcc produces better code with full-sized ints */
+ unsigned d3, d2, d1, d0;
+ d1 = (q>>4) & 0xf;
+ d2 = (q>>8) & 0xf;
+ d3 = (q>>12);
+
+ /*
+ * Possible ways to approx. divide by 10
+ * gcc -O2 replaces multiply with shifts and adds
+ * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
+ * (x * 0x67) >> 10: 1100111
+ * (x * 0x34) >> 9: 110100 - same
+ * (x * 0x1a) >> 8: 11010 - same
+ * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
+ */
+ d0 = 6*(d3 + d2 + d1) + (q & 0xf);
+ q = (d0 * 0xcd) >> 11;
+ d0 = d0 - 10*q;
+ *buf++ = d0 + '0';
+ d1 = q + 9*d3 + 5*d2 + d1;
+ q = (d1 * 0xcd) >> 11;
+ d1 = d1 - 10*q;
+ *buf++ = d1 + '0';
+
+ d2 = q + 2*d2;
+ q = (d2 * 0xd) >> 7;
+ d2 = d2 - 10*q;
+ *buf++ = d2 + '0';
+
+ d3 = q + 4*d3;
+ q = (d3 * 0xcd) >> 11; /* - shorter code */
+ /* q = (d3 * 0x67) >> 10; - would also work */
+ d3 = d3 - 10*q;
+ *buf++ = d3 + '0';
+ *buf++ = q + '0';
+
+ return buf;
+}
+
+static __attribute__((noinline))
+char *orig_put_dec(char *buf, unsigned long long num)
+{
+ while (1) {
+ unsigned rem;
+ if (num < 100000)
+ return orig_put_dec_trunc(buf, num);
+ rem = do_div(num, 100000);
+ buf = orig_put_dec_full(buf, rem);
+ }
+}
+
+
+
+/****************************** Modified versions ******************************/
+
+/*
+ * Decimal conversion is by far the most typical, and is used for
+ * /proc and /sys data. This directly impacts e.g. top performance
+ * with many processes running.
+ *
+ * We optimize it for speed using code based on idea described at:
+ * http://www.cs.uiowa.edu/~jones/bcd/decimal.html (with permission
+ * from the author, Douglas W. Jones).
+ *
+ * The original code was designed for 8-bit ALus but since we can
+ * assume more capable hardware the code has been rewritten to use the
+ * following properties:
+ *
+ * n = 1 * n0 + ( 0 <= n0 <= 1023 )
+ * 1024 * n1 ( 0 <= n1 <= 97 )
+ * a0 = 0 + 4 * n1 + 1 * n0 ( 0 <= a0 <= 1412 )
+ * a1 = (a0 / 10) + 2 * n1 ( 0 <= a1 <= 335 )
+ * a2 = (a1 / 10) + 0 * n1 ( 0 <= a2 <= 33 )
+ * a3 = (a2 / 10) + 1 * n1 ( 0 <= a3 <= 100 )
+ * d0 = a0 % 10
+ * d1 = a1 % 10
+ * d2 = a2 % 10
+ * d3 = a3 % 10
+ * d4 = a3 / 10
+ *
+ * So instead of dividing the number into four nibles we divide it
+ * into two numbers: first one 10-bit and the other one 7-bit
+ * (argument is 17-bit number from 0 to 99999).
+ *
+ * Moreover, 1024, which is the value second part of the number needs
+ * to be multiplied by, has nice property that each digit is a power
+ * of two or zero -- this helps with multiplications.
+ *
+ * Possible ways to approx. divide by 10
+ * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
+ * (x * 0x67) >> 10: 1100111
+ * (x * 0x34) >> 9: 110100 - same
+ * (x * 0x1a) >> 8: 11010 - same
+ * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
+ */
+static char *mod1_put_dec_full(char *buf, unsigned q)
+{
+ unsigned p, r;
+ p = q >> 10;
+
+ q &= 0x3ff;
+ q += 4 * p;
+ r = (q * 0x199A) >> 16;
+ *buf++ = (q - 10 * r) + '0';
+
+ r += 2 * p;
+ q = (r * 0xcd) >> 11;
+ *buf++ = (r - 10 * q) + '0';
+
+ /* q += 0; */
+ r = (q * 0xcd) >> 11;
+ *buf++ = (q - 10 * r) + '0';
+
+ r += p;
+ q = (r * 0xcd) >> 11;
+ *buf++ = (r - 10 * q) + '0';
+
+ *buf++ = q + '0';
+
+ return buf;
+}
+
+static char *mod1_put_dec_trunc(char *buf, unsigned q)
+{
+ unsigned p, r;
+ p = q >> 10;
+
+ q &= 0x3ff;
+ q += 4 * p;
+ r = (q * 0x199a) >> 16;
+ *buf++ = (q - 10 * r) + '0';
+
+ r += 2 * p;
+ if (r) {
+ q = (r * 0xcd) >> 11;
+ *buf++ = (r - 10 * q) + '0';
+
+ /* q += 0; */
+ if (q || p) {
+ r = (q * 0xcd) >> 11;
+ *buf++ = (q - 10 * r) + '0';
+
+ r += p;
+ if (r) {
+ q = (r * 0xcd) >> 11;
+ *buf++ = (r - 10 * q) + '0';
+
+ if (q)
+ *buf++ = q + '0';
+ }
+ }
+ }
+
+ return buf;
+}
+
+
+static __attribute__((noinline))
+char *mod1_put_dec(char *buf, unsigned long long num)
+{
+ while (1) {
+ unsigned rem;
+ if (num < 100000)
+ return mod1_put_dec_trunc(buf, num);
+ rem = do_div(num, 100000);
+ buf = mod1_put_dec_full(buf, rem);
+ }
+}
+
+
+static __attribute__((noinline))
+char *mod2_put_dec(char *buf, unsigned long long num)
+{
+ if (!num) {
+ *buf++ = '0';
+ return buf;
+ }
+
+ while (num >= 100000) {
+ unsigned rem;
+ rem = do_div(num, 100000);
+ buf = mod1_put_dec_full(buf, rem);
+ }
+
+ buf = mod1_put_dec_full(buf, num);
+ while (buf[-1] == '0')
+ --buf;
+ return buf;
+}
+
+
+
+/*
+ * Decimal conversion is by far the most typical, and is used for
+ * /proc and /sys data. This directly impacts e.g. top performance
+ * with many processes running.
+ *
+ * We optimize it for speed using ideas described at
+ * <http://www.cs.uiowa.edu/~jones/bcd/divide.html>.
+ *
+ * '(num * 0xcccd) >> 19' is an approximation of 'num / 10' that gives
+ * correct results for num < 81920. Because of this, we check at the
+ * beginning if we are dealing with a number that may cause trouble
+ * and if so, we make it smaller.
+ *
+ * (As a minor note, all operands are always 16 bit so this function
+ * should work well on hardware that cannot multiply 32 bit numbers).
+ *
+ * (Previous a code based on
+ * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html> was used here,
+ * with permission from the author, Douglas W. Jones.)
+ *
+ * Other, possible ways to approx. divide by 10
+ * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
+ * (x * 0x67) >> 10: 1100111
+ * (x * 0x34) >> 9: 110100 - same
+ * (x * 0x1a) >> 8: 11010 - same
+ * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
+ */
+static char *mod3_put_dec_full(char *buf, unsigned q)
+{
+ unsigned r;
+ char a = '0';
+
+ if (q >= 50000) {
+ a = '5';
+ q -= 50000;
+ }
+
+ r = (q * 0xcccd) >> 19;
+ *buf++ = (q - 10 * r) + '0';
+
+ q = (r * 0x199a) >> 16;
+ *buf++ = (r - 10 * q) + '0';
+
+ r = (q * 0xcd) >> 11;
+ *buf++ = (q - 10 * r) + '0';
+
+ q = (r * 0xd) >> 7;
+ *buf++ = (r - 10 * q) + '0';
+
+ *buf++ = q + a;
+
+ return buf;
+}
+
+static char *mod3_put_dec_trunc(char *buf, unsigned q)
+{
+ unsigned r;
+
+ /*
+ * We need to check if num is < 81920 so we might as well
+ * check if we can just call the _full version of this
+ * function.
+ */
+ if (q > 9999)
+ return mod3_put_dec_full(buf, q);
+
+ r = (q * 0xcccd) >> 19;
+ *buf++ = (q - 10 * r) + '0';
+
+ if (r) {
+ q = (r * 0x199a) >> 16;
+ *buf++ = (r - 10 * q) + '0';
+
+ if (q) {
+ r = (q * 0xcd) >> 11;
+ *buf++ = (q - 10 * r) + '0';
+
+ if (r)
+ *buf++ = r + '0';
+ }
+ }
+
+ return buf;
+}
+
+
+static char *mod3_put_dec_8bit(char *buf, unsigned q)
+{
+ unsigned r;
+
+ r = (q * 0xcd) >> 11;
+ *buf++ = (q - 10 * r) + '0';
+
+ if (r) {
+ q = (r * 0xd) >> 7;
+ *buf++ = (r - 10 * q) + '0';
+
+ if (q)
+ *buf++ = q + '0';
+ }
+
+ return buf;
+}
+
+
+static __attribute__((noinline))
+char *mod3_put_dec(char *buf, unsigned long long num)
+{
+ while (1) {
+ unsigned rem;
+ if (num < 100000)
+ return mod3_put_dec_trunc(buf, num);
+ rem = do_div(num, 100000);
+ buf = mod3_put_dec_full(buf, rem);
+ }
+}
+
+
+static __attribute__((noinline))
+char *mod4_put_dec(char *buf, unsigned long long num)
+{
+ if (!num) {
+ *buf++ = '0';
+ return buf;
+ }
+
+ while (num >= 100000) {
+ unsigned rem;
+ rem = do_div(num, 100000);
+ buf = mod3_put_dec_full(buf, rem);
+ }
+
+ buf = mod3_put_dec_full(buf, num);
+ while (buf[-1] == '0')
+ --buf;
+ return buf;
+}
+
+
+
+/*
+ * Decimal conversion is by far the most typical, and is used for
+ * /proc and /sys data. This directly impacts e.g. top performance
+ * with many processes running.
+ *
+ * We optimize it for speed using ideas described at
+ * <http://www.cs.uiowa.edu/~jones/bcd/divide.html>.
+ *
+ * (Previous a code based on
+ * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html> was used here,
+ * with permission from the author, Douglas W. Jones.)
+ *
+ * Other, possible ways to approx. divide by 10
+ * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
+ * (x * 0x67) >> 10: 1100111
+ * (x * 0x34) >> 9: 110100 - same
+ * (x * 0x1a) >> 8: 11010 - same
+ * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
+ */
+static char *mod5_put_dec_full(char *buf, unsigned q)
+{
+ unsigned r;
+
+ r = (q * 0xcccd) >> 19;
+ *buf++ = (q - 10 * r) + '0';
+
+ q = (r * 0x199a) >> 16;
+ *buf++ = (r - 10 * q) + '0';
+
+ r = (q * 0xcd) >> 11;
+ *buf++ = (q - 10 * r) + '0';
+
+ *buf++ = r + '0';
+
+ return buf;
+}
+
+static char *mod5_put_dec_trunc(char *buf, unsigned q)
+{
+ unsigned r;
+
+ r = (q * 0xcccd) >> 19;
+ *buf++ = (q - 10 * r) + '0';
+
+ if (r) {
+ q = (r * 0x199a) >> 16;
+ *buf++ = (r - 10 * q) + '0';
+
+ if (q) {
+ r = (q * 0xcd) >> 11;
+ *buf++ = (q - 10 * r) + '0';
+
+ if (r)
+ *buf++ = r + '0';
+ }
+ }
+
+ return buf;
+}
+
+
+static __attribute__((noinline))
+char *mod5_put_dec(char *buf, unsigned long long num)
+{
+ while (1) {
+ unsigned rem;
+ if (num < 10000)
+ return mod5_put_dec_trunc(buf, num);
+ rem = do_div(num, 10000);
+ buf = mod5_put_dec_full(buf, rem);
+ }
+}
+
+/*
+ * Based on code by Douglas W. Jones found at
+ * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html>.
+ */
+static __attribute__((noinline))
+char *mod6_put_dec(char *buf, unsigned long long n)
+{
+ uint32_t d3, d2, d1, q;
+
+ if (!n) {
+ *buf++ = '0';
+ return buf;
+ }
+
+ d1 = (n >> 16) & 0xFFFF;
+ d2 = (n >> 32) & 0xFFFF;
+ d3 = (n >> 48) & 0xFFFF;
+
+ q = 656 * d3 + 7296 * d2 + 5536 * d1 + (n & 0xFFFF);
+
+ buf = mod5_put_dec_full(buf, q % 10000);
+ q = q / 10000;
+
+ d1 = q + 7671 * d3 + 9496 * d2 + 6 * d1;
+ buf = mod5_put_dec_full(buf, d1 % 10000);
+ q = d1 / 10000;
+
+ d2 = q + 4749 * d3 + 42 * d2;
+ buf = mod5_put_dec_full(buf, d2 % 10000);
+ q = d2 / 10000;
+
+ d3 = q + 281 * d3;
+ buf = mod5_put_dec_full(buf, d3 % 10000);
+ q = d3 / 10000;
+
+ buf = mod5_put_dec_trunc(buf, q);
+
+ while (buf[-1] == '0')
+ --buf;
+
+ return buf;
+}
+
+
+/*
+ * Based on code by Douglas W. Jones found at
+ * <http://www.cs.uiowa.edu/~jones/bcd/decimal.html>.
+ */
+static __attribute__((noinline))
+char *mod7_put_dec(char *buf, unsigned long long n)
+{
+ uint32_t d3, d2, d1, q;
+
+ if (!n) {
+ *buf++ = '0';
+ return buf;
+ }
+
+ d1 = (n >> 16) & 0xFFFF;
+ d2 = (n >> 32) & 0xFFFF;
+ d3 = (n >> 48) & 0xFFFF;
+
+ q = 656 * d3 + 7296 * d2 + 5536 * d1 + (n & 0xFFFF);
+
+ buf = mod5_put_dec_full(buf, q % 10000);
+ q = q / 10000;
+
+ d1 = q + 7671 * d3 + 9496 * d2 + 6 * d1;
+ if (d1) {
+ buf = mod5_put_dec_full(buf, d1 % 10000);
+ q = d1 / 10000;
+
+ d2 = q + 4749 * d3 + 42 * d2;
+ if (d2) {
+ buf = mod5_put_dec_full(buf, d2 % 10000);
+ q = d2 / 10000;
+
+ d3 = q + 281 * d3;
+ if (d3) {
+ buf = mod5_put_dec_full(buf, d3 % 10000);
+ q = d3 / 10000;
+
+ if (q)
+ buf = mod5_put_dec_trunc(buf, q);
+ }
+ }
+ }
+
+ while (buf[-1] == '0')
+ --buf;
+
+ return buf;
+}
+
+
+static __attribute__((noinline))
+char *mod8_put_dec(char *buf, unsigned long long num)
+{
+ while (1) {
+ unsigned rem = do_div(num, 100000000);
+
+ if (!num && rem < 10000)
+ return mod5_put_dec_trunc(buf, rem);
+ buf = mod5_put_dec_full(buf, rem % 10000);
+
+ if (!num)
+ return mod5_put_dec_trunc(buf, rem / 10000);
+ buf = mod5_put_dec_full(buf, rem / 10000);
+ }
+}
+
+
+
+/****************************** Main ******************************/
+
+static const struct put_dec_helper {
+ const char *name;
+ char *(*func)(char *buf, unsigned v);
+ unsigned inner;
+ unsigned outer;
+ int width;
+} put_dec_helpers[] = {
+ { "orig_put_dec_full" , orig_put_dec_full , 100000, 1, 5 },
+ { "mod1_put_dec_full" , mod1_put_dec_full , 100000, 1, 5 },
+ { "mod3_put_dec_full" , mod3_put_dec_full , 100000, 1, 5 },
+ { "mod5_put_dec_full" , mod5_put_dec_full , 10000, 10, 4 },
+ { "orig_put_dec_trunc", orig_put_dec_trunc, 100000, 1, 0 },
+ { "mod1_put_dec_trunc", mod1_put_dec_trunc, 100000, 1, 0 },
+ { "mod3_put_dec_trunc", mod3_put_dec_trunc, 100000, 1, 0 },
+ { "mod5_put_dec_trunc", mod5_put_dec_trunc, 10000, 10, 0 },
+ { "mod3_put_dec_8bit", mod3_put_dec_8bit, 256, 500, 0 },
+ { NULL, NULL, 0, 0, 0 }
+};
+
+static const struct put_dec {
+ const char *name;
+ char *(*func)(char *buf, unsigned long long v);
+} put_decs[] = {
+ { "orig_put_dec" , orig_put_dec },
+ { "mod1_put_dec" , mod1_put_dec },
+ { "mod2_put_dec" , mod2_put_dec },
+ { "mod3_put_dec" , mod3_put_dec },
+ { "mod4_put_dec" , mod4_put_dec },
+ { "mod5_put_dec" , mod5_put_dec },
+ { "mod6_put_dec" , mod6_put_dec },
+ { "mod7_put_dec" , mod7_put_dec },
+ { "mod8_put_dec" , mod8_put_dec },
+ { NULL, NULL }
+};
+
+
+#define WIDTH (int)(sizeof(long long) * 4)
+static char buf_output[WIDTH], buf_expected[WIDTH];
+
+
+static bool load_random(const char *file);
+static void benchmark_helpers(unsigned long iterations);
+static void benchmark_put_dec(unsigned long iterations);
+static void show_sizes(char *app);
+static bool test_helpers(void);
+static bool test_put_dec_rand(void);
+static bool test_put_dec_range(unsigned long long range);
+
+
+int main(int argc, char **argv) {
+ unsigned long iterations;
+ unsigned long long range;
+ bool ret;
+
+ puts(">> Reading etropy...");
+ fflush(NULL);
+
+ if (!load_random("/dev/urandom"))
+ return 2;
+
+ iterations = 1000;
+ if (argc > 1)
+ iterations = atoi(argv[1]);
+
+ if (iterations) {
+ puts(">> Benchmarking...");
+ fflush(NULL);
+
+ benchmark_helpers(iterations);
+ benchmark_put_dec(iterations * 25000);
+ }
+
+ puts(">> Sizes");
+ show_sizes(*argv);
+
+ puts(">> Testing...");
+ fflush(NULL);
+
+ memset(buf_output, 77, sizeof buf_output);
+
+ range = 10*1000*1000;
+ if (argc > 2)
+ range = atoi(argv[2]);
+
+ ret = test_helpers();
+ ret = test_put_dec_rand() && ret;
+ if (range)
+ ret = test_put_dec_range(range) && ret;
+
+ printf(">> %s%*s\n",
+ ret
+ ? "Everything went fine"
+ : "Some test failed, consult stderr",
+ WIDTH, "");
+
+ return ret;
+}
+
+
+static bool test(const char *name, char *b, char *fmt, ...);
+static void stop(const char *name, struct timeval *start);
+
+static unsigned long long __random[1 << 20];
+static inline unsigned long long randll(unsigned n) {
+ return __random[n & ((sizeof __random / sizeof *__random) - 1)];
+}
+
+
+static bool load_random(const char *file)
+{
+ size_t left, pos;
+ bool ret = true;
+ int fd;
+
+ fd = open(file, O_RDONLY);
+ if (fd < 0) {
+ perror(file);
+ return false;
+ }
+
+ left = sizeof __random;
+ pos = 0;
+ do {
+ ssize_t r = read(fd, ((char *)__random) + pos, left);
+ if (r > 0) {
+ pos += r;
+ left -= r;
+ } else if (r == 0) {
+ printf("%s: file too small\n", file);
+ ret = false;
+ break;
+ } else if (errno == EAGAIN || errno == EINTR) {
+ /* nothing */
+ } else {
+ perror(file);
+ ret = false;
+ break;
+ }
+ } while (left);
+
+ close(fd);
+ return ret;
+}
+
+
+static void benchmark_helpers(unsigned long iterations)
+{
+ const struct put_dec_helper *helper = put_dec_helpers;
+
+ printf("\thelpers (%lu iterations)\n", iterations * 100000);
+ fflush(NULL);
+
+ do {
+ char *(*func)(char *buf, unsigned v);
+ struct timeval start;
+ unsigned long o;
+ unsigned inner;
+
+ func = helper->func;
+ o = helper->outer * iterations;
+ inner = helper->inner;
+ gettimeofday(&start, NULL);
+
+ do {
+ unsigned i = inner;
+ do {
+ func(buf_output, i);
+ } while (--i);
+ } while (--o);
+
+ stop(helper->name, &start);
+ ++helper;
+ } while (helper->name);
+
+ fflush(NULL);
+}
+
+static void benchmark_put_dec(unsigned long iterations)
+{
+ const struct put_dec *pd = put_decs;
+
+ printf("\tput_dec (%lu iterations)\n", iterations);
+ fflush(NULL);
+
+ do {
+ char *(*func)(char *buf, unsigned long long v);
+ struct timeval start;
+ unsigned long i;
+
+ func = pd->func;
+ i = iterations;
+ gettimeofday(&start, NULL);
+
+ do {
+ func(buf_output, randll(--i));
+ } while (i);
+
+ stop(pd->name, &start);
+ ++pd;
+ } while (pd->name);
+
+ fflush(NULL);
+}
+
+static void show_sizes(char *app)
+{
+ setenv("APP", app, 1);
+ printf("\tobjdump -t '%s' | grep -F _put_dec | cut -f 2-\n", app);
+ fflush(NULL);
+ system("objdump -t \"$APP\" | grep -F _put_dec | cut -f 2-");
+}
+
+static bool test_helpers(void)
+{
+ const struct put_dec_helper *helper = put_dec_helpers;
+ bool ret = true;
+
+ puts("\thelpers");
+ fflush(NULL);
+
+ do {
+ unsigned i = helper->inner;
+
+ do {
+ --i;
+
+ ret = test(helper->name, helper->func(buf_output, i),
+ "%0*u", helper->width, i) && ret;
+ } while (i);
+
+ ++helper;
+ } while (helper->name);
+
+ fflush(NULL);
+
+ return ret;
+}
+
+static bool __test_put_dec(unsigned long long v, bool print)
+{
+ const struct put_dec *pd = put_decs;
+ bool ret = true;
+
+ sprintf(buf_expected, "%llu", v);
+
+ if (print) {
+ printf("\ttesting: %*s\r", WIDTH, buf_expected);
+ fflush(NULL);
+ }
+
+ do {
+ ret = test(pd->name, pd->func(buf_output, v), NULL) && ret;
+ ++pd;
+ } while (pd->name);
+
+ return ret;
+}
+
+static bool test_put_dec_rand(void)
+{
+ size_t i = sizeof __random / sizeof *__random;
+ bool ret = true;
+
+ printf("\tput_dec, %zu random numbers\n", i);
+ fflush(NULL);
+
+ do {
+ --i;
+ ret = __test_put_dec(randll(i), !(i & 0xffff)) && ret;
+ } while (i);
+
+ return ret;
+}
+
+static bool test_put_dec_range(unsigned long long range)
+{
+ unsigned long long edge = 1;
+ bool ret = true;
+
+ printf("\tput_dec, %llu numbers around the \"edges\"%10s\n", range, "");
+ fflush(NULL);
+
+ do {
+ unsigned long long i = 2 * range, v = edge - range;
+ do {
+ ret = __test_put_dec(v, !(i & 0xffff)) && ret;
+ ++v;
+ } while (--i);
+
+ edge <<= 16;
+ } while (edge);
+
+ return ret;
+}
+
+
+static bool test(const char *name, char *b, char *fmt, ...)
+{
+ char *a = buf_output;
+ va_list ap;
+ bool ret;
+
+ *b-- = '\0';
+ while (a < b) {
+ char tmp = *a;
+ *a = *b;
+ *b = tmp;
+ ++a;
+ --b;
+ }
+
+ if (fmt) {
+ va_start(ap, fmt);
+ vsprintf(buf_expected, fmt, ap);
+ va_end(ap);
+ }
+
+ ret = !strcmp(buf_output, buf_expected);
+ if (!ret)
+ fprintf(stderr, "%-20s: expecting %*s got %*s\n",
+ name, WIDTH, buf_expected, WIDTH, buf_output);
+
+ memset(buf_output, 77, sizeof buf_output);
+
+ return ret;
+}
+
+static void stop(const char *name, struct timeval *start)
+{
+ struct timeval stop;
+ gettimeofday(&stop, NULL);
+
+ stop.tv_sec -= start->tv_sec;
+ if (stop.tv_usec < start->tv_usec) {
+ --stop.tv_sec;
+ stop.tv_usec += 1000000;
+ }
+ stop.tv_usec -= start->tv_usec;
+
+ fflush(NULL);
+ printf("%-20s: %3lu.%06lus\n", name,
+ (unsigned long)stop.tv_sec, (unsigned long)stop.tv_usec);
+}
--
1.7.1

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